8N refuses to start all of a sudden

[Simple Farmer]

My 8N, that I have had for 60 years, will not start. I had parked it for a while, not having any trouble, and then I charged the battery. When I tried to start it, the engine would spin real fast. Like there was no compression. When I could get a cylinder to fire, it seemed to only be firing on one or two cylinders and it could not remain running longer than about 20-30 seconds. It seems like the timing is off. Is it possible for the engine to jump a tooth on the gear and begin this problem? Can one valve be sticking? I don't know, never had this happen before. How should I proceed? Thanks.

 

[Lynn Patrick]

Welcome LF! My first guess would be a little corrosion on the points. I had the same thing happen on my 541 recently & a little shining up of the points solved it.

 

[soaked]

Hi Simple Farmer,
Agree with low compression comment. Can hear rpms increase to a very fast rpm.
If no compression tester, take all the spark plugs out, and shoot in some PB blaster, and take the two valve covers off, and spray PB on the valve stems.
Run the starter a moment or two. Thinking a couple valves are sticking open.

 

[Ed S.]

Very easy to check for spark at the plugs, so do that first, but I agree with @soaked that, from your description, this sounds like possible stuck valves.

 

[Powered By IH]

My 8N, that I have had for 60 years, will not start. I had parked it for a while, not having any trouble, and then I charged the battery. When I tried to start it, the engine would spin real fast. Like there was no compression. When I could get a cylinder to fire, it seemed to only be firing on one or two cylinders and it could not remain running longer than about 20-30 seconds. It seems like the timing is off. Is it possible for the engine to jump a tooth on the gear and begin this problem? Can one valve be sticking? I don't know, never had this happen before. How should I proceed? Thanks.

Did you by chance convert your tractor to 12 volt?

 

[Duner Wi]

If the last time you ran it awhile ago it had old E10 gas in it at that time I would be thinking sticking valves.

 

[Jim.ME]

How long is: "I had parked it for a while"?

 

[Eman85]

Back to basics, spark test and fuel flow followed by compression test if the other tests are good. Now we're also assuming the fuel in the tractor is clean and fresh. And no unless some really crazy thing happened it didn't jump timing. But a human fiddling or a rodent playing could have moved or broken something.

 

[TJ64]

How long is: "I had parked it for a while"?

Around here that is 2-3 days.. .only because of rain. I need another one, cuz I can't afford to have it down to fix things, lol.

 

[used red MN]

If the points don’t fix it, sounds like it has crud/dirt/debris/varnish blocking the main carb jet. Clean the carb.

 

[Simple Farmer]

Welcome LF! My first guess would be a little corrosion on the points. I had the same thing happen on my 541 recently & a little shining up of the points solved it.

Well, it’s not that. I don’t have points. I have replaced them with the magnetic contact and it works great. I’m kind of worried about the sound. It doesn’t sound like I have any compression and I think that is related to the starting problem.

 

[Simple Farmer]

If the last time you ran it awhile ago it had old E10 gas in it at that time I would be thinking sticking valves.

Could be. The gas is not old, but the tractor is. Do you know how to check for sticking valves?

 

[Simple Farmer]

How long is: "I had parked it for a while"?

Probably a couple of months. I would come back to start it every once in a while.

 

[Simple Farmer]

Back to basics, spark test and fuel flow followed by compression test if the other tests are good. Now we're also assuming the fuel in the tractor is clean and fresh. And no unless some really crazy thing happened it didn't jump timing. But a human fiddling or a rodent playing could have moved or broken something.

I will get to work.

 

[Simple Farmer]

If the points don’t fix it, sounds like it has crud/dirt/debris/varnish blocking the main carb jet. Clean the carb.

Carburetor is not that old, but I could clean it, I suppose.

 

[Duner Wi]

Could be. The gas is not old, but the tractor is. Do you know how to check for sticking valves?

I would do a compression test. I have been down down this road so I know what no compression on some cylinders sounds like.

 

[used red MN]

Carburetor is not that old, but I could clean it, I suppose.

Sorry for lack of methodology, should probably go with what do the spark plugs look like first??

 

[Simple Farmer]

Sorry for lack of methodology, should probably go with what do the spark plugs look like first??

Spark plugs are clean. They looked carbon fouled, so I cleaned them up and reset the gap. The carbon fouled look may have been from the starting problem.

 

[Lynn Patrick]

I see nothing about spark. We "Long Timers" remember the quote "90% carb problems are electrical." Do you have spark, & what color & strength?

 

[Ed S.]

Is it still “spinning real fast” as originally stated?

Check compression and report back. I think that may be a critical clue.