Warm up transmission

Maybe its just that I'm paranoid and dont have enough experience driving old cars, but after warming the engine up for 15-20 minutes I notice that it usually starts out really hard to get past 20 mph until I've driven it around the neighborhood a bit and "warmed up" the transmission.

Until I slowly cruise around a bit, it seems giving it too much throttle results in what I can only describe as it trying to choke out. It doesnt sound like its going to stall but the engine stops trying to turn and acts like its stuck. Until I back off the gas and push it again, then it will usually start moving. Once ive got things moving for a decent amount of time though it runs like a champ.

Originally I chalked it up to the engine still being too cold, but now that I think of it, it makes more sense that the trans isnt being warmed up until it moves.

Is this just normal for old cars or should I be concerned about my transmission?

Alot of this is new to me but im trying to learn.
 
Chances are the choke (on carbuator) is stuck or not opening at the right rate. This will cause a bog Trans sounds fine You do not have to "warm" them up. PM your phone number I talk better than type. Had many 60s Cadillacs in the day bought a new one every year from 62 to 71.
 
Couple things to check.
1. Make sure that the choke is working properly.
2. Transmission linkage and the switch on the carburetor is properly plugged into the wire harness.
4. Transmission linkage is not out of adjustment.
5. Did they check to see if the transmission vacuum modulator is not leaking, and that the rubber vacuum hose from the intake manifold to the vacuum modulator has been replaced. There are two 6" approx. rubber hoses that connect the vacuum modulator. One at the modulator itself, and the other at the end of the metal line that goes to the transmission, and joins at the carburetor or intake manifold. Vacuum leaks can cause you a lot of grief, but are relatively easy and inexpensive to repair.
6. Engine timing must be set exactly as it is explained in the FSM (factory shop manual). There are exact instructions on what vacuum lines need to be unplugged, and capped so they don't leak vacuum. If the instructions aren't followed exactly, the timing will not be set where it should be. Vacuum effects a lot of things on a car, and sometimes it is difficult to diagnose.
 
jump in start the car as soon as it fires and is running drop it in gear and go. idling the car is very hard on it and not a good practice. you are problem just loading it up with raw gas. the transmission after 20 minuets of idling will be at normal operation temp.not necessary at all. now at 0 out they will be a little stiff
if they are sitting out side but it only takes a mile of two to have them warmed up. just take it easy off the start and go.
 
Chances are the choke (on carbuator) is stuck or not opening at the right rate. This will cause a bog Trans sounds fine You do not have to "warm" them up. PM your phone number I talk better than type. Had many 60s Cadillacs in the day bought a new one every year from 62 to 71.

Will PM you, I have some time during lunch

Couple things to check.
Engine timing must be set exactly as it is explained in the FSM (factory shop manual).

I unfortunately dont have the manual, but I will look at the items you mentioned

jump in start the car as soon as it fires and is running drop it in gear and go. idling the car is vary hard on it and not a good practice. you are problem just loading it up with raw gas. the transmission after 20 minuets of idling will be at normal operation temp.not necessary at all. now at 0 out they will be a little stiff
if they are sitting out side but it only takes a mile of two to have them warmed up. just take it easy off the start and go.

I have been warming up in park, i will try this and see if this is part of my problem or not. I appreciate all the input.
 
the fluid cycles thew the radiator. as that is were the trans cooler is, as it warms up so will the transmission. plus it has direct contact to the engine block.

the standard trick was to let it fire and then pick up the speed enough to let the engine clear out the raw fuel.l you don't have to race the engine at a high rpm just pick up the speed till it smooths out and will drop back to the high idle and run smooth. then you should be good to go. if it bulks and stumbles when you but it in gear there may be problems with the choke. or in the settings of the engine. Pet maybe able to talk you threw the trouble shooting of things.
 
I havent quite figured this out yet but im guessing it probably choke related. Previously it had only happened when I first start driving, but Wednesday I drove it 45 minutes from Tulsa to Owasso and a few times while steadily driving 40 or so it happened, engine kinda starts cutting and acting like its about to choke out.

The only way to get it to stop is to let off the gas completely then hit the throttle again on and off a few times until it clears up and starts running smooth again.

in my limited knowledge I wonder if its possible that somehow the choke flap is falling down and closing while the throttles down?

Aside from this its been driving pretty good, its just doing this every so often. When I have some spare time I may just eyeball the choke and see how freely the choke moves. My mother in law told me to spray some carb cleaner on it, but if it was a remanned carb I shouldnt need to do that i'd think. My mother also suggested I put a "heet" additive into the gas to prevent water buildup.

