OMC 115 Turbojet/Seaswirl Squirt

[ezeke]

Re: OMC 115 Turbojet/Seaswirl Squirt

Check the compression to see what conditions are before and after. You can use the Sierra Head gaskets - they work fine: 18-2956.

http://www.iboats.com/Sierra_18_295...2838190--**********.336336437--view_id.173745

Be sure to get the right adapter gasket, the one listed in the parts catalog. A regular crossflow adapter gasket will not work.

 

[parrotsummer]

Re: OMC 115 Turbojet/Seaswirl Squirt

I'm thankful beyond words. You just saved me my little boat full of money! I just ordered the gaskets. I guess they will get here in about a week. That sould give me time to move the engine for the compression check, pull the heads, unclog everything and get the adapter plate welded.
Am I looking wrong or is the ehaust manifold and adapter plate one piece or do I just not know what I'm looking at? I noticed two petcocks which seems odd to me. One on the adapter plate and one on the muffler. Also a hose which was zip tied to somewhere must have disconnected but I can't move the engine around well enough to figure out where. The end that is still connected is on the port side of the exhaust manifold portion of the bottom of the adapter plate. I imagine I will see where it goes when I sit the engine back upright.

 

[parrotsummer]

Re: OMC 115 Turbojet/Seaswirl Squirt

I just learned something. The adapter and adapter plate are two different things. Adapter being the engine block to adapter plate and adapter plate being the adapter to mounting bolts on the jet pump assembly. I'm not sure how this will affect me yet but I have only ordered new head gaskets so far so I haven't spent unnecessary money at least. I'm trying to get the adapter plate off but no luck yet. I went so far as to mark each mount bolt since they are different lengths. My manual shows more of them than are on my engine. I have only ten. I also removed the fuel/oil pump cover (coffee can looking thing)as it was mounted to the adapter plate. Now I just need to get the adapter plate to separate from the adapter itself. Is a dead blow hammer a safe way or are there jacking bolts to do this?

 

[parrotsummer]

Re: OMC 115 Turbojet/Seaswirl Squirt

WOOHOO!!!!! 2 knocks with the dead blow and it came apart! About 1 1/2 cups of sand came with it (no exageration) but it is apart. Makes moving the engine around much easier too. The exhaust paths are no doubt clogged by since I'm working in 94 degree heat I didn't stay out there long enough to start checking cooling paths. I'll take the adapter plate to my friend tomorrow and ask if he can put a fitting on it to pressurize it while he has it to weld repair it.
I'm guessing from the amount of sand I'm going to find some problems in the cylinder heads. I am now regretting not checking the compression. I really don't think I am capable of going that far inside the engine. This means I'll clean it out the best I can. Put it all back together and drive it until it stops making power then sell a used jet boat with a bad engine for whatever I can get for it.
I am just very happy and thankful to you for getting this far. It's not over yet though. Maybe I'll be pleasantly surprised.

 

[ezeke]

Re: OMC 115 Turbojet/Seaswirl Squirt

The engine first sits on a plate and the plate sits on the adapter that you need to have welded. The special gasket is the one between these two pieces part #340380. It was only used on TurboJets.

The gasket above the plate is common crossflow part #321727 or 342513. It crosses to the Sierra Gasket 18-2864.

 

[ezeke]

Re: OMC 115 Turbojet/Seaswirl Squirt

Guess we need to see why the sand filter did not work.

On the one's that I've worked on if the o-ring and filter were good, sand would not have gotten past it.

 

[parrotsummer]

Re: OMC 115 Turbojet/Seaswirl Squirt

Thanks. That is exactly the one I thought.
I saw something that reminded me of a past repair. The exhaust manifold part of the adapter plate developed a crack and a friend and I pulled the engine out, left it hanging on the hoist, stop drilled the crack on both ends, V'd the crack out with a Dremel tool, JB Welded it and put the engine back in. It looks great still. I wish I still lived near this friend to enlist his help.
I pulled the 90 degree fitting from the top aft of the muffler and although I got no gunk out of it on a thin bladed screwdriver I am now able to blow through it clearly. I'm not sure what it broke loose but something must have gone back into the muffler. I wish there was a way to flush that muffler really well. I've heard to use muriatic acid at a household strength but I don't know which is in and how much should be coming out of which lines or fittings. If I ever get my hands clean (I ran out of latex gloves) I think I'm gonna be happy over today's progress.
Thanks as always to you kind Admiral.
I haven't heard from Skeetr lately. I hope he is busy out enjoying his own boat.

 

[ezeke]

Re: OMC 115 Turbojet/Seaswirl Squirt

There are three fittings on the muffler. The front top one was connected to the tops of the two cylinder heads. The front bottom one was connected to the adapter on the starboard side. The rear one went out the transom plate. They are basically cooling for the muffler. The outlet at the transom is a poorly located tell-tale since you can't see it from inside the boat.

 

[parrotsummer]

Re: OMC 115 Turbojet/Seaswirl Squirt

I just pulled the thermostats. I guess that is what is in those globs of sand in the housing for the thermostats. LOTS of sand but I am able to blow through the top cylinder head tubes (isn't that actually backwards of the water flow direction?) freely. I will order that rebuild kit you suggested tonight. I'm getting the adapter plate welded tomorrow and I will take off the heads and start cleaning things while waiting on parts to arrive. Hopefully by this time next weekend I will have it all back together and in the boat. In no small part thanks to you and Skeetr.

