Foamy oil from exhaust

[hornytoad]

Hello all i have a 1979 35 hp johnson model 35el79a. I've had it for 5 years and it has been a very reliable motor. Recently it started caughing and idling very rough. I ran some seafoam through it and it helped but then it got worst to where it would die after running at wot. I waited about 30min and it started right up but would only go to half speed at full throttle. I decided to rebuild carb and now when i run it on muffs i noticed this foamy oil coming from exhaust at prop. I thought it was from lower unit so i removed oil and it was normal but when i removed lower unit i found this stuff. Any idea as to what would cause this or how to fix it?

 

[hornytoad]

Well tried uploading pics but file size was exceeded???

 

[Chris1956]

Well, it could be a number of things. I would first check for spark on all cylinders. Next I would check the fuel pump for a diaphragm leak If that is good, check the carb for proper float height.

 

[jimmbo]

Perhaps the Seafoam is still coming out

 

[Scott Danforth]

were you simply idling along..... then its unburned fuel and oil, probably mixed with seafoam.

and to post pics, you need to resize them to about 400k

 

[racerone]

Find out why it has no power.-----Do a proper spark test as stated already and also a compression test.

 

[F_R]

No power==more than likely it is running on one cylinder. The fuel is passing through the non-firing cylinder and going out the exhaust, where it emulsifies with water and turns to glop.

Could be as simple as a fouled spark plug, from dumping that sea foam in it.

 

[hornytoad]

Thanks for the replys! I will check for spark when i get off work. As far as fuel pump it is brand new but will look for leaks. I dont have a pressure guage to check compression. I will get some new plugs on my way home. I really wish i could post a pic but im not tech savvy. The foamy stuff is thick and nasty and just dripps out of prop while idleing on muffs only a pic would do it justice. Again thanks for all the replys

 

[hornytoad]

One more thing. While it was idleing lastnight i pulled the top plug wire and it stumbled and died. I restarted it and then pulled bottom plug it stumbled also not near as bad as top one and it stayed running. Not sure if that means anything?

 

[oldrem]

Most auto parts stores have compression testers they will loan out. Pay for it when you pick it up and get your money back when you return it in good condition.

 

[hornytoad]

Thanks there is an autozone nearby

 

[jbuote]

Not a pro here at all, but based on what you described by pulling the plug wires.. .(cylinder drop test)

Top wire pulled, it stumbled and died...
Bottom pulled, it stumbled a little, but kept running...

If I'm not mistaken (and I could be), that (to me) would indicate the top cylinder seems to be running fine, but the bottom either isn't firing at all, or is intermittent at best..

Sounds like an ignition issue on the bottom cylinder so focus there, but testing the whole thing would be a good idea just to make sure it's all top notch and working properly... (Adjustable spark gap tester, checking wires, boots, looking for corrosion, coils, etc....... )

Could just be fouled plug as indicated already...

Hope it helps a little... lol

 

[hornytoad]

Ok heres what i know so far. I performed a spark test with tester set at 20 and had a big blue spark on both wires. I performed a compression test and had 115 psi on one cylinder and 120 psi on the other. I cant remember which was which coz it started raining on me and was in a rush to unhook everything. I replaced the spark plugs and started the motor. Right away i noticed a difference in the idle it was a bit smoother but not smooooth also the foamy oil was still coming out but nowhere as bad as before. I had left the motor tilted up as i was getting parts and noticed when i got back there was some fuel pooled under the carb. I guess next thing ill do is check the float level. Any other things i should check?
thanks to all who replied