Engine: Rough running need help

[Lark289]

[Warren Webb]

Being a body shop is a dusty enviroment have you checked the air filter? That would answer for the low idle condition. As far as the distributor hold down bolt I use a distributor wrench from Harbor Freight. Cheap & reaches under the distributor. Perhaps too check the exhaust system. Not being related to the body shop but perhaps the muffler has taken the time to collapse, which would restrict exhaust & cause all sorts of performance problems.

[Lark289]

Being a body shop is a dusty enviroment have you checked the air filter? That would answer for the low idle condition. As far as the distributor hold down bolt I use a distributor wrench from Harbor Freight. Cheap & reaches under the distributor. Perhaps too check the exhaust system. Not being related to the body shop but perhaps the muffler has taken the time to collapse, which would restrict exhaust & cause all sorts of performance problems.

Air filter is new too. Thanks for the suggestion about the distributor wrench. I completely forgot about that type of wrench. That would have made the job soooo much easier. I must add one to my tool collection.

[Orestudeguy]

Not knowing what type of work that you have had them do. Is it possible that they put it on a lift, or placed a jack in the wrong place and
partially collapsed a fuel line?

[jclary]

Check your vacuum advance diaphragm. They can fail without warning and cause rough idle as you describe.

[Lark289]

Check your vacuum advance diaphragm. They can fail without warning and cause rough idle as you describe.

When I rev the engine I can see the timing change (using my timing light) so I think the vacuum advance is working.

[Mike Van Veghten]

When you rev the engine, the timing changes....that only means...the mechanical advance works..!
When "reving" the engine...the mechanical advance will advance the timing. When you step on the throttle (depending on how the vacuum is connected..) the timing will "drop" if it's connected as the factory had it. Or at idle, the vacuum advance will be in full...but when you hit the throttle, the vacuum will drop while the mechanical will raise.
Or...if you have ported vacuum...enough timing school for now I guess.

This isn't normally a "sudden" thing, but then again, sudden...means different things to different people.
Check the valve adjustement. If you haven't done it within about 3500/4500 miles, the exhaust valves could be tight and causing your rough running. That won't normally cause an engine to die when put in gear...but along with other small things, it just might.

Mike

[PackardV8]

When I rev the engine I can see the timing change (using my timing light) so I think the vacuum advance is working.

Not conclusive proof. The centrifugal advance comes in as the engine revs up. Only way to check the vacuum diaphragm is to disconnect the line from the intake and pull a vacuum on it with a pump or old school, with your mouth. If it holds a vacuum, it is good. Any leakage at all, replace it.

jack vines

[bige]

Was it in the body shop for a long time? May be a sticking valve.

I would check or just replace the intake manifold gaskets and the clamps under the bolts. My preference is the fiber style gasket. Intake leaks can wreak havoc on idle and are impossible to adjust around. It's such an easy job on the Stude. Those manifold clamps weaken and crack and lose their clamping ability but it's not always obvious.

Another easy thing to do is disconnect evrey vacuum line and block it off. If the idle improves reconnect one at a time looking for the culprit.

When you check the timing is the mark steady or does it jump around? If there's a lot of movement you could have worn distributor bushings or two plug wires arcing against each other.

Also, I remember a thread where an adjustment at the transmission cured an idle in gear problem. Maybe Jack or Mike can chime in on that.

ErnieR

[warrlaw1]

Fuel? Mine ran like crap after 3 months winter storage. Even with stabill in the tank, there was stuff in there that shouldn't have been. Run a line from a bottle of gas and see if that gives it its power back.

[PackardV8]

Fuel?

X2 - I chased a rough running problem on an Avanti for a week. I didn't think to ask and the owner didn't tell me the fuel in the tank was two years old.

jack vines

[willieb6]

To: jclary Glad to see someone from Greer driving Studebakers, born and raised in Greer. still have a bro. and sister alive living in Greer. Have mess with old cars for 50 years and own several Larks and Hawks. Have a 61 Hawk now. sold a 50 olds to a guy that own a upholistery shop on Hy29 going towards Greenville about 3yrs ago. Just glad to see someone from the old home town. Bill Bailey, Deland, Fla.

[jclary]

To: jclary Glad to see someone from Greer driving Studebakers, born and raised in Greer. still have a bro. and sister alive living in Greer. Have mess with old cars for 50 years and own several Larks and Hawks. Have a 61 Hawk now. sold a 50 olds to a guy that own a upholistery shop on Hy29 going towards Greenville about 3yrs ago. Just glad to see someone from the old home town. Bill Bailey, Deland, Fla.

Welcome to the forum Bill. I have been driving Studebakers around Greer since 1975. If you get back this way, give me a shout.