 

[ezeke]

Re: OMC 115 Turbojet/Seaswirl Squirt

The water goes through the engine first then to the thermostats; the thermostats then control much of the water flow. The two outlets at the top of the cylinder heads also have water flowing away from the engine.

Since the water is always pumping whenever the engine is running, much of the water is bypassing the engine unless the thermostats are open, so a lot of sand at other points does not mean that it necessarily is in the engine.

If you do find sand in the engine it will likely be in the cooling passages where it can be flushed out.

 

[parrotsummer]

Re: OMC 115 Turbojet/Seaswirl Squirt

Good evening. I'm going to try to adapt either the garden hose or my home medical oxygen hose to try to best flush the block's cooling passages. After doing that as best as I can I will pull the heads and check for debris, damage and condition/position of the deflectors. I would actually pass on pulling the heads if I hadn't already ordered the gaskets.
Is there any reason the adapter plate/muffler assembly cannot soak overnight in parts cleaning solution? Since the muffler has not even been loosened from the adapter plate I don't think it can affect the gasket.
As for the sand filter I'm confident that the hard grounding a few years ago is what overwhelmed it. I'm just happy my mistake at that time didn't cause alot more damage. I feel REALLY lucky with that.

 

[parrotsummer]

Re: OMC 115 Turbojet/Seaswirl Squirt

Oops... I forgot to ask. If there is no crack in the block (like from a cooling passage into the cylinder) is there any other way besides through the fuel system that sand could actually get into the cylinders? I know the compression check will reveal the possiblity of cracks or worn rings or warped or loose (untorqued)head or incorrectly seated gasket or a number of other things but does that also cover exhaust problems?

 

[ezeke]

Re: OMC 115 Turbojet/Seaswirl Squirt

If you put enough water pressure on the incoming water line, as with a hose fitting on a public water supply, you can literally push water back through the exhaust ports and into the engine, along with whatever is in the water.

 

[SKEETR]

Re: OMC 115 Turbojet/Seaswirl Squirt

I have always heard it is best to flush the engine with it running to prevent water from getting into the cylinders.
Do the thermostats still work?

 

[ezeke]

Re: OMC 115 Turbojet/Seaswirl Squirt

I have always heard it is best to flush the engine with it running to prevent water from getting into the cylinders.
Do the thermostats still work?

That's true, but the TurboJet has a 20 PSI bypass on the jet pump for normal operation and most city water systems are at around 60 PSI. Full 60 PSI pressure/stream is too high whether the engine is running or not. When you use the flusher, you just need enough pressure to keep the flow stream up.

 

[parrotsummer]

Re: OMC 115 Turbojet/Seaswirl Squirt

Good morning folks. Nice to see ya back Skeetr. I'm talking about flushing the paths with the engine as it is at the moment. With the adapter plate/muffler and it's manifold off. Just to push whatever junk is in there through before I pull the heads and it falls into the cylinders. I always turned water on after starting the engine to flush it because I've heard the same thing. The adapter plate with muffler still attached is at the machine shop now for welding and cleaning/flushing. I'm told I'll get it back Friday. I see my head gaskets shipped this morning but I still need to order the thermostats/rebuild kit and the adapter plate gasket. Plus I have ALOT of cleaning to do.

 

[parrotsummer]

Re: OMC 115 Turbojet/Seaswirl Squirt

I've come to a block. I was just trying to order the thermostats and noticed it said for up until 1995 and mine is a 97 so I called iboats parts. They referred me to Sierra who says they can't locate any parts for this. I explained that it is a normal OMC 115 power head and that I odered 2 headgaskets from them so they must have something about the motor. He referred me to any local OMC dealer. Now I can't replace the thermostats. I'm thinking now of just not putting them back since the ones in there are definitely shot. Do I just leave ALL of what was in there out and get gasket material to make new gaskets or seal it up with rtv and be done with it? Will the same high temp rtv be okay to seal the new adaptor plate gasket? What about for the head gaskets? I know I need anti seize compound for the bolts. I spent all morning after dropping off the adapter plate cleaning old gasket and general grime off. I'm going to mount the engine on a workbench next to remove the heads but still need help to move the engine. Even with the adapter plate and muffler off I can only lit it a few inches off the ground.

 

[ezeke]

Re: OMC 115 Turbojet/Seaswirl Squirt

The thermostat kit #18-3673 contains two of the correct aftermarket thermostats.

The OEM individual thermostats that are correct are #434841. These cross to the Sierra part 18-3553.
If you use Teleflex Sierra's cross reference with the number you will have a valid Sierra Part (and you won't have to deal with the LCD on the other end). http://ww2.sierramarine.com/sierra/catalog/interoem.asp?oesearch=5005440

 

[parrotsummer]

Re: OMC 115 Turbojet/Seaswirl Squirt

Thanks. After talking to several people at several places I feel confident that is correct and ordered them less than ten minutes ago.I sure do hope my memory is good enough for me to get this engine back together completely and correctly. Is the high temp RTV okay for all of the gaskets?
Thanks for the help I'll spend the rest of my life trying to repay. I even praised you two to the guy I spoke with at Sierra.

 

[ezeke]

Re: OMC 115 Turbojet/Seaswirl Squirt

I use 3M 847 on the engine and none on the head gaskets.