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My camshaft plug for the high pressure fuel pump was broken in pieces, with much of it MIA, and as I go to install my new expensive white one, I can only imagine the new one will just break apart in time as the plastic ages. I am curious what you all think is the purpose or benefit of the plug, since this area is sealed from the outside world, so why introduce something that can break apart and possibly send pieces throughout the engine? Just an unnecessary assembly aid?
I suspect it's to account for machining variances during production. If you had a metal-to-metal drive system it would require the shaft to be exactly aligned with the camshaft. And it may also serve as a sacrificial coupling - think what would happen if the HPFP somehow jammed up solid and wouldn't turn. Not good at all for the entire cam assembly and drive system. Having a purposeful weakest component is often a good idea in that sort of situation.
I think it keeps the coupling in so it won't fall out after you remove the pump. It is a VERY expensive piece of plastic. Probably one cent worth of plastic.
Is the HPFP supposed to turn freely? Just curious why you ask, since mine, which was working fine, is pretty stiff. I removed the pump to access the coolant line that I pinned on the rear engine crossover.
The drive is metal-to-metal the entire way; I ifigured, as Doug says, that it just holds things together for assembly or disassembly. Just seems odd that if you don't need the aid, to have it there to just break and send pieces flying throughout the engine.
Is the HPFP supposed to turn freely? Just curious why you ask, since mine, which was working fine, is pretty stiff. I removed the pump to access the coolant line that I pinned on the rear engine crossover.
The drive is metal-to-metal the entire way; I ifigured, as Doug says, that it just holds things together for assembly or disassembly. Just seems odd that if you don't need the aid, to have it there to just break and send pieces flying throughout the engine.
And yes, that plug is $50... Uggh!
I suspect the HPFP is a positive displacement vane pump, so some resistance to turning is normal, the vanes are always pressed out against the housing. Interesting that the plastic bit appears to be an assembly aid. I would have guessed a weakest link sort of thing, but perhaps I'm giving the German engineers too much credit to admit that occasionally something they design might break, leading to a cascading failure grenading the engine. I should remember the Variocam bolts I guess.. Happily I haven't had the need to replace that bit of plastic.
BTW - if you're in my neighborhood and want to pin my connector, feel free to contact me. I'll even buy you beer and give you a beach badge to use.. I have the tools but lack the ambition at the moment.
BTW - if you're in my neighborhood and want to pin my connector, feel free to contact me. I'll even buy you beer and give you a beach badge to use.. I have the tools but lack the ambition at the moment.
Sounds like you're near my neighborhood once or twice a year... I'm in San Diego. Jay said he'd let me know when you're around next time so I could join you all for some socializing.
Sounds like you're near my neighborhood once or twice a year... I'm in San Diego. Jay said he'd let me know when you're around next time so I could join you all for some socializing.
Cool - possibly later this year if I can come up with a way to get SWMBO there that doesn't involve me driving or her flying. I'm thinking put her on the train and I'll take the motorcycle...
06-20-2019, 01:49 AM
what's the point of the HPFP cam plug?
I have the tools but lack the ambition at the moment.