I have done neither yet
 
Gasoline today has ethanol in it, so "HEET" isn't going to do anything. As for spraying the choke mechanism with carb cleaner, if the carburetor was rebuilt, it shouldn't need to be cleaned. To me, I would be questioning the person that did the carb rebuild as to why there is an issue. There is no way to justify the quality of someone else's work unless you have the ability to assess it in person. Having said that, I have seen lots of "hacks" that claim to know how to rebuild carburetors but know next to nothing about how a carburetor works, or what to look for when there is a problem. From memory, your car is a 1968, and that has a Rochester Quadrajet carburetor, which is extremely complicated/sophisticated, so rebuilding it correctly is best left to the person that rebuilds them all the time, not a "jack of all trades".
 
It hasnt been rebuilt yet. I have the original in a box in the coach, they put in a remanned quadrajet. I'm probably going to give them a call. While at this point I dont want them messing with it more, they did say if there was a carb problem they would look at it no charge since they put it in
 
the one thing with the q jet you got to watch is over tightening the air cleaner nut.. it will pull the center of the top up and cause choke problems. but that would be a start up issue. not a run problem. it could be a low vacuum condition that lets the power valve pull open. normal if they have the float adjusted to high you get the problem your talking about rounding a corner. gas will slop over into the the intake and flood it out.

easy check for a vacuum leak is with a small propane torch. with the car running at idle, just crack the valve on the torch and run it around the base of the crab and the fittings and intake. if it picks up RPM you found a leak. needless to say you don't light the torch.

rebuilds are a problem as they will use parts off a number of different carbs to get one out the door. one other thing you can do is swap, put the original one back on if the problem changes or goes away you know it is a carb problem.
 
This is getting silly and costing money. My 68 Cadillac I bought new was a great car and I have had many 68s since including many Pro Cars this is not a troublesome year. The premo Carburator rebuilder is Larry Isgro Carburetors

1604 Argyle Rd,

Wantagh, NY 11793

(516) 783-1041 He as done my Packard Caribbean 2 4 barrels and others for me. Check his ratings on Google.
 
For other carburetor rebuilders, please check the recommended vendors forum. There is one person in Arizona that specializes in rebuilding the Rochester Quadrajet carburetors and knows them so well that he can identify the carburetor by just looking at it. This is the type of master carburetor rebuilder that you want to use, especially, if your carburetor has missing or miss-matched parts.

Carburetors Unlimited
7942 W Gold Dust Ave
Ste 3,
Peoria, AZ 85345

(623) 388-0990

http://www.carburetorsunlimited.com/
 
This is getting silly and costing money. My 68 Cadillac I bought new was a great car and I have had many 68s since including many Pro Cars this is not a troublesome year. The premo Carburator rebuilder is Larry Isgro Carburetors

1604 Argyle Rd,

Wantagh, NY 11793

(516) 783-1041 He as done my Packard Caribbean 2 4 barrels and others for me. Check his ratings on Google.

The reason im taking it back to the guys that installed this carburetor is because they will work on it free if its a carb issue. If they say its something else besides the carb then i will get a quote and walk out with my money for now. Cant really afford to throw money at it right now anyway. I figure as long as they will do carb work free I will let them take a free crack at it. If they figure it out and fix it, great. If they say I have another problem then at least I can take that info elsewhere.


For other carburetor rebuilders, please check the recommended vendors forum. There is one person in Arizona that specializes in rebuilding the Rochester Quadrajet carburetors and knows them so well that he can identify the carburetor by just looking at it. This is the type of master carburetor rebuilder that you want to use, especially, if your carburetor has missing or miss-matched parts.

Carburetors Unlimited
7942 W Gold Dust Ave
Ste 3,
Peoria, AZ 85345

(623) 388-0990

http://www.carburetorsunlimited.com/

Thanks, I will look into that. I do plan on getting the old one rebuilt.
 
Took it back in this morning to take advantange of the carburetor warranty. If the problem is carb related it will be free of charge. If its anything else I may just grab an estimate and hopefully leave with more info than I had before
 
Shop told me that they found the cause. They say i was running rich and my plugs were fouled. They said my auto choke is not working properly and that alot of old cars had auto chokes that didnt work well.

They recommended installing a manual choke, which they are going to give me an estimate for.

Im not sure on the manual choke. Why not fix the auto choke? In any case i cant afford anything at the moment, so i will at least get my quote. They are making adjustments to the carb though
 
68

Fix the auto choke , they worked fine when new and can work the same if repaired correctly. If you can get by , have them set the choke fully open. It will be harder to start cold but you might get by with a few extra pumps on the gas pedal to enrich for a cold start. Worst case is a shot of starting fluid with a inop choke. Or just let it sit until you can get the carb rebuilt correctly.
 
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