Lucas Pi throttle bodies

Lucas Pi throttle bodies

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Discussion

tapkaJohnD

Original Poster:

1,941 posts

204 months

Friday 11th November 2016
quotequote all
Lucas Pi fuel injection uses twin throat throttle bodies, with a butterfly in each, mounted on one shaft.
The shaft is brass (coloured, anyway) and runs in drillings in the aluminium alloy bodies.

Twice now, I've had the front body butterflies seize wide open, which of course locks the other four ditto.
Both times it was the central drilling, between the throats.
Not nice, scary, even if the problem is solvable by turning off the ignition.

I just changed the butterfly shaft the first time, but this time, I want to do something to prevent this happening again.
Bushes in the body drillings? What material? Suppliers?

Glad for ideas.
JOhn

garagewidow

1,502 posts

170 months

Saturday 12th November 2016
quotequote all
the trouble is there are 3 points of contact on the shaft,which increases the likelihood of a shaft seizure.
you may be able to get the central drilling machined slightly larger to prevent this happening.
but I did install bronze bushes in mine and machined new butterfly shafts out of stainless steel purely to make a different throttle operating arrangement and make it easier to calibrate them all.