heres the deal my 302 ford runs like it has a stuck valve.pops back in the carb, no power, not back firing just pops .did a compression test tonight.best was 135 worst was 120,not to bad for a motor that has been setting sence 1980.the exuast pipe on the driver side is wet smells like gas ,not oil.2 of the plugs on the driver side were damp.(gas smell) checked both plugs they are firing fine the plugs on the pass side looked good.all parts are new plugs wires cap rotor coilthe only parts that are used is the hei dist and the control box or what ever you call it.i do geta little lifter noise from the drivers side when you wing it up but not loud.car has NO power and is slugish on the revs.timing is set at 8degrees btc i put a kit in the carb ,when i got the car running .any ideas???????
the firing order was tricky it has the same order as the 351.i tried to run it with the order that was on the intake ,no good wouldnt the burnt exuast valve shown up on the compression test?
id agree the compression check would have showed a bad vaulve. check your firing order bump your timing up to about 10 or 12 then adjust your floats it sounds like its in the carb good luck
if it is stuck closed it may read OK on a comp test. How about pulling the valve cover and hand turning to see. I'm really just guessing and trying to help. But I must bow to stangzilla's knowledge.
Not to sound like an ass, but have you driven this car/truck before? What is the tranny that you have? Before you dropped the motor into it's new home did you change the timing chain? Any fluid in the tranny? Just trying to help out not trying to be an ass
already ran the motor with the covers off ,all the rockers are moving up and down as they should,the rods arent overly lose or tight.ive run the firing order a few times im pretty damn sure its right.but what would the carb have to do with the popping?what gets me is that the motor is so flat.no responce,when its just setting there its ok but when you put it under a load it pops.
the motor was installed in the mid 70s my dad drove it until 1980 it set in my grandmas back yard until a few months ago ,it ran very good when it was parked.i drive it around now but it runs like crap .trans is a 3 speed stick,all fluids have been changed.fuel pump all the normal shit you have to do to a car that has been setting,
It sounds like a gas problem, my 302 did the same thing on the way back from a show. The tank had a ton of crap in it that passed through passed the filters and messed up my carb. I flushed the tank and sealed it and rebuilt my carb. I still get the pop that it sound like you are getting but after it warms up it goes away.
well if your floats are to low it'll starve your motor and it'll pop you might have a flat spot on your cam too there are alot of things that can be wrong does it smoke black at all? could also be to rich and your air fuel mix might be wrong
Then I'll go with Stang. You got a Holley on there? Check for ruptured accel pump, funky lifter? Still grasping at straws, armchair diagnosis.
Possibly the timing chain jumped a tooth, or lost some if its a plastic gear. Line all you markers up to #1 and see what you get.
it is hard to say from fort worth you might see if a buddy has a carb you can borrow for a day and see if that helps any. that would be less painful than the alternitives got to start somewhere might as well start at the top
I'm sure that you are aware of this but just in case, the cylinders are numbered 1-4 on the drivers side and 5-8 on the passenger side. As opposed to the chevy set-up that goes back and forth from one side to the other. This does get a little confusing when setting the firing order. That's what it sounds like to me. Good luck! Don.
If the motor is a 302 installed in the 70's, then it isn't likely to use the 351 firing order. The 5.0 HO engines were the only 302s to use the 351 firing order, and Ford didn't produce those until the eighties. While it is possible to use a 351 cam in a 302, I doubt that's the case here. Keep in mind that small block Fords fire counter-clockwise on the distributor, the opposite of a Chevy. I'd double-check that while verifying that the distributor isn't in backwards, and use the firing order on the intake. Here's a pic:
What Zonk said. You could have a collapsed lifter on an exhaust valve causing the popping through the intake - I doubt it's carb/fuel related if you've been through the carb & are confident it's correct, but could be wrong. I seriously doubt your timing chain jumped a tooth - a sheared distributor drive gear roll-pin is much more likely than a timing chain jumping, but that's no common either.
When my 302 jumped time, it would not run at all. We did manage to mess up the firing order, and it gave exactly the symptoms indicated...... These deals are aggravating, but not usually too expensive; good luck.
im trying a freinds carb this weekend,hoping that will get it going .i would think it was just one exhuast valve sticking or even 1 lifter that it would run better than it does .thanks for all your help.
I am betting the timing chain and gear are worn and have jumped a cog causing the cam to be in a retarded position. This will act as a backfire because of too much gas and the engine will have no normal accelleration. Take the distributor cap off, put a braker bar on the crankshaft bolt and move the crank back and forth. If you can get about an 1/8 to 1/4 turn on the crank without the rotor turning you have a wore out timing set.
Grab another duraspark module from the wreckers, they are cheap and can be the cause of alot of problems. Normally on a small block ford it won't skip a tooth...it will take them all off. Double check the coil too, had the same problem with my 351, it exploded and made crazy problems. Something else to check anyways, good luck.
If it were me I'd remove the valve covers, turn the engine by hand, and figure out FOR SURE what firing order the cam wants to see. Again, NO 302 as old as the one you describe used the 351 firing order stock from the factory. Either someone swapped a 351 cam in there years ago after the fact, or you need to use the 302 firing order. Ain't nothin' else gonna matter if you've got the firing order wrong. Having said that, it's possible that you might have two problems--perhaps the timing chain DID jump a cog, and that's what made the 302 firing order seem wrong?
If you want the first line/cheapest fix, go buy a new dist cap and rotor. I had a Chevy S10 with Vortec V6 that came to me via death of a family member. Well, it always would run like crap on rainy days and the few days after. We figured it had to be water getting in the fuel. After many different fixes, new gas cap, new fuel filter, pulling and draining the tank twice, tracing fuel lines, new PVC valve, Air filter, .... I pulled the dist cap. It looked fine from the outside, but under it, it was slightly corroded. Changed cap, rotor, and the spark plug wires, and it ran GREAT! Hope you get it solved cheaply. Let us know what fixes it.
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