Engine Probs..Suggestions??

[CLFouts]

I have a 98 maxum 3000 with two (jasper reman) Chevy 350 motors with thirty hours on them. Port motor runs great; Starboard has given me a fit since I bought the boat. Runs rough , misses, hard starting and now when I had it winterized mechanic says he found 16 qts of fluid (water oil mix) in the oil. So I know this could mean possible head gasket (worried about water in engine). I don't know how long the motor has been like this since I purchased the boat last year. Been quoted 6 hours labor to remove the motor and 1 hour to diagnose it. Just trying to figure out if this motor is even worth repairing. any suggestions?

[mrt214]

Water in oil is never good and the possibilities how it got there are numerous.
Compression test will tell if you have a bad head gasket but it could also be a cracked block. Once the heads are pulled you can look at cylinders to check for cracks. No matter what you find as the problem, unless you are doing this yourself, bring lots of moolah. May just be cheaper to replace motor.
Good luck.


Bring Out Another Thousand

[shrew]

How did the manifolds look?? cracked/corroded cooling passages and failed gaskets can occur here as well.

[CLFouts]

Don't know yet.. haven't pulled engine just yet.

[Kevlar7r]

You don't need to pull the engine to pull the exhaust and inspect. Failed exhaust is the most common source of water in these engines.

The 3000 has a screw head for the hatch cross member right over the carb of the starboard engine. If that screw is not sealed, rain water can drip into the carb.

If it were my boat, before pulling the engine, i would replace exhaust, change oil, change spark plugs, fuel filter, and possibly rebuild carb, then see how it ran.

If there is still an issue, or if you get new water in after that, then I would pull engines.

[Kevlar7r]

Also, all of the things I listed doing would transfer over to a new motor if you ended up replacing, so you wouldn't be throwing money away.

[CLFouts]

What do you mean screw head? Is there a way to pull the fiberglass top off of the motor to gain access?all has been done except replace exahust.

[Kevlar7r]

I mean the screws that hold the cross member to the starboard of the engine hatch. The one that supports the front edge of the ice chest drain area.

Before you do anything else, change the oil. Then change the exhaust, run it, and see if more water comes in to the oil.

[CLFouts]

Thank you for the info.

[mmwjr]

First of all no way it was 16 quarts but that doesn't matter water in the oil is bad. What do the spark plugs look like?

I would do a compression or leakdown test before spending money on exhaust. Then block off the coolant passages external on the engine with a pressure gauge and pump up to 10 psi to see if the pressure holds or not. Then you will know if major issues exist.

[CLFouts]

Well, found the problem. Bent push rod, Valve and bad head. These motors I think have little more than 30 hours on them. I am having a new long block installed, Hopefully no more issues. It was the exhaust valve so that is where the water was being drawn in from.

[mmwjr]

Originally Posted by CLFouts

Well, found the problem. Bent push rod, Valve and bad head. These motors I think have little more than 30 hours on them. I am having a new long block installed, Hopefully no more issues. It was the exhaust valve so that is where the water was being drawn in from.

The bent push rod and valve are not the cause of the water but the result of water in the cylinder which caused them to bend as water is not compressible. What is bad with the head? Crack, wrapped? Replacing the longblock? Is the other one damaged? Are you replacing the head?