Black Tar ?

[firstimer]

I have a 1975 70 evinrude that has sat for a while. The engine would only run when choke was on. You great helpers told me to rebuild carbs and i did; now engine runs when choke is of. We got the motor running and ideling good but it runs very smokey and there is a bunch of black tar looking substance coming from the exhuast (propeller). There was so much exhaust smoke that the fire truck came by for a visit I am running out of water with ear muffs hooked up to hose. Thanks for all of the gtreat help.<br /><br />Brad

 

[R.Johnson]

Re: Black Tar ?

The black tar is unburned fuel, and oil mixing with carbon formed in the exhaust housing. This will clear up when the engine is in proper tune.

 

[daveswaves]

Re: Black Tar ?

More info needed to help out, Did the motor seem to be running Hot? Did you change the impeller? Have you ever run it without the muffs? Is it tar in color or consistency? How much oil did you put in how much gas? As R. Johnson says its probably just fuel and carbon and the engine needs to be tuned up on the boat, under load.

 

[umblecumbuz]

Re: Black Tar ?

Reckon if you get it on the water and thrash it for a while, you'll find that when you flush it through on muffs afterwards, the tar will have gone.