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zimm17
07-15-2007, 08:36 AM
Did a few runs yesterday to further tune the ECU- but the O2 sensor quit reading right- I pulled it out and it had gotten wet. I guess that thing is toast. New sensor on order.

I did about 7 full power, 80mph runs of about 2 minutes each. Engine temp stayed at 190 (closed loop cooling), but oil pressure dropped to 15 running, and 5 at idle. Then it dropped to zero so I shut her down and put it back on the trailer. At home I put a mechanical gauge on it and it showed 8 psi at idle- 15 at 2000rpm- that's with the oil not hot.

My theory is that the oil is getting too hot. I have a oil temp gauge on order.

I also think I need to replumb the oil cooler so it gets water before the heat exchanger. It'll make the hose runs longer, but I think the oil cooler needs the coldest water.

gcarter
07-15-2007, 10:17 AM
I also think I need to replumb the oil cooler so it gets water before the heat exchanger. It'll make the hose runs longer, but I think the oil cooler needs the coldest water.
That's definately a step in the right direction, and maybe a larger one.

BUIZILLA
07-15-2007, 11:13 AM
me thinks you got's more problems than that... :boggled:

mrfixxall
07-15-2007, 11:48 AM
me with Buiz,you have more issues then you think!!! bearing clearances,,or oil pump be wacky..pull it

superchargers= detination = pounding rod bearings out of rods..or sh!t in oil pan with clogged screen

gold-n-rod
07-15-2007, 12:49 PM
Yikes, put me on the pessimist list. :(

Once back home and cooled down, you should have had at least 40# at 2000 rpms.

My Merc manual says minimum oil pressure should be 6 psi @ idle and 18 psi @ 2000 rpms...... but we're talking stock Merc engines. Boosted as yours is, you'll want better.

Warmed up, my 5.0 MPI runs 40# above idle and 20-25 at idle (the 20 after WOT runs). I run M1 20-50 V-Twin oil and M1 filter.

If I were in your shoes, I'd be changing the oil/filter before running it again and praying to the mechanical gods to grant mercy on your wallet.

Keep us posted.

blackhawk
07-15-2007, 01:14 PM
I've been told the "rule" for oil pressure is 10 lbs per 1000 rpm to 3000 rpms then a minimum of 30.

But that seems awfully low to me. My boat at start up runs 60+ at idle. And after a long hard run still reads 30 at idle.

The million dollar question is. What does your motor USUALLY run for oil pressure? If you all of the sudden dropped oil pressure I'm with these guys and something is wrong.

Cuda
07-15-2007, 08:21 PM
The 1986 420's in my Formula run about 65 psi at speed, but when I back completely off the throttle, it will drop to about 5 psi for a few seconds, then when I get it just above idle, around 1000 rpm, it will come back up to about 40 psi, and go up to 65 again if I run at speed. I think the oil is foaming. I changed one engine to Mobile 1, and the other with fresh dino oil. It made no difference.

BigGrizzly
07-15-2007, 09:29 PM
With a blower don't run more than 175 degrees in the closed loop system! When it decides to detonate it happens in a hurry. Whose cooling system are you using.? It needs to be what is called a full flow system which means the flow is at the max regardless what the Tstat does. The oil and PS cooler must be before the heat exchanger. You might have to loose the full system and go with the engine only type.

zimm17
07-16-2007, 05:34 AM
Oil pressure has always been screwy on this motor. With my old faria gauges, I had 5 psi at idle, but a mechanical gauge showed 40 at idle when cold. Now I have livorsi gauges and it's reading about 5psi lower than the mechanical gauge. Still too low.

I also noticed that the ECU was running soooo rich I fouled plugs and I also think I thinned out the oil from so much fuel getting into it. I changed the oil and plugs before the next run and the oil pressure picked back up.

So I'll change oil again (castrol 40wt), get the temp gauge in there, and re plumb my cooling system.

Griz- I'm running an seakamp big block system with the big 5" heat exchanger. It was a full system, but I converted it back to a 1/2 system when I went with the blower. I have a 160 deg thermostat, but it runs a steady 190 deg no matter what- idle, full throttle, etc. Maybe I should run without the thermostat and see what it runs at.

