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Hotboat
05-07-2000, 06:01 PM
Hey gang, need your help. Just finished a non-Donzi boat that I have been working on for 2 years. A 1972 V-drive Century Mark II with a 340 ci Chrysler. Just totally rebuilt the engine. New everything. Cranked the engine, 60 pounds of oil pressure, after running for 15 minutes(temp 160) 40 pounds of oil pressure. 15 minutes later, 20 pounds pressure. At idle 0-5 pounds. Changed the oil pressure guage, sender, oil and filter. Thought the problem would go away. Took the boat out for a spin yesterday. 60 pounds pressure as I leave the dock, 4 miles later-40 pounds pressure. Started back home to find at 2500 rpm 20 pounds pressure. Let off the throttle coming into the cove where I live, 0 pressure.Idled to the dock, by then the engine was rattling. Pulled the boat out, let it cool off. Cranked it up, 25 pounds pressure but still rattling. Any suggestions or ideas on what happened?

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Hotboat

harbormaster
05-07-2000, 10:55 PM
Eddie... tsk tsk tsk.

Such talk from a guy whose boat won't start. http://206.150.187.82/ubb/tongue.gif

GeneD
05-08-2000, 08:16 AM
One of my buddies just rebuilt a 318 in his RV and the same damn thing happened. No one could figure it out. Right now it is still a mystery.
Hate to ask this, but were the correct bearing used?
How about camshaft bearings?
New oil pump I assume?
I really haven't a clue as to what may have happened, but when you find out, let the rest of us know.

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GeneD
007
Melbourne, Florida

Scott Pearson
05-08-2000, 09:15 AM
Gene is right, check the bearings that were used. The Crank Bearings. If you have a 10 under crank with stock bearing this is what it will cause or a 20 under with 10 under bearings same thing. I had a 302 motor in a 1969 Z-28 and this is exacty what happened. Good luck...let use know how you make out.

(NJ) Scott

Forrest
05-08-2000, 10:31 AM
. . . and always, ALWAYS, use cheap plastigauge to check the bearing clearence on all journals when assembling a bottom end. Yea, it takes an extra hour or so, but going back through the engine takes much longer. Best of luck Hotboat, but by what I am hearing, that engine needs to go back on the stand.

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Forrest

[This message has been edited by Forrest (edited 05-08-2000).]

PaulO
05-08-2000, 10:48 AM
It seems that you now have excessive clearance somewhere on 1 or more bearing surfaces or, you have an oil restriction. The question is; Did excessive clearance create the oil pressure problem or did the oil pressure problem create a bearing clearance problem? Interesting that the oil pressure was 60 lbs at first. I am not a Chrysler expert but, that seems kind of high. Did you have too tight a clearance that hindered oil flow? Was there a restriction in the system somwhere? How about the block? Did you have it cleaned? Is there a possibility of an oil return problem? Give us some more info. What exactly was done to the motor? Crank cut, etc..
Paul

Hotboat
05-08-2000, 06:54 PM
Block was cleaned and magnafluxed, new cam, lifters, timing gears, pistons, and oil pump. The rods were reconditioned and the crank was turned 10-10. I purchased the bearings myself and the box was marked
+ 10. Engine was assembled by a shop that specializes in race engines.

I talked to them today and they seem to think as most of you that it is bearing clearance. I just finished removing the engine and will deliver it back to them tomorrow. Will keep you posted on what they find.

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Hotboat

BillG
05-09-2000, 08:23 AM
I hope that + 10 was a typo, it should be 10 under.

GeneD
05-09-2000, 01:20 PM
Negatory Red Leader.
The crank would be turned down .010 inches, making it .010 undersized, or -.010.
The bearings would then have to be .010 oversized, or +.010 to make up the difference.

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GeneD
007
Melbourne, Florida

BillG
05-09-2000, 03:30 PM
Sorry Gene but to an engine builder the correct term is a 10 under bearing.

GeneD
05-10-2000, 06:59 AM
May be, but doesn't change the fact that the bearing box says +.010. Which is what you said was wrong!

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GeneD
007
Melbourne, Florida

Hotboat
05-10-2000, 09:13 PM
Engine was torn apart today. All the bearings were ruined, even the cam bearings. Crank will have to be turned again. The only problem that was discovered was the bolts that hold the oil pump on were only hand tight. Thinking maybe as the oil thinned and expansion took place, the oil blew around the gasket instead of going up the passage. Possibly the error of the builder. The shop had just placed all the pieces in the washer when I arrived. They will check the block tomorrow for cracks in the oil passages. This is all we know for now. Any suggestions? As for the undersize bearings, yes, now they are really undersized. Down to the core.

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Hotboat

GeneD
05-11-2000, 06:57 AM
This is a bummer.
Sorry to hear about it.
Just goes to show you that even a pro shop can make mistakes.
Too bad you were the one that had to pull that motor.
What is the shop book time on pulling a marine engine?
Is there really a gasket on the oil pump on Chrysler engines?

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GeneD
007
Melbourne, Florida

RickR,GroveCity
05-11-2000, 06:21 PM
Bummer!

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RickR mailto:riggerb@aol.comriggerb@aol.com</A>

Hotboat
05-13-2000, 04:44 PM
Yes, Gene the Chrysler has a gasket under the oil pump. At this point all that has been found is the loose oil pump.

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Hotboat

Hotboat
06-05-2000, 10:56 PM
Engine is now back in boat and running again. Here is what was found. The oil pump had not been tightened, shot peen from the heads had found its way into the cylinders, & the cover over the oil pickup screen had not been removed from the 1st time the engine was built and there was a lot of rust and crud that was lodged and blocking the pickup. The engine never had a chance. Piss poor work from a professional engine shop.Goes to show you that you are better off if you can do the work yourself. The new owners of the shop rebuilt the engine at no charge for the machinings or labor. I had to furnish new parts. Still a costly ordeal.

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Hotboat

AVickers
06-05-2000, 11:52 PM
A "professional" shop wouldn't have screwed things up so bad in the first place. And if they had (screwups do happen, you know), the "professional" shop would have eaten the cost of the parts too, 'cause it was their piss poor work that caused everything to melt down in the first place. And it sounds like it was more than one guy who screwed up in this case -- the head guys didn't clean up after themselves and the guy assembling the engine must have been on drugs.

It's too bad that you have to watch and double-check EVERYTHING that comes back from shops these days. And I don't mean just your engine shop. I mean car dealerships, boat dealerships, mechanics' shops, alignment shops, computer stores, etc. The whole lot of them, it seems.

Oh well, enough of a rant from me. Sorry to hear about your problems and sorry that you didn't get full satisfaction out of those guys... Glad you're back out on the water.

If you find a good machanic, treat him (or her) like gold. They are as rare and as valuable.

Jeeeze!