Seafoam in old engine

[mattLA]

Hello. I have a 1980 85hp V4 Evinrude that is running terrible (loud, choppy idle). I look in a cylinder with flashlight and all I see is black crud on the piston. I was considering putting some straight seafoam directly in the cylinder at full tilt, letting it sit for 30 min or so, then run a concentrated seafoam+gas+oil for a bit.

Any experience with this? Thanks..

 

[SparkieBoat]

Re: Seafoam in old engine

run engine to operating temperature,remove plugs and spray sea foam or I use "Deep Creep" in a spray can which is made by the makers of sea foam. replace plugs let sit 30 mins then crank and run 1 can of sea foam with 1 gallon of premix fuel, and expect lots of smoke. run most of the gallon out then empty into your regular tank. may have to repeat a few times for a real dirty engine.

 

[14ftgrumman]

Re: Seafoam in old engine

Sparkie- you da man. SeaFoam is the greatest thing since canned beer.

Yes, bring engine up to temp and have at it with the SeaFoam.

It will smoke so bad that you will think that you broke something, but that's normal.