Siezed 5.7 teardown

[idahoelk]

Boat: 1994 Blue Water Marquee, 22' BR
Engine: 5.7 Mercruiser SN#
F145617
Casting# 14093638

Problem: Siezed motor (water in #6 & 8 cylinders)
potential cause: not winterized in time:facepalm: two daughteers got married within weeks of each other:eek:, port exhaust manifold has a 6"+ crack in it, starboard manifold may have small cracks by bolt holes

there is rust in the #6 & #8 exhasut ports on the head, the remaining exhaust ports on the heads do not have rust.

i have stipped the engine down to the heads and am ready to pull them. the question I have is do I have to remove the push rods prior to removing the head? i have loosened all of the head bolts but it will not budge. I know I am not to use a prybar on the mating surfaces as this will cause marring of the surface and lead to further problems. The head will not budge.

This engine has been apart before as you can tell from the pictures below with the heads designated R & L in metal marker. from the looks of the intake bed, the previous install included black RTV, I had to find a lip onthe intake that I could tap to break the seal on the intake.

Also, which manual should i try and find for this motor and whre can I find it? Thanks.

 

[Bt Doctur]

Re: Siezed 5.7 teardown

all 17 bolts? then just stick a pipe into a port and tap upward. manual might be 17

 

[idahoelk]

Re: Siezed 5.7 teardown

Thanks Bt Doctur, I missed the ones under the rocker arms.

I now have both heads off, sprayed all 8 cylinders with penetrating oil after 20 minutes I could crank the engine with a ratchet. Wiped all the walls with penetrating oil and am now at a decision point.

When I drained the oil there was no water in the oil at all. It makes me think the water in the cylinder came in through the manifolds. No water intrusion on the starboard side at all. Starboard exhaust manifold had 6"+ external crack in it.

Do I go ahead and remove the pistons and re-ring them since I am this far, put it back together and compression test it, get it done and go play on the water? Definitely want to do the last one, but also want to do it right.

Thanks.

I have had the boat for 5 years and this is the first major work that has been done on it.

 

[Fishermark]

Re: Siezed 5.7 teardown

Those rust stains in the cylinders - can you feel them with your fingernail? The choice is yours of course. If it were me, I would take it to a local machine shop and have them measure the bore and evaluate the corrosion in the cylinders and go from there.

 

[Bt Doctur]

Re: Siezed 5.7 teardown

i would atleast drop the 2 clylinders that were wet to check the rings.

 

[Fishermark]

Re: Siezed 5.7 teardown

One more thing - just because there was no water in the oil doesn't mean the block isn't cracked. You would need to run it more than likely for water to get in the oil.

 

[idahoelk]

Re: Siezed 5.7 teardown

Pulled all 8 pistons. Rings look good except on #6 the top ring is compresses and will not open or spin. The rings on all the other pistons move freely and opened well when they cleared the cylinders. Should I replace the whole set or just on 6?

 

[lineman09]

Re: Siezed 5.7 teardown

Pulled all 8 pistons. Rings look good except on #6 the top ring is compresses and will not open or spin. The rings on all the other pistons move freely and opened well when they cleared the cylinders. Should I replace the whole set or just on 6?

if it were me and i had gone as far as you have, i would go with a complete ring and bearing kit or a complete rebuild, why mess with it again, you have the motor apart..... mite as well do it right...

 

[270win]

Re: Siezed 5.7 teardown

if it were me and i had gone as far as you have, i would go with a complete ring and bearing kit or a complete rebuild, why mess with it again, you have the motor apart..... mite as well do it right...

agree with this, do it once, do it right and be done...then winterize early!

 

[idahoelk]

Re: Siezed 5.7 teardown

That is the direction I was leaning once I got this far. After seeing the stuck ring on #6 i figured I might as well look at the rest of them it was only a few more minutes work to pull them. I am going to contact the macnine shop on Monday to see if they will magna flux it for cracks just to be safe. Do I need to pull the crank and cam for that or will it be ok to leave it on? Barry's should be able to tell me that also.

Where is the best place to get a ring and gasket kit? I checked on here, but could only find rings for individual pistons no kits. Also how do I free up the ring on #6 to get it off? Is is squeezed down to less than 1/16" gap between ring ends and I can't get anything in there to pry it apart. I'll soak it in penetrating oil overnight and hope it loosens by tomorrow.

Really hoping to watch the fireworks from the boat this year...gonna be some late nights this week.

Oh and by the way, no weddings to distract me on the winterizing this year :redface:

 

[Scott Danforth]

Re: Siezed 5.7 teardown

get the parts thru your machine shop. their prices should be comparable to summit racing, etc, and they may have them in stock.

 

[270win]

Re: Siezed 5.7 teardown

Don't order anything until you know what you need. If the cylinders need to be cleaned up you may need pistons too. I would tear down the rotating assembly and remove the cam and have the machine shop re-assemble the short block at least.

 

[idahoelk]

Re: Siezed 5.7 teardown

Just picked up the block, heads, crank, and cam from the machine shop. No cracks to be found. He surfaced the heads and block, polished the crank and checked the cam. It is ready to go back together.

I have one exhaust manifold with an external crack and one manifold with an internal crack (showed up in the acetone test and was responsible for the water in the #8 piston) I have two manifolds on order from the local boat shop.

I have been trying to find links to manual 17 but have not had any luck. can anyone help me out with this?

1994 Bluewater Marquee
5.7 Mercruiser

 

[waterdawg60]

Re: Siezed 5.7 teardown

I do have the #17 manual if u want it can I just insert it some how, sorry techno peasant...lol

 

[idahoelk]

Re: Siezed 5.7 teardown

Thanks everyone for the help. Waterdog - many thanks to yhou for sending me the manual. I dropped her in the water this evening and she fired right up (after spending an hour this afternoon with the local mechanic getting it timed). starts better than she has in five years.

Only one MAJOR problem - my coil is arking to one of the side terminals on the coil. I have tried uploading a video of the spark but cannot get it to play on you tube. the spark is bright blue and is arcing across a good 3\8" gap. The motor runs well, but i have to fix this sparking issue...we all know where that could lead otherwise.

Any ideas?

I am going to run this on it's own thread here: http://forums.iboats.com/showthread.php?t=564909&p=3878659#post3878659

 

[Fishermark]

Re: Siezed 5.7 teardown

Coil sounds cracked - replace it.

 

[idahoelk]

Re: Siezed 5.7 teardown

Replaced cool and no more arcing. Have had the boat out 4 times and she ran great, a total of about 5 hours. See new thread with latest issue. It titled sudden oil pressure drop.