1997 Mercery 250 EFI (2 stroke)-Replace high pressure (VST) pump

[jkscarab]

High pressure fuel pump went bad. Mechanic wanted 3 weeks and ~$1400 for repair.
So with the help of this group I am going to attempt the pump replacement DIY.
Left photo below shows the brass barb fitting on the pump and right photo NO brass bushing on the replacement pump.
combo pump pics.JPG
Questions:

1. I assume I simply reuse the brass fitting from the original pump and mount on new pump?
2. Any “tricks” to get the old pump out of the VST housing? High side fuel pressure pump is ~100psi so the pump must be in super tight
3. Any brands of after market fuel pumps work well?? Or do most here sping the $750 for the OEM Merc part. I order the quantum pump good/bad ??

Thanks for any thoughts!!

[JOE54]

do you ave a serv manual for your engine , brass fitting is component of vst not pump , please use 3.0Lforum 2 more down list for more info on your engine

[EuropeanAM]

Also- where did this aftermarket fuel pump come from?

Moving your thread to the 3L Forum for you. Please be sure to update your thread with the engine serial number.

[lpugh]

I would recomend not using that pump
At least crossover the part number on your pump to a Walbaro pump

[jkscarab]

Walbro does not have a compatible to the merc part number 809088T. Thanks for the message though...

[jkscarab]

do you ave a serv manual for your engine , brass fitting is component of vst not pump , please use 3.0Lforum 2 more down list for more info on your engine

Yes, I ordered the manual and it arrived today. So, yes as you say the brass fitting is part of the top housing VST now part of the pump. Thanks

[jkscarab]

Also- where did this aftermarket fuel pump come from?

Moving your thread to the 3L Forum for you. Please be sure to update your thread with the engine serial number.

I ordered from Quantum directly. A friend put that pump on his Merc with good luck so far (only one year of service)...so too early to tell if it has good longevity

[EuropeanAM]

For assistance with the pump and it's proper fitment (it is not an OEM pump), Quantum should be able to assist you with pertinent instructions and details as they should have tested the pump in the application it's sold for.

There's an o-ring on the top-hat, and there's two o-rings on that brass flange. They're difficult to come by because they were sold in a very-pricey connection kit (which in many cases is now NLA).

[jkscarab]

For assistance with the pump and it's proper fitment (it is not an OEM pump), Quantum should be able to assist you with pertinent instructions and details as they should have tested the pump in the application it's sold for.




There's an o-ring on the top-hat, and there's two o-rings on that brass flange. They're difficult to come by because they were sold in a very-pricey connection kit (which in many cases is now NLA).

Are you refering to the gaskket "C" as shown in my pic/drawing??? I did not get that gasket with my pump kit. Maybe I should buy that C gasket separately as its the key interface from pump to VST. Thoughts??exploded fuel.jpg

[Rick H]

Guess I crossed some kind of line.

Hope it helped you JK

[jkscarab]

Guess I crossed some kind of line.

Hope it helped you JK

Hey Rick H. I do not see any response from you on the question "replace high pressure pump". What do you mean "you corssed some kinda line"?

[Rick H]

Hey Rick H. I do not see any response from you on the question "replace high pressure pump". What do you mean "you corssed some kinda line"?

My replies were deleted by the sand box commander.

[jkscarab]

My replies were deleted by the sand box commander.

Oh, I understand. I am open to being critiqued etc. I dont claim to have any special knowledge/mechanic skills (but I am a degreed mechanical engineer). Any help is appreciated....perhaps you could rephrase your comment to not get block by Mr. Sand Box.

[EuropeanAM]

Are you refering to the gaskket "C" as shown in my pic/drawing??? I did not get that gasket with my pump kit. Maybe I should buy that C gasket separately as its the key interface from pump to VST. Thoughts??exploded fuel.jpg

"C" as you have it labelled would be the top-hat seal (O-Ring).

I'd offer a friendly suggestion to refrain from the sandbox comments. See the Forum Announcements for information on what is/is-not acceptable in the the forums (not the least of which is the primary manufacturer's name).

jk: If you need a top-hat seal, we should have some of those available by special (email) request through our Parts Department (they would be an Integrity Injection component).