HPFP O-rings

ibcrusn

Greenie N00B Member
Greenie Member
I can't take credit for pulling the basic part number list together but I did measure a few and make sure our friends at McMaster-Carr had standard Buna-N and Viton versions available.

From my post on the other forum....

Links take you to McMaster-Carr

HPFP housing
ID = 32mm
T = 2mm
Buna-N 9262K197
Viton 9263K523

Piston Housing
ID = 23mm
T = 2.5mm
Buna-N 9262K535
Viton 9263K698

Internal Piston Housing (Double Seal or X-ring)
ID = 8mm
OD = 12mm
Buna-N No longer available from McMaster Carr
Viton TBD
Note: I've found alternate suppliers for metric x-rings but I do not have access to a pump to measure. From what I found none seem to use even measurements, 1.78 or 2.62 mm cross section. If anyone can measure one and find another source I'm happy to update.

Spill Valve
ID = 27mm
T = 2.5mm
Buna-N 9262K257
Viton 9263K307

For those that have a need to replace all the o-rings in the HPFP here's the last two. You'll need a tamper proof T25H Torx bit to remove both.

Inlet/bypass tube assy
ID = 8mm
T = 2mm
Buna-N 9262K169
Viton 9263K169

Diaphragm Cover
ID = 33mm
T = 2.5mm
Closest standard o-ring AS568A-125
ID = 1.299"
OD = 1.505"
Buna-N 9452K89
Viton 9464K89

7/18/2020 Uploaded a PDF version of my Google Doc
 

Attachments

Last edited:
Thanks, saved this info in a file in case I need something down the road.
 
Just curious if anybody has tried the double seal o-rings listed above for the internal piston housing (being that they are undersized)? was going to order a pack of 50-100 of each of the meth/eth safe o-rings listed above, rebuild a spare pump...and possibly put together cheap pump o-ring kits to sell.
 
Just curious if anybody has tried the double seal o-rings listed above for the internal piston housing (being that they are undersized)?

I have not purchased the "X" o-ring yet. I don't run much more than a couple gallons of E-85 in the warmer months for some octane margin and I don't tune for it. Not running higher concentrations and more often I have no reason to tear apart the pump yet for a refresh or remove black death, maybe some of the guys regularly running E-85 can comment.
 
Just put the McMaster-Carr dash 011 o-ring in my HPFP today (with some fresh Rotella T6)..did a test drive tonight and the air coming out of the BOV smells like pure gasoline (I have an oil cap breather in line with a BMW cyclonic seperator that is plugged on the intake)...fucking pissed off...will check the oil level tomorrow morning
 
Just put the McMaster-Carr dash 011 o-ring in my HPFP today (with some fresh Rotella T6)...

Which o-ring from the list above correlates to the -011? The X-ring? If so are we to assume it was one of the standard spec x-rings and not the metric Buna-N part?
 
For anybody interested, i have spent a lot of time and money putting together a complete hpfp o-ring rebuild kit. All o-rings are Buna-n (meth/eth safe) metric size, properly measured and test fit on a spare pump, ran on my DD. I dont have enough posts to sell here and cant post outside links, but if you look on the other site or the common mazdaspeed FB pages...you will find them.
 
Can anyone confirm that these Oring part numbers to rebuild the HPFP are correct?

The main ones I'm concerned about are the two screw seals.
 
Just confirming that all the Oring part numbers in the OP are correct, and they all work. Only have about 50 miles on them from driving to work, but so far so good and LTFT are back to normal.

The Xring for the inner screw seal is the same design as OEM. I used just a thin lace of motor oil to install each Oring.

Thank you @ibcrusn for posting these part numbers!

20200316_135312.jpg
 
Glad to hear they all worked well for you.

I double checked my Drive folders and since it's been over a year since I sold my MS3, I seemed to have deleted the folder hosting the Google Doc with the info. Thankfully the important stuff with McMaster Carr links is hosted here. It's been over a year since I had to sell mine (new to me company car) and my daughter is still bummed and says she misses the red car and her "racing" seat about twice a month.
 
Hi, Rob from Sydney Australia.
I fired up my mps 6 after rebuilding my HPFP with Autotech internals and Michael Rey's seal kit. All seems OK, the engine starts and idles smooth, according to my AP, fuel pressure averages around 1700psi, I replaced the engine oil and filter before I fired it up and after driving it for about 1/2 hour, the oil on the dipstick and Oil cap smells like fuel. I have never taken notice of the smell of the oil before, is this normal for this engine or could the Quad ring or X-ring be leaking fuel into the engine, has anyone seen this before.
Any advice or info would be greatly appreciated.
 
Back
Top