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  #1  
Old 04-17-2000, 07:25 PM
340dave 340dave is offline
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I checked the historical posts but couldnt find an answer for this problem so...recently pulled 340 and tranny to install rebuilt tranny. Pulled carb and dist to avoid damaging, then reinstalled engine after regapping plugs (to .050 as per Crane Hi-6 instructions) and installing new wires. Tried to start, engine fires only with a lot of gas pedal then backfires thru carb and dies. Can't keep it running.
I checked;
1. Timing, bought damper around to TDC , pulled #1 plug and could see piston up in hole, roated dist base so that dist rotor at #1 plug. turned dist back and forth to see if timing changes helped, not really!
2. Vacuum, Holley 3310 attached vacuum advance to port on pass. side of carb, plugged brakes into manifold vac. no other holes open.
3. Plug wires...all attached in correct firing order.
This engine ran great prior to this exercise in patience (or lack there of). What am I overlooking? Man I want to get on the road!!

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dave
340 Rallye Challenger
340-S Barracuda
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  #2  
Old 04-17-2000, 07:37 PM
Duster440 Duster440 is offline
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this happened when i bought a 360 a year ago for my duster. What was wrong with my engine was that the distributor was installed backwards, needed to be completely switched 180 degree. After i did that , twisted the key and it came to life, talk about happy. A buddy of mine almost had me convinced to buy a new cam, but luckily i checked that first. Not sure if thats whats wrong with your car , but if the distributor was removed , mabey it is in backwards.
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  #3  
Old 04-17-2000, 08:23 PM
340dave 340dave is offline
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I thought that might be it too, I swapped it around and it immediately backfired! maybe ill try it again


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dave
340 Rallye Challenger
340-S Barracuda
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  #4  
Old 04-17-2000, 08:46 PM
Stan Cameron Stan Cameron is offline
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Just a thought.

When you installed new plug wires did you check rotation direction of dist. clock wise - counter clock wise. My son changed plug wires on car said he checked fireing order and it was correct. He wired for clock wise not counter clock wise.

Also check timing marks on damper (the outer ring can sometimes slip).

Hope this helps

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69 RR 426 4bbl 727 9.78 @ 138 best so far.
79 Lil Red Express.
96 2500 Ram 5.9
99 Durango 5.9
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  #5  
Old 04-18-2000, 01:52 AM
383 383 is offline
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Your having the same problem I had awhile ago. I changed my plugs, and wires, and I couldn't get the thing to start back. Man, I was pissed, checked everything from the carb to the chrome box. Turns out I had the wires one post out of rotation. Pull your #1 plug and rotor cap off, keep the rotor on. Using a rubber covered pliers jump the relay on the firewall(or use a remote start switch)pull your finger over #1 hole and wait for the compression to build. watch your rotor, and you'll know if your out of order real quick. Make sure you pull your coil wire..so it won't start...Once you know the dist is correct back track the system to the coil..make sure your getting a good spark...
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  #6  
Old 04-18-2000, 04:38 AM
DAVE JONES DAVE JONES is offline
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I think that there is alot of good advise here and after recently rebuilding my dist from top to bottom and recurving it I've pretty much made all the mistakes possible within the last month. The problem you described is the same as I had several times due to numerous acts of ignorance and unfortunently stupidness on my part. The only thing I'm going to do here is put what the others said in order of what I would do if i were you and give a brief detail. The only other thing that I would advise you to do that is real quick is see if there is excessive play in the rotor back and forth when it is installed in the block. if there is, there could be an additional problem that needs to be looked at. while you got your head in there I would also check the gap in your points or your mag pickup and adjust if necessary.
1...pull #1 plug and turn engine over to make sure that when the piston hits tdc it really is on the compression stroke. By placing your finger over the hole you will definantly feel the air forcing it out. then line op the damper at 0 on the timing mark. this should be TDC on the the correct stroke as long as the damper didnt slip.
2...reinstall the dist. Usually the rotor is pointing toward the number 1 plug or toward the front of the engine. It doesnt have to but thats the way most people have it.
3...remove the wires from the cap. place the cap on the dist loose. Rotate the base of the dist till the rotor lines up with a terminal on the cap as best as you can eye it in. You can keep on lifting the cap on and off till it looks right. once it looks ok then place a pc of tape on the side of the cap where the rotor is pointing to. You now marked number 1. AT this point i would snug down the dist holddown so it wont easily move.
4....clamp cap and reinstall wires. Double check rotation ..should be CW. Unfasten dist cap and make sure it still lines up with the number 1 terminal of the cap and wire.
5....Before final clamping of dist, rotate the dist very slightly CCW...apx 5 deg. This will help preset your advance and probably make starting easier.
6....If it backfires during starting then rotate the dist CCW again slightly. Many times the dist is not advanced enough from eyeballing it in and this WILL cause backfireing. Its not the only cause but its real common.
.....good luck..keep us posted.....DAVE

