I recently purchased a 1987 pickup with 89,000 miles. The dist. cap, rotor, plugs and wires have all been replaced and the timing has been set. The motor has a skip in it that is most noticeable when traveling at a constant speed and when starting off in low gear. The truck has good acceleration but when you let off the accelerator a little bit it begins to skip. It is also a little difficult to start. The truck is a 4 spd. 2wd. An older gentleman owned the truck and I suspect it didn't get used much given the mileage. All along I felt it was a carb. issue but it needed tuning also. Any help with diagnosis and possible solution would be appreciated. Thanks.

 

Spray a liberal amount of carb cleaner around the base of the carb, try to note an idle change. I had a slight starting issue (especially when cold) with my Weber that was caused by a leaking base gasket.

Also Ignition timing should be set at 0 degrees with both vacuum lines plugged and off the distributor with the engine idling no more then 750rpm.

IMO this is more of a vacuum issue then a carb issue since you have no issues accelerating.

 

I will try that as soon as I get a new fuel filter on it. I have the old one off now. Thanksl.

 

I tried what xxxtreme said and it did change the idle. But in the process I found a vacuum line off of the right front side of the carb. I put it back on and repeated the process and the idle did not change. After driving it seems some better but the skip is still present. It was also idling rough before I shut it off.
Any more ideas?

 

If that line was off chances are the idle was high and readjusted, and now that you fixed that vacuum leak it's idling lower. Raise your idle via the idle screw. Double check your ignition timing and make sure it's set at 0 degrees.

 

Started it about 30 minutes later and the idle was better. Will re-check timing. Thinking a carb. rebuilt kit may be next. Thanks. I will post the results.