Hi all, I don't post here often, and I'm kind of new to the older cars thing. So this might be a dumb question. I have a 1964 Rambler Cl***ic (daily driver). She's got 44,000 miles and starts and runs just fine. I've noticed though that when it's at full operating temperature, the idle gets really low/rough, sometimes to the point of stalling out at a light (but will start right up no problem). I've messed with the idle speed screw a little bit, which doesn't seem to really change anything. Do you think it's an oil pressure problem? Should I switch to a higher-viscosity oil? I use 5W30 right now. Any thoughts would be much appreciated. Thanks.
First thing I would look at is the total tune. Check the timing, spark plugs, wires, etc. When an engine begins to idle rough and die, I always try the simple things first.
If you messed with the idle speed screw it should've at least raised the idle speed, even if it didn't make it smoother. However, there's an idle mixture screw on there somewhere too. Find it and try turning in or out 1/4 turn at a time, but keep track in case you make it worse and need to return to where you started before bringing to a pro
Thanks guys. I know the timing is good. The wires were recently changed as well as the points and condenser and distributor cap. I know it does need new spark plugs, which could definitely be the problem.
Mine does the same thing but it goes away if I start driving faster. I am over due for a carb rebuild though. Some guys have suggested marvel and it has enabled me to survive without one however mine is not a daily driver.
Ok...if you "messed" with the idle screw and it did not change anything.... Sounds like a vacuum leak .. Something is opening up when it gets to temp... Dave Posted using the Full Custom H.A.M.B. App!
Sometimes on older, plugged carbs the idle "mix" screw can be non responsive. But, the idle "speed" screw should always do something. That said, you should have someone else take a look.
I would think the needle and seat in the carb has crud. The same thing happens to my Pontiac. If you have a rubber fuel line, pinch it closed. This will cause the fuel level to drop in the carb. Release the fuel line, fresh gas pouring p*** the needle and seat will flush out the crud. You may get away with pulling the top off the carb and cleaning the fuel bowel. If anything, it will let you know how much crud is in there.
If it has the 232 six check all the manifold bolts, including the ones that bolt the intake and exhaust manifolds together. You should loosen the bolts that bolt the manifolds together then tighten the manifold to head bolts starting with the four in the center then working to the outside by jumping from front to back. After those are tightened tighten the four holding the manifolds together. Also check and make sure the exhaust heat flapper isn't stuck shut. That will cause problems! Either free it up or wire it open. Wiring open will make the engine a bit more cold natured and take a bit longer to warm up, but it will run fine once warm. If you have the 196 (carb is on a plate on top of the head, close to valve cover) just make sure the carb and the plate screws are tight. It's easy to wring off those little 1/4" bolts holding the plate on, so be careful!
Did you ever fix it? Your thread inspired me to rebuild my carb. My carb had a bowl full of crud and the pump was crooked and probably not working properly. I am still in the process of fine tuning. Good luck!
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