Sounds like a sparking problem on one plug. It could be a bad wire or plug. Maybe the wire is laying on the exaust manifold.

 

Or a cracked spark plug ceramic...?

Lets Wheel !

 

Or a bad idle circuit. While the engine is running, kill one cylinder at a time by shorting out the plug wires one at a time. Notice if the idle drops off as you move through the cylinders. If the engine rpm does not drop off then the cylinder is dead, or has some compression problems. If the rpms drop off equally on all cylinders then start looking for Vacuum leaks around the intake manifold or idle circuit in carb or maybe the distributor is not dropping down its weights.
Good luck, mine runs very smooth at idle.

 

Ok thanks for the replies. Ill try the plug route. I have newer plug wires and new plugs in er. I rebuilt the carb and put new manifold
gaskets too. The engine runs smooth, with no hesistation at all. It never dies on me, and it always starts right up every time.
I pulled a couple of plugs and they look nice.
I guess I should do compression check and check all of the plugs while I am at it. The only thing that I noticed is that it seems
to miss a little out the exhaust. There is a faint sputter for lack of a better word. It is not a constant exhaust exit tone. Maybe it is time to
put in a new distributor and upgrade it to HEI.

If you see this put your .02cents in.......................Thanks

 

WOW! DC is checking up on us Jeepster types. Check out the third post. None other than the Honorable Janet Reno. Click on the name and you'll be able to click on to a sight for Janet Reno. Wonder if the poster is the real Attorney General or not? I get a kick out of the bio in the Off-Road.com profile.


Tim
'66 Jeepster Commando w/Buick 252/4.1L V-6
'70 Wagoneer w/Buick 350 V-8

 

Most of these type problems reflect the need for a tune up

used jeepster parts.

 

Rough at adle only, fine every other speed?

Sounds like a typical vacuum leak. Pinch off all vacuum hoses looking for an RPM change, should be none.

Lean the carb mixture screws (in) till it's much worse. Spray a flammable carb cleaner around manifold, power booster, trans modulator, and carb base. Test the cleaner to make sure it burns by dribbling a couple of drops down the carb, if RPM INCREASES after you are puposely lean, it's the right stuff. Most carb cleaner doesn't work right for that purpose. Propane or starting fluid works too.

Look for an RPM change.

To test to see if HEI will help, try opening the plug gap .005 more to .040. The wider gap smooths idle with the longer spark. Standard ignition may misfire under load at that gap - not enough poop, so it's just a test to see how HEI will affect your idle.

 

ok thanks Ill try the carb cleaner too. Hey I was just thinking about the tuneup and I remembered that I had
problems getting the right spark plug for the Jeepster. I went around and around with parts store guy
about the spark plugs on my Jeepster. His computer/book showed a long reach plug and the ones
that I have were short reach. I am running Autolite 85 right now. Is this the right ones?


If you see this put your .02cents in.......................Thanks

 

Stick to stock AC plugs if you want it to run like it should.
GM designed Buick engines around the AC plug, other brands experiment with thier stuff till they find one that MAY work.
Stay totally away from imported trash, like German or Jap junk. (Parts houses like to promote them because they cost them almost nothing.)
No platinum, split fire, or other "performance" plugs that don't do what they are supposed tio do either. (Pink)

Just use original equipment standard heat range AC plugs in GM engines.

If Accel ever builds an engine themselves, then it would be appropriate to use Accel plugs in it.

If your parts house doesn't have AC plugs for your engine (a common number,) RUN AWAY!

 

I agree with RRich. It's probably a vaccuum leak. My rig shook just like you described. I had a leak near the back of the engine, no hose at all and not plugged either. My power booster also has a leak. I fixed the engine leak and unplugged the vaccuum hose on the booster and now I am running smooth.