Ruff Idle problem
 

Have a problem with my 29 huckster with a ruff idle. It sounds like when a person has the GAV screwed out to far. Like it is getting to much gas. Also when I screw the GAV all the way in it still has the same problem. Spark plugs are black and when first starting, it leaves black stuff on the floor out of the exhaust.


I replaced the carb with another carb I had that was a good carb. Still the same problem.

Have not done anything to the distributor yet.

Any ideas would be appreciated.

Re: Ruff Idle problem
 

Are you running an air filter? Is it dirty?

Re: Ruff Idle problem
 

No not running with an air filter.

I did put on a new intake manifold gasket thinking I had a leak but this also did not improve problem.

I still have not replaced the distributor or spark plugs. This may be my next step.

Could the problem be that I have not driven the rig on a long drive lately? I just got a new battery in it and got is started after sitting all winter. Have not taken it out for a long drive yet.

Re: Ruff Idle problem
 

I would get some fresh gas, mmo, clean your plugs and go for a nice long drive :-)
Lean out the gav, advance the spark a little more than normal. Enjoy your ride!

Re: Ruff Idle problem
 

Running way to rich.

Re: Ruff Idle problem
 

After you clean the spark plugs, install new points, clean the cap and rotor, check for full voltage at the coil, and replace all the fuel, look down the air cleaner side of the carburetor while it's idling. If you see any liquid gas moving, the float or needle and seat need work. Reason: all the fuel at idle, enters the air stream beneath the carburetor's butterfly. You should not see any gas moving at an idle. If the carb's insides are relatively dry, at an idle, the idle air/fuel adjustment screw should make a difference in idle quality, unless there is blockage in one or more passages inside the carb.

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Re: Ruff Idle problem
 

You mention playing with the GAV, but, not the idle mixture screw. Thats what its for.

Re: Ruff Idle problem
 

I did work with the idle mixture screw also and it did not seem to make any difference. But I am one that knows little about how to solve this type of problem so I will have to try this again.

Re: Ruff Idle problem
 

Will have to try your ideas. I use no crap gas but it still could be messed up. So will try some fresh gas and take it for a run. Will have to get some mmo and try to clean the plugs.

Re: Ruff Idle problem
 

It sounds as though the carburetor needs a cleaning.

Re: Ruff Idle problem
 

if the idle air screw dont make any diff. something is plugged up. spray some carb cleaner in after taking screw out with eng running and it might clean it out. if not I would take carb apart and clean it real good

Re: Ruff Idle problem
 

I put on another carb yesterday and it did not make a difference-still same problem. Put my old "B" carb on today-still the same problem. But what I did not do was to put a new gasket between the carb and intake manifold-use the same old one every time I put on a different carb. I think I will order a new gasket and see if that helps

Also today I tried to clean the spark plugs which were black with quite a bit of crud on them. I used an old tooth brush to clean them. Anyone have a better way to clean plugs? Spark plugs cleaned still did not help the problem.

I also used a different distributor body, cap and rotor. Did not change out the points. This also did not solve the problem. So only thing I did not do with distributor is change out the points and condenser. May try that.

Anyone have any other ideas as to what to do? I still have not taken it for a long drive yet-typical Oregon weather-rain! Could it be sticky valves?

Re: Ruff Idle problem
 

Maybe you could reset your timing , runs ruff if it is
off!

Re: Ruff Idle problem
 

Good point Ronald. I did do some adjustment on the timing when I first started it up this spring. But you may be correct because I noticed that moving the spark lever up and down did not make much difference in how it ran. So will have to try that. I am not a good timer so will have to play around with it to try to get it better.

The other thing maybe I should do is change out the distributor. The one I have in there is a long shaft one. I think I have a short shaft one in the shop that I can swap out.

If I ever get this problem solved, I will let you all know what worked.

Re: Ruff Idle problem
 

Update on latest stuff I tried on this rig.

Pulled distributor and replace with one that was rebuilt with all new parts. Timed rig and set points, put in new spark plugs--still have problem.

Sill things suggested by you all that I have not done are: Use MMO to see it that would correct it, take it for a long run somewhere, and have not completely replaced the gas (ran out of gas cans to drain).

Just purchased some MMO. Question I have is how does a person use this stuff. Do you just put it in the oil, put it in the gas, pore a bit in each cylinder or ???? Could use some ideas on MMO.

Thanks for putting up with me on this problem.

Re: Ruff Idle problem
 

4oz/10gal gas.

4oz/4qt oil

It will not hurt to introduce some in each cylinder. I wouldn't drown them, but maybe a tablespoon worth in each would be sufficient. Be sure to turn the motor over a few revolutions to let it move around inside before putting the fire to it and burning it all out.

My wooden nickle worth.

Re: Ruff Idle problem
 

Thanks RawhideKid. This helps a lot. I have not used this stuff before and it may do the job. With all the things I have already done and have not fixed the problem, it would seem logical that maybe a valve or something like that is sticking. So maybe this stuff along with a long run, may fix the problem.

The way the engine sounds at an idle makes it seem like every now and then, a piston just does not fire. Not a regular thing but seems like it just does it every now and then. Rig runs OK when you take it down the road and let it run.

Re: Ruff Idle problem
 

I would try shorting out spark plugs one at a time and see if there's one that doesn't make much difference in the running. Then change that plug.

Re: Ruff Idle problem
 

Have you got one of those voltage testers like brattons 17150? You stick in the rotor cap with the coil wire into it upper end. Then you can increase the spark gap and watch it spark, watching for misses. Also a clear rotor cap, or a cut down one will work as well. It has helped me find an erratic spark before.

Re: Ruff Idle problem
 

Hooray! Rawhidekid "hit the nail on the head". I put about a tablespoon of MMO in each cylinder, turned the motor over a few times, put the plugs back in, and started it up and WOW, it ran and idled like a Model A should! It idled great with the spark either up or down, had a lot of power while taking it for a run around the block (that is all of a run I could make because of good old Oregon rain). I will also have to get some MMO in the oil and gas like Rawhidekid mentioned.

Now I have a rig that runs the way it should, has an upgraded carb on it, has a rebuilt distributor and apparently has the valves freed up. So once it stops raining around good old Oregon, I will have to take it for a longer run.

Thanks to you all for the ideas and the help to get it going again.