Dellorto PHF 36's Accelerator Pumps won't spray

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Jimbarillaro
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Dellorto PHF 36's Accelerator Pumps won't spray

Post by Jimbarillaro »

I have just bought a 1981 Pantah 500 and recently rebuilt the carbs. The bike starts right up but I cant get the accelerator pumps to spray any fuel. I took the carbs back apart and checked everything. I also took the pump housings off and sprayed carb cleaner in the hole that transfers fuel to the nozzle and it's not blocked. The bike sat about 6 years before I bought it so I also replaced the petcocks and the fuel line. Is there a way to prime the pumps? What would cause fuel to not reach the pump housing? Any help would be greatly appreciated.

Thanks, Jim
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BevHevSteve
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Re: Dellorto PHF 36's Accelerator Pumps won't spray

Post by BevHevSteve »

Jim, take the non return valve out of the housing and drop in a few drops of gas. Remove the top cap stick your finger down the top and push the pump cylinder thing in repeatedly until you get gas squirting out.
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Jimbarillaro
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Re: Dellorto PHF 36's Accelerator Pumps won't spray

Post by Jimbarillaro »

Thank You Steve,
I will try to prime the pumps in the next few days and post the results.
Jim
Jimbarillaro
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Re: Dellorto PHF 36's Accelerator Pumps won't spray

Post by Jimbarillaro »

Hi Steve,
I got the pumps primed last night and the pumps are spraying great. The bike started right up and sounded good for about 30 seconds then it died. For some reason it won't start at all now. I think it may be an ignition problem so now I need to figure out whats going on.
Jim
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Re: Dellorto PHF 36's Accelerator Pumps won't spray

Post by radecal »

Have you checked to see if you have spark at the plugs?
This will eliminate the ignition issue and point to something you may have done in the removal and refit of the plugs.
RAD
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redorca10
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Re: Dellorto PHF 36's Accelerator Pumps won't spray

Post by redorca10 »

Even today that post is still relevant.
I had exactly the same problem. pull the carbs apart again, no blockages. As @BevHev Steve suggests, stuck my finger down and pushed the cylinder pumpy thing until petrol squirted out the acceleration jet. Bingo, I have created life!!! Legend. -?- -?- -?-
I think they must get an air lock in the tubes somewhere.
Now to balance them.
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BevHevSteve
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Re: Dellorto PHF 36's Accelerator Pumps won't spray

Post by BevHevSteve »

gas evaporates...... So if the bike has sat for any time you may need to put a teaspoon of gas in the housing , finger over hole and pull the throttle cable to get gas in there aka PRIME THE PUMP. once primed you are good to go assuming the pump jet is not blocked as that hole is TINY and easily blocked..
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