1979 Johnson 150 Exhaust issue

[Larson70]

I have a 1979 Johnson 150 that I got running for the first time in 12 months. I did the proper starting methods when you have had a motor sitting for a long time. To my surprise it started right up and runs like a top. The only problem I am experiencing is a small poof of smoke randomly (once every minute or so) out of the area around the 2 fuels pumps and starter. I assume its the plate behind the carbs has a bad gasket. It doesn't look like a major problem but does anyone know what gasket that is or have any tips, advice, or know what it could be? Thanks.

 

[emdsapmgr]

Re: 1979 Johnson 150 Exhaust issue

The only thing back in that area are the two pulse lines for the two fuel pumps. Those lines are plumbed directly into two cylinders of the block. If the pulse lines were old, perhaps cracked, you might get some blowback from the area of the hose crack. Esp if the engine were cold (not warmed up) and the engine was occasionally sneezing prior to warmup.

 

[Larson70]

Re: 1979 Johnson 150 Exhaust issue

This sounds 100% correct. I appreciate the help.