Backfiring and gear changing

[kd1975]

Hi all,

 

We've rebuilt the 218 in my 54 Cranbrook. It was going fine but in the last day it has started backfiring and then stalling - the fuel pump is new so I don't think that's the issue. Any ideas on what might be causing this or where I should start looking?

 

Also we replaced the clutch at the same time. The rear main seal had been leaking for god knows how long and causing the clutch to slip - but it found the gears easy enough. Since replacing the clutch assembly getting the car into gear has been an absolute nightmare. Getting into first is not a problem but then trying to get into second is near on impossible, and same from second to third.

 

My mate helped with the car - he basically did it all and I paid him - so I don't want to go back to him and say he's stuffed anything up.

 

Any help would be greatly appreciated.

 

Thanks

Edited November 16, 2019 by kd1975

[Sam Buchanan]

Two items to check on the shifting problem:

 

1) Clutch adjustment

 

2) Shift rod adjustment

 

These could have been disturbed or changed in the course of the clutch repair. If the clutch isn't disengaging fully or the shift rods aren't traveling fully there will be difficulties shifting. Make sure both are in spec per the service manual.

Edited November 16, 2019 by Sam Buchanan

[vintage6t]

In terms of the sudden backfiring/stalling I'd first check the condenser. Even if you might have just replaced it the quality of new ones are poor.  

[keithb7]

Backfiring noise heard at carb and intake manifold? Or heard out the tail pipe? Possibly an explosion in the exhaust system?

[plymjim]

 Backfiring: Check the timing. maybe your distributor is loose. If you rebuilt your engine 

perhaps you didn't get the hold down plate tight.

  Shifting: Check for 1" of free play in the pedal.  Little adjustments

are to be expected after a clutch install.

  Best of luck.

[1951plymouth]

Agree w above 100%.  Backfiring in exhaust....Also would add that I have experienced when (as) the points wear out my car starts to backfire on deceleration.   I do run my engine a few degrees advanced as compared to stock fyi.  As far as the linkage I would look to see if the linkage rods are hitting each other as you shift. It's common in 49 to 52 plymouth s, which is where my experience lies.  Sometimes the cotter pins are the culprit.   

 

Lastly popping out of gear, it's possible and very destructive that your trans input shaft is not in perfect alignment .  This can happen when the trans mounting face or flange is not  in alignment with the bell housing and crankshaft.   Basically the input shaft and main shaft would not be in alignment .  There are some Chrysler Master Tech videos on this issue in YouTube circa 1948 to 1952.....excellent source of info for those of you not familiar .  Good luck 

[Sniper]

When words are all you have it pays to use them properly.

 

A backfire goes out the carb not the tail pipe.  A misfire or afterfire goes out the exhaust.  Two different issues with two different symptoms and two different solutions.

 

https://en.wikipedia.org/wiki/Back-fire

 

Years ago I had an afterfire issue on my 64 300, it was caused by a plug wire that came off the plug and the unburned fuel charge was being ignited in the exhaust causing a flame to shoot out one tail pipe and making a loud pop, almost like a gunshot.  I was waiting on a friend to finish checking out of the base pass and decal office when I first heard it.  From inside the car is sounded like a pftt. The gate guards were looking around for the gunfire, the office was right next to the main entrance.  The friend  was walking around the back of the car when it popped and he jumped.  That's how I found out what that sound was.  The link provided gives you some direction as to where to look depending on what it is you actually have.

[lepic56]

About the clutch ,, This could help ,