Didn't Make It Home From Carlisle

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domdart

domdart

FABO Gold Member
FABO Gold Member
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Location
Johnstown, PA
I have a 2 1/2 hour drive home from Carlisle. On the way home my 72 D100 stalled going down hill on the turnpike. I just put it in N and started the 318 back up. An hour later it happened again going down hill on route 56. This time I pulled off the road because it wouldn't fire up while rolling. After about the third try it started and stayed running so I tried to make it home, about 20 more miles. Ten minutes later while going down the the Johnstown bypass it stalled again. This time it fired up while rolling and after a few seconds it backfired and shut off. The backfire sounded like a gunshot, very loud and violent. I pulled off the road. It would start but it would make a clanking noise. This noise didn't speed up when I would accelerate the engine. I put it in gear hoping I could limp down the road to a safer spot. When I put it in D it would go forward clanking then die after a few seconds. I put it in R to see if the tranny was working and it would limp backwards. There was no noticeable damage or leaks from under the truck or under the hood. I had it towed to a local garage. I am going to check it out tomorrow. What would cause such a loud and violent backfire? Did this violent backfire cause some damage? Anyone here ever experience anything like this? What do you guys think? Thanks FABO.

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I looked at this truck yesterday and thought how cool and clean it was. Beautiful truck.
 
If it is the timing set ( Likely on an original LA engine) you can istall one of the V-6 chain tensioners with the new timing set. I have done that on all of my LA rebuilds.
Sorry I missed your truck at the show it sure is a nice example. Good luck!
 
I expect the ignition cut out briefly, then ignited residual fuel in the exhaust. How does the muffler look?
 
Back in 86, I had put a 440 in a 71 B'cuda. The electric choke wire melted to the intake once and blew both mufflers open with a grenade of a backfire. Car died. Picked the wire up off the intake and started it up and drove on.
 
oh wait; the engine is on the way out, the trans has as good as blown up, and the rear end is next. l have a complete drop-in powertrain, so gimmee that old girl cheap, and I will put a few more years on the chassis.
lol
oh, wait; you're in PA, that's a deal breaker, shipping would be killer.
lol
oh, wait; I am of course kidding.
My guess is fuel percolation, or a failing fuel pump. and the clanking could be the muffler dragging on the driveshaft.
Nice truck, no joke

Check your fuel line jumpers. If any on the Suction side have gear clamps, those need to be doubled up, and the screwheads offset 180 degrees.
 
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domdart said:
I have a 2 1/2 hour drive home from Carlisle. On the way home my 72 D100 stalled going down hill on the turnpike. I just put it in N and started the 318 back up. An hour later it happened again going down hill on route 56. This time I pulled off the road because it wouldn't fire up while rolling. After about the third try it started and stayed running so I tried to make it home, about 20 more miles. Ten minutes later while going down the the Johnstown bypass it stalled again. This time it fired up while rolling and after a few seconds it backfired and shut off. The backfire sounded like a gunshot, very loud and violent. I pulled off the road. It would start but it would make a clanking noise. This noise didn't speed up when I would accelerate the engine. I put it in gear hoping I could limp down the road to a safer spot. When I put it in D it would go forward clanking then die after a few seconds. I put it in R to see if the tranny was working and it would limp backwards. There was no noticeable damage or leaks from under the truck or under the hood. I had it towed to a local garage. I am going to check it out tomorrow. What would cause such a loud and violent backfire? Did this violent backfire cause some damage? Anyone here ever experience anything like this? What do you guys think? Thanks FABO.

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Sounds like a bad points condensor, but isn't that thing electronic?
 
Yes a serious enough backfire can destroy an engine. Break pistons, bend connecting rods and even break crankshafts. That would be extreme damage, but it's certainly possible. Maybe it just blew a muffler up.
 
Killer6 said:
Sounds like a bad points condensor, but isn't that thing electronic?
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The original owner was a Dodge dealer in VA. He got this 72 D100 in November of 71. It is points. I am having it towed home tomorrow from the garage a mile away so I can start to work on it. I think there is some serious damage because of the clanking noise. The noise does not seem to match the engine RPM's though. The engine starts right up.
 
domdart said:
The original owner was a Dodge dealer in VA. He got this 72 D100 in November of 71. It is points. I am having it towed home tomorrow from the garage a mile away so I can start to work on it. I think there is some serious damage because of the clanking noise. The noise does not seem to match the engine RPM's though. The engine starts right up.
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The 'clanking' might be random detonation, also caused by a failing/failed condensor, hopefully the chain/sprocket hasn't failed....money's on condensor....
 
Don't forget extreme backfires can also bend pushrods.
 
I’ll come out there and tow it for you for free…….all the way back to California. Beautiful truck.
 
I cranked #1 cylinder to TDC and the rotor is pointing at the firewall. Shouldn't it be pointing to the #1 cylinder?

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Are you on the compression stroke? When at the top of the compression stroke, it should be pointing to the plug wire going to that particular cylinder.
 
domdart said:
I cranked #1 cylinder to TDC and the rotor is pointing at the firewall. Shouldn't it be pointing to the #1 cylinder?

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180 off, turn it another 180. Points may be worn and loosing their gap. I’d also check those red wires going to the coil. The wires may be frayed.
 
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old65-4spd said:
Are you on the compression stroke? When at the top of the compression stroke, it should be pointing to the plug wire going to that particular cylinder.
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The piston is all the way up in cylinder #1 and the line on the balancer is pointing at the zero.
 
Beautiful truck! Sorry I missed it. I'm betting on a plastic gear. If that's #1 exhaust stroke, it may be close though. Remember, it's a four stroke.
 
could be pointing at #6 if at TDC as well.

Pointing at #6 you are OK. Any other cylinder, not so much.

Nice truck, bummer about the situation.
 
crackedback said:
could be pointing at #6 if at TDC as well.

Pointing at #6 you are OK. Any other cylinder, not so much.

Nice truck, bummer about the situation.
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Sure looks like it’s aligned with #6. I was also goingto say check the ballast resistor. In looking at the rotor it looks hammered and burn’t.
 
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