I'll re-plumb the cooling water routing. I'll be putting in a sea strainer next week anyway, that'll be a good time to do it. Right now the heat exchanger is first, then power steering, then oil cooler. So I just need to reverse the flow.

Should I go with a bigger 3" oil cooler? They're about $370 for cooler and brackets. I'm trying not to "blow" anymore money on this project.

BUIZILLA
07-16-2007, 06:16 AM
Oil pressure has always been screwy on this motor.
So I'll change oil again (castrol 40wt), get rid of that crap... :boggled:

gcarter
07-16-2007, 06:21 AM
For a larger oil cooler, do a search on eBay.
A bargain is just around the corner.

glashole
07-16-2007, 07:49 AM
I don't want to be the one to say this and i could be totally wrong based on my lack of knowledge but when i was losing oil pressure it was crank bearings etc in the lower end (motor was NFG)

this might be an oil temp thing, or a gauge thing but even with the mechanical gauge I would think you might want more than 10 psi

if you talk to Griz or people who know the oil make isn't as important as the viscosity

that being said when I run straight LUCAS 50 racing oil my oil pressure (mechanical) will be 10psi higher at any given point

I hope for your sake it is an easy issue but catch it early if it isn't and you might be able to save the motor

Shea

VetteLT193
07-16-2007, 08:22 AM
get rid of that crap... :boggled:

I'm with Buiz. If I were in your situation, I'd run 15-50 Mobil 1 or something similar.

BigGrizzly
07-16-2007, 12:02 PM
It almost seems like the exchanger is too small. Run without the
T-stat and confirm this. Mine runs 170. Check the pluming of the cooler it should be just like a car. A big oil cooler is never bad on a blower motor. If you need to talk you have my number, evenings are best.

zimm17
07-16-2007, 12:23 PM
I'm with Buiz. If I were in your situation, I'd run 15-50 Mobil 1 or something similar.

Why would I want a multi-viscosity oil that thins down to 15w at temp as opposed to straight 40wt? Wouldn't that lower my pressure?

zelatore
07-16-2007, 12:58 PM
I think you are reading the multi-vis labels wrong. A 15w50 doesn't 'thin down to' a 15w at temp. A simplified description would be that when cold it flows like a 15w and when hot protects like a 50w. As I said that's a simplified explanation, but it gets the idea accross.

Thats why you'll see multi-vis oils have a broader temperatur opporating range. Look at engine manufacturer's specs and you'll often find they recomend multi-vis oils when you have broad swings in ambiant temps, while single vis oils are specified for narrower temp windows.

That said, I realize you're dealing with a specialized application here and a single weight may be supperior in you situation - I'll leave that to the blower experts. But in normal situations, I definatly lean toward multis.

blackhawk
07-16-2007, 02:10 PM
Why would I want a multi-viscosity oil that thins down to 15w at temp as opposed to straight 40wt? Wouldn't that lower my pressure?

A multi-viscosity oil, like 15W50, has the viscosity of a 15 weight oil when cold and the viscosity of a 50 weight oil when hot.

Multi-viscosity oils are mainly used in autos that have varying climates COLD temperatures(50* is not cold :D ). But, since the new rage is synthetic(Mobil 1, Royal Purple, Amsoil, etc) and these are usually offered in multi-viscosities this is what people think is best.

You ask 10 different people about this and you will get ten different opinions.

Bottom line, IMO change intervals are MUCH more important than the brand of oil you put in. Synthetics are suppose to offer more protection and with your hp it can't hurt. But, there is nothing wrong with Castrol straight 40. It is a high quality dino oil.

BigGrizzly
07-16-2007, 02:18 PM
Zelator is Correct. At STP multi oil pours like the first number and at running temp it protects like the second number. However do not be disillusioned. the straight 50 at running temp does have a little advantage if running temp surpasses the 185 degree nominal temp I don't want to get into this again, but most name brand oils protect about the same providing the API rating is the same or higher. There is nothing wrong with Castrol oils as long as 14w40 is not used!!! never use qa 10w 40 oil regardless of brand. As for Synthetic oil I don't use them except in my air cooled Race bike or transmissions/gear case. You are better off changing it more often. I won't even discuss Mobil vs Amsoil vs Red line vs Spectro. We have done the test we know the answers, and it isn't even worth discussing. There is no record in Nascar, Formula one AMA competition or Cart where oil failure caused a problem it has always been another component. Multis flow at cold start and reach running viscosity sooner. so warm up is faster.

