need big help asap motor down

yea the bilge area under motor was in water bout 3-4" deep when i went to check oil the dip stick was out a little iam hoping it pushed it out dip stick tube.... going to check compression today,,,iam thinking theguy i bought this boat from knew these problems and took me for a ride:smt021
 
Sounds fishy to me. If you had water in the crankcase and in the cylinders and it was in fact locked up, I think you should pull that motor and have it disassembled and have everything checked. The rods on the cylinders that filled with water could be bent, stressed, or cracked and should be mangafluxed and replaced if bad. The rods take a lot of beating and if there was enough water to hydrolock it I would be suspicious. I agree that the PO was probably aware of these issues and just made it look good for the sale. It happens. Don't worry about it too much. Just fix it and enjoy your boat.
 
No offense, find a friend who is a mechanic and let him diagnose. It doesn't sound like you are too familiar with what is going on. You have described the initial problem 3 times, but haven't given any results on the compression test. Water in the cylinder and water in the oil are often 2 different problems. Water in cylinder can cause water in the crankcase after a catastrophic event. Usually water in the cylinder on a boat is riser or manifold leaking back into the cylinder. It can also be a blown head gasket that can not be visually seen with the head on(you stated gaskets look good?) Water doesn't compress like air and therefore it will create so much pressure it will find a spot to decompress. It can bend rods, valves, and crack the block or heads. A compression test will check for valve, and cylinder sealing.
Oil in the bilge can be caused from a crack in the block or a blown gasket. If the pressure in the crankcase builds quickly it could, in theory, blow the dipstick or dipstick tube out.
Is it fresh water cooled, or raw water? Fresh water cooled would have antifreeze in the block, causing antifreeze loss and the cylinders would have antifreeze and not water. A exhaust manifold/riser problem (unless the manifold is cooled with antifreeze) would allow water into the cylinder. The problem is it isn't easy to pressurize a raw water system to find the leak. With a fresh water system I would assume you could pressurize the heat exchanger and check for antifreeze loss( I have never tried, but I guess a pressure tester could be attached to the heat exchanger?)
Do the compression test first and then report the findings. Cranking a hydrolocked engine is never a good thing. You may get lucky, but it usually causes big problems.
 
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k thanks for the replys i have reported took both maniflods off, cant see any visual cracks took heat risers off same thing none of gaskets blowed i got a pressure tester today... going to check heads the guy at boat shop told me some times it will show with test some times not? there was oil and water in bilge area the boat was never started after it hydro-locked... he said more then likely it is a cracked intake,iam going to do pressure check on heads then pull the intake... iam trying to get the guy i bought it from to refund me at least half my money now he says hes broke LOL ...my wife wants to go shoot him he swears he had boat on lake a week befor i bought it with no problems. i was giving him benifit of doubt till i found its not manifolds... if its a intake head or block he knew and he changed the oil was dis-honest and sold it as being a good boat...i should take him to court,prob still wouldnt get anything we saved all summer to get a boat and this is what we get:smt009 will report later anyone on here have a good 350 merc engine?
 
jimjj said:
k thanks for the replys i have reported took both maniflods off, cant see any visual cracks took heat risers off same thing none of gaskets blowed i got a pressure tester today... going to check heads the guy at boat shop told me some times it will show with test some times not? there was oil and water in bilge area the boat was never started after it hydro-locked... he said more then likely it is a cracked intake,iam going to do pressure check on heads then pull the intake... iam trying to get the guy i bought it from to refund me at least half my money now he says hes broke LOL ...my wife wants to go shoot him he swears he had boat on lake a week befor i bought it with no problems. i was giving him benifit of doubt till i found its not manifolds... if its a intake head or block he knew and he changed the oil was dis-honest and sold it as being a good boat...i should take him to court,prob still wouldnt get anything we saved all summer to get a boat and this is what we get:smt009 will report later anyone on here have a good 350 merc engine?
Click to expand...

Did you read replies? First, is it fresh water cooled, or Raw cooled? I'm not sure you will always see a crack in the manifold, if it's down in one of the tubes. What type of tool is he telling you will check the heads? That makes no sense:smt021
If you are refering to a coolant pressure tester, that would mean you have fresh water cooling and are trying to test to be sure that the block and heads are not leaking. As I stated in my earlier post (If you read it) If there was antifreeze in the block and heads there would be antifreeze in the cylinders instead of water, if the block or heads are cracked!
We are trying to help you, but I do not need to know that the owner told you it was on the lake for a week(for the 4th time). Please answer questions and update so we can help
 
the motor is cooled by lake water there is no antifreeze... the test iam doing next is on heads... talked with guy at boat shop he says prob cracked intake going to check pressure on heads then pull intake... the only crack i see on the manifolds are the one on passenger side down in the hole in the center were the riser bolts the fin inside the manifold is cracked he said that would not let that much water into motor? will report back when check heads thanks
 
The #1 reason for a marine engine failure is riser/exhaust manifold leaks. Lets water pour straight into the cylinders through the exhaust valves when there open.
I had milky oil two seasons ago with my small block.
Engine stayed together, With a occasional start up, Lifter tap.
This season, Milky oil again, Replace gaskets, change oil twice. Start Up...... TIC,TIC,TIC,TAP,TAP,TAP,CLANK,CLANK,CLANK, Rocker arms laying on its side now. Still ran pretty good on the Trl. :smt001
A 1985 raw water, Saltwater cooled engine. I wasn't about to patch it. I'm sure it had internal cancer also.
 
k here update guys i checked head compression today left side was all 90 pounds right side front and rear cyl was 90 the 2 center cy lwas 60 pounds. I also noticed the top of intake which is painted black on top of the intake were the 2 center cyl are is rusted on outside top of intake does this spell a cracked intake? also those were the 2 cyl that had pure water come out of them when i removed the plugs... will a cracked intake lower the pressure on those 2 cyl? what is my next step????
 
