94 115 crossflow firing on all 4?

SKEETR

Chief Petty Officer
Joined
May 3, 2008
Messages
430
The v4 sits inboard on a jet drive. I get good spark at idle on all 4 but have yet to achieve a good high rpm since rebuild. During break in I noticed a grayish film covering the jet which I assumed was just the excess oil I was adding to the gas. The exhaust dumps at the bottom of the jet. I cleaned it up after break in and am mixing 50:1 now. After my last trip I noticed the same gray film on only one side of the jet so I figure perhaps my rpm issue is a bad starboard coil or power pack not firing at higher rpm's. Am I on the right track? I am all thumbs when it comes to testing components I'd rather just buy new stuff than loose any more hair. Didn't notice a miss or stumble at idle or wot, can a v4 run relatively smoothly with only 3 firing?
 

woody66912

Senior Chief Petty Officer
Joined
Jul 12, 2008
Messages
690
Re: 115 omc turbojet firing on all 4?

Re: 115 omc turbojet firing on all 4?

you said you have not got high rpm what is the rpm? and not since a rebuild.did you rebuild or a shop rebuild.you have a what is call a looper.just a though but i have seen it before where the pistons were installed backwards.the arrows on the pistons should point towards exhaust.also make sure your coil primary wires are hooked up right. or/blu to top coil or/gr to bottom .grey oily exhaust usually is a sine of timing issues.also a flywheel key that is partly sheard can also do this.
 

SKEETR

Chief Petty Officer
Joined
May 3, 2008
Messages
430
Re: 115 omc turbojet firing on all 4?

Re: 115 omc turbojet firing on all 4?

I did the rebuild myself. I am sure I put each piston in correctly. It is a crossflow, sorry for not stating enough info. I get about 4800 rpm at wot. I am sure the carbs are dialed and sync'd. Timing 28 btc. Not sure how a hardened key can be partially sheared?
 

SKEETR

Chief Petty Officer
Joined
May 3, 2008
Messages
430
Re: 94 115 crossflow firing on all 4?

Just realized that the exhaust doesnt actually split to where it would indicate a specific cylinder from either side of the exhaust at the jet. Duh, must just be an effect of the water turbulence.
 
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