Barry Phillips
07-16-2007, 02:29 PM
My 496 runs 20 psi at idle and 40 psi at 4000 rpm on the hotest days. My closed cooling reads 150 to 160 degress on the dial no matter what the weather is. My raw water cooled small block ran 170 on hot days. Something is wrong. Check the risers after a run, can you touch them? Dose the motor smell hot?

BUIZILLA
07-16-2007, 02:51 PM
I must be out in left field on this..... then again, i'm a CERTIFIED Warranty Station for Borg Warner, Schwitzer / Garrett / Holset / IHI / Yanmar turbo's, ( and I am the ONLY individual between Orlando and Key West to do this) so hey, what do I know :bonk:... any warranty's MUST come through me for my signature per these factory's. In my 26 years doing this, and catastrophic analysis, Castrol GTX and basic has been involved in susbstantially more warranty claim issues than any other oil company out there, combined. BY FAR. At least around here. You put a turbo on my counter that has Castrol used, and it's destroyed, and you can literally smell it across the shop... Castrol SynTec is pretty good however... I can't even begin to tell you how many thousands of turbo's we have sold / serviced / evaluated. In fact, right today, I am embroiled in an oil issue with a VERY LARGE truck dealership, selling / servicing Hino trucks, and a pretty decent fleet of 25 Hino trucks using Amsoil for one dedicated owner.... we are doing oil analysis twice a week, and I get written reports, as recent as this morning. We sample from the bottle and also from the oil filter housing looking for Al, Ca, Cr, Cu, Fe, Pb, Mg, Mo, Ni, P, K, Ag, Na, Sn, Zn, W, A, F, V100...

You would be VERY surprised what we find with so called name brand oils. If you use a synthetic that advertises *extended or doubled* oil change intervals are okay.... don't bet on it.... we just found that the V100 on HD15W-40 Amsoil goes away at 8,000 miles to as little as 12.1 and I have seen one instance of 10.8 recently... 5W30 Amsoil out of the bottle, tests at 11.5 or so.. it just cost one customer a $28,000 engine lesson on this... it's about to cost someone else about $4,000 for a destroyed injection pump, ate every tappet, the main housing, and all 3 cam bearings from poor lubrication... people think woweee we can go 15,000 miles.... whoopeeeee, then they use the same filter for 15,000 miles, and everything clog's up and.... you get the picture.... this particular dealer services well over 1,000 local trucks, and has 3 statewide locations, so I am pretty sure he knows what goes on, and who's full of crap.... we do ALL his injection work, he trusts us emphatically...

wanna do a neato home test, get a frying pan and preheat it to 300*, and pour 6 ounces of your favorite blend in for 15 minutes, and get back to me with your photograhic results...

