990 lost prime.....help

ryeguy

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I had the same problem on a 813 that sat for awhile. It took a while to get it fired. I ended up tossing it in favor of a new one. I just did not trust it
That's what I am thinking but I may try to clean it out or check my fuel lines to see if they are cracked or leaking before I toss it.
 
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jbooker82

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Another thing you can try is to spray carb cleaner in both the inlet and outlet. When your spraying carb cleaner in the bottom inlet pump the bulb. If you do this while the carb is together the diaprams wont curl. If you get carb cleaner on them while it is tore apart they will curl up, but they usually flatten back out when they are fully dried. Its worth a shot since the next step is the trash can.
 

Monsterman

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+2 remove it from the motor, try letting it soak in some carb cleaner or gasoline. I had the same shit happen but I didn't want to just toss it in the trash. Ended up letting it soak over night in carb cleaner. Re installed and it worked fine the day I ran. Let it sit again for about a week or so and stuck again, ended up rebuilding it after that. Havent had anymore probs out of it since the rebuild..

Good luck Ryan.
 

Monsterman

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Great info thanks guys.
Chris, what's involved in a rebuild??

I disassembled the entire carb. I've become kinda an expert on taking them apart. I think I've taken apart, rebuilt and put back together 10 or so 668's and a few 990 & 813's by now..

Now that I think of it I might have a 990 kicking around I could send your way if you end up needing one :cool:
 

jbooker82

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GT4point6

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Ramona, Ca
I have the same problem, replaced all the gaskets, primer bulb, and diaphrams. Still sucks air in and won't prime. This happened on a stock 668 after 1.5 hours, HPI just sent me a new one, now I still have a 990 with the same issue and it lasted about 10 hours before this happened. I'll try carb spray but since I've replaced the diaphrams already, not sure it will help much.
What else can cause this?
 
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