Author Topic: Primary /Secondary throttle plates  (Read 2942 times)

Offline renegade

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Primary /Secondary throttle plates
« on: May 16, 2016, 04:54:28 AM »
Ive installed your bushing kit for the primary throttle plates and Im now reassembling the the throttle body.I have reinstalled the primary and secondary throttle plates and put the throttle body up to a light and see light coming in around the circumference of the throttle plates.More so with the secondaries.Im sure Ive reinstalled the plates correctly as each has a bevel to them.I also read part numbers for the secondaries face down and towards the center,primaries up and towards the center. Ive loosened them to try and orientate them better but no real change.How critical is this?
Thanks for any help.

Offline carmantx

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Re: Primary /Secondary throttle plates
« Reply #1 on: May 16, 2016, 10:19:19 AM »
Are you certain the throttle arm is closing all the way? Try disconnecting the secondary shaft.  If these components are not set up correctly, they can prevent the primary from closing properly.
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Offline Cliff Ruggles

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Re: Primary /Secondary throttle plates
« Reply #2 on: May 18, 2016, 01:37:25 AM »
I spend quite a bit of time with these things to make sure the plates are fully seated.  Linkage may need adjusting to allow them to fully close, and you may need to turn the plates slightly to get them to align well and fully seat in the bores.

I use a screwdriver handle to gently tap the plates into the bores and hold it up to the light before tightening the screws.  If the plates are well sealed up, then you see more light after tightening the screws, it may need linkage adjustments as they are pulling the plates open.....Cliff

Offline renegade

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Re: Primary /Secondary throttle plates
« Reply #3 on: May 18, 2016, 04:24:31 AM »
I haven't attached any linkage from primary to secondary so theres nothing to hinder the closing of either primary or secondary throttle plates.The best way to describe the amount of light coming in around the plates is paper thin as Ive closed the plates on a piece of paper and Im able to pull the paper out with a high degree of resistances.Sometimes ripping the paper depending on where I place the it in the bore.It appears as though the plates are egged or not completely round in the bore.I haven't changed anything on the secondary throttle shaft and I did not pay attention during disassembly to the secondary side if there was this light leaking through then.My question is are you saying that the plates should close tightly and there should be no light showing at all?What Im considering is placing a piece of sand paper between the plate and bore,closing the plate on it and dragging it out and bring down the high spot on the plate.

Offline Cliff Ruggles

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Re: Primary /Secondary throttle plates
« Reply #4 on: May 19, 2016, 03:03:29 AM »
There will always be a very small amount of light around the plates, but very little and it should be pretty even on both sides......Cliff

Offline renegade

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Re: Primary /Secondary throttle plates
« Reply #5 on: May 25, 2016, 06:47:34 PM »
Sorry been busy but I did want to say thanks and that Ive installed the carb and fired it up.Seems ok.Tweeking the idle air,idle and choke.