VetteLT193
07-16-2007, 03:28 PM
I must be out in left field on this..... then again, i'm a CERTIFIED Warranty Station for Borg Warner, Schwitzer / Garrett / Holset / IHI / Yanmar turbo's, ( and I am the ONLY individual between Orlando and Key West to do this) so hey, what do I know :bonk:... any warranty's MUST come through me for my signature per these factory's. In my 26 years doing this, and catastrophic analysis, Castrol GTX and basic has been involved in susbstantially more warranty claim issues than any other oil company out there, combined. BY FAR. At least around here. You put a turbo on my counter that has Castrol used, and it's destroyed, and you can literally smell it across the shop... Castrol SynTec is pretty good however... I can't even begin to tell you how many thousands of turbo's we have sold / serviced / evaluated. In fact, right today, I am embroiled in an oil issue with a VERY LARGE truck dealership, selling / servicing Hino trucks, and a pretty decent fleet of 25 Hino trucks using Amsoil for one dedicated owner.... we are doing oil analysis twice a week, and I get written reports, as recent as this morning. We sample from the bottle and also from the oil filter housing looking for Al, Ca, Cr, Cu, Fe, Pb, Mg, Mo, Ni, P, K, Ag, Na, Sn, Zn, W, A, F, V100...
You would be VERY surprised what we find with so called name brand oils. If you use a synthetic that advertises *extended or doubled* oil change intervals are okay.... don't bet on it.... we just found that the V100 on HD15W-40 Amsoil goes away at 8,000 miles to as little as 12.1 and I have seen one instance of 10.8 recently... 5W30 Amsoil out of the bottle, tests at 11.5 or so.. it just cost one customer a $28,000 engine lesson on this... it's about to cost someone else about $4,000 for a destroyed injection pump, ate every tappet, the main housing, and all 3 cam bearings from poor lubrication... people think woweee we can go 15,000 miles.... whoopeeeee, then they use the same filter for 15,000 miles, and everything clog's up and.... you get the picture.... this particular dealer services well over 1,000 local trucks, and has 3 statewide locations, so I am pretty sure he knows what goes on, and who's full of crap.... we do ALL his injection work, he trusts us emphatically...
wanna do a neato home test, get a frying pan and preheat it to 300*, and pour 6 ounces of your favorite blend in for 15 minutes, and get back to me with your photograhic results...

So, bottom line, what kind of oil do you use?

I don't believe in any of the extended interval marketing. I am with you and could never figure out how the filter played into the long interval... Some of the corvette guys change filters between oil changes, and for me, if I'm going to do the messiest part of an oil change, I may as well blow $25 and do the whole change. Cheap insurance IMHO

I've used Mobil 1 for years, and can tell you at 3,000-4,000 mile change intervals the inside of a 350 Chevy will stay looking like new forever... This is in a N/A car application though:)

blackhawk
07-16-2007, 03:54 PM
There was a HUGE thread on OSO about oils. Putting oil in spoons and heating them with a torch, heating them up on gas grills, etc, etc. :bonk:

Bottom line, change your oil(and filter of course) OFTEN!

Just my $.02

Cuda
07-16-2007, 03:58 PM
Methinks seven wfo runs probably did some damage to your stock bottom end, either bearings or crank journals, maybe both. If the Castrol is as Jim says, it probably made it worse. Two minutes is a long time at wfo, unless the bottom end was built for a race applications. I hope I'm wrong, but I have a bad feeling about this. :(

BUIZILLA
07-16-2007, 04:02 PM
So, bottom line, what kind of oil do you use? depends really, different brands and spec's for different applications I have personal requirements for... I know what I DON'T use though... the new API spec's are pretty tight though with the 2007 emissions laws... I think Rotella T has a Zn problem to deal with... too bad to, since Zn is your friend...

lemme tell ya another neato home test you can do, and I did DO this a few years back ,and it turned me off of Pennzoil/Quaker State, after I lost some rod bearings in two 3hp/ci Buick turbo motors, at 14k for each overhaul ya kinda wanna know what went wrong... take a quart of your favorite oil and put it in your home blender and hit the high speed blend button, and hold it down for 2 minutes, shut it off and watch all the air bubbles... see how long they take to dissipate, might take a half hour, or a half minute... air is NOT a lubricant... this is what crank splash does to returning oil... do this with every brand you can think of, you'll know what to buy, and not buy, after that test... don't tell me how great your oil is, until you've done this test yourself, with your own eyes, then get back to me....

blackhawk
07-16-2007, 04:28 PM
The main I see that I don't like is the oil cooler getting water AFTER the heat exchanger. The oil cooler should get water before ANYTHING else IMO.

zimm I hope your motor is okay but I wouldn't run it HARD again until you have installed a larger oil cooler and have it plumbed so that gets water first.

zimm17
07-16-2007, 06:03 PM
Yup, I'm going to pull the thermostat, replumb the cooler, and change the oil again.

I exaggerated about the 2min WOT time. Probably closer to 30 seconds- I only had a 2 miles bay to work with.

