Gp1 44idf carb restoration project

[mrwatt]

Sitting in the house with a broken elbow and little finger after a spill on the motorbike so I have time to post up a thread that some folks might be interested in and it might relieve my boredom. The typing might be a bit dodgy with my left hand so bear with me.

This is what they looked like at the start

[thedman]

Got a proper dipstick Neil?

[mrwatt]

Got a proper dipstick Neil?

in time Darren

Next up strip down and see whats required and what 30 years of use has done.




Note cam operated pump rather than rod operated later types

[mrwatt]

Check out the throttle pulley OMG

[mrwatt]

Ok stripped down for blasting and repair. some bungs and plates made to stop any glass beads entering the internals.

[mrwatt]

Spindle removed from the 2nd carb shows that the lever link has been brazed on !
Don't know if this is original or a bodge, I think the latter.
The reality is that the bearing cant be replaced without removing it.


I don't fancy rebrazing this after new bearings are fitted as it will destroy them, probably why the originals were seized.

And the 1st carb has a pressed washer on preventing easy bearing replacement. Bearing is well past it as you can see.


So as replacement spindle shafts for 71 IDFs are available with threads on both ends it was looking like the way forward.

[mrwatt]

Whilst inspecting the component parts found that all 4 pump jets had been crushed at some point probably in an attempt to reduced fuel flow.


These are available so 4 new ones ordered.

[mrwatt]

Meantime a Genuine FORD Inlet manifold appeared on ebay, so bidding commenced and was won , time to open wallet again Turned out to be a nice unwelded manifold, unusual for ebay purchases these days

Bead blasted with honite glass beads.


Looking for a vacuum 90 degree take off if anyone has one. Bolt is temporary

[Paulk RS1800]

When you get the carbs back after been blasted you should bond the extra holes in the carbs that are blanked off with lead. One of the lead blanking plugs fell out of idfs on my car and sprayed petrol all over the engine bay, I was very lucky car did not go on fire. Paul

[Andyc]

Neil,
I will send you my 45s when you have finshed these if thats ok.

Mend soon mate, its not nice a broken elbow, I did mine about 4 years ago chasing a egg shaped ball

[mrwatt]

When you get the carbs back after been blasted you should bond the extra holes in the carbs that are blanked off with lead. One of the lead blanking plugs fell out of idfs on my car and sprayed petrol all over the engine bay, I was very lucky car did not go on fire. Paul

Thanks for the heads up, I have removed 1 dodgy one and blanked it already.

Neil,
I will send you my 45s when you have finshed these if thats ok.

Mend soon mate, its not nice a broken elbow, I did mine about 4 years ago chasing a egg shaped ball

All should be good in a few weeks

Cheers Neil

[mrwatt]

Linkage removed from shaft, was to short anyway so time to replicate it in stainless steel. Had to straighten out with heat for a pattern

[mrwatt]

New shafts don't come with the pump cam roll pin holes drilled so it up to you to drill them.
This has to be done accurately as it determines when the cam starts lifting the pump rod, also both carbs have to work at the same time for correct synchronisation.

This picture shows me checking the old shaft first and the new shaft on the Milling machine bed.



No second chances , new shaft drilled below


you might be able to see that the hole is off centre and angled in relation to the butterfly plate.

[mrwatt]

Blasted and mocked up together, still got shafts and linkage to do

[mrwatt]

Need new meshes for the cold start


Stainless mesh is what I had lying around