OK, the saga of getting my 462 lined out continues. After a short detour through ball joint hell and still residing in overheatig land, I'm trying to address my Q-jet stumble and eliminate it as a source of overheating. My carb numbers are 7041540 MF 0831. What is the best kit to buy to rebuild it? I haven't had one apart in about 10 years but I think it will all come back to me pretty quickly. First, I know my top cover is warped and I've been running two gaskets for more than 10 years. Secondaries are DA rods on an F hanger. Primaries may be 74 with unknown rods. I have a set of 70 jets and 45B primary rods I took out of a junk yard carb. Anyone have a good Q-Jet baseline specs for a Buick 462, forged pistons, maybe 9-9.5 compression, Edelbrock Performer and aluminum unported heads, TA212 cam, M/T Repro headers with 3" exhaust? Specifically, what primary jet sizes and rods would deliver crisp throttle response and moderate performance? Some days I think the old motor with a new pan gasket and front seal would have been less trouble... NAH!
Get your parts from Cliff Ruggles. Www.cliffshighperformance.com. Call him and he will set you up. Use the thick air horn gasket to seal good. 74 or 75 jets and .043 primary rods. And replace the power piston spring. Idle tubes to .036 DA rods are good. Replace the secondary air valve cam and tension spring. You should have enough idle bypass air if the carb is original. May need to open up the lower main air bleeds and down channel restriction. I can email you my recipe for my BBB 800 cfm performance builds.
For the love of Christ, no Chinese parts here!! Call Cliff x2. Not sure if he is a fan of DA secondary rods - may want to ask him.
Cool. I will give him a buzz Monday. If you don't mind, the recipe would be great. This thing has been rebuilt about 4 times since I've owned it. Has the good pump and had a big needle and seat at one time. We replaced the primary shaft bushings about 15 years ago due to leakage. Had the TV nub welded on about 5 years ago. Probably time for a freshening, get the gunk off and check the well plugs again. It is ugly as sin. Someone left it in the cleaner too long and ate all the plating off it. My email address is same as my name at Gmail.
Email sent. As long as the previous rebuilds haven't severely altered the original condition of the carb, that is a great carb to build from. Even better if you can get the APT screw in base plate loose.
I don't think mine has an APT since it is a 71. Thanks for the info. Should help. I emailed Cliff and will call him in the morning since I've disassembled the carb and know the internals. The fuel filter was probably plugged, definitely lots of black sediment in it. Probably should consider dropping the tank to find my build sheet and flush it while I'm at it. The primary jets are 75 and the rods are what looks like 44E but I suspect they are really 44B just not rolled the "B" on around. The "4" is mostly missing the vertical bar on it also. Some of the internal screws were loose and I suspect that has contributed to my woes. Plenty of yellowish residue in the carb bowl and on the jets. Not sure I can clean this up with just spray cans of carb cleaner. Will see if they have a dip of the stuff at one of the stores locally. The saga continues!
What's the best thing to seal the primary and second jet wells? The primaries were sealed with a black epoxy and it fell off. The secondaries were sealed with some orangish rubberized stuff that also fell right off. Does JB Weld still fit the bill? I'm sure this was MORE of my carb problems.
Tha APT screw is in the base plate in center front. Covered with a plate. Most are very hard to remove. I recommend Marine Tex epoxy to seal the wells. I have not seen anything else that will hold. Most of the well plugs don't leak. The early ones almost all leaked so they got the bad reputation. I seal all of them I build with Marine Tex anyway though. No need to take the chance. There are some later ones that do show signs of leaking.
Ah, that actuates the little thin strip in the base plate. I was thinking of the later models with the bubble on the front passenger side. Cliff is sending me jets and rods and a piston spring to make it all work. If I could get the plug out of the APT screw, does it need to be resealed or can it remain accessible? How's it adjust? Mine was full of gas in every cavity and orifice. Places I don't think gas was supposed to be were full. The secondary well plugs had gas in the base plate. Cheap insurance on a 44 year old carb. Nobody carries Marine Tex locally that I can find. Would the JB Weld marine be a good substitute? I've read where some folks make a mold around the well plugs with masking tape and pour it in.