The low oil pressure has been a problem since I got the boat- the blower hasn't made much lower.

So if the lower temp doesn't fix it, it's either bearings or a crappy pump. The engine hasn't made any noises like lifter ticking or anything that would sound like it wasn't getting oil.

The plan all along is to run the motor until it blows or locks up, then put in a nice 502 long block built to run hard.

I'll let you all know in two weeks when I get it back on the water.

gold-n-rod
07-16-2007, 06:04 PM
depends really, different brands and spec's for different applications I have personal requirements for...
With a zig like that, you could be a politician. :wink:

take a quart of your favorite oil and put it in your home blender and hit the high speed blend button, and hold it down for 2 minutes, shut it off and watch all the air bubbles...
No sir, I'm not gonna try that at home. It'd piss off the missus and I'd end up buying her a new blender. :bonk:

BUIZILLA
07-16-2007, 06:12 PM
No sir, I'm not gonna try that at home. It'd piss off the missus and I'd end up buying her a new blender. :bonk: what's cheaper, a $60 blender, or a $16,000 engine??? that was the question posed to me...

Cuda
07-16-2007, 07:23 PM
take a quart of your favorite oil and put it in your home blender and hit the high speed blend button, and hold it down for 2 minutes, shut it off and watch all the air bubbles... see how long they take to dissipate, might take a half hour, or a half minute... air is NOT a lubricant... this is what crank splash does to returning oil... do this with every brand you can think of, you'll know what to buy, and not buy, after that test... don't tell me how great your oil is, until you've done this test yourself, with your own eyes, then get back to me....
So Jim, do you think I might be on to something with the foaming causing the brief oil pressure loss at idle on my Formula? Like I said, I filled one with Mobile 1, and the other with some high quality dino oil, I don't remember which, and I saw no difference in the pressure drop. Like I said, it's very brief, and goes back to about 40 if I raise the rpm to just over 1000.

BUIZILLA
07-16-2007, 07:41 PM
Cuda, I don't know for sure of your issue, but it stands to reason that the very nature of M1 is it's pourability and flowability, which *may* enable it to return to the pan quicker over dino stock... This may be what your seeing, and not a foaming problem.. M1 is a great product, easy to purchase, and prolly the most recognized syn stock out there.

blackhawk
07-16-2007, 09:19 PM
So Jim, do you think I might be on to something with the foaming causing the brief oil pressure loss at idle on my Formula? Like I said, I filled one with Mobile 1, and the other with some high quality dino oil, I don't remember which, and I saw no difference in the pressure drop. Like I said, it's very brief, and goes back to about 40 if I raise the rpm to just over 1000.

Cuda, every boat I have owned has a drop in oil pressure at idle after a long, hard run. Not as drastic as down to 5lbs, but usually down to 20. My water temp gauge also climbs. I figured they went hand in hand. Maybe because the motor is still hot from the hard run then all of the sudden you go from 5000 rpm to 600 and have significantly less water and oil pumping through the motor. Whatever the reason, I ALWAYS run my boat at a high idle(1000-1200 rpm) for a couple minutes after a run.

blackhawk
07-16-2007, 09:22 PM
Yup, I'm going to pull the thermostat, replumb the cooler, and change the oil again.
I exaggerated about the 2min WOT time. Probably closer to 30 seconds- I only had a 2 miles bay to work with.
The low oil pressure has been a problem since I got the boat- the blower hasn't made much lower.
So if the lower temp doesn't fix it, it's either bearings or a crappy pump. The engine hasn't made any noises like lifter ticking or anything that would sound like it wasn't getting oil.
The plan all along is to run the motor until it blows or locks up, then put in a nice 502 long block built to run hard.
I'll let you all know in two weeks when I get it back on the water.

If you're set up RIGHT a 2 minute run shouldn't be a big deal, even with a whipple.

I think you're on the right track. Get the water and oil temps down and hopefully you didn't damage anything.

I have my fingers crossed for ya! :D

mrfixxall
07-17-2007, 12:22 AM
Z cut the old filter open first and check for bearing materal before you waste you time trying to cure your problem..

