[Jednlulu113]

Great forum. I've learned a lot about small engines and the mechanics of various "toys" from these threads.
So, I have a 1991 EZGO Marathon Utility cart (venture with Jacobsen). My kids and I were pulling a small trailer whilst picking up rocks in the yard. All the sudden, while attemping to take off, she started spitting and sputtering and backfiring through the carb. I immediately suspected that the cam lobes were worn down because when I rebuilt the motor last year (sleeves were in service limit i.d. so rings were replaced and rockers where really worn down). I never even looked at the cam closely during the rebuild so, hence my assumption due to the condition of the rockers (which by the way did get replaced).
Anyway, I tore the top end off and the cam actually measures out well within the service limit (lobes). The only slight concern is that the free end (opposite of timing gear) was right at the low end of the service limit. So, I assume since rockers are new, that stack up of tolerances together should be ok.
So I move to the valves. Intake valves check out great, nice chamfers, mating all ok. Exhaust valves however, whew, what a mess. Couldn't believe it had ran that long with that condition. So, I replaced the valves (had seats ground by a local machine shop). Did the test with pouring fuel into the exhaust port...checks out great. Did same for Intake side...check, all good.
Got things all back together, new timing belt, new valve seals, new gaskets and such and she still spits and sputters upon attempting take off. She'll do this for about 5~8" and then finally fire and get moving. Once moving, all is ok and she runs good. It's just that initial take off now that's troublesome. From a cold start it takes more like 15~20" to get going, improving to 5~8" when warm.
I did check the vacuum line to the fuel pump and she's nice and tight at both ends. No improvement.

Any advice out there on what I should have a look at next?
Thanks for any insight / opinions / advice.
Jed