Intek 21 HP engine wont start!!!

[jmartin99]

I just got my 21HP Intex engine rebuilt and put back together. After putting oil in it and turning on the fuel I attempted to fire it. Standing to the side of the mower I pushed the brake lever with my foot and turned the key. It started!! and ran great for 30 seconds....then died!!! I turned it over again and nothing!! Then I thought about it and it should have never started to begin with because I was not on the seat and there is a pressure switch in the seat that prevents it from running without someone sitting in the seat! So I got in the seat and nothing! It is actually backfiring through the carb now!!

I am positive I lined up the timing "dots" on the crank and the cam!

I pulled the plug and I have plenty of spark!

Any ideas what could be wrong?

HELP!!!!!

 

[Rivets]

My first guess is that the flywheel nut was not torqued properly. Now you have a sheared flywheel key. I would start there, pulling the flywheel and checking the key.

 

[jmartin99]

You nailed it!! The key was sheared.

Ok, what is the torque on the flywheel nut supposed to be? I will get another key tomorrow and hopefully have this thing running again!

Thanks!

Jeff

 

[bertsmobile1]

Two grunts & a groan.
If you are using normal hand tools you won't be able to overtorque it.
If you break the top off the crank, then let me know there is a place for you in the Mr Universe quest:laughing:

Around to 70-80 Ft/ lbs is where most go.

 

[ILENGINE]

Without knowing your model number there was a few models that used a bolt for the flywheel, and I can't find it right now but seem to remember the torque was 75 lb/ft and the single cylinder intek engines with the nut have a torque of 100 lb/ft and the intek twins with a 1-1/4" nut is 150 lb/ft.

 

[reynoldston]

Two grunts & a groan.
If you are using normal hand tools you won't be able to overtorque it.
If you break the top off the crank, then let me know there is a place for you in the Mr Universe quest:laughing:

Around to 70-80 Ft/ lbs is where most go.

Sound like he didn't put the groan in after the two grunts :laughing:

 

[Tinkerer200]

Note there are two 21 hp B&S Intek engines with different specs.

Walt Conner

 

[jmartin99]

Ok, so I replaced the flywheel key yesterday and it pops over with ether but will not run on gas. Is it possible the carb might have been damaged when it backfired?

I still have last years gas in it so I think I will drain it and put some fresh gas in it tonight.

Any other things I might try? Running out of ideas!

Thanks!!

Jeff

 

[pugaltitude]

I still have last years gas in it so I think I will drain it and put some fresh gas in it.

You have just answered it!

 

[jmartin99]

The thing is the first time I tried to start it when it sheared the key it ran great for 30 seconds without any ether!!

Jeff