<lunatic>

I have a olds 350 in my 77 regal and I am having a problem with idle,I changed the carb because that was the problem before,at first I thought I had bad gas because it idles rough now its starving for gas ,I had to tape the choke almost closed to make it home and changed the carb but its the same, also there is blow-by that I never saw before,I changed the module,cap,rotor,plugs but it sounds like its starving for gas,if I close the choke alittle it runs smooth,also turning the idle screw up didn't work. Is the choke suppose to be all the way open when it warms up?also I turn the distributer alttle and it breaks the tires loose then stalls HELP ME PLEASE

Oldsguy

First you need to put your timing back where it was. If you can remember the approximate location the distributor was in do that. You can't set timing while the choke circuit is active, you engine has to be at idle/warm condition to set timing. After that, I believe your problem would be the choke circuit. It's possible that both carbs had a mal-adjusted choke. When the engine is cold you should slowly pull the linkage all the way back (or push the accelerator pedal down). It is better to move the linkage from the engine bay, observe the top plates on the front (four barrel carb) or just the top plate (two barrel carb). It/they should close all the way with a small crack left between the plate and the throttle bore of the carb. If the plate/plates don't do this then the initial choke setting is off. Usually the choke on a Rochester is activated by a round bi-metal spring located in a round housing on the passenger side. There will be three or four retainer screws holding a black colored plate. Loosen, don't remove these screws, this will enable the plate to rotate, there is a slot in the middle of it, use a large flat blade screwdriver to twist it in the direction marked "rich". Be careful, if it doesn't move easily you might break ths slot. In some instances you have to totally remove the screws to see if it is jammed up with carbon junk, but don't do that unless you absolutely have to, it's not to easy to re-assemble. Anyway, you should see the choke plate move when you rotate that black colored plate. But you have to have the acclerator linkage pulled back all the way too. If you can reach it from the passenger side and do it with your off hand. If not you will need help. Adjust the choke so there is just a crack of air space as I described earlier. Then tighten the screws. This is all done on a cold engine that hasn't been started. If this doesn't help you may need more adjustments to other items like the choke pull-off device. This lets the choke plate open a little temporarily when you "hammer" the gas pedal during driving conitions when the choke cirucit is still active and the engine isn't warmed up yet. But that would be later. Just set your choke first and see if that helps. I hope so. Good luck.

lunatic

thank you, its hard to think when I'm mad [img]smile.gif[/img] I will try that before I warm it up also I took off the cap and rotor(before Christmas)and noticed it was alittle
rusty(on the advance springs only) so I put some grease on it,do you think the grease is making it stick? thanks for your replies Junior

lunatic

I did all the adjustments like you said and it ran fine at first then I couldn't get the idle below 1100 in park but decided to drive it but after I put it in gear and put my foot on the power brake the pedal was hard and it died after that so I started it and it ran like crap and would not idle I forgot till today that with the other carb when it was cold the power brakes didn't seem to have vacuum until it ran for a minute so this problem seems to have gotten worse with time maybe I have a vacuum leak somewhere? when it warms up the choke is all the way open but if it runs for awile it seems to lose power .thank you for any feedback Junior

jdorour

<blockquote>quote:</font><hr>Originally posted by &lt;lunatic&gt;:
I have a olds 350 in my 77 regal and I am having a problem with idle,I changed the carb because that was the problem before,at first I thought I had bad gas because it idles rough now its starving for gas ,I had to tape the choke almost closed to make it home and changed the carb but its the same, also there is blow-by that I never saw before,I changed the module,cap,rotor,plugs but it sounds like its starving for gas,if I close the choke alittle it runs smooth,also turning the idle screw up didn't work. Is the choke suppose to be all the way open when it warms up?also I turn the distributer alttle and it breaks the tires loose then stalls HELP ME PLEASE <hr></blockquote>


Won’t idle, brake pedal effort is high, up shift is harsh
It sounds like you have a major vacuum leak.
Have you checked for a leak? Check the hoses, EGR Valve and PCV Valve. Make sure you have all of the hoses hooked up. If you have a replacement carburetor there may have been more ports on the carb than you needed. Make sure you have any un needed ports plugged. Check the base plate gasket for leaks.

