Water ingestion motor problem need help
- Thread starter Aponte
- Start date
PlayDate
Well-Known Member
This is the exhaust modification for the 310. It's hard to believe that Sea Ray would have sold the boat with the original design:
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Aponte
New Member
John what do you think about the compression...Anthony
- Nov 26, 2006
- 7,628
- Boat Info
- 2008 44 Sedan Bridge
- Engines
- Cummins QSC-500's
Straight Drives
Aponte,
Do these pics reflect damage over time? It appears to. I always assumed that water ingestion would be catastrophic.
Do these pics reflect damage over time? It appears to. I always assumed that water ingestion would be catastrophic.
PlayDate
Well-Known Member
The most accurate test is done with the engines warm and a screw in tester. A cold test usually leads to low numbers. Your engines warm should be north of 160-170 lbs per cylinder (with no more than a 10% deviation). You have a compression ratio of 9:1.
I just checked the specs for your engines and the 125lbs indicates real problems even if the engine is cold. The next step (even without a warm test) is to pull one of the exhaust manifolds off and check the exhaust valves. That will clearly tell you what possible problems exist. Low readings like this indicate internal damage (cylinder wall scoring and/or valve damage).
-John
I just checked the specs for your engines and the 125lbs indicates real problems even if the engine is cold. The next step (even without a warm test) is to pull one of the exhaust manifolds off and check the exhaust valves. That will clearly tell you what possible problems exist. Low readings like this indicate internal damage (cylinder wall scoring and/or valve damage).
-John
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PlayDate
Well-Known Member
Hampton, most water ingestion to your point is catastrophic. Usually a failed gasket, exhaust component, extensive cranking (especially on generators) causes a stream of water to find its way back down the manifold into the exhaust valve opening. Aponte's situation is more interesting because it doesn't appear to be a component failure. Rather, a continual buildup of moisture. Several things can cause this. Certainly the height of the riser/spacer can create a significant temp differential from the engine manifold. It can also be pinholes in the spacer/riser or elbow.
I know Sea Ray and Mercruiser have fixed this problem. I just don't know why they haven't got it right on Aponte's boat.
-John
Sublimetime
Active Member
Water ingestion and water reversion are two different things. APONTES low compression may be caused by a rusty seat or rusty valve stem,either way its closing but not sealing.Most likely caused by 7.4 mpi motors tendency to reverse exhaust mist and condensate.This is what you see collecting inside his spacer/and risers.It collects,it rusts,it flakes away,collects in the bottom of exhaust port in the manifold,and provides perfect enviroment for humid add to collect on open valve seat and exposed bare stems. I've" been there and done that".
INGESTION is when severe leaks occur at joints or rust holes thru and sea water is sucked directly into cylinder.(at least thats what I thought)
INGESTION is when severe leaks occur at joints or rust holes thru and sea water is sucked directly into cylinder.(at least thats what I thought)
Aponte
New Member
Also this past Jan valve Jobs on both eingines were also done. will be out of toen for a couple of days. will check back next week with more updates from marina..Anthony
PlayDate
Well-Known Member
Anthony,
Here are the links detailing the problem we discussed on the phone. You might want to have your attorney contact Boat US Consumer Affairs to get some more background info on this issue. I do not have a copy of the original Mercruiser Bulletin but the synopsis reads:
"In August 2001, MerCruiser issued service bulletin 2001-13, "Gasoline Engines and Water Intrusion," which states that under certain conditions a fine mist or water droplets can be drawn backward into the exhaust passage of the exhaust elbow when the engine is idling. The droplets wet the vertical exhaust passage, and when the engine is shut off, the droplets fall and collect in the exhaust manifold runners that go to the cylinder head."
http://my.boatus.com/consumer/EngineBlocks.asp
http://my.boatus.com/consumer/poweroutage.asp
-John
Here are the links detailing the problem we discussed on the phone. You might want to have your attorney contact Boat US Consumer Affairs to get some more background info on this issue. I do not have a copy of the original Mercruiser Bulletin but the synopsis reads:
"In August 2001, MerCruiser issued service bulletin 2001-13, "Gasoline Engines and Water Intrusion," which states that under certain conditions a fine mist or water droplets can be drawn backward into the exhaust passage of the exhaust elbow when the engine is idling. The droplets wet the vertical exhaust passage, and when the engine is shut off, the droplets fall and collect in the exhaust manifold runners that go to the cylinder head."
http://my.boatus.com/consumer/EngineBlocks.asp
http://my.boatus.com/consumer/poweroutage.asp
-John
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PlayDate
Well-Known Member
Here is the link to the original Mercruiser Bulletin......a must read:
substitute b o a t f i x for the asterixs
http://www.*******.com/merc/Bullet/01/01_13.pdf
To the forum manager:
CSR blocks that url name. I tried to attach it from my computer and the file was larger than 19kb limit. If there is another method to post pdfs especially Mercruiser Bulletins, please let me know.
-John
substitute b o a t f i x for the asterixs
http://www.*******.com/merc/Bullet/01/01_13.pdf
To the forum manager:
CSR blocks that url name. I tried to attach it from my computer and the file was larger than 19kb limit. If there is another method to post pdfs especially Mercruiser Bulletins, please let me know.
-John
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