Barry Eller
07-17-2007, 07:02 AM
Zimm, how many hours are on the engine? Did you install the Whipple on a engine with a lot of hours on it? :confused:
I had 52 hours on my 502 when the lifter bounce ate up my camshaft. I cleaned all the bearings in the bottom, but I decided to go ahead and replace them while the engine was out. I replaced rings as well.
I hope the Whipple didn't "Whip" a tired engine...Sorry...

Cuda
07-17-2007, 08:29 PM
Z cut the old filter open first and check for bearing materal before you waste you time trying to cure your problem..
I was thinking the exact same thing yesterday.

zimm17
08-16-2007, 05:18 AM
Okay, I fixed the oil issue. Took out the thermostat and now she runs around 140 deg water temp and 160 oil temp at cruise. After a 4000rpm run, engine was 160, oil 220. Pressure was a constant 40psi the whole time with Mobil 1 synthetic 20w50. After a full throttle run the water stayed at 160 but oil temp went from 220 to 260. I came down to idle and pressure dropped to 20psi until I let the oil cool after 10 minutes of cruising.

I think with my thermostat in, the engine was always running 190 water temp and the oil temp must have been through the roof.

If I was going to run hard for long periods of time, I'd get a larger oil cooler. Since I only go a few minutes at a time, I'll just make sure the oil cools enough before running hard again.

Oh, and by myself I got a new top speed of 86mph! :propeller:

glashole
08-16-2007, 06:36 AM
you don't want to have to wait to run your boat between passes

if you did cure the problem good for you because the alternative is costly in both down time and money

I would get the larger oil cooler and be done with it

have you tried to switch oil brands
I do not want to start a thread about oil nor do I want anyone to think i know anything about oil

but I was running LUCAS 50 Racing oil in my boat and it seemed to keep the temperature a little lower than the Merc 20/50 I did last oil change

just a thought


have a good one
congrats on the top speed!
86 isn't far from 90..............


Shea

zimm17
09-21-2007, 05:24 AM
Another update in the oil temp saga. During the Hampton Roads poker run last month, I watched my oil temp climb continuously to 290 until I pulled the throttle back to around 50mph. Then it settled a bit. Well after slowing to go under a bridge and getting back on plane, the engine lost power and I checked the temp gauges- 250 water and 290 oil- so she overheated. The cap to the overflow was off (or blown off) and antifreeze all over the place from blowing out the overflow (we were in very, very rough 3' chop at 50mph).

I thought all was lost, but when I started the engine to flush it on the hose, it ran a nice cool 140 degrees?

Well I ordered a 3x18" combo oil/power steering cooler and it shows up today. I'll mount and plumb that up, install the sea strainer, check the raw water pump to see if picked up sand under that bridge (where I learned is 2' deep), and do a compression test and change the plugs. Then I'll be ready for another test run hopefully sunday.

gcarter
09-21-2007, 06:44 AM
I'm anxious to see how the 3" X 18" duplex cooler does. I'm interested in that myself.
I truly believe that if you were to convert to a through transom pickup, it would also help. For instance, you would have more than twice as much water available (the plumbing inside the Bravo gimbal assembly is pretty restrictive).

MOP
09-21-2007, 07:29 AM
Big oil coolers can't be beat but one very important factor is over cooling, this has been covered extensively on a few other boards. It is important to run a Tstat to keep the oil in a proper temp range, most say to keep the oil at about 200.

Phil

BUIZILLA
09-21-2007, 07:36 AM
something else is wrong here

even without a cooler, the oil shouldn't get that hot

me thinks you have a sand accumulation/blockage in the engine block below the freeze plug holes and front water pump ports... this will boil the oil as the water can't cool the lower half of the cylinders properly... when we hard fill our race blocks, we have the same problem... check out this scenario before you buy anything

VetteLT193
09-21-2007, 08:22 AM
I agree with Buiz. Something else is wrong.

The worst thing that could happen is you put a big azz oil cooler on, which keeps the oil temp gauge reading a 'good' temperature, when you really have a big problem somewhere in the engine. That will make it go BOOM :eek!:

MOP
09-21-2007, 09:43 AM
[QUOTE=zimm17;417398]The plan all along is to run the motor until it blows or locks up, then put in a nice 502 long block built to run hard.


