Low Compression Problem

[Gary H NC]

Re: Low Compression Problem

Good luck! let us know what you find.

You will find out there is a great bunch of people on this forum.
And Don S is one of the best!

 

[mochosla]

Re: Low Compression Problem

So, I took the boat to a mechanic and he confirmed that the motor is in bad shape and needs to be rebuilt. My questions to you are:

All mechanics I talk to estimate 5K to rebuild it. However, I can buy a rebuilt MARINE motor at Pep Boys for $1700 (one year waranty no limit on ussage) and I can put it together myself. Do any of you have any feedback on Pep Boys motors?

I also found a NEW MARINE motor in e-bay for $3500 + shipping. Here is the description of the new motor:

It comes complete with the following :
New sheet metal,New Harmonic Balancer, New Mechanical Fuel Pump
New Ignition System, Marine 4bbl Rochester Carb, New Fuel Line,
New Spark Arrestor, New Flywheel, New Spark Plugs, New Circ Pump.
New 4bbl Intake Manifold.

This is is completely Dyno-Tested and ready to go !!
Manifolds and riser can be added at additional cost.
Starter and alternator available also at additional cost.

I'm just having a hard time wrapping my head around $4500 to $5000 to rebuild my motor when I can do it for so much cheaper.

Any help will be appreciated!!

Thanks.

 

[mochosla]

Re: Low Compression Problem

Thanks

 

[Don S]

Re: Low Compression Problem

Your marine mechanic will probably do a good job of the rebuild. your pepboy motor will probably just make it past warranty. Even if it doesn't, they will tell you how it's your fault. Probably overheated, Yada Yada Yada.
Get the cheapest you can find. Then in a year..... If it makes it that long.Let us know ALL the problems you had.

 

[Gary H NC]

Re: Low Compression Problem

Brother in law bought one from these folks about 3 years ago...still running strong.


http://www.ebasicpower.com/engines/eagle/eaglebase350.htm

 

[mochosla]

Re: Low Compression Problem

What do you guys think about the new motor. Check it out:

http://cgi.ebay.com/ebaymotors/350-...tegoryZ50442QQihZ014QQitemZ330074046762QQrdZ1

Thanks.

 

[Gary H NC]

Re: Low Compression Problem

With shipping your paying about a grand more than the one i give you the link to.Granted,your getting a new carb and distributer with the ebay engine,wires and plugs...but is that worth 1000 bucks more?...Both are new engines not remans..

 

[mochosla]

Re: Low Compression Problem

The problem is that I don't know how to set the timing right and also don't know how to set the carburation. My carburator needs to be replaced as, according to my mechanic, is not a marine carburator.

Do you have any helpfull links to set timing and carburation?

 

[Don S]

Re: Low Compression Problem

The problem is that I don't know how to set the timing right and also don't know how to set the carburation. My carburator needs to be replaced as, according to my mechanic, is not a marine carburator.

Do you have any helpfull links to set timing and carburation?

Why don't take your boat to a local Marine Mechanic? That's what they do for a living.

 

[Gary H NC]

Re: Low Compression Problem

Don is right,
by the time you get the new engine and have it put in and everything hooked up and adjusted you may as well have a local shop do it for you.Have your local mechanic give you a price on a new long block verses a rebuild.Anyway now is the time to do it.Don't wait untill spring or your local guy will be covered up with work.
Everyone waits untill right before boating season then wants their boat fixed fast.Most shops can't do that and your boat will sit while all the small jobs and spring tune ups ect.will go thru the shop first.
If your not comfortable trying to set timing and adjusting carbs you better not try an engine swap and drive removal.
Just my 2 cents worth..8)

 

[mochosla]

Re: Low Compression Problem

Hi Don, I feel comfortable installing the motor and get it running. I just don't think I can tune it like my mechanic would. I spoke with him and we agreed that I will buy the motor you recommended me, install it and get it running and he will time it and get the carburetion right.

He is a cool guy.

Thanks for all your help.