Intake manifold only has water running through the front and rear. Water would not leak anywhere near the center cylinders. This leads me to believe it's blown head gasket, cracked head, or cracked block in the cylinder wall. Remove the head and have someone who knows what they are looking at inspect the gasket closely. If thats not it get a new motor. I'm afraid any repair you make now will just be a patch. In my opinion Sferg is right, start looking for a new motor!:smt089
 
well now iam really confused the gut at a boat shop told me if the intake was cracked it would let water pour into engine? and if it was a cracked head or head gasket why was it not missing when it was running? the motor seemed fine when it was running... do you really think i need a whole new motor?? and what about the compression numbers does that tell anything?
 
also i looked at a 5.7 vortec fuel injected engine today out of a 1997 chev truck 87,000 would this work for my boat it does not have a intake? what would have to be changed? to go from carb to fuel injection?
 
If you want more out of life then dealing with a never ending broken boat.
Fix it right with good marine parts.
 
jimjj said:
well now iam really confused the gut at a boat shop told me if the intake was cracked it would let water pour into engine? and if it was a cracked head or head gasket why was it not missing when it was running? the motor seemed fine when it was running... do you really think i need a whole new motor?? and what about the compression numbers does that tell anything?
Click to expand...
There is a water passage at the front and rear of the intake manifold (the front runs to where the T-Stat is mounted) If that is cracked internally it can leak into the nearest cylinder runner, which would be 1&2 on the front, on the rear it's just a crossover and is sometimes blocked off with the gasket. It can leak into the 7&8 Cylinders. You are saying that that the engine was running good, but was later hydrolocked? If the cylinder is cracked, and sometimes the beginning of a head gasket leak, It will run fine as long as compression pressure is higher than water pressure. Your compression numbers would indicate that there would probably be some power loss on those 2 cylinders. Please elaborate on "Guy at the boat shop" Is he a technician, or a counter salesman at the local marina store?
As I stated in a much earlier post, Please find a good marine mechanic! This isn't something you should tackle without some guidance.
 
the guy at boat shop is a mechanic not sales,water has been gotten out fresh oil :smt021put in... iam going to pull the intake tommorrow and see what i can see as for allof you saying go buy a 3-4 thousand dollar engine me and my wife saved all summer to buy a boat this was some of her retirement $$$ we are not rich iam trying to fix some one elses lie,iam trying to do this with some direction i have some mechanical exp on cars and trucks not boats it may come to point if icant fix and get some use out of a boat i bought as good no problems LOL.. i may just have to part it out and forget it but would like to get on lake thanks for your help i will updatelater
 
First I would not blame the seller, let's put it in prospective you bought a 23 year old boat and engine without a mechanical inspection of the engine. I would say that you didn't do your due diligence, all this may have been avoided had a compresion test been done pre purchase. Now, the problem is not your intake, you have a well worn motor based on your compresion, the numbers are very low on both sides. If it were just a head or head gasket you would be lower on one side, not low on both sides. I think you have two problems, a worn engine and what ever is allowing water in the cylinders. I thought you said in one of your posts the the exhaust manifold was cracked???

There were many other tests I would have done first, I would have put oil in the cylinders and then recheck the compresion, you could perform a leak down on the cooling system. I would probably just get a rebuilt marine long block (about $1700 with core) and change over everything and replace the exhaust.

I know it may be more money then you wanted, but the upside is you will hve an engine that should last you many more years and a boat that will be more usable. The most important thing is to learn from our mistakes....

FYI: I do not claim to have perfect grammer, but this is not a text message. You will get much better response if you "speak" correctly...
 
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Ihadahardtimefollowingthisthread....punctuation is EVERYTHING!!!

If you cannot afford to fix it right the first time, how will you be able to afford to halfway fix it several times? Parting an older boat out will be a MAJOR loss financially, the market it crap right now on decent boats...much less for project boats.

Sorry this is happening for you, but this would be a great thread for potential buyers of used boats...pre-buy inspections are worth their weight in gold...
 
I can not emphasize the importance of a surveyor when purchasing a boat. A good friend of mine purchased a 48 ft yacht for a "good deal". He had to replace the bulkhead that had dry rot. This part had cost him over 15G! He was the one that encouraged me to get my boat surveyed before I purchased it. I took his advice to say the least on a 23yr old boat. Everything has checked out perfect. Since I worked in a speed shop for many years and I have a lot of experience with engines, I did the compression check and took the oil sample. I’m still waiting on the oil sample test. My compression check showed the engine to have 240psi compression in 7 cylinders, 220 in no 4 (still within 10% margin of error so no worries there). If you would have had it surveyed by a reputable surveyor, you would have found the low compression and other problems.
My point, pay a surveyor to know what you are getting into when purchasing an older boat, $400 is cheap insurance!
 
:smt021you check before and after the demo...then hire a PRO.to inspect then throw a price knowing what the boat will cost you to own NOW!!!:smt021
jimjj said:
questions still not answered read and respond to them not jokes this is serious...... first off there was no water in oil when i checked it when i bought it..... took it to lake ran for 30 minutes..... took it to slip did not try to start it no more that day...... went back to start it next day it would not start........ i was told when water was leaking into oil that it would run till you shut it off...... thats when it will hydro lock.... iam trying to find the problem do you think it could be gasket or cracked manifold???? answer this
Click to expand...
 
With low compressions AND water in the motor I would say pull the motor and have it overhauled or buy one that's already been overhauled.
 
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