8N. runs smoothly & then sputters, backfires and stops

Doug Blakey

New User
My Ford 8N. has been running well until just recently. After about 10 minutes of smooth running it starts spluttering, may backfire a few times and then stops. Pulling out the choke may prolong the rough running but the tractor won't be able to move & certainly can't take a load.
I have checked the fuel flow to the carburettor, have taken the carburettor apart and cleaned it, cleaned the air filter to no avail. I'm wondering if this is a fuel delivery problem (maybe the filter screen in the gas tank is clogged?) or an electrical system problem.
Does anyone have any suggestions of what I should do next?
 
(quoted from post at 09:27:35 05/22/20) Take the fuel cap off and see it it continues? Maybe vent is plugged.

Thank you for your suggestion. I did try that but it did not solve the problem. After sitting put and idling at a fairly full throttle, it sputtered and backfired after about 7 minutes. I pulled out the choke which in a few seconds returned the engine to smooth running but again, after a few minutes it did sputter and backfired again. The choke approach worked again. I drove it up a gentle incline for a few minutes and then it all happened again. Pulling out the choke this time just caused it to lurch and stall, lurch and stall.
Any further ideas?
 
(quoted from post at 09:27:35 05/22/20) Take the fuel cap off and see it it continues? Maybe vent is plugged.

Thank you for your suggestion. I did try that but it did not solve the problem. After sitting put and idling at a fairly full throttle, it sputtered and backfired after about 7 minutes. I pulled out the choke which in a few seconds returned the engine to smooth running but again, after a few minutes it did sputter and backfired again. The choke approach worked again. I drove it up a gentle incline for a few minutes and then it all happened again. Pulling out the choke this time just caused it to lurch and stall, lurch and stall.
Any further ideas?
 
Hi Doug, welcome to the forum. The forum just below this one is for the N series tractors like yours. Plenty of knowledgeable folks on there. The first thing they will tell you is. 1. Remove the plug at the bottom of the carburetor and see if you can fill a pint jar in 2 minutes. If so, you don't have a fuel problem. 2. As soon as it stops running have an adjustable spark tester set at 1/4 inch (or take an old spark plug, gaped at 1/4") and check for spark at one of the plugs. The fact that pulling the choke and getting a temporary positive response can be a symptom of weak spark. But do not go out and start throwing parts at it. That can get expensive and if you happen to buy a new defective part, it compounds the problem. If you do post this on the N forum, be sure to tell us if your 8n is a front mount or angle mount distributor. It makes a difference in diagnosing a spark problem.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top