Autotech internals and the recent failure trends

[bacillus]

The part number for the 1.5" O ring that goes over the hpfp assembly is 06E 127 248 .   

[vRSAlex]

These were on really early AT pumps.  Ive not seen any seals going so far on any pumps.

[KRL]

The part number for the 1.5" O ring that goes over the hpfp assembly is 06E 127 248 .   

So is the part number for the spring energised seal?

These were on really early AT pumps.

Yes the early V1 pumps did have some problems with seizures but I have heard of no seizures at all from the V2s onwards

[muckipup]

The part number for the 1.5" O ring that goes over the hpfp assembly is 06E 127 248 .  

So is the part number for the spring energised seal?

I don't think so - I believe that is the O-ring that seals the entire HPFP too the engine whereas it is a seal internal to the HPFP causing an occasional problem.

I did about 15-20k on Autotech internals but you may know my story from another thread, my car is currently stranded down at JKM after failure of this OEM seal with Autotech internals and awaiting an APR pump to arrive in stock.   

[vRS Carl]

I've just put this in the other thread but i'll put it here too just for anyone who hasn't seen the other thread.

I don't think it's a failure of the seal per se.

My understanding is that due to the stepped design in the piston fuel gets in behind that step (due the the lubrication using fuel). Once the piston is on it's return stroke it is trying to compress the fuel. Liquid can't be compressed so the fuel has to go somewhere and it will inevitably choose the path of least resistance. Which in this case is past the seal.

So rather than the seal failing. It is being asked to do something it wasn't designed to, due to the step in the piston. So if Autotech re-designed the piston to be one diameter it's length then, in theory, this would solve the problem.

[muckipup]

So rather than the seal failing. It is being asked to do something it wasn't designed to, due to the step in the piston. So if Autotech re-designed the piston to be one diameter it's length then, in theory, this would solve the problem.

Yup, agree there - it wasn't designed for that. On saying that, the seal failed in mine however you look at it.

I believe APR swap out this OEM seal as part of their rebuild (and have a uniform piston diameter). I say that with caution as I am not some kind of APR fanboy, just conveying the info 

[Hurdy]

I did around 20K on the Autotech internals with no problems at all, including around 8k with the RS4 valve. No issues with the cam follower either.

[Sunglasses Ron]

19k on my Autotech internals with no problems (touch wood).. Even checked the oil (and had a sniff) the other day and all is well.. 

[muckipup]

The problem seems to be the actual seal not the internals, and again, only when the software demands a higher pressure.

So seal+software is the problem, the pump internals themselfes are just a stepping stone. Regardless, as a UK distributor of Autotech parts I am today sending them an email, I will update you with their response 

My experience backs your point up although I would caveat it by saying it is seal+software+the stepped piston Autotech internals might lead to a problem. Many others have been lucky, I wasn't.

I may have had an inherently weak OEM seal. I ran the Autotech internals for 15-20k without a problem. However, my software requested relatively low rail pressures below 5000rpm at that time. I did a K04 conversion, changed software to something that requested 130 bar across the board and at some point within 2 weeks had a failed seal with very apparent fuel to oil contamination.

To be honest, the contribution of the seal vs. the software vs. the Autotech internals is perhaps a bit academic to me. I needed the software to request the 130 bar of fuel rail pressure for Stage 2+ or Stage 3 performance, which it definitely did... and the point to an uprated HPFP is, of course, to deliver the 130bar!!  It is therefore difficult for me to separate these two.

I absolutely love the performance of the car at the moment so, if the OEM seal failed, I guess it's just the price I have to pay! I can't compromise on the software and ask for lower rail pressure with everything I have invested to get to Stage 2+ and then Stage 3. The only variables are therefore the HPFP stepped internals and the seal - for this reason, my only option is to get the APR pump which deals with both variables. This is despite having nothing against Autotech (it was my first choice after all) - it just didn't work out for me  .

The other possibility of getting a whole new OEM pump and re-fitting the internals in the hope that the seal will hold just doesn't make sense.

[chungster]

does the OEM piston have the same "stepped" design as that of the Autotech version?

Someone said the APR is solid piece and has no stepped design...so is there a reason why its "stepped" in the first place?

[KRL]

does the OEM piston have the same "stepped" design as that of the Autotech version?

Someone said the APR is solid piece and has no stepped design...so is there a reason why its "stepped" in the first place?

The OEM pump does not use a stepped piston.

The APR pump does not use a stepped piston, it uses a piston with increased diameter.  As the piston is a larger diameter than OEM it means APR also needs to provide new seals as the OEM seals will not fit with the larger diameter piston.

The Autotech pump uses a stepped piston.  This means they can increase the diameter of the piston and still use the OEM seals.

Increasing the diameter of the piston is what allows the pump to deliver more fuel to meet the higher rail pressures.

I think both solutions have their advantages and disadvantages and and what needs to be confirmed is if a stepped piston design really does increase the chance of a seal failure.

[muckipup]

The problem seems to be the actual seal not the internals, and again, only when the software demands a higher pressure.

So seal+software is the problem, the pump internals themselfes are just a stepping stone. Regardless, as a UK distributor of Autotech parts I am today sending them an email, I will update you with their response 

My experience backs your point up although I would caveat it by saying it is seal+software+the stepped piston Autotech internals might lead to a problem. Many others have been lucky, I wasn't.

I may have had an inherently weak OEM seal. I ran the Autotech internals for 15-20k without a problem. However, my software requested relatively low rail pressures below 5000rpm at that time. I did a K04 conversion, changed software to something that requested 130 bar across the board and at some point within 2 weeks had a failed seal with very apparent fuel to oil contamination.

To be honest, the contribution of the seal vs. the software vs. the Autotech internals is perhaps a bit academic to me. I needed the software to request the 130 bar of fuel rail pressure for Stage 2+ or Stage 3 performance, which it definitely did... and the point to an uprated HPFP is, of course, to deliver the 130bar!!  It is therefore difficult for me to separate these two.

I absolutely love the performance of the car at the moment so, if the OEM seal failed, I guess it's just the price I have to pay! I can't compromise on the software and ask for lower rail pressure with everything I have invested to get to Stage 2+ and then Stage 3. The only variables are therefore the HPFP stepped internals and the seal - for this reason, my only option is to get the APR pump which deals with both variables. This is despite having nothing against Autotech (it was my first choice after all) - it just didn't work out for me  .

The other possibility of getting a whole new OEM pump and re-fitting the internals in the hope that the seal will hold just doesn't make sense.

Well, after a slight delay for the APR to arrive, it is now fitted so I'll see how I get on. I have to admit, the cost of the pump plus an oil/filter change 2 weeks after a service when it was already done was a bit painful but something I had to 'take on the chin'!

[Hedge]

Glad to hear you are back up and running Dave 

[muckipup]

Glad to hear you are back up and running Dave 

Me too, Ian...I have been driving SWMBO's Y-reg Focus 2 litre where I think a 'few horses have died' over the years  . Building up enough speed on A3 slip roads was a drama! A bit off topic but I swear I was in more tricky situations and at the mercy of more pi$$-takers on the road in the 10 days that I had that car through lack of power than I have been in the entire time I have had a sooped-up VRS!

[Janner_Sy]

good to here dave.  Lets hope it all stays trouble free for you now.