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mc donzi
04-03-2009, 08:40 AM
Morning Folks,

I bought a 2000-22C with a 454-385 Volvo duo-prop(E4's) last winter in Florida. Computer diagnostics said the motor had 187 hours. On the water test the boat ran 70ish on the speedo. Not sure of the RPM. The Volvo website says that the engine should turn 5000-5200 RPM. Brought it back to Ontario and used it all summer. Never ran it really hard(60ish) because my wife was always with me. Prior to each use I would check the oil etc. and noticed that there was always water in the bilge but I attributed that to the amount of rain that we had over the summer getting into the bilge around the engine hatch. Before I put the boat away for the winter I took it out for one last blast(alone) and all I could get was 65 mph at 4600 RPM.

I took the boat to the marina to be winterized and the mechanic informed me that the bearings were out of the water pump(that accounts for the water in the bilge). The boat never ran above 150F.

My question is... do you think that a bad water pump could account for the drop in RPM and speed??? A new water pump was installed last fall but I never re-tested it because it had already been winterized.

It's been eating at me all winter.

Your feedback would be appreciated.

CHACHI
04-03-2009, 08:47 AM
Dave, you better sell it before you get in too deep.
I will start with an offer of $2500.00 US.

Ken

VetteLT193
04-03-2009, 08:52 AM
65-ish sounds pretty correct for that setup.

I highly doubt the water pump leaking would knock off 5 MPH, but a bilge full of water would kill some speed. Another factor is gas. If you ran the boat on the test run low on gas and no water in the bilge you are talking hundreds of pounds lighter which would knock off a couple MPH for sure.

mc donzi
04-03-2009, 09:29 AM
First things first...

Ken- are you not the "Minxguy" any longer?? Add another '0' to your offer and you can still go to... Methinks you spend as much time on the board as that Morris guy. See you in August.

VetteLT193- The Fla. water test was on a full tank and it ran 70ish- air temp about 80F.The October run was also on a full tank-65mph, air temp about 65F. Bad bearings would cause the leak for sure but I also am wondering if the bearing 'drag' would lower the RPM that much.

Tony Sporer in Detroit has the same set up and his runs 73 on GPS. Mine is injected, his may be carburated- not sure.

Pismo
04-03-2009, 09:40 AM
A bad pump wont cost you 500rpm.

Ghost
04-03-2009, 10:20 AM
I don't think this is all of it either, but does anyone know how much difference to expect with 570ft of elevation above sea level? Is this about right for where you are, or are you down around 250ft above sea level?

(We can also re-live the whole salt/fresh thing again. ;) )

mrfixxall
04-03-2009, 10:34 AM
Did you run the boat in salt water in florida? and now are you running in fresh water? also did the doat sit in the water ? was their crap on the bottom of the boat like alge? boat will run faster in salt water oppose to being in fresh water.any build up on the bottom of the boat will slow you down,did you ever have the props off,prop timing will slow you down..i say when it gets warm out take it for another blast and get back to us..

i dont know why but when i first take my boat out the beginning of summer it always ran faster,2-3 mph..twards the end of summer it seens to run less rpm and mph,my thinking it was the wamer weather and water that slowed me down

BlownCrewCab
04-03-2009, 10:37 AM
Where you driving it in Fla? a differnt driver may have used more trim, less tab & and Fla usually has a good consistant Chop that frees up the Hull some, all these little things add up.

VetteLT193
04-03-2009, 10:56 AM
A bad pump wont cost you 500rpm.

I agree. you'll blow the belt before you lose that kind of RPM or MPH.

MOP
04-03-2009, 11:39 AM
Altitude may be the cause, I belive Tony's boat is the same setup. I will PM him to check this thread.

Phil

BUIZILLA
04-03-2009, 11:51 AM
you may be HIGH on something else


but altitude is not an issue here :biggrin.:

MOP
04-03-2009, 12:02 PM
Jim are you saying that the change from Fla where I think the original testing was done to Canada would not have any effect, has to be a few feet above sea level difference. Or do fuelies not suffer from altitude change?

Phil

CHACHI
04-03-2009, 12:04 PM
Dave,
yes I finally changed my board name. I figured I haven't been a Minx owner for 4 years now. Figured I should change.

