Can't get motor to fire... at all

[vetteman91]

I just had a similar situation. MY 383 had not run since '98. Replaced point dist with EI, had power to pos side of coil but could not get any spark. After fighting for some time I found out the tach inside car is shorted out and was killing the impulse from neg side of coil. Removed tach wire from coil (-) and it regained spark. Got it to start with dist loose and dialed it around until it idled on its own. I just started back at basics and hooked up only what was needed and figured it out on accident.

 

[yfdcap]

I would also try a fresh set of plugs. I know you said they are new but with all the trying to get it going they could be bad from to much fuel.

 

[440beep]

If its an auto tranny car, could it be a bad neutral safety switch?

 

[dvw]

What do we need to run? Compression, ring seal, valve seal, CORRECT valve timing. Rotate the motor until the #6 cylinder lifters are open the exact same height (roll the motor by hand slowly and use a straight edge). This is split overlap. At this point we are at TDC compression stroke#1. The distributor should be pointing at the #1 wire in the cap and the timing marks should be with-in 3-4 degrees of 0 on the balancer. Now we know the cam is lined up correctly, #1 is in the correct location on the cap. Wire the cap/plugs 18436572 counter clockwise. Next we need spark which you say is good. Our previous test proved out the correct ignition and valve timing. This can also be verified with a timing light while cranking. Now we need fuel, actually a burnable gasoline and air mixture. It does have fresh fuel and not E-85, correct. You didn't mention what type of ignition you have. If it's an electronic distributor it will have spark if the 2 feed wires are backward, but at the wrong time. The only other posibility is that some one installed a Hemi cam. Then the valve train is EIEIEIEI instead of EIIEEIIE.
Good Luck
Doug

 

[62 Dart Convertible]

If its an auto tranny car, could it be a bad neutral safety switch?

He says it's cranking over and has spark, so I'd say not.

The suspense though is killing me....

"Will it start? Is there a stuck valve? Is the dizzy 180 deg out? To find out, tune in for the next episode of "Mr.Joshua and the 383"

 

[Mr.Joshua]

Diagnosis confirmed. No compression.

#3 and #5 had less than 30lbs. Didn't even go further. Motor is getting yanked. Rats.

It was going to get pulled anyway to work on the engine compartment so it isn't a huge deal.

- - - Updated - - -

"Thanks" given all around. Appreciate all the advice. Now have to figure out my next move. Rebuild the 383, rebuild and stroke it, or buy a 440?

 

[Arkansas66]

I do hope you did pour some oil/trans fluid down the carb to oil up the rings.. a dry engine will not fire up or make compression and fire up, been there many times .

 

[Mr.Joshua]

I do hope you did pour some oil/trans fluid down the carb to oil up the rings.. a dry engine will not fire up or make compression and fire up, been there many times .

It was a dry test but not registering even 30psi is a bad sign. Re-tested the #3 cylinder after oiling it and that got me up to 70psi. #5 still didn't get over 30psi after oiling.

Never tried pouring oil in the carb. Usually have to do some jury-rigged contraption to squirt directly in the spark plug holes. Does the carb method work well? How much oil do you usually pour down it?

 

[eagleone1983]

Josh,

If it were me and I could do things over again I would have stroked out the 400 I have in my backyard instead of putting in a 383. Not saying the motor sucks but with a sure grip and 3:55s in the back my car has a hard time breaking loose, that or put lower gears in. I already asked my wife if I could do a stroker and she almost killed me.

 

[mopar12372]

even with 2 cylinders down it should run ,

 

[bee69]

pull the wire plug to the distributor stick a tap wire on black wire off distributor plug plug back in then steadly tap wire on valve cover or intake while some one cranks it over just had same problem with a 440

 

[bigmanjbmopar]

even with 2 cylinders down it should run ,

Agreed you should at least get a rough running motor with 2 cyc down. I see you said you rebuilt the 750? you have spark, air, what about the gas? try a different carb? fuel pump working? how are you pumping gas to the carb? just wondering if the pump rod is stripped?

 

[Mr.Joshua]

Agreed you should at least get a rough running motor with 2 cyc down. I see you said you rebuilt the 750? you have spark, air, what about the gas? try a different carb? fuel pump working? how are you pumping gas to the carb? just wondering if the pump rod is stripped?

Pulled the carb and it was getting fuel. Brand new fuel pump with a brand new fuel pump push rod. Pressure is fine. My uncle has another carb I can borrow if it does turn out the Holley isn't in working order for some reason. Went through it fairly thoroughly though and all looked well with the rebuild.

99% sure now that its poor compression that's killing me. I thought that when I initially primed the cylinders with a little MMO, that would be plenty to get her running. But thinking on it now, it was more than a week it sat since I primed them and got my carb squared away. I'm going to pull the motor either way but I think I'll give starting it another go this weekend with freshly oiled rings and see if I can get enough compression to start her up and get the oil pumping.

Arkansas66 recommended straight up pouring oil/trans flluid down the carb/intake. Anyone ever done this? Personally never have myself. Usually used a spray bottle or a spare hose and poured it directly in the spark plug hole that way. Pain in the rear though.

 

[dvw]

Stop, Why doesn't have compression? What type of cam? Loosen the rocker shaft bolts equally a few turns. Maybe the heads were milled or a sunk valve job. The pushrods could be bottomed holding the valves open. If this is the case it can be repaired in the car.Loosen and recheck compression.
Doug