Oldsguy

jdorour has a good point. With the brake pedal effort problem that indicates vaccum leaks. It may even be the power brake accumulator/booster. If you have a vaccum gauge you could check it that way. You should have 15 to 18 pounds at a good idle of about 850 rpm. A way some people localize vaccum leaks, after of course a good visual for obvious un-connected ports etc, is to use starting fluid, it is a lot safer than using gasoline or carb cleaner because it's flash point is much higher. Buy a can of that stuff and spray in suspected places like the carb baseplate like jdorour mentioned, intake manifold sealing surfaces to the head near the ports, distributor vaccum advance pot, any vaccum pots on the carb, and places where there are T's and sensors hooked to vaccum lines. You will notice a jump in idle speed where there is a leak. I suggest you start your car and let it warm up right in the driveway, don't drive it, after the engine is warm just goose the accelerator linkage to dis-engage the choke circuit, if it does the idle should drop. If the engine will still idle on it's own then do the spray trick. Your idle should be smooth and even. If it isn't you probably have a vaccum leak. Also, the grease on the mechanical advance springs probably didn't hurt although you can buy a light grease made for that purpose, it's no biggie. Just don't use too much, it only takes a little. The condition of the tower contacts are more important to determine distributor cap "health". There should be no/little corrosion on them, white if they are aluminum and reddish if they are copper. You have to take this whole thing one step at a time though. Make sure you don't have a vaccum leak first. Good luck.

lunatic

ok this morning I put a plug in the vacuum for the power booster and it seemed to run fine but I couldn't drive it without brakes so I put the vacuum back on the power booster with a knew filter which it didn't have before and a check valve(how do you check that?)and drove it to the gas station holding the idle up with the pedal,put gas then stuck my foot in it broke the tires loose then it sound like it lost power then it would'nt idle will a power booster from a 68 firebird work? it looks the same,thanks to everyone for your help
Junior

lunatic

today I put the carb back on with a new gasket and plugged the vacuum for the power booster,took the stuck thermostat out for awile ,but it wouldn't warm up but the choke worked fine but only opened up alittle (it use to open up all the way)so after running for awile it stayed cold according to the gauge but the motor seemed warm then I pushed down on the gas and it sounded like a "baahg" and would not idle right ,any ideas anyone I also used starting flud to check for leaks but couldn't find any

lunatic

ok! I changed the carb,fuel pump,hoses removed gas tank changed hose and I am ready to put gas and start,has anyone had a problem with"starving for gas" on a olds 350? it runs fine with the choke closed but dies when it opens

Oldsguy

I'm sorry I missed your last few posts. I have been checking here on a regular basis, just missed them I guess. I'm not sure how to solve your problem but I do know that you need to replace your thermostat. Your car will take forever to warm up in the winter without it and that just throws the choke circuit off too. You need to fix that. I still think a vaccum gauge might help you find your problem. get one and put it in a vaccum orifice on the manifold, you should have a good 15 to 18 inches of vacccum easy when the engine is warm, then, when you goose the throttle it should drop to about 5 inches temporarily. If you don't have that, you know you have a vaccum leak someplace. You said a few posts back that it ran better when you plugged off the booster. Do you mean the place on the back of the carb? It is larger size that most vaccum lines. If so, that is the right one. Try that again, let the engine warm up all the way, then drive down the street a ways and back, don't go too fast and stay in a residential area, you should be able to stop the car without the booster it would just be harder, unless you are really small or have weak legs it should work. don't step on it just tool around real easy like, if the car runs fine that way you have an indication that the booster may be leaking. I don't know what car would be a good donor for one. After you get that problem fixed and you can drive around easy with the new booster (if you needed one) then try driving harder and opening the secondaries (you DO have a quadrjet, right?). If you still have a problem it may be in your timing or secondary circuit.

Thermostat first
Vaccum leak second
carb/timing problem third

Good luck.

lunatic

I will try those ideas,thanks for your time
JuniorJuniors World of Kustoms