vro or vacuum switch?

[44automag]

i have a 87 200 xp and just rebuilt the vro pump and it will pump gas when i suck and blow on the vacuum hose but not when hooked up to the engine. Does the vacuum switch have anything to do with this or is there another problem? I have heard that the vro pumps are very picky about being rebuilt. Do I need to just buy a new pump?
any help would be appreciated

 

[Dhadley]

Re: vro or vacuum switch?

The vacuume switch doesn't have anything to do with this issue. Is there a flame arrestor in the pulse line or does yours use the one screwed into the block? Whichever one your motor uses you might check to see if it's clogged which will restrict the pulse.

 

[bassmaster75022]

Re: vro or vacuum switch?

after lots of trail and error i found that the o ring on the inlet nipple was bad and causing a air leak intermittently also i would use the pinch clamps or hose clamps on all the lines zip ties dont get tight enough another thing i found out in testing just thought id pass this along because i have never seen any post on the clamps vs zip ties it does work a lot better

 

[44automag]

Re: vro or vacuum switch?

I replaced the pulse limiter that screws into the block. I also used clamps on all conections. how much vacuum and pressure should there be on the vacuum line out of the block?