Offshoreonly.com - Sick 454 Mag need some advice

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Quote:

Originally Posted by cableguy1979 (Post 4636002)

I have a 454 mag mpi and i have a blown head gasket. Does anyone know if the gasket set at Autozone will work? I need a complete top end kit so i can replace my head gaskets.

are there any differences in a marine gasket set and a standard set?

How did you come to this ? compression test ? or ?

BTW: Thanks for skipping my question. Doh.

Quote:

Originally Posted by bck (Post 4635886)

You can always try Facebook and pick the answers you like from the thousands of qualified people who will respond.

So many true experts there that it has put me out of business. Everyone that owns a boat can fix everyone elses boat no matter of the app without even looking at it in person nor never even sat in one OEM training course nor do not have any service manuals nor proper tools -- not even a scan tool either. Man I wasted so many years with training classes and buying 50 K worth of service manuals plus in the tens of thousands of marine service tools. If only FB was around in my prime I would be 10 times as smart as I am now.

What a huge f in Dart board that has become. The board is about the size of the earth to be exact. Jack of all marine apps master of NONE.

Sb the water got in from the sending unit it was missing a screw. I found out the water line was up to the oil pan. So it didn't compromise the electrical....i don think.

I recently did a compression test and I have some weird results. First i believe my compression gauge to be wrong or off. I tested another known good boat engine and I get the same results. I haven't had a chance to do a compression test on all cylinders. i pulled all the spark plugs out and every cylinder on that side has water in it and lots of it. When i do the compression test the water is causing skewed results as the water makes the compression go up to 150 but all other cylinder on the other side are around 103 just like in the known good engine, when i remove the water. Again i believe the compression gauge to be the culprit for a low compression reading. Ill have to get another and retest.

SO how do you get water in all cylinders on that side? i wouldn't think a head gasket would allow water on all four cylinders. It there a way water can get through the exhaust riser filling up the exhaust manifold and leaking into the cylinder through the exhaust valve? ? All four cylinders on the same side. Not just a little bit of water. I would think i would have very low compression for a blown head gasket. When i put air back into the cylinder I hear bubbling in the exhaust flap. of course there is water in the oil now as I assume its passing through the rings. Complete milkshake.

Exhaust leaking typically.

Hopefully you didn't bend a rod...but quite possible....water doesn't compress.

Was this a salt water boat ? If not, sure your friend is being truthful in this answer ?

I'm sure he's not. But it runs great. Gonna look into the exhaust.