Blowing oil....????

[terriphill]

Today we seem to have the electrical worked out, motor sounds great, but it is smoking quite a bit. Husband actually backed it out of the garage and down the driveway. It has good power. Barked the tires coming back up the incline, but it has oil being sucked up through the carb. (header installed with a weber downdraft carburetor) Any ideas? Why is there oil in the carb?

 

[DrEntropy]

There's no straight path from an oil galley to the intake that I know of so it isn't sucking oil thru th' carb unless the crankcase vent is ported to the intake.

How old is the fuel you're running thru it?

 

[terriphill]

I don't want to be stupid, but its ported through the carb breather right now...where are we supposed to port it?

 

[DrEntropy]

Try allowing it to atmosphere and see if the smoke clears.

How OLD is th' fuel?!?

 

[terriphill]

We just put new gas in yesterday (let it run out idling while we fiddled with it) Atmosphere?

 

[DrEntropy]

Don't port it to ANYTHING. Let it blow out into the air.

We're trying to determine if the rings are shot or not seated, mebbe valve guides/seals are at fault.

 

[terriphill]

Thanks, we will give it a try tomorrow and see what we get.

 

[terriphill]

Ok...checked compression today. Good compression in all cylinders. Adjusted valve clearances...all set according to manual specs. Removed the vent hose that we had running to the carb to let it "atmosphere" still smoking like a crop duster and running VERY rough. It runs and has good power, just smokes black smoke. We assume this means a valve job in our future? Also, it should be noted wee never re-attached any of the pollution control canisters, just blocked them off.

 

[tony barnhill]

A dumb question: is the front side cover clogged?

 

[terriphill]

Dumber question: front side cover of what?

 

[tony barnhill]

engine....right up under the carb.

 

[terriphill]

ah..I know right where you are talking about, I'll check. Thanks.

 

[14dna]

Terri;
What color is the smoke?

Dave

 

[terriphill]

black! Like soot.

 

[14dna]

Terri;
That sounds a whole lot like rich mixture.
It takes a lot of oil to get black smoke.
Those weber carbs are famous for being too rich at idle.
Try leaning out the mixture screw and maybe even messing with the choke.
Just a thought, hope this helps.
Dave

 

[PAUL161]

Black smoke is fuel, like too much being dumped into the engine. Blue smoke is oil. I would guess that you have an extremely rich fuel problem. Possibly a stuck float, stuck needle valve or maybe a float that's full of fuel and staying on the bottom of the bowl. Just guessing, mind you, but it sure sounds like a fuel problem to me. PJ

 

[DrEntropy]

Yup. Black sooty exhaust is a too-rich indication. Dave and Paul's suggestions are what to check. Stuck choke or float/needle valve problems are the most likely candidates. There's a 'valve' in the float bowl that can do some odd things to the mix as well if it gets cruddy. "Full power needle valve" or something like that.

Which choke gizmo does that thing have? Manual, water or electric?

 

[MGZT260]

Seeing the other thtread concerning 3 and 4 plug wires having no effect on running when removed may indicate fuel richness is symptom of electrical problem in ignition sequence.

 

[terriphill]

A dumb question: is the front side cover clogged?

And the winner is..... Tony, we pulled the side cover today and guess what...full of black yucky gunk! We never knew to remove this cover when we had the motor out and were cleaning it up. Let's see what happens if we clean it all up.
Man, I feel like such and amateur! (oops, that's what I am LOL)

 

[tony barnhill]

Teri - it will still probably blow oil if you don't readjust your carbs after cleaning that side cover.