1951 Plymouth stall issue when stopping

[DonaldSmith]

Quoting kencombs, "Kids used to do the ignition off, coast, back on to create that BANG back in the day."

 

I blew out the muffler of our 58 Chevy Brookwood station wagon that way.  The driveway was uphill, right past my parents' bedroom.  No way of coasting by.     

[hep2jive]

Coil ground was loose!!!!!! What about the muffler swelling? It "looks" the same... what's that about? 

[kencombs]

4 hours ago, Sniper said:

 

That's a misfire, tend to make the mufflers swell up.

 

 

That is a back fire, as in it went back out the way it came.

Yeah, I know, but a lot (most?) use the word to mean any big bang.

[hep2jive]

28 minutes ago, kencombs said:

Yeah, I know, but a lot (most?) use the word to mean any big bang.

Huh?!

[Plymouthy Adams]

24 minutes ago, hep2jive said:

Huh?!

N O I S E   

[joecoozie]

2 hours ago, hep2jive said:

Coil ground was loose!!!!!! What about the muffler swelling? It "looks" the same... what's that about? 

Muffler swelling happens when the car backfires through the exhaust and the pressure from the backfire will sometimes "swell" the muffler or it can also blow the muffler open at the seams or any weak spot in the metal

[DonaldSmith]

BOOM 

 

 

2015, timing off by a plug or two.  Ears buzzed for a half hour or so. 

[Plymouthy Adams]

that picture easily defines the big bang....

[Sam Buchanan]

Redneck exhaust cutout....

[Kilgore47]

2 hours ago, DonaldSmith said:

 

Yep - did that on the 25 dollar 54 ford in 1967.  Pumped the gas a few too many times with the ignition off.  Then it was off to the junk yard to find a muffler that was in better shape.

[hep2jive]

Yikes the pop I heard wasn't that bad!!! ?

[greg g]

Is it fixed yet?  After driving and it stalls, open the hood with engine  off.  Is there raw fuel at the base of the carb?  If not, I would think it's electrical.  Check all the wires and connections to and from from the ignition switch. As mentioned there is a thin flexible wire inside the distributor, this wire is flexing with every chang in vacuum. It can look good but be broken under the insulation or if the insulation is frayed or missing this can cause problems with grounding to the distributor body.  Also check the insulation on the terminal where the wire from the coil connects

 

Have you done a vacuum test?  You might have a vacuum leak which causes an extrem lean mix that causes the stall.

 

If you don't know how to do a vacuum test, go to secondchance garage.com. There is an excellent  how to there.  You will be checking intake manifold vacuum, not carb vacuum.

 

One more thought,  is your choke fully opened at idle at normal operating temp?  Check your dipstick, does your oil smell like it has gas in?

Edited May 15, 2023 by greg g

[greg g]

OK one more.  Modern points sets are mostly junk.  Several people have had problems with insufficient spring tension leaving the points to hang open.  This usually presents as a high rpm misfire, but it's worth checking.  You should be able to feel resistance when you try to open the points with a small

screwdriver. 

Hopefully you are doing this with the distributor out of the car on the bench or in a vice.  This will assure everything  is squared away and tight.