Hi,
I know this has been covered on the net on various forums, but having just done the pump change I can add a little extra detail that might help others.
The standard pump is still available from Porsche UK for around £700 in mid 2024. Following the advice from others, I chose to fit a standard Bosch pump instead. The pump I chose was Bosch, part number 0392020039, costing £60 from Opie Oils. Some people have used pump 0392020024 instead, however close comparison of these two Bosch pumps shows that the connector for the electrical supply is different. I can't vouch for what plug you need for 0392020024, but I can for 0392020039 - see below.
I wanted to retain the existing circular section plug and socket that connects the old pump to the chassis harness. These items are Sure-Seal 120-1807-000 and 120-1804-000. However, looking into the assembly of this plug I realised I would not only need a special crimp tool but also a special pin insertion tool. To keep the cost down I chopped the old cable off the old pump and fitted a plug to the chopped end that was compatible with the new pump.
The parts you need to match up to the new pump are AMP/TYCO 2 Way Junior Timer With Terminals Boot and Cable Seals. Part numbers:
Housing/Plug. 827551-3, Terminals 925596-1, Wire Seals 828905-1. I bought some spare terminals for safety, the lot came to less than £10. Again you need a special crimp tool, my standard crimp tool didn't work. So instead, I soldered the bared cables into terminals. Once you've collapsed the terminal cable support lugs with need nose pliers, the terminals push into the plug without any tool.
The new Bosch pump turned out to be about 30mm taller than the old Porsche pump. But there is plenty of space above this pump when installed so this causes no issues nor detracts for the tidiness (is that a contradiction on a 944 turbo?) of the engine bay. The pump body diameter is the same on both pumps, the OEM clamp that supports the pump fits fine.
However, the fluid ports on the new pump are about 1-2mm larger diameter! Using some Dow Corning MS4 gel as a lubricant I was able to get the hoses onto the new pump. Panic over.
I was slow and methodical, cleaning things as I went. I needed to take off a lot more parts for access than I expected (throttle, pump bracket, pump bracket backing plate, J boot, pipe into throttle, pipe from wing to air filter housing). It took me 6 hours.
By keeping one hose high and the other jammed with a chinograph pencil (the first thing that came to hand!) I managed to only lose about a pint of coolant.
The new pump seems to flow more than the old one, based on turbulence in the header tank when it operates. I'll try and upload some photos too.
I know this has been covered on the net on various forums, but having just done the pump change I can add a little extra detail that might help others.
The standard pump is still available from Porsche UK for around £700 in mid 2024. Following the advice from others, I chose to fit a standard Bosch pump instead. The pump I chose was Bosch, part number 0392020039, costing £60 from Opie Oils. Some people have used pump 0392020024 instead, however close comparison of these two Bosch pumps shows that the connector for the electrical supply is different. I can't vouch for what plug you need for 0392020024, but I can for 0392020039 - see below.
I wanted to retain the existing circular section plug and socket that connects the old pump to the chassis harness. These items are Sure-Seal 120-1807-000 and 120-1804-000. However, looking into the assembly of this plug I realised I would not only need a special crimp tool but also a special pin insertion tool. To keep the cost down I chopped the old cable off the old pump and fitted a plug to the chopped end that was compatible with the new pump.
The parts you need to match up to the new pump are AMP/TYCO 2 Way Junior Timer With Terminals Boot and Cable Seals. Part numbers:
Housing/Plug. 827551-3, Terminals 925596-1, Wire Seals 828905-1. I bought some spare terminals for safety, the lot came to less than £10. Again you need a special crimp tool, my standard crimp tool didn't work. So instead, I soldered the bared cables into terminals. Once you've collapsed the terminal cable support lugs with need nose pliers, the terminals push into the plug without any tool.
The new Bosch pump turned out to be about 30mm taller than the old Porsche pump. But there is plenty of space above this pump when installed so this causes no issues nor detracts for the tidiness (is that a contradiction on a 944 turbo?) of the engine bay. The pump body diameter is the same on both pumps, the OEM clamp that supports the pump fits fine.
However, the fluid ports on the new pump are about 1-2mm larger diameter! Using some Dow Corning MS4 gel as a lubricant I was able to get the hoses onto the new pump. Panic over.
I was slow and methodical, cleaning things as I went. I needed to take off a lot more parts for access than I expected (throttle, pump bracket, pump bracket backing plate, J boot, pipe into throttle, pipe from wing to air filter housing). It took me 6 hours.
By keeping one hose high and the other jammed with a chinograph pencil (the first thing that came to hand!) I managed to only lose about a pint of coolant.
The new pump seems to flow more than the old one, based on turbulence in the header tank when it operates. I'll try and upload some photos too.
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