Sticking Butterflies

I'm having an issue with the butterflies sticking on my injector. The injector is a carbon TRP from Australia. It only happens when the engine is running, they are perfectly loose with the engine not running. The gap is at .013. 526 Veney Hemi SSI roots blower. Anyone ever run into this? Its driving me crazy..!


Thanks,
Paul

 

Icing over? Or just getting stuck shut. Have you put the blades at zero and loosened the blades then tightened them up and reset the gap? .013 seems a little tight. Also wd 40 all the bearings and anything that moves between the hat

 

Aluminum throttle shaft ?

 

I had the same issue , the hat wasn't strong enough. The carbon deformed at idle , causing the blades to stick. Worth watching the top of the hat when idling , and then see it rise back to shape when you can crack the throttle.

Worth a look

 

This hat has a stainless steel shaft and a aluminum insert that the butterflies are in. Also I've reset the butterflies twice..

Thanks,
Paul

 

Could be too much vacuum in the injector, you can open the butterflies a bit more or put airvalves in the hat.

 

Some may read this and roll their eyes, but almost every time I've been asked to set up an injector they have been pretty scary.

Disconnect the throttle cable, springs and everything else off the injector shaft but leave the lever arms on. Loosen all of the butterfly mounting screws and back off the adjustment screws that sets the butterfly idle position away from the stops so you can completely shut the injector. With your fingers on the butterflies move them around until they fully seat in the injector housing while rotating the throttle shut. You might need to rotate the butterfly shaft open and shut very slightly to get all of them to seat together. It might take a few minutes to work them tight into the housing. I've seen where the shaft actually moves further shut because one or more of the butterflies were bound up from side to side or vertically when doing this.

Once you are satisfied that every butterfly is fully seated in the housing with the throttle completely shut and not being held open at all by the adjustment screws on the ends, tighten up the butterfly mounting screws. Open the throttle and shut it. It should have a solid click feel and seat all the way back into the same position with no gaps anywhere. With the throttle open you should get a small amount of side to side end play as the butterflies should not be bound up in the housing. This is a good time to check for twist in the butterfly shaft. If the butterflies seat on one side but appear slightly open on the other you can use a throttle arm on each end of the shaft to gently twist it to square it. Loosen the butterfly screws again and try seating them in further, then retighten. You can now remove the butterfly mounting screws one at a time and locktite them in place. At this point you are ready to set your gap. Make sure you set it from both ends of the housing so any pressure to close either side is held against the adjustment screws on both sides. If one side sets wider than the other the shaft may be slightly twisted. Try tweeking the shaft as I said.

Next, check the full throttle stop screws. Open the throttle to the wide open position. Both stop screws should come in contact at full throttle at the same time and not allow any twisting of the shaft. Now hook up your throttle cable. Make sure at wide open throttle the throttle stop on the pedal is actually stopping the throttle and not the stops on the injector. To do this, have someone hold the throttle wide open at the pedal with all your return springs hooked up, then grab the throttle lever arm on the injector on the same side as your throttle cable with your hand and try to rotate it closed. You should be able to move the injector off of full throttle stops with less than medium effort. If you have difficulty moving it off the full throttle stop at the injector you are binding the injector and may actually be bending the injector throttle shaft. Improper full throttle set up is the number one cause for broken throttle cables and joints.

If it still tries to bind up after all this, get a new injector.

Standard disclaimers apply. The advice given is only worth the amount you paid for it.


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