Hey folks, I need a hand with my 1996 Bearcat 454. I bought it for 500 with a seized top end. I took it apart and changed the crankshaft, piston, cylinder, rings, and connecting rod. Everything rotates perfect. I cleaned out the carburetor put in a new spark plug and fresh gas and connected everything. The ATV will not start. I am trying to start it without the air box in and it spits gas through the intake. If I place my hand over the intake and crank it while giving it gas, it seems to want to start but just backfires and never starts. Spark is strong (blue) and compression is strong. All valves are adjusted within spec and timing is good. I am stumped. Is it necessary for the air box to be installed to get it running? Any help would be appreciated. Thanks.

 

When you cleaned out the carb, did you remove and clean the hidden strainer on top of the needle's seat?

 

Yes. I meant to update the post a few days ago. Turns out I didn't clean out the three small holes that were just after the throttle plate. It starts and idles great but I don't want to run it for too long because I don't have the radiator connected yet. Thanks for the reply.
P.S. Do you know any good online retailer where I can get a hold of new valve seals? Thanks.

 

Well I've replaced a bunch of them, but they all come with a head gasket set or valve cover gasket set. Recommend one source for all Arctic Cat OEM parts: Arctic Cat Parts and Accessories | Arctic Cat Parts House

Fast and cheap!

Greg

 

Thanks. I'm going to order one of those gasket sets that come with the seals instead of ordering them separate. It seems to be cheaper that way anyway. Thanks for your help.

 

Hey I was reading your post and we have a few of the same issues. I was wondering what you found your compression to be? I cannot find ANYWHERE what the compression is supposed to be. I measured mine and got about 55lbs. I have heard that these bikes have a de-compression valve to make turn over easier which shows a lower compression. Do you know if that is true? It runs great and strong, just burns some oil. I would really like to know what your compression was once the work was done and if you know about the de-compression valve.
Thanks,
John

 

Forgot to add that my bike is a 96' 454 4x4

 

I don't remember ever checking the compression on my Bearcat 454, but did on the 500 I traded the Bearcat for. I never did find a manual for the Bearcat, but if you use the specs on the 400 or 500 you should be in the ballpark. 50 sounds a bit low, but you need to have it warm and the throttle held wide open and crank it over at least 10 "pumps".

Greg

 

I think the electric start motors like the Bearcat had, did not have a compression release.

Greg

 

Hey navchapdoc sorry for the late reply. I did not actually do a compression test on my Bearcat. I said it had strong compression because I put in a new cylinder, piston, and rings. With that being said, I went to look up the actual specs for compression in my service manual and I couldn't find it anywhere. 55 lbs does seem low though. There is no decompression valve as far as I know. If you're burning oil you could have some wear in your rings/cylinder wall. You may also have worn out valve seals. I scanned the two pages of the manual that have all the specs and attached them. If there is anything else you need help with I'll be glad to help you out

-Nick