Tii Throttle Body Question

[PaulTWinterton]

I've just become aware of the bushing on the shaft of the tii throttle body.

Actually it fell out. Once I re-inserted (loosely) I noticed .5 -1.0mm combined lateral play of the shaft on the inside and outside of the bushing.

Is this bushing available anywhere?

Does someone have some experience fixing this problem?

Or am I hooped and need a new shaft as well?

Any input please.

Thanks,

Paul Winterton

Vancouver, BC

73 Ikca tii #2762958

[bnam]

Paul,

Remove the throttle shaft from the housing and look for wear on the shaft.

I'd expect the bushing itself is repairable by a machine shop or carb rebuild service or DIY.

The wear on the shaft could be trickier. I ended up getting a good used throttle body from Rob. The shaft on the one that was originally in my car had worn an appreciable groove. This photo does not show the groove clearly enough, but it allowed about 0.5-1mm of radial play.

I have considered fixing the groove by welding it and grinding down or using metal epoxy paste to fill the groove. I will probably try the latter.

If you can fix or get fixed the bushing, I suggest you try the epoxy fix first and if that does not hold up, buy a used one (you have to buy the whole throttle body).

Byas

[PaulTWinterton]

Thanks Byas,

I was afraid you'd say that. My shaft is worn. Maybe not as worn as yours, but still...

All in all, this play is not helping the syncronization of the fuel/air, right?

I'm chasing a lumpy cruise between 2000-3000rpm.

Paul

[NickVyse]

It would be very quick and simple to weld and grind that back to shape, or cut it off, turn 180 degrees and weld back on.

[adawil2002]

That lump you're feeling is where the air/fuel curves are intersecting I've been able to lessen mine @ 2300 by very slightly leaning the mixture.

How are your throttle linkages?

[PaulTWinterton]

Andrew,

I thought my linkages were good, but now this worn spot changes my thinking. Slop on the shaft can't be good.

There should be NO lumpy spots in running performance. I will not accept that. My tii did not have this issue 'once apon a time', so it should be fixable. I had other tii's that never had this issue.

I've been through the process. Ignition, all new. Air hoses and gaskets, all new. Ignition tuned, valve adjustment. Linkage adjustments and replacements. Warm Up Reg tested and adjusted.

I believe this shaft and bushing could help. Will get that fixed for sure.

Paul