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Mercruiser_ grinding noise when starting

blaine_barnett

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The problem started after bein

The problem started after being on the water all day with a lot of starts and stops pulling kids on tubes ect.. At the end of the day I went to start it and there was a loud grinding noise when trying to turn it over. Got towed in and was told to check the battery and starter. I replaced both and it still does it.

It sounds like it wants to start for a second and then the loud grinding noise. Any help pointing me in the right direction would be great.
 
New starter bad? How old are

New starter bad? How old are the battery cables? Remove and clean ALL contact points including the block. Check for voltage drop from battery to starter; not more than 0.02 volts; replace if it is.

Could be the slave solenoid restricting the amount of current to the starter solenoid which then can't fully engage the starter.
 
The cables are atleast 7 years

The cables are atleast 7 years old ( I bought it used) but everything looks really clean. I'll look into the solenoid and pull the starter back out and have it checked. When I do that should I be able to move the flywheel to check if it has siezed?? I think I read you can use a screw driver to move it....
 
"I would "jump" the sl

"I would "jump" the slave solenoid (SS) first to see if it works. If the SS studs are blackened it's a good chance the internal contactor is fried. Check the cables with a meter; replace if questionable.

Remove the spk. plugs, disconnect the battery and turn the engine w/a socket to check the flywheel."
 
I think this is bad news...as

I think this is bad news...as I took one of the spark plugs out water drained out of the socket. I don't know what that means but it can't be good...
 
"Pull all the plugs, crank mot

"Pull all the plugs, crank motor,spray some oil in the plug holes but try to get in running as soon as possable"
 
Unbelivable I am having the sa

Unbelivable I am having the same problem I just took the plugs out of my port side engine (V8) and water drained out Is it the risers or manifolds that are leaking into the cylinders.
Does anyone have any ideas?
 
Bt How do u get it running if

Bt How do u get it running if water is going into the cylinders? Won't the water keep going into the cylinders?
 
"Ok..I pulled the starter out,

"Ok..I pulled the starter out, pulled all plugs which had some rust on most. About 3 table spoons of water came out of one socket. I can move the engine with a socket a small amout and it seems to be losening up more as I continue to do it...thoughts??"
 
Blaine Barnett
I'd get s


Blaine Barnett
I'd get some penetrating oil and lubricant in that hole and let it soak for awhile.
Bert
 
Thanks...I got some wd-40 and

Thanks...I got some wd-40 and sprayed it in each cylinder and cranked out the tight spots until I got it to turn all the way around. I now need to figure out how water got in there in the first place
 
"Was unit properly winterized

"Was unit properly winterized last season?

Blown gaskets, warped or cracked heads, or internally cracked manifolds (or even the block) from overheating or freezing are common means water can get into the cylinders. Compression tests are in order to try to detect source, commonly followed by some disassemby for additional tests.

Has it run since the event you described? There is a possibility the noise you heard was from a thrown rod which in turn punched a hole into the water jacket.

Difficult to diagnose over the internet - will require some serios examination. None of the above possibilities will be dirt cheap to fix, so I hope for the best for you."
 
Thank too all. Looks like I ha

Thank too all. Looks like I have some serious and expensive problems here and they are beyond what I can fix. It's a 94 Bayliner 2050 Capri amd I'm not sure I want to drop a couple of grand into it.
I was quoted $500 to pull the heads and diagnose the problems and my gut feeling tells me it would end up costing between 2 and 3 thousand....
 
"remove the drive if possable

"remove the drive if possable or install muffs and remove the inlet hose at the therm. housing.drain block and manifolds, restart engine. it can be run for 15-20 seconds at a time. Longer and you risk burning the rubber items. The idea is to dry the internals (valves,pistons,rings) then fog the engine down untill repairs are made. Most likely a riser failure, so just pull the risers first and inspect them for holes."
 
Water on the piston is usually

Water on the piston is usually a manifold or riser problem. Water in the oil is an engine problem.
 
