Backfires

[Ric0126]

My '51 8N is back firing through the carb and wiil not start?

 

[Bob]

Cracked or wet distributor cap?

Messed up firing order?

Stuck valve?

Blown headgasket?

 

[Bruce (VA)]

6v or 12v?

Start by checking the firing order: 1-2-4-3, CCW.

Then, check the points. Gap is .025. Make sure they aren't burned/pitted.

Make sure the distributor is bolted down tight & that the timing bolt isn't loose.

Post back w/ results or more questions.
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[Dell (WA)]

Ric......what else happened that you ain't sharing with us??? I flunked mind reading, just ask my ex-wife of 32yrs. We don't charge for extra words. Based upon yer short vague description; time to do the dreaded compression test for stuck valves. The only reason for backfiring thru the carb is stuck intake valve which a compression test will reveal. ......Dell

 

[Ric0126]

Sorry, I have the same problem according to my wife about details. This is the 8N daddy left me. It has been setting up since his passing four yars ago. I have rebuilt the carb and cleaned the fuel tank. Replaced the plugs but not the cap and points. I am getting fire to all of the plugs and there is gas flow to the carb. It ran briefly before I did anything but only on starting fluid since the tank and carb were varnished up. I am assuming cylinder order from back to front as #1 being near the dash and #4 being near the front?

 

[Bob]

Cylinder numbering is FRONT to back.

 

[Ric0126]

Ok cool on the cylinder numbers... I'll double check but I have not changed the wires or distrbutor so hopefully I have not messed that up..

 

[Anonymous-0]

Whenever a gas engine backfires thru the carb the timing is off.I have proven this to many pigheaded men. good luck

 

[Den N Ms]

Ric0126,Check your compression on all 4 cylinders.After setting 4 years chances are its a stuck intake valve.If it doesn't have compression on one or more.Remove side covers and look for a intake valve stuck open. If so post back for info on how to free it up.

 

[Bob]

George, I agree with you 100%.

(Except when a sticky or burned valve or blown headgasket is involved!)

 

[Bruce (VA)]

I had an N backfiring thru the carb because the plug wires were shorted in the conduit. I had another back fire thru the carb because the points had closed.

There is more than one reason for it to backfire thru the carb; timing is but one of them.
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