So yesterday I bought my FIRST car. (I mean actually purchasing from a private owner with cash, not financing from a dealer) It's a beautiful 1972 Buick Skylark 350/2 5.7L V8 4DR. I know nothing about old cars. I'm a Diesel engine mechanic, not a gas engine mechanic. So here's my issue, and I'm wondering if it's normal or not. First, I have to let the car run for 10 minutes before driving. If I don't allow it, it will stall and die MID DRIVE when given gas in drive. Totally works in reverse though...? Second, when it does finally "warm up" enough to go without stalling, it hesitates when given gas and pulls like crazy. Almost like it second guesses itself and then races to catch up. It also does this when making turns, especially. I am completely able of tearing this mother effer apart and rebuilding the engine. With that being said, I don't like mechanics haha and I'm trying to stay away from one for as long as possible. I've got some sea foam to throw in the gas tank as well. What I really need is someone to explain to me why this is happening, or even what to check. The car is great. Absolutely amazing smooth ride. Nice and loud, powerful. The steering is very very very loose but nothing crazy. Any help would be appreciated!
The 1972 Buick 350 engine had some calibrations with emissions in mind. First, the carburetor was calibrated leaner to work with heated intake air. There is a 2" diameter tube running between the driver's side exhaust manifold and the air cleaner. That tube in conjunction with a blend door in the air cleaner snorkel ensures that air inside the air cleaner stays around 115*. The choke is also calibrated with leaner settings. If the tube is missing or the system is not functioning, it will cause hesitation and stalling ESPECIALLY in cold weather. Secondly, there is an emissions device called "Transmission Controlled Spark Advance (TCS). It shuts off vacuum advance to the distributor in 1st and second gears, and restores it once the transmission has shifted into 3rd gear. It will also restore the vacuum advance in reverse gear. That may explain why it doesn't stall in reverse. Bypassing the system is easy, just remove the electrical connection at the Thermovacuum switch screwed into the front driver's side of the intake manifold. Thirdly, if the engine still has the original distributor from the factory, part number 1112109 (it might not), and it is timed initially at 4* BTDC, the ignition timing is retarded for best power. That distributor has between 12 and 16* of mechanical advance. That means it has between 16* and 20* of timing at wide open throttle. Optimal is 32*. Read my thread on "Power Timing" http://www.v8buick.com/showthread.php?63475-Power-Timing-your-Buick-V8 Bottom line is your engine may just need a bit of tuning to make it run A LOT better.
wow thanks for the awesome response. So what's your advice on how to go about this? Just get a carb cleaner or what? I was told it could be the choke locking up and like I said, I don't know anything about these cars. I need everything explained to me like I'm a dummy (because for the most part, I am)
It really isn't very practical to explain everything to you, but what I would recommend to you is to buy the 1972 Buick Chassis Manual. That will be a WEALTH of information to you. Here is one on E Bay, http://www.ebay.com/itm/Original-19...ash=item488512e334:g:RqwAAOSwl9BWKUpE&vxp=mtr You can also get it on CD ROM, http://www.gearheadcafe.com/General...-Shop-Manuals-CDrom-Fisher-Body-Manuals-CDrom First check to see if that 2" diameter tube is there in the engine compartment. It will connect between the exhaust manifold and the air cleaner. If it is missing, that is one part of the problem. I would also check the ignition timing. You need a timing light for that. Borrow one or buy one. Carburetor cleaner won't hurt, but I doubt that is your problem. Does the choke work? Does the engine race when it is cold? If you are a diesel mechanic, you have to have quite a bit of mechanical aptitude. Learning to work on gas engines, especially older ones should not be very difficult for you. The chassis manual will help you a lot. Get one and read up.
It may need a accelerator pump as well this gives the carb shot of fuel to get it going Larry is a great tuner so his advise is worth taking
This is probably the best information I've gotten so far. I work on generators, not vehicles so it's a little different but an engine is an engine. As for the manual, hell yeah. But is there anywhere I can get it electronically? And what do you mean does it race?
If you join here, http://www.teambuick.com/forums/forum.php They have some manuals posted online, but not a 1972. The 71 manual is similar. You really need your own copy though. The automatic choke on the carburetor provides richer mixtures when the engine is cold and while it warms up. The choke closes the choke blade across the throat of the carburetor when the engine is cold. This also rotates a fast idle cam to increase idle speed at the same time the choke is on. Normally, you set the choke by flooring the gas pedal once or twice before cranking the engine to start. When the engine starts, it should fast idle (about 1500 RPM). If it does not, that could mean the choke is not operating as it should.