"No..it hasn't run. I just

"No..it hasn't run. I just killed the engine on the water and it never started again. Could the grinding noise I heard have been the starter ginding on the flywheel?? I think since I pulled the plugs and found the water draining out of one socket... sprayed wd-40 in there and worked the tight spot out until it cranks around I might have had a hydrolock which might explain the grinding noise. I drained the oil into gallon milk containers, it was black but had 1/2 inch of water that settled at the bottom of the containers"
 
"You have some serious trouble

"You have some serious trouble.
With any "luck" it will only be exhaust risers or manifolds.

A water leak into the cylinders thru the exhaust valves will find its way into the crankcase oil, as water wants to run downhill, and quite a bit will leak by the rings. Your block and heads may be fine even though you have water in the oil. Hopefully you did not run it enough to trash the bearings and crank. Was the oil milky at all? If not, you are likely OK, as the water did not get deep enough to get pulled into the oil pump.

I would start by pulling the manifolds and risers and leak testing the water side of them. If you are "lucky" they will be the culprits. If your engine is RWC and in salt water, cast iron manifolds and riser have very limited lifespan; 3-5 years is about it.

Rod"
 
When you get past that stage a

When you get past that stage and back to the starter issue.....when the starter is off and plugs are out you might want to turn the engine by hand watching the flywheel for messed up or missing teeth.Might need a new ring gear....Todd
 
No.. the oil was black and abo

No.. the oil was black and about 1 cup of water at the bottom of the container I drain the oil into. The boat was only used in fresh water and about 3 times a year.

I'm gonna pull the manifolds and risers this weekend....thanks for the tips
 
"Blaine:

W/the risers off l


"Blaine:

W/the risers off look at the exhaust shutters since you are right there. I bet you have a cracked man. or riser. Replace the bolts w/the new parts.
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"
 
I pulled the riser and manifol

I pulled the riser and manifold off one side but I must admit I don't know what I'm looking for. They do have some signs of rust and some flaking but really don't look all that bad. I would expect worse but it's never seem salt water either. Forgive me but how do I test the water side?? The repair manual is really not much help..
 
Is there rust between the exha

Is there rust between the exhaust portion and the water jacket on the milled or gasket ends? A gasket may have failed if there is rust there. Take both sides off and take all 4 pieces to a radiator shop for cleaning and pressure testing.
 
"I have a 500efi mercruiser an

"I have a 500efi mercruiser and there is a loud grinding/metal like noise when the motor turs over. it starts and runs fine. I replaced a start with a new one(old starter had a tooth missing) but now thenoise is still there when starting-nonoise when the motor runs. It sounds like the motor wants to lock up at cetain spots but when I stop trying to start it and turn the key again it makes the noise but starts. I'm thinking coupler, flywheel or alignment? Colud the drive and motor be misaligned? Also pulled the serpintine belt off and checke all the other things for the noise-alternator, water pump, power steering etc and they are fine. Noise still there when cranking even with the belt off. What can I do before having to pull the engine? Any advice ie really welcome."
 
"bill;
You ought to start you


"bill;
You ought to start your own thread.
You will get wider response to your specific problem.

Blaine;
Did the engine run-on after you shut it off at all? If so, it may have run backwards for a rev or two, and this will suck water right up the exhaust Y pipe and right into the cylinders. Just a thought.

Rod"
 
"Gary, either remove the drive

"Gary, either remove the drive or the inlet hose at the therm housing. remove plugs, clear the cylinders, install plugs, re-fire motor with NO WATER 20-30 seconds at a time to dry the cylinders,rings,valves.(run 30 ,wait 60).Fog motor down like for winter storage.
determine water source, make repiars, and then launch,run motor to normal temp. for a couple of hours."
 
Yes...as a matter of fact it w

Yes...as a matter of fact it was starting to run on after I'd kill in engine. What would cause this??

I did pull the manifolds and risers but have yet taken them to be tested. There was a little rust inside but I was told they really didn't look bad and since it was only used in fresh water they should be good. I also started to pull the heads off but got stuck. I pulled all the bolts and took the rods out but the head doesn't want to break loose when I tap it. I'm thinking there are other bolts that I've missed but its kinda confusing in there...
 
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