You are running the same engine as my '99 22 I can bounce of the limiter almost at will by over trimming.

Simcoe is approx 450 ft more altitude than Lake Ontario. I can't believe that 450 would make a 500 RPM difference.

I also had a bad water pump when I purchased my boat. Still had water in the bilge after I changed it. All clues pointed me to too high of water pressure. Installed a blow off valve and I think I finally have a dry bilge.
When I finally ran the boat with the blow off valve, she was a dumpin' water, per MOP.

I beleive Tony has seen 73 point something out of his boat.

August, might see you before that, you never know.

Ken

Tony
04-03-2009, 04:15 PM
Dave, I remember us talking about this via some e-mails last fall.
I, also, do not attribute the 4600 rpms to the water pump. How about a bad distributer cap, plugs, plug wires, or something along those lines?

I spin 5k rpms at WOT. My 72.8 mph was all alone, low fuel, good tailwind, and good chop. But, even with a full tank and passengers, I still see an honest 70 mph and 5k rpms most any day.

Cherrie and I are hoping for another Lake Muskoka gathering. I think August 14-16 avoids other events, and would likely be good weather. I'm still looking forward to running alongside my boat's twin brother. I bet you'll have your problem diagnosed long before then!

Good luck!

(p.s. Thanks, Phil...)

:beer:

Planetwarmer
04-03-2009, 11:58 PM
Morning Folks,


My question is... do you think that a bad water pump could account for the drop in RPM and speed??? A new water pump was installed last fall but I never re-tested it because it had already been winterized.

It's been eating at me all winter.

Your feedback would be appreciated.

This may sound silly, but I wonder if it is actually running wide open throttle. You may have had it hammered, but I wonder if the cable is allowing it to open it all the way. Or if the computer is allowing it to run WOT. Is the spark arrestor clean? Check to insure the mechanical parts are moving freely in the throttle mechanism. Are you dragging a (or both) trim tab? Are the props tight and moving freely? Does the motor need a tune up (ie plugs, cap, etc)? Check the bearings in the alternator too. If the bearings were out on both, that could certainly account for a signifigant loss in power. I am surprised the bearings are out on the water pump with so few hours. That could be an indicator of the belt being too tight.

Sometimes it is best to check the simple things 1st. They are the easiest things to overlook.

Planetwarmer
04-04-2009, 12:03 AM
Another thing that you may have overlooked is an entire summer of drinkin' beer may have caused some significant weight gain. Could this be the problem?

MOP
04-04-2009, 06:52 AM
Another thought what about the quality or octane of the fuel, did you treat it to 93? I and many others have found that unless the engine calls for 93 many times it hurts performance. I run a 9:1 compression in my 383 on 87 it runs the best, on 93 it loses a couple of mph, there have been several posts relating to that.

Phil

mc donzi
04-04-2009, 12:10 PM
Wow... thanks for all the feedback!!!

Like I said in my original post, I had all winter to think about it and I had considered some of the stuff you guys had mentioned,so I will respond to your ?'s and suggestions in the order that they appear in the thread.

Ghost- Where I do my boating is about 650-700 above sea level and I'm told that that elevation would not impact the performance to that extent. I remember reading about a Criterion with a SBC for sale on Lake Tahoe last summer and how that elevation-7000'+/- would really affect performance.

mrfixxall- the boat was tested in fresh water in Fla. and the boat was on a trailer because the owner did not have waterfront property. Previous owner said that he only ran the boat in salt water once or twice.The boat was immaculate as was his house,yard, cars etc. I know that salt water is more buoyant than fresh and would give better numbers,so that ain't it. The props were removed for shipping back to Ontario and re-installed by a Volvo dealer. Not sure what you mean by 'prop timing'- yer not jerkin' my chain are ya?? We'll leave that up to Chachi!!

BlownCrewCab- I drove the boat but not at WOT-we dropped my wife at the dock and he drove it for the go fast run. When it was bouncing off 70 mph he pointed at the needle in the trim gauge and said that was optimum, so that's where I was running it in October(65 mph) There was some chop(12" +/_) in Fla. but very little in October but I had the tabs sucked right up.

MOP-I doubt if the altitude difference between Michigan and Ontario is 100'... by furlies, do you mean FI's??
Since I've owned the boat all it has had is 87 Octane- marina gas last year was $1.70/ litre($6.50/US gal) OUCH!!

