chrysler 115 miss or snezze(help)

[stoney747]

Hi. I have an CHRYSLER 115,1979 with MAG IV ignition and distributor. It starts up quick, but at idle and trying to increase power,in and out of the water, it would cough or miss out of the exhaust snout intermittley. The carbs where cleaned and new kit installed, new fuel pump and lines. IT also has the gapless spark plugs. The compression is within limits (140 139 139 141) What did I forgot to do or check. PLEAS HELP!!

 

[MikDee]

Re: chrysler 115 miss or snezze(help)

It sounds like one of your exhaust reed valves is hung open, or sticking if it backfires (coughs ) out the exhaust occasionally.

 

[Frank Acampora]

Re: chrysler 115 miss or snezze(help)

If the carbs were rebuilt, check to see that they are not running too lean. This can be disasterous. Start at 1 1/4 turn out from lightly seated and adjust the idle 1/8 of a turn at a time. Do not go leaner than 3/4 turn out from a lightly seated position. After you adjust them, performance check by applying full throttle from a dead stop. If the engine sags down then recovers and accelerates, it is too lean. Open both needles 1/8 turn and repeat. If it stumbles and stutters then clears itself and accelerates, it is too rich. Close needles 1/8 turn at a time. However---DO NOT GO LEANER THAN 3/4 TURN OUT-- Running too lean will melt pistons.

Idle should be set at about 700 RPM in forward gear in the water.

 

[MikDee]

Re: chrysler 115 miss or snezze(help)

I've found that if an outboard is too lean, one symptom is, it will usually backfire or (cough) out the carbs.

 

[stoney747]

Re: chrysler 115 miss or snezze(help)

Thanks fellow CHRYSLER owners. So you are saying that the best way to adjust the carbs is in the water?

 

[Frank Acampora]

Re: chrysler 115 miss or snezze(help)

you can adjust the carbs in the driveway with the engine on cooling muffs, but adjusting the idle requires the engine to be in the water and final adjustment of carbs also requires being in the water.
Marinas have test wheels which load the engine and don't throw water, so they can use a test tank. Most of us don't have test wheels so we must test with the boat on the water.