My Buick has been sitting in my garage for the past two seasons and I am trying to get her back on the road. She started right up a couple of weekends ago and I took her out for a short drive. Then last Thursday night, I took my wife out to dinner in it and she started right up after dinner then drove over to my Daughter's to see our Grandkids. Everything was fine until we went to leave after about a half hour. My Buick cranked fine but would not start. I took the air cleaner off and cranked it again and saw fuel literally spewing out the carb like a geyser. I finally had her towed home. Today I took a closer look at things and fuel was still spewing out the vent shown in the photo. She instantly flooded again and would not start. What would cause this and more importantly, what do I need to do to make it stop? It's been since high school since I've had a Quadrajet apart and I do not remember what what this vents to. Hey, I'm getting old! 67 GS400, stock engine and carb. Help! Thanks,
Flooding like that usually means your float is stuck down and/or your needle/seat is stuck open. Nitrophyl floats over time can soak up gas and get heavier...i.e. they sink in the fuel and don't regulate the level in the fuel bowl correctly. Take the top off of the carburetor, and change your float. Check the needle/seat as well, and replace if corroded or worn. Debris on the needle can also prevent it from seating and cutting off the fuel flow like it should do. If your car has been sitting with old gas in the carb for an extended time, there could also be varnish build-up which causes the moving parts inside the carb to stick. Get a can of carb cleaner (B12 chemtool works best), and blast out anything which has gunk build-up...especially your needle/seat if they don't look too worn out. If it ran well, then suddenly just started flooding, then the needle/seat probably has debris jammed in there keeping it from closing. If the problem persists, check your fuel filter and change if clogged or damaged. Long before I joined this forum and learned more about Q-Jets, I used to seal my inlet with teflon tape which is famous for causing problems similar to what you're experiencing. I've had my share of other issues, but I am learning as I go.
What is the carb number? the tag looks to be silver which would be the later 248.. If it is an earlier 67 carb with the plunger needle seat or conversion upgrade, could be that the fuel stop plug popped out... Happened on my 240 model and the fuel pumped out as you described... Or as stated above could cause it as well. Time to freshen it up and prep it for today's alcohol fuel anyways...
I don't know what the carb number is. I have crawled all over my carb and I cannot find a carb number. I know where it supposed to be, but there's nothing there. And there's no tags either. Maybe it's a dealer replacement? Where's the best place to get a rebuild kit from? I am sure I can get one from any one of the big box stores, but will they be the most complete? Thanks,
The number is on the circular aluminum tag on the driver's side of the carb body, near the accelerator pump arm. If it is correct for a Buick 400, I think it should be 7027146(early 67) or 7027244 (late 67). Your carb looks to be mostly original, and has the switch-pitch linkage intact. Sometimes, the tag falls out of that circular depression which holds it, it is staked in place. The choke flap looks different than mine...it has the screws for the flap on the ends rather than closer to the middles of the bores. The external vent in the front also appears to be blocked off, and the cover is missing. Maybe it is a re-manufactured unit. Don't go to big box stores for carb kits...Gessler's has very good kits & parts for Q-Jets: http://www.quadrajetparts.com
Thanks for that, I'll give them a call tonight. I knew my carb needed work, but that was a project down the road. My next project was to rebuild the distributor, I picked up a reman unit from Autozone last week. It was a pretty good deal, $40 and no core charge. I was going to pull the points and recurve the distributor. Once I had the ignition behind me I was going to tackle the carb. How priorities can quickly change.
The carburetor has no plating left on any of the parts. Not surprised there is not tag on it. Most likely it's a commercially remanufactured unit from a parts store. Could be miss-matched componets as well. The bowl vent is capped off, vent linkage not used, probably has a "generic" calibration as well. Those carburetors are always a MESS. Might be a good one to send out to someone who knows what they are doing, to get it back in good working order.....FWIW......Cliff
I took a closer look at the carb yesterday, you can see where the tag was staked in place and it fell out along the way. I plan on sending the carb out for rebuild, it definately needs it. Thanks,
