96 115hp crossflow Intermittent won't rev up... But sometimes it does. Help

J

jgouras

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Sep 30, 2009
Messages
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So it's a crossflow but a turbojet. Starts idles and runs great. Had it out today ran for 15-20 min great power no issues, then while at full throttle the rpm's just drop. Dont have a tach but speed dropped from 48 to 18. Will not power up, heading to the dock and I get occasional blips of full power then it drops off again. This has happened before but I thought it was debris in the impeller but it's not. I have tried searching but can not find what I need.
 
86 century

86 century

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986
Re: 96 115hp crossflow Intermittent won't rev up... But sometimes it does. Help

Start with the fuel system sounds like you have some kind of a restriction in fuel delivery.
If you take it out again try hitting the choke/inricher to see if that helps.

Would be a good idea to look over the ignition wile you are at it.
 
E

emdsapmgr

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Dec 9, 2005
Messages
11,551
Re: 96 115hp crossflow Intermittent won't rev up... But sometimes it does. Help

Possible that a sudden drop in power is a problem with the ignition system. Likely the engine is not running on all 4 cylinders. You can check for spark with a simple test. Run the engine on the garden hose. Make sure it is fully warmed up. Pull one of the spark plug wires off one plug with a set of insulated pliers. The rpm's should drop dramatically. Replace the plugwire and do the next cyl. If one cyl does not have an rpm drop-likely it is not sparking. Or you can use an inductive timing light to check for spark. The flashes from the gun will show misfires, no fires, weak firing, etc.
 
J

jgouras

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Sep 30, 2009
Messages
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Re: 96 115hp crossflow Intermittent won't rev up... But sometimes it does. Help

So I tested the coils per the manual, they were all in spec. I did the run test and all four cylinders responded the same, dropping of the rpms and a rougher run. Any other ideas?
 
86 century

86 century

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Messages
986
Re: 96 115hp crossflow Intermittent won't rev up... But sometimes it does. Help

You will haft to put it in the water to test fuel by hitting the choke.
 
J

jgouras

Cadet
Joined
Sep 30, 2009
Messages
9
Re: 96 115hp crossflow Intermittent won't rev up... But sometimes it does. Help

Problem solved, out of frustration I bought parts and slowly replaced until it worked. It was the power pack. Now it runs like a champ.
 
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