General Category > Quadrajet Carb Talk and Tips
LOW budget engine not working well....HELP!
Mudsport96:
--- Quote from: jberenyi on August 03, 2021, 02:22:24 PM ---
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Are you saying you reused to old timimg chain and gears?
Cliff Ruggles:
One reply says they replaced it, another reply says they used it over again.
I'm confused here for sure. We're getting "spoon fed" information a little at a time and it's conflicting.
The most important information given is that the engine only makes 10" vacuum at 650-700rpm's, and that would be with "normal" timing in it. It should be nearly double to that reading.
The timing is advanced some and it's got low vacuum, something is fundamentally wrong someplace for sure.
Has anyone done a cranking compression test?.......
jberenyi:
--- Quote from: tayto on August 03, 2021, 03:20:55 PM ---it has been asked twice if timing set was replaced and if so what TYPE. single roller, double roller, link belt (oem), non-adjustable, adjustable, etc. probably would be a good idea to include if the cam was degreed/checked.
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I keep saying everything is bone stock except for bored cylinders .030 over and then honed. Everything else is OEM stock stock stock!
Mudsport96:
--- Quote from: jberenyi on August 03, 2021, 08:33:26 PM ---I keep saying everything is bone stock except for bored cylinders .030 over and then honed. Everything else is OEM stock stock stock!
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Ok i realize you are getting frustrated, but to the guys that build engines this doesnt make sense man.
You had heads machined correct? This is a change from the original engine, so there could be a problem here.
You reused the old cam... did you keep track of which lifters went in which holes? If not you will wipe the cam lobes fairly soon stop running the engine and buy a new cam and lifters. This could also be your problem.
Reused the old timing set... looks slack or not this is not a good plan. Was it a single keyway sprocket or multiple keyway?
Did you use the thick felpro style head gaskets or the very thin sheet metal gaskets? Thick ones will change compression which will dictate different base timing needed. .. and can lead to similar issues.
You stated that the carb ran fine before the engine was rebuilt. This leads me to believe it is not the carb but an engine issue
Some guys here are probably just unsure of where to go with all the old parts reusing. Ive done it myself out of several buckets of worn parts.... BUT never expected the engine to idle perfect, just run enough to move the vehicle around.
Mudsport96:
--- Quote from: jberenyi on August 02, 2021, 06:43:50 AM ---Fast forward, one month ago my friend let the oil get low and spun a bearing so we had the block cylinders honed and replaced the rings, crank, crank bearings and one connecting rod.
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Replaced the crank and one rod? Guys that are in the know are there more than one keyway? Pretty sure one is 2 degrees right of tdc and one is 10 degrees right. And the 86 and newer cranks are like 30 degrees. If this is the case and the new crank keyway doesnt match your balancer and timing cover your timing will LOOK right but be wrong.
Also if it is the original balancer the outer ring may have slipped in the process of removal and installation. So get a piston stop and find tdc with that.
Were the rod ends resized? If the crank was damaged enough to warrant replacement, one would think the large end of the rods would be damaged too.
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