Run the 454 like you stole it, buy a 502 NOW build it tough. Winter is coming plenty of time to swap then!

Phil

mrfixxall
09-21-2007, 09:52 AM
Okay, I fixed the oil issue. Took out the thermostat and now she runs around 140 deg water temp and 160 oil temp at cruise. After a 4000rpm run, engine was 160, oil 220. Pressure was a constant 40psi the whole time with Mobil 1 synthetic 20w50. After a full throttle run the water stayed at 160 but oil temp went from 220 to 260. I came down to idle and pressure dropped to 20psi until I let the oil cool after 10 minutes of cruising.
I think with my thermostat in, the engine was always running 190 water temp and the oil temp must have been through the roof.
If I was going to run hard for long periods of time, I'd get a larger oil cooler. Since I only go a few minutes at a time, I'll just make sure the oil cools enough before running hard again.
Oh, and by myself I got a new top speed of 86mph! :propeller:


Removing the thermostat is just putting a bandade on the old problem...

theirs no way a engine is going to run 160 without a t-stat,,Buiz may be rite about this one:confused: also you may have a spun main bearing which will cause excessive heat and low oil pressure..i had a customer take 1/4'' off his crankshaft with the same symptoms,,i told him to drop it off before this happened but he didnt listen and then i got the call and it went like this.


the phone call,,mike, speaking, ( j) about to get my boat on plane and i heard this loud bang,,so i opened the engine cover and say all this oil in the bilge and all i see is oil,,(me)do you see any metal pieces in the bilge, (j) ya! theirs a wrench in the oil. (me)put it back on the trailer and drop it off..

so anyways i was thinking a wrench in the billage so i checked my tol box for missing wrenches and say that i wasnt missing any wrenches..so the next day he shows up with the boat so i open his hatch and yes their was a wrench looking thing in their,,it was a rod...he ended up distroying 4 rods a crank and he put one of the rods through the cam and the lifter valley..

zimm17
09-21-2007, 12:20 PM
Thanks for the glim news. The fact of the matter is I'm not pulling the motor and taking it apart for a "theory" on a spun bearing. You could be right, but if the bearing is spun, I'm going to put in a 502 block to replace it- and the current 454 is going to have to blow or have major problems before I pull it.

The oil cooler just showed up so I'm going to start tackling the install.

So one more shot at getting it running right before the summer is over...

You guys also forget that I'm running CLOSED LOOP COOLING, so yes it does run 160deg without a thermostat- the antifreeze just circulates through block and heat exchanger.

The oil stays cool until I'm running 50+ mph, when the boost starts kicking in, then she heats right up. At least until the un-explained overheat after going under that shallow water bridge- hopefully I'll find some sand in the intake lines.
Well...of to work on the boat- update tonight.

glashole
09-21-2007, 12:52 PM
whats the method to clean out the lines?

is there an easy backwash deal that he could do just to be sure?

zimm17
09-21-2007, 01:38 PM
WOW!!!!! :eek!:

Look what was in my stock oil cooler? No wonder it was running hot....

I'm curious to see if it's my current impeller that shattered, or the remains of an old one that the local mechanic said he removed.

The interesting thing is that these pieces are AFTER my heat exchanger- so maybe they were there before I ever installed the closed loop cooling two summers ago. Or they somehow passed through the exchanger. I'll have to do some more digging.

MOP
09-21-2007, 02:02 PM
It is a wonder it could run at temp at any speed with all that crap in there, I doubt like hell it went through the cooler that stuff was in there before. The tubes are way to small to let anything that size pass, I would grumble at you mechanic. Anytime you trash an impeller it is important to pull the inlet and outlets and to flush it out with the garden hose. I think thing are looking a bit brighter, but if in fact you do have some damage you can contribute it to the blockage.

