I've not been back into the garage to check yet .. but can I do this without removing the pump ?
just confirming its these and I turn them clockwise ? ( one of your photos I think Mark )
I've not been back into the garage to check yet .. but can I do this without removing the pump ?
just confirming its these and I turn them clockwise ? ( one of your photos I think Mark )
Yes, Thats the correct one's. You can keep the pump on the engine but when you remove the idle plate over 1/2 quart of oil will pour out.
Mark Jung
MFI Werks
Early 911S Registry #972
Carrera T w/LWB, MT, RWS, PCCB
72 T 66 x 100 MFI Twin Plug Coupe
R Gruppe #686
Huge thanks for the help Mark…. I kept the pump in place , removed the fuel cut off solinoid for access … and then using a vets syringe sucked oil out of the pump so as not to get spillage when removing the idle screw plate…. Also had to modify some tools to allow me to loosen the screw head that’s located closest to the shroud. Anyway, managed to get it sorted and adjusted to the two high speed screws by 2 clicks CW .Originally Posted by 2.5MFI
Having reinstall everything ( refilled the pump with oil) including the thermostat and adjusted the main rack back to near where it was , initial testing looks to have solved things with the top end afr’s now stable .
I’ll get some high temp testing done soon to confirm And to dial in the afrs
Pic
Great Idea. I forgot about that syringe method. Nice work.
Mark Jung
MFI Werks
Early 911S Registry #972
Carrera T w/LWB, MT, RWS, PCCB
72 T 66 x 100 MFI Twin Plug Coupe
R Gruppe #686
Just to update this .
After doing the above work, I still had the afr leaning at around 7000rpm. Lots of thinking and went back to basics. Now, I run a clewett twin plug ignition system which has a 3 step limiter . it had crossed my mind at the beginning it could be related to this, but For some reason I’d always assumed when the ignition was cut the afr’s would become rich. Reading up about these things it appears the co level actually measures lean as there is unburnt oxygen passed through the engine
So tonight I wound the rev limit up to 9k so as to eliminate it …. Result Is now a stable afr all the way through to 7200rpm . So it seems it was the soft limiter after all.
At least I’ve learnt a lot more about mfi pumps on this particular journey :lol: … along with feeling a bit stupid !
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