Water on the Starboard side 7.4 mpi.

Dave-R

Chief Petty Officer
Joined
Mar 18, 2008
Messages
441
Hello all: I just bought a used 1999 Chaparral 2130 With a 7.4 mpi duoprop. I knew it had a seized engine when I bought it. first I pulled the exhaust risers and manifolds. The port side looked like it had water in it. The starboard side just looked like carbon. I pulled the port side head off. Not hardly any rust at all. I was able to free the engine after soaking it with Marvel Mystery, and using an air compressor. My Question is, any Idea why the one side would have water and not the other. All gaskets including the head gasket looked good. The riser gaskets looked good on both sides also.
Are there shutters in the exhaust?
As always thanks Dave R
 

skydiveD30571

Lieutenant Junior Grade
Joined
Feb 13, 2012
Messages
1,042
Re: Water on the Starboard side 7.4 mpi.

Volvo quit using shutters in '99 so depending on the year of your engine (boat year doesn't matter) you may or may not have them.
 

Walt T

Lieutenant
Joined
Mar 16, 2002
Messages
1,369
Re: Water on the Starboard side 7.4 mpi.

Replace the manifolds and risers if you don't know how old they are. Have you started the engine yet? I'm interested in knowing how it runs and sounds.
 

Dave-R

Chief Petty Officer
Joined
Mar 18, 2008
Messages
441
Re: Water on the Starboard side 7.4 mpi.

Walt: I'm waiting for the new head gasket set and the new riser gaskets, before I can re-assemble. I am surprised how good the cylinders look. I touched just a few spots up with some 600 grit emery. No water in the oil, and it seems to rotate fine. I actually think the Marvel oil worked the rings loose. We had been soaking it for days. On the Volvo engine, the water pump shaft prevents you from using the crank bolt to break the engine free. We had been trying to use the starter to do this. I have an air compressor blowgun with a rubber tip, that I
used on the side that still had the head on. I found a cylinder that both valves were closed and put the air to it at 90psi and told the wife to try the key. I learned a lot right then. When she broke loose and the exhaust valve opened, all the WD 40 and Marvel oil came right out the exhaust manifold, and all over me. Wife was all smiles. I will keep you up to date. Dave R
 
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Walt T

Lieutenant
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Mar 16, 2002
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1,369
Re: Water on the Starboard side 7.4 mpi.

:) Yeah I've done a few things like that over the years
 

Dave-R

Chief Petty Officer
Joined
Mar 18, 2008
Messages
441
Re: Water on the Starboard side 7.4 mpi.

To keep you all informed on my revival of the seized Volvo 7.4 , I finally got all my gaskets and new gimbal bearing installed.l installed the head, and both exhaust manifolds, and risers. I hated the new Volvo design riser gasket. Looks flimsy for 32$.At 63 let me tell you packing the head up a ladder was all I could do. Everything on the motor is heavy, and horrible to work on.No wonder boat mechanics are grouchy. Well I finally got ready, and primed the fuel injection and got up enough courage to light
her off. Bingo took right off. At first she made a little ticking noise, but it stopped after a few seconds. Probably due to no oil for months. I let her run awhile, checking the oil for water. everything sounds real good. I will need to get her timed, but for nowthe wife and I are going to have a happy rest. If I can figure out how, I would like to send pictures of the boat and engine.
Thanks to you guys for your help. Dave R.
 
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Dave-R

Chief Petty Officer
Joined
Mar 18, 2008
Messages
441
Re: Water on the Starboard side 7.4 mpi.

Walt you asked to post how this all turned out. We took the boat to the lake to make sure everything was ok. We spent 20minutes at idle and low speeds, checking oil pressure and listening for anything. Then we wanted to see what this boat would do.Wow. I have never had a big block or a duoprop setup. It jumps out of the water with no bow rise. At 55 she was at 4800 rpm and that was enough for both of us. We have a 21' 2001 Rinker with a 350 Mag Mercruiser that until now I thought was a hot boat. The engine runs and idles so quiet that you would never suspect it ever was seized. The trouble is now my kids found out about it and they want it cheap. Dave R
 
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