2000 gtx 951 crank no start with backfire - have spark

[jas0405]

Hello,
I'll jump right into it. At the end of the season last year we had our SBT engine sieze.
We had a reputable tech from Bass Pro that we knpw work on it for us and install our replacement enigne from SBT.
I did not get it back untill after season was over has been stored in warehouse where i work. heated and cooled.
Getting ready to go out this weekend and started getting everything ready.
And guess what. You guessed it! it will not start! LOL! never heard that before have ya?!
I put in a new full charged battery! And spark plugs.
It cranks over great and i dont hear anything abnormal unitll ... Bam it backfires while iam cranking it over.
double checked plugs - they were correct and while i had them out turned it over for giggles to verify spark. It was good.
Fresh gas , Fresh oil, fresh plugs, fresh battery, fresh engine!!!! got spark - got fuel obviously if backfiring - plugs had oil on them so go oil too!

Any suggestion on where to start looking? Possible injector or pump?

[Technical Support]

Re: 2000 gtx 951 crank no start with backfire - have spark

Has it been started since the new engine was installed?

[dsolie]

Re: 2000 gtx 951 crank no start with backfire - have spark

Fuel Selector turned to ON? Choke pulled out while trying to do it's initial start?

[jas0405]

Re: 2000 gtx 951 crank no start with backfire - have spark

yep gas is on and choke is out and no this is the first time it has been started since the new engine has been put in.
in my yammering last night i put fresh gas that is not correct it is old gas and my brother in law put in sea foam. and now looking thru some other post i see that some one reccommends to flush out old gas and run new and that even adding an additive like sea foam will not help. I'll try that as well.

[Technical Support]

Re: 2000 gtx 951 crank no start with backfire - have spark

If the guy that put your engine in has removed the flywheel from the magnet cup at some point Then I would bet that he didnot put the magnet cup back on the way it needs to be. It needs to be aligned properly, the 6 bolts that hold the cup to the flywheel hold the 2 together in a exact position for timing.

[kneeboardpro9]

Re: 2000 gtx 951 crank no start with backfire - have spark

I had this same problem when i changed my 951. It was the magnet cup on the flywheel. pull to front cover, and make sure the cup is aligned properly. I had some pretty significant backfires when I did mine. kinda fun but not good!
Make sure it is lined up and that should be your problem!