Chachi- I'll certainly be keeping an eye on the bilge to see if there's water after the new water pump. It would be nice to see you'n'Teri before 1000 Islands.

Tony- I got all of the service records from the guy when I took delivery and the stuff you mention had been changed in 2007-08. I'm not sure what's happening in Muskoka this year but if you check Events and Gatherings.. there's a few of us going to the 1000 Islands August 7,8,9.

Planetwarmer-never thought of the cable not allowing true WOT- gonna check that for sure. Flame arrestor is a K&N but maybe it should be changed or at least cleaned- held up to the sun it doesn't look too bad though. Unfortunately beer ain't the problem- 10 years ago though.. I would have had to be a passenger!!

Again Guys...thanks for all the suggestions and I hope that someday we'll meet so that I can put a face to the names.

Dave

CHACHI
04-04-2009, 12:39 PM
Dave, this is getting serious, I was willing to part with $2500.00 US to "save" you from this aggravation. I was presuming everything in the outdrive was fine, pprops out of pphase? This is a whole different can of worms so I will have to ammend my offer to $2500.00 CDN.

Honestly, I believe duo props have to be "in time".

Once again, I will have to defer to Tony.

Ken

mc donzi
04-04-2009, 04:09 PM
Ken,

Dug out my Volvo manual..no mention of the props needing to be in time but will check further.

Regarding your revised offer, I'll pass thanks!!

Don't unbutton yer shirt.. your heart might fall out!!

Later Dude

CHACHI
04-04-2009, 04:40 PM
Dave, this is for a Mercury Bravo III, maybe the Volvo drive is different.

Ken

Ghost
04-04-2009, 10:00 PM
Per this:
http://www.wallaceracing.com/braking-hp.php

Elevation is supposedly costing you about 7.5 HP. Just guessing, but that feels like 1 or 2 MPH to me at most--someone else may know--but feels like a lot less than the loss you've seen. Perhaps a part of what is lost, but not the whole picture. Feels like 1MPH to me. The prop synch thing is interesting.

Planetwarmer
04-04-2009, 11:03 PM
I could certainly see that if the props were installed incorrectly that would cause a problem. If they aren't in sinc, then they fight for the same water and aren't working with each other.

mc donzi
04-05-2009, 07:31 AM
Dave, this is for a Mercury Bravo III, maybe the Volvo drive is different.

Ken


Good lead!!

Can't see why a Merc would be different than a Volvo in a duoprop configuration. Like Planetwarmer said- if they were out of sync, they would be fighting for clean water.

Because of the positioning of the boat in my shop(backed in tight against the rear wall) and a wack of stuff stored in front of the trailer, I can't get a real good look at the props, but looking at them from the side- they MIGHT be off one spline. Not sure how many splines are on the shaft.

In a couple of weeks I'll be able to move some stuff that's in the way and move the trailer ahead, install the batteries so that I can put the drive in trailer mode and have a real good look.

Thanks.

mc donzi
04-05-2009, 07:43 AM
Per this:
http://www.wallaceracing.com/braking-hp.php

Elevation is supposedly costing you about 7.5 HP. Just guessing, but that feels like 1 or 2 MPH to me at most--someone else may know--but feels like a lot less than the loss you've seen. Perhaps a part of what is lost, but not the whole picture. Feels like 1MPH to me. The prop synch thing is interesting.


Thanks for the link- very interesting.

1 MPH here or there isn't much- I'm looking for 5-7.

Like the old saying- 1/2" here or there ain't much, but take that 1/2" and add it to the end of your penis and all of a sudden it's significant.

BUIZILLA
04-05-2009, 08:49 AM
if the props were that much out of synch you would feel a little buzzing vibration... there is an easy way to time the props if you look at the blade and use the blade radius point as a center at 12 for the front prop or 6 o clock for the rear prop and go from there.... some people use the back side of the blade as a center.... I prefer the radius method. YMMV

Tony
04-05-2009, 08:51 PM
Dave, here's a short thread about duo-prop alignment;

http://www.donzi.net/forums/showthread.php?t=46316&highlight=alignment

The one thing you don't want to happen is for the blades to pass each other right behind the skeg.

:beer: