JKM appreciate that some people would like to know more about why we have made the switch from KMD & Autotech TFSI fuel pump internals, over to the complete APR pre built and tested unit.
Where we have been using KMD/Autotech internals I will detail what process we have been going through for each fuel pump prior to sending it out to a customer, so you will get a feel for the process that needs to be run through by JKM to ensure that the pumps are of sufficiently high quality to sell to a customer.
After receiving the fuel pump internals from the manufacture (say for example KMD) we first check the machined parts for known manufacturing problems by measuring and a general visual inspection – any problems here and the pump internals are rejected.
We then hand assemble the parts together and with a light lubrication between the piston and bore, the clearance and general feel is assessed. The internals are then hand assembled into a test fuel pump body - any problems here and the pump internals are rejected.
Assuming that all is good on the above, we can then begin an up rated fuel pump internal build into a brand new OEM pump.
Cleanliness is paramount here as any debris etc will ruin the piston shaft. This is something that we only do in an extremely clean environment to ensure the utmost quality.
Once the fuel pump is built, we then move onto the next main step – Testing.
To ensure that each TFSI fuel pump that we supply is of the highest quality we have been testing each pump built by JKM, on our own TFSI car.
Therefore every time we build a new pump Kates nice new shiny Mk5 GTI is pulled apart and the test pump is installed for performance testing under load. Following the install we analyse each fuel pump in detail.
We will look at the fuel pumps Quantity Valve differential angle, Total Compression volume, Fuel pressure and more – again comparing the results against known good units.
With our experience of these pumps it is possible to analyse the results and detect possible problems with internal clearances as a result of machining tolerances, but this is a very complex area. If we suspect problems we will remove the fuel pump, disassemble and inspect it again – any problems found here and the pump internals are rejected.
Following all of the above, assuming that the built TFSI fuel pump is functioning correctly, we will remove the fuel pump from our test car, seal it into a bag and box it and send out to the customer.
The main reason we have chosen to swap from KMD/Autotech is that the above is very costly to us (time wise) to get a good pump together. We have sometimes had to build 3 pumps to get 1 good unit.
We appreciate quality engineering, which APR provide with their fuel pump,
Our equivalent of the APR test rig, is our own MK5 Golf GTI engine and our diagnostics knowledge.
APR does have a superior hardware design, changing much more than just the piston and bore. The complete internals are re-engineered, right down to the balanced seal rings and main spring assembly. This design puts less stress on the rear balanced seal than the other pump solutions – the APR pump design is along the same route as the OEM pump only obviously containing larger internals for increased fuel volume.
APR route out bad pumps themselves during testing at their own facility, and the pumps have even been used by VW Motorsport on the VW Scirocco GT24 which won the ADAC 24h Race without any fault.
For those interested more information on this can be found here:
http://forums.vwvortex.com/zerothread?id=3855643JKM will only bring to market the quality items. If we find that the quality of an item is not acceptable we will first try and work with the supplier for a solution but ultimately if we would not be happy to use the product on our own car we will not sell it to a customer for use on their car.
For JKM the up rated internals route (only) is too inconsistent from the manufacturers.
APR provide a quality fuel pump out of the box, and the customer is in the knowledge that there will be no issues.
The APR pump can be bought in 2 ways; we will be updating our website shortly to include the cheaper core exchange route.
1) An outright buy of an APR pump, where by you can remove your stock TFSI pump and retain it somewhere safe and simply install the APR pump. This route costs
£624+Vat excluding postage back to you.
2) The second route is a core exchange, where by if you send us your TFSI pump we will send it to APR for a pre built unit, this route costs
£509+Vat excluding postage back to you and you are responsible for postage of your pump to JKM intially.
For those customers already with a JKM built KMD or Autotech pump, you do not need to worry as we have done the above testing process on your pump to ensure you have a good unit. I hope this helps clear up the questions in this area and hopefully you will appreciate why we have made the switch to the APR unit.
For those who wondered, our own car does use an APR fuel pump but the K04 conversion car that has been on long term testing (20,000 miles) has been, and is still using a KMD pump without fault.
JKM
