Ok, my motor, i just put a cam in it, and intake. tried to start it up, nothing. put a different carb on, started, but that carb went bad. another carb, started right up, ran fine, but had to cut it off. went to start it up again and it started and revved to about 4000, then cut off. this time i had tied the chock open so i could break it in, and i didn't have the choke wired up. after that it wouldn't start, just pop pop then a 4ft fireball out the carb, EVERYTIME. so i'm pissed! all this cranking without it firing is going to RUIN MY CAM! note, the carb is an 86 qjet with electronic metering rods, and carb is not plugged in. any thoughts? ideas? suggestions? prayers? words that'll make me think the cam ain't gonna go flat. HELP PLEASE!!!!!
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
on a serious note. . . WTF!!!!! (HELP NEEDED ASAP!)
- Thread starter BowtieRed
- Start date
SF87K5
1/2 ton status
you sure the timing is right?
83ZZ502_Jimmy
1/2 ton status
Sounds like the distributor is 180 out. Anytime the engine is backfiring thru the carb, its timing.
John
John
no, remember it ran good, plus i've already checked for 180* out. timing could be off, but i thought i tightened the distributor down at around 4* advanced.
SF87K5
1/2 ton status
keep changing the timing a lil at a time till it will idel and you can get a timing light on it.
can't let it idle, i gotta break the cam in.
84_Chevy_K10
Banned
These guys are telling you exactly what I told you. Get the timing accurate enough for it to run, break the cam in, and you'll be able to let it idle and set the timing correctly.
smprider112
1/2 ton status
if im reading things right...U have a electronic carb that ISNT plugged in? that could VERY well be yer starting and running problem...but deffinently get it timed right too!! /forums/images/graemlins/thumb.gif
my thought too, but i don't understan why it ran good at first, then revved to about 4k the second time??? /forums/images/graemlins/confused.gif
backcountry
1/2 ton status
- Joined
- May 27, 2004
- Posts
- 916
- Reaction score
- 0
Are you sure your fuel pump is ok?
Timing is an easy fix. Remove your #1 spark plug and valve cover. Rotate your engine to get #1 piston at top dead center. Remove your distributor cap and make sure that the rotor is pointing to the #1 wire. If it is ok, this will be fine to get you engine running to break your cam in. This of course is assuming that everything else is ok.
Also: you can also experience a backfire if your plug wires are on wrong. Check your firing order just to be certain.
Anytime you change carbs; make sure to fill the float bowls up with fuel before trying to fire up your engine.
Good luck! /forums/images/graemlins/peace.gif
Timing is an easy fix. Remove your #1 spark plug and valve cover. Rotate your engine to get #1 piston at top dead center. Remove your distributor cap and make sure that the rotor is pointing to the #1 wire. If it is ok, this will be fine to get you engine running to break your cam in. This of course is assuming that everything else is ok.
Also: you can also experience a backfire if your plug wires are on wrong. Check your firing order just to be certain.
Anytime you change carbs; make sure to fill the float bowls up with fuel before trying to fire up your engine.
Good luck! /forums/images/graemlins/peace.gif
timing was fine, getting spark, plug wires in correct order. spark looks weak, bought new rotor button (already put on new cap)
one more thing that makes me think it's carb related- the only time i can get any firing out of the engine is if someone sprays carb cleaner or starting fluid in the carb. . . but honestly i don't know what's wrong at all. if all else fails i'm going to check the distributor gear for missing or chipped teeth, and maybe pull the wires and check resistance.
one more thing that makes me think it's carb related- the only time i can get any firing out of the engine is if someone sprays carb cleaner or starting fluid in the carb. . . but honestly i don't know what's wrong at all. if all else fails i'm going to check the distributor gear for missing or chipped teeth, and maybe pull the wires and check resistance.
k20
3/4 ton status
r u sure the motor is getting gas? I know i always ask u that, but everytime i think about it, i always come back to thinkin the fuel pump is crapped out, or something to that effect....
and i tell you everytime that my fuel pump works, i have a glass filter, i can SEE fuel going in.
Before i go work tomorrow, any other things i should check?
Before i go work tomorrow, any other things i should check?
beater_k20
Banned
potential vaccuum leaks would be my guess. we did a plenum gasket change on my buddy's 94 Firebird, and he left the plenum bolts loose, used the wrong TB gasket in the kit, and left the brake booster unplugged. it would "idle" but at 4000-4500.
also, the "electronic carb" was mentioned. your truck DOES NOT have this unless its a Cali truck. i believe what you're referring to as an electronic carb is the carb with one connector going to it (other than the choke), this connector operates a dual capacity accelerator pump. it will give it more gas if it is not plugged in, but it will still run fine.
the running with carb cleaner says its running very lean as it is, so that throws out the accelerator pump idea, its going to be either fuel delivery or vac leak somewhere.
also, the "electronic carb" was mentioned. your truck DOES NOT have this unless its a Cali truck. i believe what you're referring to as an electronic carb is the carb with one connector going to it (other than the choke), this connector operates a dual capacity accelerator pump. it will give it more gas if it is not plugged in, but it will still run fine.
the running with carb cleaner says its running very lean as it is, so that throws out the accelerator pump idea, its going to be either fuel delivery or vac leak somewhere.
84_Chevy_K10
Banned
He's used about 4 different carburators now. It's like I always tell you guys, everyone thinks the carb is messed up but it's always ignition. /forums/images/graemlins/histerical.gif
NOT ignition. EVERY cylinder is getting fire. Timing has been set at everything from -4 to +10, played with distributor all day, new cap, new rotor button. tested spark at every plug. i thought maybe a few cylinders weren't firing because i could here it hitting but would not run as soon as i let off the starter. then wouldn't do anything later on. i guess it's time to pull the valve covers and see if i'm still getting any lift out of the cam or check for bed pushrods or broken/incorrectly set rockers.
THIS IS RIDICULOUS. if you know what you're doing and live near winston-salem, give me a holler, and come help me!
THIS IS RIDICULOUS. if you know what you're doing and live near winston-salem, give me a holler, and come help me!
Whats the saying? 90% of carburetor problems, aren't?
maybe collasped lifters?????????
if i had money i'd get a roller valvtrain and new heads and be done with it.
ANY IDEAS, no matter how farfetched are appreciated.
ANY IDEAS, no matter how farfetched are appreciated.
anyone? thanks.
