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OMC 115 TurboJet starting issues

billdoucet

New member
Hello from the wilds of Nova Scotia. We only have about 15 minutes of summer so I'm in a hurry to get my most recent purchase on the water. I'm hoping someone can give me a nugget of wisdom that will make the difference.

Bought this Whaler Rage 15 with an OMC 115 TurboJet. I know about the issues that folks have with them but the price was too good to pass up. The boat was sold after the owner passed away. His son told me that the boat ran well two or three years ago but has been sitting since. It also came with 3 jet drives, a complete extra engine and several boxes of extra parts. His dad was a bit of a pack-rat and was kind of obsessed with the boat.
So... the engine won't start

1. The engine turns over well. Starter appears to be strong.
2. There is spark to all 4 cylinders. I have a spark tester and everything looks great.
3. I've just cleaned the carbs. there was some dirty gas in the bowls but not a lot of particles.
4. I've drained the old gas from the tank and replaced with a 50:1 mixture
5. The valve in the primer bulb was bad so I've replaced the bulb .
6. Each cylinder has good compression although the upper right side only has 95 psi while the other three have between 105 and 110
7. Gas does NOT appear to be moving through the system. The primer bulb works well and pulls gas until I reconnect it to the line going to the fuel / VRO pump. It's obvious, at that point, that the bulb is not moving fuel

The engine turns over ...and over and over ... but will not start.

Should fuel pass through the pump when the key is off? Any advice as I try and trace what I think is a fuel blockage?

I would appreciate any advice that anyone might give me. I'm a great youtube mechanic but really an elementary teacher by trade...

Bill

OMC 115 TurboJetOMC 115 TurboJetOMC 115 TurboJet
 
Key on or off has nothing to do with fuel going through the pump.-----Is the electric primer valve working?-----Are you pushing the key in while cranking it over ?
 
Some will argue.-----Your compression numbers say that motor needs work.----Perhaps test with another gauge.----Perhaps check the flywheel key.
 
What should the numbers be? Are they low in general or is it the difference between the low one and the other three. (everything I do and read I have to google or youtube :) )

I do have another motor and lots of parts ...maybe there's a reason why ...
 
So - at this point I've made sure there is good fuel flow, compression, and spark The only thing I can think of is timing. I'll pull the flywheel tomorrow and check the key - thanks to racerone for the suggestion. It sent me down a research hole but I learned a whole bunch!

 
You were bang on with the flywheel key suggestion. The flywheel was spun halfway around - no way that was going to start. I've replaced it and will try starting it in the morning. I'll let you know how I make out! Thanks so much for your help!
These are the pieces...
keys.jpg
 
Just in case anyone is reading this ... I got a new compression tester and the compression is actually higher than I originally thought. it's now 110. 120, 120, 120
This is what I've done so far - many thinks to racerone for pointing me in a few directions that bore fruit but ultimately have not gotten th eboat going. MAybe it's time to take it to a shop...

1. I replaced the Woodruff Key with the correct replacement. The original was sheered off. Re-torqued the flywheel nut to 105 lbs
2. New plugs
3. Cleaned the carbs, replaced the old gas (not much there to begin with)
4. Checked compression today - 120 on 3 and 110 on the top starboard side.
5. Checked all plugs and am getting good spark on all 4
6. Squirted 50:1 mixed fuel in each cylinder and tried to start.
7. Starter is strong with a new battery.

Nothing... anyone have any ideas?
 
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