CarburetorsCarb discussion and questions. Upgrading a Third Gen carburetor, swapping TBI to carburetor, or TPI to carburetor? Need LG4 or H.O. info? Post it here.
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Had to replace the intake manifold gasket on my car. After getting it off I got injured at work and couldnt get back to it for 3 weeks. Anywho I just got it running again with a brand new Quadrajet (btw this is an 87 camaro 305) and i do have a couple probs I cant seem to figure out.
Out of gear idle about 1k with occasional spurts at 1400. In gear Idle is about 600 (automatic tranny) BUT at speeds over 30 the idle wants to hover around 1500-1700. I can take my foot off the gas and maintain 49 mph in overdrive. Once u hit 30 u can feel the differance of the idle settling down to where it should be.
My secondaries are not opening at all. The bar moves (from the vaccuum canister diaphragm thing) a little bit then stops.
I should also point out that im not ENTIRELY sure the vacuum hoses are correctly in position. I tried to remember what I could but I dont think I got em right. If anyone could post pics of the carb vacuum and where they go i'd appreciate it. Actual pics not a hood diagrahm. That thing is greek to me lol.
Thanx for any help in advance
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this post has a clear diagram of vacuum lines/parts routing used before 1987. there are some differences in routing and maybe the canister. Anyway, it's close so should help with identifying parts/routing to be better understand the '87-specific emissions sticker:
Sorry for the delay. Got sick this week and just getting around to getting outta bed. Took the old girl out for a spin today and couldnt get the darn thing to stay below 2500 rpm. After digging around, the plunger on the throttle assembly (gold round with electrical hookup) was stuck. FINALLY got it to settle down. Ran like a dog though whenever I tried ot get the secondary barrels to open but I think I found that problem.
Thanx a TON for the pics at the end just before this post. That helps out a LOT!
Unfortunately my dang egr controller brok e a plastic piece and napa spent 30 minutes trying to find one. Out of stock at all the locations in thier list grrr. So had to plug the old girl off. Thankfully i dont have smog checks here where i live lol.
No cant wait for daylight so I can hook those hoses up right! I can already see where I made a booboo or 2.
Thanx once again for the ton of help u've given me.
If you look at the carb body on the drivers side, just above the carb base plate behind the throttle lever that the cable attaches to, you'll see a little screw pointing forward with a spring around it. Thats your idle speed adjustment screw. It may just be set too high.
Once the engine is warm, have you made sure the choke is opening? If not, the fast idle may be staying on as well if the choke is not opening.
As for the secondaries not opening - the secondaries are mechanical, they will be yanked open when you open the throttle all the way. But there is a little catch mechanism that seems to lock the secondaries mostly closed when the choke is still on. That may be what you are having a problem with? It should go away when the choke opens. If you are talking about the air valves on the top of the carb, they shouldn't open unless the engine is under a load when driving - they aren't supposed to open when just revving in N or P.
Yea the idle is initially fine. But then on the way to work she'd start to idle higher.
UPDATE:
I did have a couple hoses backwards and thanks to Scooter500 pics I got them correct. Also had a vacuum hose on the rear of the carb that was worn enough that it would start sucking air when things got warm. Replaced that thing believe you me!. Got everything done right and she's purring like a kitten. Havent test drove it yet cause running low on fuel and out here in the boonies gas is running $4.52 at the only gas station in town lol. Gonna wait till I hit work tomorrow for the test drive and gas is $4.20 at safeway with meh discount hehe.
Thanx for letting me know about the secondaries. I got wired wide open right now but ill disconnect that and see what happen on the way to work tomorrow.
THANX a ton for the help everyone. Just trying to keep this 305 going till Feb when Ill FINALLY have the money for my ZZ4 motor.
Now if anyone knows about 460 in a F250 lemme know lol. She runs great but consuming a LOT of oil and dunno why. No smoke and no leaks so im a bit stumped.
Now if anyone knows about 460 in a F250 lemme know lol. She runs great but consuming a LOT of oil and dunno why. No smoke and no leaks so im a bit stumped.
Only two ways oil can get out - either its being burned, or you have a leak. The F*rd 460 design is HEAVILY influenced by the BBC (hell, even the valve covers interchange lol), so I would imagine they would have alot of the same issues over time. I would start by checking for leaks - mainly the front and rear main/crank seals, and the valve covers. Those are the most common leak areas with any of the old pushrod V8s.
Yea I already been down that road. Engine is clean as a whistle. I bought it last year and had the engine steam cleaned and checking today all around its still really clean. However I did notice my coolant tank is looking a tad dark and its a bit brownish on the walls so i think I found my leak. Did read somewhere that the radiator develops a leak tween the oil cooler and the water due to some o rings that fail internally. Gonna take it down to work and pressure test the system. If that fails, we got some dye for oil and the light and ill know for sure its getting in the water which im pretty sure anyways lol.
