Trying to upload a movie ....give me a chance The car is hard to start Requires a lot of pumping Choke works because I do get a fast idle Once I get the movie uploaded maybe you can confirm if my accelerator pump needs work I don't get a stream of fuel more like bubbles and a small squirt
I had a similar issue on a newly professionaly rebuilt carb. The accel pump was binding 1/2 way and not giving a full shot. Brand new modern accel pump, I had to change it. pull the throttle and watch the accel pump and see if the arm goes all the way down. It could be a lot of things..........
OK here's the video... The motor was slightly warm here, about 2 minutes. Long enough to start, idle, back out of the driveway and back it into the garage. Ive seen what a good squirt of gas looks like on other carbs, and this carb is not doing it. Yet when driving, there's no issues. Runs really well, takes off quick, burnouts are no problem (so Ive been told uzzled and there's no hesitation. [video=youtube;ZMZFNeZ3J34]http://www.youtube.com/watch?v=ZMZFNeZ3J34[/video]
The pumps around here state there's no more than 10% blend.. so .. yes. Carb was rebuilt by a board member, and running has not changed.. but starting requires alot of pumping.
ethanol is hard on the rubber on the accelerator pump. i cant tell that that is your problem by the video though. just a thought. there is a pump you can get from cliff ruggles or greg gessler that is friendly with ethanol...
Ethanol is really bad for the pump cup. Get the replacement from Gessler. Better yet, if you can get the whole accel. pump....
Ethanol breaks down the cup seal in the accelerator pump. If you are going to replace the accelerator pump, go with the Edelbrock 1982 accelerator pump. It really wakes up the carb, a little extra fuel with each pump. http://www.amazon.com/Edelbrock-1982-Accelerator-Pump/dp/B00062YC38/ref=sr_1_1?ie=UTF8&qid=1362764927&sr=8-1&keywords=edelbrock+1982
My Rochester 4bbl on my 72 skylark 350 also binds half way and was rebuilt by a member. Will this accel pump work for mine? I get a slight hesitation half way and sometimes I have to mash it to "unstick" the halfway point, especially when sitting for a week or more on a cold start. Mark
Here's a pic from the shop showing what we do with the currently available pump cups that are showing up from the suppliers.....we replace them with our own pump cup, the dark blue ones in the left rear of the photo. Despite the pump cups being blue or black, and Viton, they are swelling up in contact with this new fuel and sticking in the pump bore. The seal we use has been tested in E-85 with zero failures to date......Cliff
So Cliff; When my Skylark sits for say a week, and I go to start it - I push the accelerator down and half way it has a hard stop. I have to kick it to break it free and get a full pedal to the floor. Is this the cup sticking to the bore? I ended up buying a replacement pump (stem and all) from Napa and it still had the same issue. If this is the case, would it also lead to the slight hesitation under load about mid throttle? Mark
NAPA pumps may have a "blue" seal on them, but all blue seals are NOT created equal. The over the counter seals will swell up some in time and stick in the pump bore. We found this out as we buy accl pumps form the same source that supplies Echlin, and other over the counter kits for q-jets. Also interesting that just about every time we order pumps, they come with a different seal on them. Some are dark blue/thick soft seals, most often lighter blue/soft, and most recently thick/soft black seals. ALL of them failed testing when we soaked them in currently available pump fuel. The seal we use is dark blue, and a very hard material. Even after a year in ethanol fuel it still has the exact same dimension it did before soaking it. I've been over and over this deal for the past 3 years, just couldn't get the suppliers to get this deal right. The answer for us was to remove the seals and install our own seal, which is impervious to ethanol, or any current additives in modern fuel blends.....Cliff
The one I got from Napa did indeed have the royal blue cup. So mine is swelling and sticking when it sits? And how would I then go about getting a cup / pump assembly from you? Mark
Greg has an informative article on his site. Note where he states the 'long skirt' design cup sometimes folds over and sticks. He suggests using the 'garter spring' cup as a replacement. http://quadrajetparts.com/quadrajet-accelerator-pumps-t-11.html
Good info on pumps. We only use the later style pumps with the upgraded seal and garter spring, and they come with new springs and a retainer. Be aware that many pumps being sold come with the wrong spring on them, that will coil bind when the pump fully compresses. We see a LOT of them installed in carbs sent here. The short Edelbrock high performance pump is POS, and to be avoided. It will often show up with a return spring that has the same tension as the duration spring, rendering the pump next to useless. It also has the long lip "soft" seal on it, and will fail in this new fuel......Cliff
