1996 evinrude 48 wont idle slimy exhaust

[Vallario]

I have a 96 evinrude 48. i bought this boat not too long ago. it had been sitting for a while so i rebuilt the carbs. first time out ran great idled fine. second time out it ran great for the first 30 min then had trouble idling. wot is great. Got home to diagnose problem. Noticed a little oily gunk comin out of exhaust. Didnt think anything of it. so i got it to idle again but had to adjust idle screws inn more but idled poorly. i had a buddy look at it and he thinks water is getting in my cylinder. chenged head gasket. went out again idled for a few more minutes then ran it. this time even more sludge came out. if there is water getting in. where else could it come from. I am gonna change the crank seal at the bottom and exhaust cover gasket. am i on the right track. ??

 

[Will Bark]

When you pull the plugs is there any water on them? The slimey sludge you are seeing could just be unburned oil/gas mixture and would be normal. Don't go throwing parts and money at it until some of the gurus on this site have a chance to chime in with their thoughts. Give them the model # off the transom bracket tag so they know what engine you are talking about. This could be something simple to rectify. Good luck

 

[Vallario]

I think the kid that looked at the boat was going on the exhaust. when i pulled the plugs they didnt look steam cleaned or watery. bottom cylinder looked like the plug was more oily than top but not crazy bad. Its confusing cause it happened out of nowhere. he thinks water is getting behind the piston not in front. Compression is good. carbs rebuilt and ran great first day. its like i blezw a gasket or seal and its getting worse progressively. i dont know anything about diagnosing electrical systems. there is no water in fuel. i changed the water separator and bulb thinking it was a fuel issue and nothing. the tank is venting. fuel filter also. So the carb screws have to keep getting readjusted to idle and the exhaust gunk is getting worse.

 

[Will Bark]

If water is getting in the cylinders you would see it on the plugs no matter what. The gurus will need to chime in on this one but one other area is that the thermostat may be wide open and the engine is running too cool; you need to check the temp with an infared temp gun which you can get for cheap at Harbor Freight. Good luck