I can't actually tell if it does that. I'll check it out tomorrow. The thing is, it doesn't have an RPM gauge haha It usually doesn't have any problems starting. Even when idle, I give it gas and it starts to lag and stutter. If I hold the gas while in park, it WILL stall. So it's not only in drive. So so ill start it tomorrow and see what I hear
Well, that sounds like a fuel problem to me. You are going to have to do some testing. Could be a lot of things. Fuel pump, fuel filter, bad rubber lines, clogged pick up, or the carburetor may need rebuilding.
You may also want to post your location. Help may be right around the corner and you'll never know, and neither will anyone else on the board. You don't need a tachometer to tell the engine is fast idling as it should when cold.
Heres another thing about that. Some of the gas in there has been sitting for 5 years. And the gas I put in it isn't high enough of an octane rating. Could that be a factor? Ive been doing some research and now everything makes sense haha I'm thinking maybe a MAF...if it even has a MAF? Im so new at this it hurts
Alright so I tried again today. Let it warm up for about 5 minutes. I didn't hear any fast idling. It started its first try. AND it died in reverse as well. So it will die in reverse. I looked down the carb and I didn't see anything. No fuel nothing. Both when it was stopped and when it was running. I couldn't see anything. I think I'm too new at this **** to try to fix it myself. Plus it's freezing all day where I am now. Im gonna drop it off at the mechanic when I come back home in June.
I'm betting it is an accelerator pump and/or the choke. If it doesn't have a choke that works, it will be a pain until it reaches operating temp. If it still stumbles after it warms fully up, I'm betting more toward accelerator pump. That's what provides the extra gas for a burst because the air is lighter and gets flowing sooner than the venturi delivered fuel.
Yeeks, 5 year old gas? Must drain that out either by siphoning, or pump before you go any further. Putting fresh gas in with old stuff doesn't make the old stuff good. As Larry stated there is no substitute for a hard copy of shop manual. Online version is Ok for doing spot checks but it really isn't practical when you are working through problems. Best money you will spend.
Alright so a little update. I now know the car will die in reverse. I also heard the fast idling when I first started the engine. Still will stall when given gas though. I warmed it up for about 15 minutes, then I observed the throttle. I saw two healthy squirts of fuel into the carburetor. It also looks like a puddle is sitting inside of it...? Didnt try to drive it today because it was too cold and I just replaced the turn signal. Would a youtube video better help you guys understand what's going on or is it pretty self explanatory? It sounds like too much air not enough fuel until warmed up. Next step is to siphon the gas. Fill it with premium and sea foam and see what happens then. heres another weird thing...This stalling seems like it has a "sweet spot". If I tap the gas, all good. If I floor the gas, all good. It's when I hit that sweet spot is when it starts stalling
Sitting for five yrs, you're carb is full of crap, meaning the gas that was in it turned to powder cake n flake stuff. If it's too cold to wrk out side it's perfect to pull the carb off buy a manual and rebuild that thing in the kitchen. U can get a can of carb dip . Or hell I still use my dishwasher, nothing beats a hot wAter rinse. A 1in , 5/8, 1/2 wrench, Phil, n a flat, and a brake adj tool the kind for drum brakes with a crescent wrench to remove the seat. Well actually I would practice on a few at a junk yard first just so you learn what not to do.
I pretty much figured out the choke is closed like normal. Then, when given gas, it blows open. It's DEFINITELY too much air not enough fuel. I tested it by leaving the choke the way it is, giving throttle, engine starts to bog down. Close set choke a bit, give it throttle, engine sounded great. So I need to adjusted the choke. Where do I go from here gents?
The chassis manual they are talking about . I bought one too. I found it on Amazon. For 36$. Both volumes. 1&2. They are majority at 80+$ . just in case you money was being an reason you don't wanna get the book
Alright so the way to make it not stall is to give it more gas. That's the key. If it starts to bog down I have to slam on the gas and subsequently burn out. This happens HORRIBLY during turns. Another thing I noticed. If I press all the way on the brake, the oil light comes on. If I make a turn, the oil light comes on. I'm guessing I need new brake fluid and power steering fluid. Other than that it was a pretty solid ride.
Ounce your warmed it should run with choke wide open, you still have an issue , take your can of carb cleaner and with the engine idle ing, air cleaner off , give it a lite quick squirt at the top of carb, if your idle raises from a quick squirt then u have a vacume leek, if it stumbles that's what it should do .
