I have been fighting this engine for about a year off and on. It has a small cam and lt's. I got the car from a friend about a year ago and it has run badly for about 3 years before that( started with the cam install ) and he could never figure out the problem. When i got it I put a new distributor, fuel pump, spark plugs and wires, and a different q-jet ( I know the carb is wrong, because there is no hook up for the tv cable, but I just wanted to see if it would run better). The problem seems to be a miss fire. It does not idle well and will die when put into gear ( could be the fact the tv cable is not hooked up) and i am getting a pop out of the exhaust when idling. I will warn you that this is my first car without fuel injection so I don't know a lot about it. I was told the engine has under 1k on it and the compression test I ran was vary good. I am at my end with this engine and am about to drop a piece of crap chevy 305 in it.
I have messed around with the timing a little, but i will admit that i am still learning about working on engines. Would the pop be do to the timing being to advanced or to retarded. When I have turned the distributr while running I just try to get the idle to smooth out. Is there something else I can listen for outside of it being really off? I have just started reading about timing in the Buick FAQ section and i am going to try and get it timed right myself.
Do you have a Tach. hooked up to the motor?Sounds like your timing is retarded too much.Try turning the distributor counter-clockwise a little and see if the RPM's come up .If you can get it to idle ok then you might want to adjust the idle screw out a little to bring the RPM's to around 800 in Park.Without a tach and a timing light it's kinda hard to get it exactly where it needs to be.If you have a vaccum gauge you can advance the timing to where you get the highest reading and that will get you in the ballpark also.
you know, i just thought of it but a few years back my brother bought a 72 chevelle and it would back fire when u just stepped on the gas a little. Im betting youre having carb issues. I'd find out what carb you have, get the #'s and go get a carb rebuild kit and give that a try.
This sounds like a good place to start :TU: . I have a tack in the car, but it hasn't been working. Maybe it is not hooked up to the distributor at the moment. As Far as the carb goes, I don't think that is the right one for that car at all. I also don't think that is the right chock ether. I am going to have one of my friends bring another one out that should be right for the car. Thanks for the all the help. I will keep you all up on what happens.
Make sure your plugs are wired correctly Since it "started with the cam install", I would bet the cam timing is wrong. However before you open the engine here a few more things you can check on the top: 1. The pop you are hearing is unspent fuel lighting off in the exhaust manifold. If that is happening I doubt it is carberation. The pop can be caused by two spark plug wires misrouted to the wrong plugs. Often one of the plugs will fire when during the exhaust stroke. If you've run it like this for long it will burn the valves. The easiest way to check this is to find the terminal for the first cylinder on the distributer. Then go around the distributer and make sure it follows the pattern 1-8-4-3-6-5-7-2. Note buick numbers its cylindrs differently than ford and some other makes. The drivers side bank is 1-3-5-7 front to rear and the passengers side is 2-4-6-8. 2. If they are all wired correctly, then I would look at the ignition timing. If you are running a stock distributer and advance setup then it should be set to 6 degrees with the distributer vacuum line disconnected. 3. Test the the coil (or just replace it) if you haven't already You have replaced the rest of the ignition components, so you have pretty much addressed all the potential problems without opening the engine (assuming the new plugs and wires you got are good). I would continue as follows: 4. I would pull the front cover and check that the cam is timed right. I always keep the cam "straight up". If you want to run an advanced or retarded cam others here may have tuning reccomendations, but if it is straight up you should have a known starting point that will work. 5. After this the next thing to look at is the valve train. Pull the rocker covers and make sure the rockers are on good and are not bent/twisted. Look for excesssive play/lash on the pushrods and make sure none of the valve stems are bent. If you can check the spring compression.
This is exactly the same problem I'm fighting but not for that long. It idles decent, put it in gear and it dies. I'm sure my problem is a vaccum leak which started when I changed intake manifolds. The quickest way to check for a vaccum leak is to start it and let it idle, then push the choke about half to three quarters closed. If the idle speed picks up you have a vaccum leak.Good luck! Dave B