 

[1978 century]

Re: Low Compression Problem

yea if u got cyclinder next to each other proll a head gasket...the rattling is prolly timming ....make sure your timming is perfect if not u can blow a head gasket even check the total timming....also use atleast 89 octane gas the gas now suck because all the **** they put in it.. i had a prolbem like that with my boat it was pinging head gasket poped cuz the timming ..milled the head complete tune up new springs and weight for the dist. set timming and the engine shop that milled the head said to use 93 gas..i did alll that and prolly put on a good 50 hrs last summer with no prolbems

 

[car5car]

Re: Low Compression Problem

Here is plan:
What is wrong?
Parts
Labor.
Here is what I would do:
Run engine (10 min 2000 RPM no load) with quart of ATF to make sure rings are clean (it will also help to deal with clean engine while fixing it and clean lifters eliminating lifter noise), replace oil.
Check compression.
Add some compression additive, it can take care of compression problem for next 5 years sometimes.
Check compression.
About knock. You need to know if it is valve or crankshaft noise. Let mechanic listen. Make sure to tell him you will not ask him to do the job so he will not lie to you. Pay him for consultation.
After you know problem:
Crankshaft- replace bearings
Valve train noise- lifters rockers pushrods- locate cylinder and valve (stetoscope- 15 doll), open cover, start engine if oil is coming to each rocker arm
Piston noise- replace pistons or some shops make grooves in them pushing metal out increasing size.
Worst case scenario about compression replace rings rebuild heads.

 

[car5car]

Re: Low Compression Problem

Chain noise- replace chain and sprockets.
Check oil pressure.
99 % of replaced engines did not need to be replaced.

 

[car5car]

Re: Low Compression Problem

So, I took the boat to a mechanic and he confirmed that the motor is in bad shape and needs to be rebuilt.

Thanks.

Good machanic would tell you exactly where problem is. Advice to replace engine you could get from old lady living in house next to yours. Go to guy who fix engines. 99% of mechanics don't.
I had engine knock once nobody could recognize it. I don't blame them. Connecting rod was bent and piston was touching crancshft. Very unusual case. Most noises take 5 sec to recognize for engine guy. Good luck!

 

[Gary H NC]

Re: Low Compression Problem

So, I took the boat to a mechanic and he confirmed that the motor is in bad shape and needs to be rebuilt.

Thanks.

Good machanic would tell you exactly where problem is. Advice to replace engine you could get from old lady living in house next to yours. Go to guy who fix engines. 99% of mechanics don't.
I had engine knock once nobody could recognize it. I don't blame them. Connecting rod was bent and piston was touching crancshft. Very unusual case. Most noises take 5 sec to recognize for engine guy. Good luck!

:%:%....5 seconds to diagnose...thats one heck of a engine guy...he must be phsycic...:^

 

[whywhyzed]

Re: Low Compression Problem

holy schmolly - how long is this thread?... I ain't reading all that...
I just want to say - How are we sure the rattle isn't say...
worn ball gears.
Checked your intermediate oil level lately? Upper?

 

[mochosla]

Re: Low Compression Problem

Okay, I just want to give you all an update. I'm replacing the motor with a rebuilt engine from this place in NY. They give you 8 year warranty!. I wanted to buy a new engine but unfortunately they don't have the motor I need anymore. They only offer rebuilt. even in the website Gary gave me above they don't have it. I would have to make some modifications and I don't want to get into that.

The place I bought the engine from recommended I use an aluminum intake manifold. What do you guys recommend?

 

[Don S]

Re: Low Compression Problem

I'm replacing the motor with a rebuilt engine from this place in NY. They give you 8 year warranty!.

Never heard of 'em, or an 8 year warranty on a boat engine.

Remember, if it sounds to good to be true, it probably is.
As far as the Aluminum manifold.......... If you go into salt or brackish water then forget the alum manfold.

I would forget that company from the sounds of things. Buying from the cheapest bidder means you get a warranty that isn't worth the paper it's writen on. And I have seen it happen more times than I care to talk about.
Most of the cheapies have a way of always turning a warranty claim into your problem, so it won't be covered.

 

[mochosla]

Re: Low Compression Problem

Thanks for your advice Don. I followed it and bought instead this engine:

http://www.michiganmotorz.com/5.7L+Vortec+marine+engine-SILVER+Package+(1967-2007+replacement)


They seem to be a reputable company. The other one you recommended did not have the motor.

I will try to install the motor this weekend. However, there seems to be corrotion on the bell housing and I may have to replace it.