Cliff has APT screws to replace the existing in base plate. The cover is easy to get off and can be left off. The original screw is very hard to remove, but worth it if you can get it out. Lots of heat and penetrating oil. I have not used anything for years except the Marine Tex. guess you could try the other stuff. You don't need to get it thick. There is a small space between baseplate and well plugs so if you get it too thick you will have a sealing issue.
I was thinking just using the tape to get a level fill since the stuff tends to ooze a bit. I can always file it down and the front ones are hard to get a good amount on.
I got the cap off the APT but can't get it to budge. Left it it soaking in penetrating oil and no movement. Back together with new parts and set float, high flow needle and seat but can't test until I get my gas tank delivered. Slowly but surely.
OK, gas coming out the accelerator pump hole around the rod. I'm guessing the float is too high or... float don't float. Anything else I should look at before I tear into it?
Float is probably to high. Set to 9/32". Also make sure needle is in the seat good. Don't use the clip to hold it to float.
Those are very hard to get loose, and many times, they won't come loose. Use heat and penetrating oil.
Well, got it apart and gas was everywhere in it. Needle and seat looks good but the spring that holds the primary jets got mangled some how. Jets were still in place though. Float was set to more like 5/16" upon examination and floats in gas. Before I disassembled it, I hit the air horn screws one time with a screw driver. All went down easily another 1/8-1/4 turn except for the drivers side near the breather stud, which appears to be stripped. Still didn't help. I'm using the same electric fuel pump I was using before so I don't think it should be flooding the carb, overpowering the needle and seat. I do not know what the pressure is but it is a Carter that is 30 years old, similar to this and never ran a regulator on it before. http://www.jegs.com/i/Carter/180/P4389/10002/-1?parentProductId=1145238 Maybe it is time to cut my losses and get another carb without a stripped hole, all the plating worn off making it ugly as sin and a warped air horn. Got anything good similar to a 7041540 ready to run? Cliff sent me 74 jets and 42B rods in the kit he put together. Only condition is I will have to swap my base plate onto it since I have a TV cable. I may call John Osborne since he's only an hour or so up the road.
You might want to get a pressure gauge and see what that electric pump is pushing for pressure. It sounds like it may have gummed up or something and is putting out too much pressure and blowing through the needle/seat. If you end up needing a built body and air horn, to put your base on, I could do that for you too.
I got some longer screws that will hopefully find some bite deeper into the body. As for the fuel pump, I'll just shut it off. Not required to run and while it is helpful to prime after replacing the gas tank, it can go any time. I'll see if I can scrounge up a low pressure gauge and check it. I do have it running through a stock stage 1 fuel pump with a working bypass line.
Tapped out the holes and made sure I had enough depth for the two problem children right by the secondary rods, cut down some 1.5" machine screws in the proper thread to be 1/4" longer than the stripped one. Replaced the mangled primary rod retaining spring and crossed my fingers as I reassembled it all. To test and prime it, I let the electric pump run. With the motor off, I can hear it gurgle and could tell the bowl was filling but it never leaked this time and the pump went from high speed to a the "UUhh..UUhh" that it does when it reaches the proper pressure. So, I can only hope the stripped screw and mangled primary rod retaining spring somehow conspired to keep the float down and allowed fuel to go every where. It did fire but it was late and I didn't want to open the garage and annoy the neighbors. If it closes this chapter, back to the overheating issue. Good cool morning should help.
I hope it does work out. Another thing I forgot to mention before, is the float pin. It need to be open enough that the air horn is against it an holds it down. Sometimes you have to spread them open a little. If it isn't held down by air horn, the float can lift and won't hold needle in the seat.
