restoring oil injection? Why was it bypassed?

[JoshMurrah]

ok, so I bought this boat, it's a 900 boat+trailer combo, so y'all know what to expect......

The good news is that it's "all there" and these look like original engines to me based on paint colors and the engine tags still on the blocks.

There's a lot of weirdness going on with fuel and electrical, but the main one I'm worried about, asking about, is that it looks like to me like the oil injection is bypassed - there's a vice grips on the lower oil line (not joking it's in the pic) - why would somebody do this? Can I just replace the lines/oil/gas and fill er up and go?

if you're bored and still reading, check out the cut fuel lines, the loose sender, and the friggin catch can off one of the carbs, I don't even know what that's about... and there's a loose throttle style cable, but it looks like it goes to the other carb or to the oil pump area, clueless about that one. What a project!

 

[burtshaver2021]

Follow the line back to the oil tank. I’m thinking maybe that’s the oil line to the rotary valve and he crimped it because the inner crank seals were leaking, if it goes to the bottom of the oil tank and beneath the rotary valve then that’s what it is. Could also be that he was working in something and just crimped it to keep oil from going everywhere. Is there an oil filter on that line? If yes, then it’s the oil line to the oil pump

 

[mikidymac]

Also all those fuel filters are a disaster waiting to happen too.

 

[JoshMurrah]

The more I dig in, the more I didn’t like things - fuel lines in disarray and original separators gone, half melted in-line gas filters, one is bypassed for oil injection (oil pump cable is disconnected, injection lines to carb blocked) but the other one isn’t - one engine, at least, is vintage original with black oil injection lines with white paint - I’m making the call to stop and pull everything, clean and re-plumb everything and do crank-up rebuilds and put injection back in. From what I’ve seen the rotary valve really has to have injection so I’m not sure bypass is even ok on these - and the oil tank didn’t have anything in it.

I’m gonna leave a fun pic - I’m not sure what is actually melted here, any ideas? - but the battery still had good juice in it haha. It’s probably related to one of the starters being not installed.

 

[burtshaver2021]

I don’t know how experienced you are at restoring these but if you don’t have a lot of experience I’m thinking it might not be a bad idea to consider something not so molested and ragged as this one. Just trying to keep you from getting in to far before you realize that it may be a lost cause. I typically don’t do anything cosmetically until I’ve got the machine running or I will at least inspect t everything well so that I know what I’m getting into before I start. Are you able to crank these engines over to do a compression test? Have you been able to verify that the MPEM is good? The previous owner seems like he may have been a hack. If you have to buy electronics, rebuild fuel lines, carburetor s, fuel system, pistons rings, bore, crankshaft, counter balance shaft, possible jet pump rebuild, you could be in for a pile of money, anyways all I’m saying is try and figure out what it needs before sinking anything into it. Just my opinion. Good luck

 

[JoshMurrah]

I don’t know how experienced you are at restoring these but if you don’t have a lot of experience I’m thinking it might not be a bad idea to consider something not so molested and ragged as this one. Just trying to keep you from getting in to far before you realize that it may be a lost cause. I typically don’t do anything cosmetically until I’ve got the machine running or I will at least inspect t everything well so that I know what I’m getting into before I start. Are you able to crank these engines over to do a compression test? Have you been able to verify that the MPEM is good? The previous owner seems like he may have been a hack. If you have to buy electronics, rebuild fuel lines, carburetor s, fuel system, pistons rings, bore, crankshaft, counter balance shaft, possible jet pump rebuild, you could be in for a pile of money, anyways all I’m saying is try and figure out what it needs before sinking anything into it. Just my opinion. Good luck

I’m in 100% agreement that I’m in for a lot - I bought it as a long term project and don’t expect to come out financially on top - I’m figuring on rebuilding everything too to bottom, about 3k plus another 1k for interior - it doesn’t add up financially but it’s just a fun project and I’ll end up with something much fresher in the end.

The question about the MPEN is a good one and I really don’t know how to test it without rengines I’d trust to run, and I’m not there yet. It there really any to test it without starting engines? I did connect electrical tonight and all of the usual secondary stuff like dash lights and evac fan worked. Horn and buzzer didn’t work not surprised.

