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Merc 57 1986 water ingestion questions

J

jiggamurf

Member
Hi i have a 1986 merc 5.7L wit

Hi i have a 1986 merc 5.7L with an alpha 1. this engine ingested water. this is a freshwater boat i am fairly new to fresh water as ive done only salt water so my first thaught was exhaust manifolds. now engine symptoms are as follows. engine runs roughly and white steam comes out valve covers.. i was only at trolling speed when this happend so engine was not eaven completly warm (according to guague). i stopped engine and when i attepmped to start engine was locked. i brougt back to shop. now if that was the exhaust manifolds the engine would have ran fine am i correct because exhaust would have pulled water in one direction (out) due to the rpm of an engine am i correct. now i pulled the manifolds and risers off to test. they seem to be good but is there an actual test you can do to them?? oh yeah by the way ALL cylinders had water in them. so i figured heads or intake manifold due to water ingestion and steam coming out valve covers correct?? is there a proper way to test intake manifold or the heads?
 
" ALL cylinders had water

" ALL cylinders had water in them. so i figured heads or intake manifold due to water ingestion and steam coming out valve covers correct?"

Not if the water got in from a backwash and got past worn or missing exhaust shutters. The only test I know is to fill the manifold water jacket w/water and see if it leaks out the exhaust holes.
 
"yeah i did that and both mani

"yeah i did that and both manifolds and risers checked ok. so im headding twards intake manifold or heads. i pulled the heads and everything seems to be normal. i dont want to think both heads are cracked and water got into all cylinders on both banks (although it could very well be a possibility) but the chances of that are rare if you ask me. so im checking the intake manifold and as we all know there is one water port on one side of the manifold follwed by 2 intake ports follwed by one center port (wich i dont know if water should be there because wehre that port leads on the head i can see all the way thru and see the exausht valve) then after that center port, its followed by 2 more intake ports and at the back of the manifold the water port is blocked. and it looks exactly the same on the other bank of the intake manifold so im guessing that center port. ill take some pics tomorrow incase i worte it all worng.. thanks"
 
"I would check the shutter val

"I would check the shutter valves as guy stated, especially if it happend at trolling speed, real commen with worn shutters."
 
"i just double checked those s

"i just double checked those shutters and they are i good condition and in place. now let me ask, will the engine still take on water back through the exhaust even in the engine is running? am i wrong to think the rpm are fast enough to not allow water in when exhaust is pushing out?

thanks
Ricky"
 
If the shutters are working th

If the shutters are working then no water should enter thru the exhaust.
 
"nice. can anybody give me any

"nice. can anybody give me any feed back on michigan motorz? i am gonna buy a reman. engine but im am eager to at least find out where water came from on mine. here is another question. if exhaust manifolds, risers, shutters are eliminated we are left with just heads right? and if one head is cracked then water gets in, goes thru center port of intake manifold and gets to the other head wich gives us water in both banks all cylinders right?

any thaughts?
thanks
ricky"
 
that water ingestion link is p

that water ingestion link is pretty impressive i had no clue.

im replacing the engine thanks for your help gentlemen

cheers
 
ok just getting back to this..

ok just getting back to this.. got a new block and long blocked the old one. the new engine is running but when i check timing. i believe initial timing is 8d btdc but i am 11d more than the 8d and when i try to bring the timing to 8d the engine wants to die. is there a possibility i am a tooth off on the dist?

thanks
rick
 
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