omgpham…
25May/120

ITB Assembly

The enamel paint on the ITBs finally dried, didn't air dry in 7-days like the instructions said. And I actually had it in the oven for a total of 12-hours at 60degrees. That was annoying...

Anyway, I had some time today so I went for a drive in search for new throttle plate screws. The factory screws are M3 which are "mushroomed" from factory to stop them from ever backing out. I drilled these out so I could pull apart the throttle bodies for sand-blasting and paint. Checkout the photos here - http://omgpham.com/itb-strip-clean.

Follow on after the break to check out more photos.

Read more after the break...

The shop is called Small Parts & Bearings, they stock a huge range of screws and taps. Had a chat with them at the shop and they recommended the M3.5x0.6 Hex Cap screws. I bought the required tap too, total was $18. Not too bad I thought.


First step was to drill out the hole slightly and then tap the new thread.


Just test fitting the new screws, had to cut/shorten the screw too.


The assembly station, used a syringe to apply oil in the tight spots. Also picked up some spare ITBs for parts, was great having them there so I could check how everything went back together.


One throttle body done, three more to go.


All four throttle bodies assembled!

This next part is a bit hard to explain, but basically the Toyota throttle linkages don't really match up with the stock Mazda throttle cable. There's a bit of slack as well as not enough travel in the throttle pulley. The idea is to make more space between the throttle cable stop and the throttle linkages, this removes any slack in the cable. It's quite straight forward to do, just have to move some parts around so that the throttle linkages sit on cylinder #3 and #4 instead of #2 and #3.

After re-assembling the throttle bodies, the service manual outlines the procedures to adjust all four linkages that "daisy-chain" the throttle bodies together. I'll do that in the next couple of days hopefully.


I can't wait to get these on the car!