 

[burtshaver2021]

I’m in 100% agreement that I’m in for a lot - I bought it as a long term project and don’t expect to come out financially on top - I’m figuring on rebuilding everything too to bottom, about 3k plus another 1k for interior - it doesn’t add up financially but it’s just a fun project and I’ll end up with something much fresher in the end.

The question about the MPEN is a good one and I really don’t know how to test it without rengines I’d trust to run, and I’m not there yet. It there really any to test it without starting engines? I did connect electrical tonight and all of the usual secondary stuff like dash lights and evac fan worked. Horn and buzzer didn’t work not surprised.

If the buzzer was working, if you get the 2 beeps then the mpem recognizes the DESS Key, when I have been purchasing, if the machine will send power to the starter that’s always been good enough for me. There could be more to it, and I may have just been lucky though.

 

[JoshMurrah]

If the buzzer was working, if you get the 2 beeps then the mpem recognizes the DESS Key, when I have been purchasing, if the machine will send power to the starter that’s always been good enough for me. There could be more to it, and I may have just been lucky though.

Oh ok well one of the engines will turn over - so that’s good - I do need to replace the buzzer to make sure tho - I gotta see where the battery cutoff is or add one, before I leave the battery permanently connected tho. I just got the service manual printed last night so I’m about to dig in.

 

[JoshMurrah]

coming back to this with an update since it's so weird -

1) The melty part above the battery - is one side of the oil tank (!!) - so I need a new oil tank long term. I'm guessing there was a small fire (battery issue?) there at some point - I'm also missing the compartment breather with the foam in it, on that side.
2) The oil line that's pinched, is the starboard engine's oil pump. The starboard engine doesn't have any injection line changes otherwise (has the original painted-over small injection lines)
3) The port engine, has been bypassed... the oil pump's outputs, and inlets to the rotary valve are cut and capped, and the throttle cable disconnected.
4) All of this together looks like the boat was bypassed and ran that way - I'm not 100% sure if this is great long term, especially with the reservoir empty - I probably at least need to replace the tank and put some token amount of oil into it.
5) so far, both engines look like they're ok to me - they both rotate via the PTO - I have starter issues (the DESS works, and I can click the relays tho) but will compression test them soon once that's resolved.

I'm not sure this bypass is ok for the engines long term? What does the lower input and return do, does it cycle oil through the rotary valve area or crankshaft area? How's that actually pumped since there's no pump inside the engine?

 

[mikidymac]

The oil doesn't circulate in the rotary cavity but it does have an inlet hose and the other is just a vent so pressure doesn't build up or a vacuum.
Yes, you always have to have an oil supply for the rotary cavity.

Most people bypass the oil injection because the "word on the street" is that all oil injection is bad and will fail, destroying your engine. So everyone "knows" you bypass it.

Well not on Seadoo's it is dead reliable with very little required maintenance so it should be kept.

 

[JoshMurrah]

Sounds like I for sure need to get an oil tank then - thanks!

 

[JoshMurrah]

people are nuts on these bypasses - I got a second boat for parts (including the oil tank) - some bozo snipped off one of the lower lines and looped it to the upper return, on the parts boat.

 

[noooby]

I had a similar mess with my 94 Speedster. Wiring had bypasses in it, engine compartment full of water, nothing really worked.

I pulled both engines, all the wiring and fuel and oil lines out of the engine bay. Then pulled the gas tank out (it was a tight fit even with the engines out!) and cleaned all the nasty smelly goop out.

Then I rebuilt the engines, new oil and fuel lines and then started on the electrics. My MPEM was dead and the 94 year is a one-off because it has 5 wire stators. So I did the twin MPEM conversion. Take to Jet Ski MPEM's that run the same engine and stator as you and send one to the left engine and one to the right. I lost all the safety lock outs and I don't get beeps anymore (except overtemp, which I tested to make sure) but at least the boat goes!

Not familiar with the 787 but with the 657X and 717, the manual doesn't say to put sealant around the outside of the crank seals that go in the Rotary Valve housing. If you don't put sealant on, the oil will eventually leak out. Local engine builder told me that trick. I actually added a shut off valve in the Rotary Valve oil feed line for winter storage to reduce load on the seals. Not sure if it helps but it doesn't hurt.