Engine won't start!!

[antoniojgraves]

I have a Briggs and Stratton 5 hp engine that won't start. It use to start until I replaced the starter clutch. I replaced the spark plug and sprayed starter fluid into the carb but still won't start. It has spark to the spark plug but can't seem to reach the problem. PLEASE HELP!!!!!!!!

 

[B man]

clean the carb.

 

[devino246]

clean the carb.

He said it wouldnt start on starter fluid, that rules out the carb

Are you using the correct plug and is it gaped correctly?

 

[Doc Sprocket]

Let me get this straight- It started and ran UNTIL you replaced the starter clutch?

 

[kendelrk]

does it sometimes backfire or rip out of your hands? you have to remember the starter clutch holds the flywheel down, so it has to be deathly tight, if its wasnt tight enough it might have sheared the key

 

[devino246]

does it sometimes backfire or rip out of your hands? you have to remember the starter clutch holds the flywheel down, so it has to be deathly tight, if its wasnt tight enough it might have sheared the key

Umm, no it doesnt...

Do you see a bolt?

 

[kendelrk]

on a briggs 5 hp, the back of the starter clutch holds the flywheel onto the crankshaft, to loose and it could shear a flywheel key theres a whole in the bottom to tighten onto the crankshaft to hold the flywheel down

 

[Doc Sprocket]

The same is true on my 8hp Briggs. I was trying to fix a mysterious no spark one day, and had to take the flywheel off a few times in a row. In my haste, I didn't tighten the clutch down properly, and did frag the key.

 

[antoniojgraves]

That is correct it use to start and run until I replaced the starter clutch. I have put gas in the carb and in with the spark plug. Could it be low compression and if so how to fix?

 

[antoniojgraves]

It backfires once in a while but not often.

 

[kendelrk]

your key is sheared, the flywheel and flywheel key slot must be in the same place to get the correct timing and fire at the right time, pull your starter clutch off, this will prove the key is sheared

 

[Doc Sprocket]

your key is sheared, the flywheel and flywheel key slot must be in the same place to get the correct timing and fire at the right time, pull your starter clutch off, this will prove the key is sheared

This sounds correct to me. The assumption is that you didn't correctly retighten the new clutch (and hence the flywheel). First pull or two would have sheared the key. Remove the flywheel again and inspect the key.

 

[antoniojgraves]

I will try it. Thanks

 

[antoniojgraves]

I have not tore took the flywheel off yet but I believe the key is okay because it doesn't jerk the cord back in. I got to messing with it and if I put a good bit of gas in the carb, it will turn over almost to a full crank and die. The guy at the shop said must likely it has lost compression but not sure.

 

[kendelrk]

even with a sheared key it will do this, even if it dosent jerk out of your hands its still off, like its about to start, then a second it dies, its the key

 

[Doc Sprocket]

Check anyway. It doesn't take much effort, and a shorn flywheel key does not guarantee that the starter cord will be ripped out of your hand. The ignition timing could still be out.

 

[kendelrk]

all you gotta do is yank off the recoil housing, put a screw driver on the flywheel fin and then take a flathead and beat the starter clutch to the left, if you see it not lined up, its obviously gone, and there not hard to replace, and its cheap, sometimes sheared keys baffle people, even people who know what there doing with engines still get baffled, when i got mine sheared i pulled off the starter clutch and the slot was in the 12 o clock position and the flywheel in the 3/12 position,

 

[antoniojgraves]

The key is fine I have removed the flywheel and it seems fine. Will post pictures in a little.

 

[Doc Sprocket]

Okay- we'll assume for now the ignition timing is okay then.
Are you 100% sure you have a GOOD spark?

Carefully inspect the wiring to and from the coil, including the kill wire AND the wire to the breaker points, if your engine uses points. Perhaps in the course of your repair you nicked/grounded out a wire. If your timing is okay and you have a GOOD spark, it will fire when you spray ether in the carb. You didn't alter the valve timing, did you?

I have seen an engine that had a weak spark that would not fire on ether, which is why I emphasize GOOD spark.

 

[antoniojgraves]

The spark is fine and the kill wire is disconnected and free from anything grounded. These are pictures of the shaft, flywheel, key.