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  #7  
Old 04-18-2000, 12:47 PM
340dave 340dave is offline
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Lots of help, thanks...still having the same problem
Checked the wiring to my Hi-6 last night, it is wired correctly and is getting the correct signal from the coil, based on the LED signal Im getting from it. I spun the the rotor 180 again just to check, got a huge backfire, put it back the way it was, engine wanted to crank then when I tried to feather it...died. I marked my rotor cap for #1, and replaced them in order so I wouldnt get them out of order. SB plugs are clockwise, opposite BB
What is excessive play in the rotor? I have some movement here, but its no different then it was before I pulled the engine and it ran great! How can I check for a stuck valve? Could it be stuck just from sitting over the winter? the valve springs, cam and retainers are all new last summer and ran with no problems.
383 are you saying to pull the plug and plug wire, then crank her over and see if there is a spark out of the dist cap when it comes around on the comprssion stroke?
thanks


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dave
340 Rallye Challenger
340-S Barracuda

[This message has been edited by 340dave (edited April 18, 2000).]
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  #8  
Old 04-18-2000, 03:14 PM
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440Ramcharger 440Ramcharger is offline
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Was your intermediate shaft removed and reinstalled improperly? Check it next time that you distributor is out.
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  #9  
Old 04-18-2000, 05:59 PM
383 383 is offline
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If you have luck like me, it's always the overlooked stuff that F's with you. I would try to keep your trouble shooting simple, trial and error right down the line.
1st Have you disassembled your dist at all since it ran last? If so take a trip to auto zone and order a rebuilt one...It'a about $50 bucks, use it , get the car running,clean it up and get a refund... HA HA
2nd regap all your plugs to .035 just to get it running
3rd if you have anything but a stock cam your timing marks gonna be off...so don't trust them
4th confirm firing order CW 18436572
5th everybody sets up the dist different ways,mines 180 off so the vac advance is out of the way
6th pull your 1 spark plug turn motor over and find your #1 terminal, mark it on the dist...turn your motor over a few more times and watch your rotor just the confirm your mark...move your dist around to line up on that mark...you want the rotor spin to #1 and the end off compression stroke(air pressure on finger to be timed close)
7th put everything back together and try to fire it...it should start..try some starting fluid in the carb....if it runs better with fluid it's the carb messing with you...if it still won't start it's MSD, and I don't know anything about those

don't trouble shoot with old plugs get new ones...get a spark tester from Auto Zone $5 it lights when the coil zaps the wires..Get somebody to turn the motor over for you while you test each wire installed on the spark plugs installed in the engine that way you can rule those out also.

one more question did you remove the middle shaft off the cams teeth and out of the oil pump...if so you gotta find TDC.. and start from scratch on the dist timing

This is everything I did when I messed up on my engine..but I kept the Auto Zone dist..ran to good with it.

Rob
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  #10  
Old 04-19-2000, 03:40 PM
340dave 340dave is offline
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Well you wont believe it, but it wasnt a timing problem at all. I talked to a fellow racer at work, and he mentioned that fuel additives will gum up the works if they sit in the fuel for a while. I run 104+ Octane boost and premium and the car had sat for a couple of months while I built the tranny, so I pulled the front bowl and swapped my 72s for some 74s I had, when I started it back up it ran much better, though it still wont hold an idle so Im going to get some carb cleaner and spray the inside good tonight. Thanks for all your help, I hope this solution helps someone else out there !

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dave
340 Rallye Challenger
340-S Barracuda
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