01-23-2004, 06:49 AM
I have been noticing a gas smell as my(350 ci) 77sprint sit in the closed garage. The wife is complaining about it. I pull the air cleaner and found the top of the Rochester carb wet with gas. mainly by what I think is the accelorator pump rod coming out the top of the carb. Is a full rebuild in order, or can I just put a new seal on the rod, or is there probably a hole in the diaphram. Should I be able to find just the seal/diaphram, and appropriate gaskets? The engine runs fine and I am definately not a wiz at carbs, so I am hesitant to try a full rebuild. Are carb kits hard to find for older Rochester carbs? Oh, yeah, there is no tag attached to the carb. any way of telling exactly which carb this is?
01-23-2004, 09:53 AM
You won't find just the few seals that you are looking for. You'll need to buy a rebuild kit. Most Q-jet rebuild kits are around $20. Since you'll have to remove the air horn to get at the accelerator pump, and you'll have the entire rebuild kit, you might as well do a complete rebuild.
On the drivers side of the carb there will be a number stamped vertically. Write it down and go to your local NAPA or any good auto parts store. Most rebuild kits are readily available.
Go your local book store (Barnes & Noble type) and pick up a copy of Doug Roe's book about Rochester carbs. After reading it you'll know how to do a minor rebuild on your Q-jet.
01-23-2004, 05:47 PM
I guess I'll have to do that, though I sure do hate it because the thing runs so nice. But, a leak is a leak and likely dangerous. Thanks ernie
hot 78 El Camino
01-23-2004, 06:04 PM
I thought that I would mention to you that you don't need to purchase the book. If you go to someplace like CarQuest majority of the carb kits have the instructions to replace that one. As he said write down those numbers. If it is the original carb than it won't be to hard to figure out which one it is. Rebuilding them are really easy though and very painless. Have fun rebuilding it though
02-10-2004, 09:35 AM
If you plan on rebuilding the carb you might want to check a set of bolts inside there... cant remember which ones but the guys at the auto store will know. The bolts are famous for leaking on rochesters and you'll need to put some thread sealer on them. Check with the pros.
02-10-2004, 10:07 AM
Remove the Carb. Flip it over look dead into the Intake see if you notice a stain in the center of the pleninum. On the bottom of the Q-Jets (dead Center) there are two small jet housings that protrude down some. Very noticeable items. These are the front jets to the carb. This housing cracks over time. When it does it causes fuel to leak past them from the Carb's reservoir into the intake. Over night the cab will leak down so that a Single Pump of the accelerator pedal, generally sets the choke and primes the intake, will no longer start the engine. You will have to turn the engine over several times to refill the fuel reservoir before it will start.
This is symptoms of that leak. If that is the case you don't need to rebuild the carb. Just buy some epoxy, clean that area on the bottom well, mix the epoxy fill up the cavity with epoxy. Let it set over night. Put it back together the next day. From then on it will once again start with one pump, if the choke is set properly, and no more fuel smells.
Its a thought.
02-10-2004, 02:22 PM
Doing want Pete said is important but while you have it off you might as well put a kit in it. It is not hard to rebuild.
02-10-2004, 05:07 PM
be sure to buy a float with that kit otherwise you propably won't stop the leak. From your discription it sounds like the float is starting to get saturated.
02-10-2004, 05:40 PM
In order to seal all four casting plugs properly you need to remove the throttle body (lower 1/3 of the Q-jet). There are four places to epoxy. If you're planning to do this you might as well do a complete rebuild.
02-11-2004, 06:09 PM
thanks for the backup guys.. couldnt remember what those darned things were...