Phil

VetteLT193
09-21-2007, 02:39 PM
That makes everything make more sense now:bonk:

BigGrizzly
09-21-2007, 04:28 PM
I would very seriously doubt they made it through the heat exchanger. Btw The oil cooler should be before the heat exchanger any way. I probably should not have said that , we mite end up with a labbed prop discussion:wink:!

zimm17
09-21-2007, 04:49 PM
Wel the pieces did make it through the cooler. The steering cooler has about a 1" straight through section so the rubber would go right through. My impeller is ok, so it was an older one that blew apart.

Griz- I am putting the cooler in line first- then the exchanger.

gcarter
09-21-2007, 05:24 PM
Griz- I am putting the cooler the first- the the exchanger.
Good move!
But Phil and Griz are right. The tubes are pretty small and most of these HX'rs are triple and quadruple pass, so the chance of anything making it all the way through is pretty small.
I really like the look of the new cooler. Good luck with it.

zimm17
09-21-2007, 09:02 PM
I don't know the layout of the heat exchanger. The in and out raw water nipples are right on top of each other. I don't know if the rubber bits would have had to pass through the tubes or not. Maybe the impeller parts pre-date the closed loop cooling. that would make sense. The raw water pump goes right to the steering cooler (which has a straight pass through), then to the oil cooler. And I never had the hose off the entire time I've had the boat.

I really hope it runs nice and cool after all of this...

BigGrizzly
09-22-2007, 08:28 AM
Zimm, the straight shot from the steering is not so straight there is a little shelf that can hide small pieces . my guess is the hid in there or in the hose before the exchanger was installed. I hope you lucked out again. Watching gages is an important of high performance stuff. If you were not watching the closed cooling would not have saved you. So bravo on the attention!

Scarab Excell
09-23-2007, 07:56 PM
I would say that the cam bearings are worn, that is very common. I bet the bottom end is still ok. The cam bearing is that last place to get oil

mrfixxall
09-23-2007, 10:27 PM
I would say that the cam bearings are worn, that is very common. I bet the bottom end is still ok. The cam bearing is that last place to get oil

The main and cam bearings are the first to get oil,,the rockers are the last.

zimm17
09-24-2007, 05:31 AM
Zimm, the straight shot from the steering is not so straight there is a little shelf that can hide small pieces . my guess is the hid in there or in the hose before the exchanger was installed. I hope you lucked out again. Watching gages is an important of high performance stuff. If you were not watching the closed cooling would not have saved you. So bravo on the attention!

I was hawking the gauges, but the actual events were more like this... While going at a insane pace following a 38 foot boat in snotty conditions at 60mph:

1) temps are creeping up
2) slow down for low bridge
3) watch 38 foot boat almost stuff bow into bridge overhead from the huge waves
4) brother checks engine while going slow under bridge and notes overflow bottle lost lid and antifreeze is all over the place- I say to keep going, that overflow lid always falls off
5) get on plane, hit throttle and engine looses power- engine temp is at 250, shut down motor, throw anchor, call Tow boat US for a free $581 tow back (I had the insurance). Tried idling a few times and engine temp goes from 160 to 200 in a minute.

On the trailer on the hose, it idled perfect and ran cool and quiet, so hopefully the motor is still ok.

Oil cooler and sea strainer are installed. Waiting on oil filter housing, block adaptor, then I can get the hoses made up- should be up for a test drive this weekend.

Cuda
09-24-2007, 07:00 AM
The main and cam bearings are the first to get oil,,the rockers are the last.

I agree. The next time I see an engine failure due to worn out cam bearings, will be the first time.

BigGrizzly
09-24-2007, 04:15 PM
Zimm, I think you saved it. Don''t worry about the cam bearings, The only failed ones I have ever seen had no oil in it and the all the mains were galled and copper with a broken oil pump shaft. Fx it and go boating.

Scarab Excell
09-24-2007, 04:48 PM
Replace it and run it, you will be back saying the same thing, I have seen alot of Big Blocks without oil coolers run fine, I would love to be wrong but time will tell. And as far as the rockers getting the oil last, the poster is correct but I was talking about bearing not rockers the last bearing /bushing to get oil is the cam and if they are loose you will still have a good motor and the bottom end still gets plenty of oil, it just leaks out around the cam to fast to keep the pressure raised when hot.

Hope you have it fixed.. Good luck.