1996 Johnson 130 hp V4 looper - No power

[rex979]

Just purchased a used boat - 1997 Glaston SE170 with a 1996 Johnson 130. Got it from the original owner, tried it in the driveway with muffs on- ran great. He said no issues with it and cosmetically it was is excellent shape.Get it home, do a compression test- 155-155-150-155. Great. Fill it with a fresh tank of premium fuel and Take it to the lake, starts fine, warm it up, nice even idle, pull away, take it up to 2000 rpm. Everything is good. Push the throttle forward and it won't rev past 2500 rpm ?? Put it in neutral and it will rev to 6000 rpm no problem. Put in gear and it will only rev to 2500 rpm. Return to the dock and put in new spark plugs, same thing. Have the wife drive the boat and I squeeze the fuel bulb, no change. I can see the fuel flowing in the filter with the cowling off, seems fine. When we come back to the dock it doesn't want idle and stalls. I pull the plugs and they are wet. I'm thinking ignition timing issue ? power pack ??
Any thoughts or similar experiences would be appreciated.
Cheers

 

[jimmbo]

You've already done the compression test, so now Check the spark. Does it Jump a 7/16" gap? If spark is good, then focus on the Fuel system.and Throttle Linkage

 

[oldboat1]

To measure spark (test strength of ignition system):



If a permanent tank, draw some fuel from the bottom and check for contaminants. (Use a glass jar, and let it settle out -- water will settle at the bottom.)

Also consider hull condition. Water logged foam under the floor, for example -- amazing amount of weight.

 

[rex979]

Conducted a power pack test/ ignition timing test. Grounded the spark plugs, disconnected the throttle cable, got good blue spark at all plugs when cranking on starter( will do a 7/16" spark jump test later ) The timing light showed 12 degrees BTDC and when I manually advanced the stator plate to max the light showed 24 degrees BTDC. The plastic air snorkel on the carbs has a sticker that reads 18 degrees BTDC. I've ordered a manual but won't get it until next week. so I don't know what the correct timing spec is. However I have read elsewhere that this test I conducted will show 4 degrees less than what it will actually be when running ?
I have checked the fuel as per oldboat1 and it's seems fine and as well, the hull is not water logged.
After running, the hub of the prop just oozes with black soot, so it appears to be running very rich. Would a stuck or bad inlet needle and seat or stuck float be the problem ?
The throttle linkage does not appear to be tampered with as it still has the factory orange paint on the lock nuts undisturbed, so I don't think there is an issue here. The manual should clear that up when I receive it.
Any thoughts ??

 

[boobie]

Do a cylinder drop test on it .

 

[rex979]

Do a cylinder drop test on it .

Sorry, not familiar with that term. Do you mean to short out the ignition 1 cylinder at a time ?

 

[racerone]

Are you sure compression is that high on this motor ?----But also look at the flywheel key , a sheared key will throw out the timing.----And no you can not find a sheared key with a timing light.----Crankcase compression is another thing to investigate too.

 

[rex979]

FYI- UPDATE
Bought a shop manual and checked the power pack. Discovered the problem was the temperature sensor on the port side cylinder head. There is is a 2 wire sensor that measures an overheat condition as well as a WARM UP temp. The warm up sensor ( 99 degrees F ) limits rpm to 2500 until that threshold is reached. It is obviously malfunctioning, but the overheat ( 208 degrees F ) tested fine. So I simply disconnected the white wire with the black trace and it now runs like a Champ !
Thanks to all who chimed in with some opinions.
Cheers !