I have a 99 mxz 670 ho. It ran fine until last weekend. Now, whenever you hammer on the gas, it takes off hard, then falls completely on it's face and bogs down. backing off the throttle completely for a bit then getting back on it works for a second again, if you just hold it at half-open it kinda wants to pull but won't rev up. Occationally it'll stall completely and won't start again. I did have the engine out last weekend to fix the steering bushing strap, with no problems before that, and so therefor assumed it had something to do with the work i did...but i quadrouple checked all of that, with no problems found (engine allignment, fuel line kinks, etc).
I've taken the carbs apart, found nothing wrong, removed the fuel filter for testing, put isopropyl in it, changed belts (not to a new one, but a usable spare), plugs, the norm....then i pulled the pump, and if i blow into the pulse port from the crankcase, i can get air to leak out of the intake or output, don't remember. i'm pretty sure it's the pump at this point, i believe it would explain all of my problems, but there's no rebuild kit for them and they're $100, special order so no return. I'd like to be sure that this is the problem.
Any ideas? thanks...
nik
I've taken the carbs apart, found nothing wrong, removed the fuel filter for testing, put isopropyl in it, changed belts (not to a new one, but a usable spare), plugs, the norm....then i pulled the pump, and if i blow into the pulse port from the crankcase, i can get air to leak out of the intake or output, don't remember. i'm pretty sure it's the pump at this point, i believe it would explain all of my problems, but there's no rebuild kit for them and they're $100, special order so no return. I'd like to be sure that this is the problem.
Any ideas? thanks...
nik