1996 88hp Johnson

[Grebe]

I found a pontoon that was exactly what I wanted with the exception of the Johnson on the back. The motor cranks up and runs good the problem is when you cut it off. Whenever it sits for a few mins it doesn't want to start back and if it does it will bog down when you give it gas and cuts off. I have cleaned carbs, new bulb and fuel line, 4 new coils, new plugs and wires. Any help is greatly appreciated.

[Grebe]

Ttt. Compression is 125, 120, 125, 120

[FishSticker]

Could be fuel pump, ignition, power pack, etc...make sure the plugs are Champion L77JC4...NGK and others will give you fits chasing a problem that is plug related.

Next time it happens, pull the plugs and see if they are wet or dry...wet equals spark/ignition issue, dry would be a fuel delivery problem.

Ran these motors for years...still have a 90 degree 115 on my inshore rig. Very simple motors....plenty of parts and knowledge out there.

[Grebe]

Could be fuel pump, ignition, power pack, etc...make sure the plugs are Champion L77JC4...NGK and others will give you fits chasing a problem that is plug related.

Next time it happens, pull the plugs and see if they are wet or dry...wet equals spark/ignition issue, dry would be a fuel delivery problem.

Ran these motors for years...still have a 90 degree 115 on my inshore rig. Very simple motors....plenty of parts and knowledge out there.

Plugs are the champions. I pulled the plugs yesterday and three are wet, bottom left plug looks brand new.

[FishSticker]

Plugs are the champions. I pulled the plugs yesterday and three are wet, bottom left plug looks brand new.

So we know it should be ignition/spark issue...

Put an inductive timing light on each plugwire. The flashes in the gun will tell you if you have good spark, intermittent, or weak spark or no spark to each plugwire. Ignition problems (weak ignition components) tend to show up once the engine heats up to normal operating temperature. Check the ignition wiring when it is running-look for any wires that may be grounding out to the block, esp the lower ones that are close to the cowling latches.

[FishSticker]

Boat runs well once it starts when hot? Idles fine and doesn't cut out at WOT?

All of mine(5 or 6 over the years) have been persnickety at the "in-between" temps of needing choke or not needing choke....they always seem to like some throttle when starting warm as well.

[Grebe]

The light showed i had good strong spark on each cylinder. It runs smooth and about 5200 rmps at wot. I thought I had the problem fixed yesterday with the new coils. I ran it for probably 20 to 30 mins then pulled it on the bank and cut it off, backed the trailer down and it didn't want to start and when it would finally run as soon as you put it into gear it would just bog down and die out.

[FishSticker]

The light showed i had good strong spark on each cylinder. It runs smooth and about 5200 rmps at wot. I thought I had the problem fixed yesterday with the new coils. I ran it for probably 20 to 30 mins then pulled it on the bank and cut it off, backed the trailer down and it didn't want to start and when it would finally run as soon as you put it into gear it would just bog down and die out.

That being said, Im thinking float valve or possibly primer valve allowing a flooding condition...next time it does it on water, try advancing the timing manually and see if she starts. Timing advance arm is located just under the flywheel....may be time for a carb job. Complete rebuild not just cleaning.

[Grebe]

Thanks for the advice fishsticker. I just talked to a boat mechanic and he said the same exact thing. He thinks that cylinder is getting flooded out.

[FishSticker]

Thanks for the advice fishsticker. I just talked to a boat mechanic and he said the same exact thing. He thinks that cylinder is getting flooded out.

No problem...glad to be able to help if I can. One trick on these motors if they do flood, you can tilt the engine all the way up leave it in that position about five minutes and all the fuel will run out the front....tilt her back down and she will normally pop right off.

[willyworm]

When you had the carbs off did you look at the reed valves? Might have a broke petal. Figured that would be an easy check.

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