hello i have a 1962 pontiac with rochester tri power that is flooding for third time .i have driven car for 5 years and it have total overhaul 3years ago. no problem after that untill now changed fuel pump and filter as the filter seams low (transparent) i did not realize that the fuel was going in engine flodding outer carbs. ken sweden
Those carbs like the fuel pressure to be around 3psi. Put a pressure gauge and regulator in line to adjust it. maybe your new fuel pump is puting out too much pressure or maybe your carburetors need rebuilding. Also check to see if your floats are set too high.
If the carbs are flooding, the needle valve in the carb isn't shutting off the fuel when it reaches the correct level in the bowl. It could be a float problem, a needle and seat problem or the fuel pressure could be too high for the needle valve to stop it. I would include that the level might not be adjusted properly but I assume it ran well at one point and this just started. Some carbs have floats made of foam and some of today's fuels can eat into those floats.
Just what do you mean by flooding? The end carbs on my '61 Bonneville like to overflow upon starting if the car sits too long - the needle and float stick, and gas runs out of the top of the carbs. I have to pull the carburetor tops off and fiddle with them, and then they're okay.
what i mean is engine is rough on idle and will not answer on little gas just drop dead,so you have to pump the gas pedal.when sut of gas is dripping down carb i notice this when i was finish for the day it is 9,40 in eavning here i will take lid of tomorrow and check for dirth and see why needle is not shuting fuel of when level is right.i will check pressure i been tingking of this before some pontiac with ac have a return on fuel it is on filter so it will lower pressure a little and keep petrol cool thanks for helping out ken
i had problems with floding carbs if they are emty from gas the flot was hanging i use electric pump and prv with prv with to high pressure it flod too My tri power works much better after i deside to floor the pedal alway at least one time every time i use the car /Stefan
is it a oldsmobile engine you have stefan? i like the colour you have on engine .i have the same on my cadillac ken
On the 66 I had, that was a common problem, About every two years. I got so good at changing the needles and seats that I could do it blind folded. Funny that was never the center carb, only the ends. They drip fuel at idle right?
My Son is pretty much running the same tripower setup you have, except on his 468 Olds, and it does like only about 3 pounds of fuel pressure. I think what happens to the end carbs is that the gas just sits in the bowls for long periods and unless you open up the trips occasionally some of the stuff they are putting in today's gasoline works on the needles and pumps. Since you are running on the center carb 99% of the time you are turning over the gas in that one but the gas in the end carbs will become stale, causing some plugging and deterioration. I have nothing scientific to back that up, but I also see it on the 2 x 4 setup I am running, the front carb will start gumming up unless I run it wide open once in a while, and then it runs good for a while after that. So I drive with my foot through the floorboard as often as I can. Don
You need to clean out that old gas in the outer carbs. I have been useing seafoan in my gas about every 3 or 4 tanks stuff works great
Yes, you don't want that to happen. Smell your dipstick..if it smells like gas at all, change your oil & filter right away. Hopefully, your flooding situation wasn't that bad.
you changed the fuel pump. When you did that the pressure increased on the needle valve/float. Bet if you reset the floats lower in the end carbs you won't have the problems. I have the same setup, big base Rochesters. I use a stock pump, no regulator, and have not had any problems. Less is better on 3x2. cooger--see avatar
GAs has additives in it and when they sit or dry out too often they leave deposits and a "varnish" like substance behind. This then binds to the metal surfaces and does not allow the needle valve to act correctly - they stick or don't move , get hung up or just down right choose to do their own thing and then let too much fuel in and you have flooding. Cleaning all the parts helps and sometimes it needs a darn hard scrub with the right cleaners and then there are times when there is too much damage and the needle valves still fail. Its a tough one on engines that are not used that much - if it was working everyday then the issue does not arrive - its a sign of a pampered engine
thanks for all tips i try to fulltrotlle every time i drive car but it seems that vinter storage and cold starts with only one carb is what happen .i took off fuel line on outer carbs and flush with carb cleaner true inlet right on needle when carbs was low on fuel. and it helped on rear carb but i did take off front as it was still dripping ken
You may also want to make sure the outer carbs butterflies are closing all the way at idle, having the butterflies cracked open a hair will cause them to flood at idle.
not always you can fix it with a hammer????? the ting is that where i hooked up the tv cable to the th700 was the problem.gaslinkage always have been little slack on brass axle and if engine idle 500rpm i dont mess with it but yesteday i found out that trottle axel on center carb was not in position .i got sidways when letting gas of and let engine passing air trugh gap on butterflyes and engine just stop. took carb of for at least 11time and hammerd on axle to get it tight on shaft.had a punch on other side of shaft so it will respond to force. when it was tight i put it on and idle at once. front carb still dripping no proroblem what so ever.i was looking on wrong place thanks for helping out
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