TB removal and then some!!!

[GOLDCYLON]

Originally Posted by Roadster

Oh i always feel comfortable, lol, but with my luck you never know what is going to happen next....the stories i could tell....lol
We did the stainless on the plenum when we did the pull, except one got lost in never never land....but will check into the others.....

Sent from my SM-G935P using ZR-1 Net Registry mobile app

I noticed that. Jerry has all those stainless bolts ready to buy

[Roadster]

I imagine that everyone else is having the same problem with the forum. Don't know what I did, but I may be able to post......lol

Originally Posted by secondchance

Tom,

First, your erratic idle rpm may be due to intermittent vacuum leak.
As for the TB corrosion, this is caused by galvanic corrosion - electric current plus steel bolt and aluminum TB, both exposed to water base coolant. Even if refinished will return unless the cause is resolved. In my case, bypassing coolant through TB, was the fix.

Yun,
I found the problem apparently the smoke test was correct. I don't think I have an intermittent vacuum leak, rather it is indeed the primary blade. The TB bypass may be an option for me in the future...I will probably need your expertize for that mod as I know you have something different that you do from reading previous threads.

Did the light test recommended by G8nightman (George) with a flashlight shining through the throttle body blades. I can tell you when you turn out the lights in the garage, it gets dark real quick!!!
But the results are in and correct. When shinning the light through each secondary blade, there is no light what-so-ever coming through. When holding the light up to the primary blade from the back, you can see a good amount of light and also see how far the blade is open. I would venture to say that is my idle problem, no doubt.
Thanks George for the tip and btw, your PM box was fill as of early this AM.
Here are the pics....
light through the primary blade...

light turned off...see what I mean about it being dark.....

flashlight back on....


Now I have to decide and figure out the correct way to accomplish the task. I am not touching the secondary blades, except for a light clean up...hmmmm
maybe not!!!
Have to determine if both the min air adjustment procedure from Dominic and the application of the dry lube will correct the problem. Or just try to adjust the idle stop screw as it is in its present state, and also add the dry lube to help seal the perimeter of the primary blade.

Also looks like I need to sand the TB as some of the finish has cracked off and the top is bubbled, so it needs a refinish. Just might attempt to do it all in the engine compartment and not remove the throttle cable at all.

Originally Posted by GOLDCYLON

I noticed that. Jerry has all those stainless bolts ready to buy

Yes, for sure....that is where the first batch came from....

[Jagdpanzer]

Tom,
Thanks for sharing with the group. Here are a couple of photos of the difficult to adjust Allen set screw exchanged for a M5 x 0.8 25mm cap screw and full size nut. If you do this mod be sure to massage the contact end like shown in the bottom photo.

[XfireZ51]

Gap on the primary certainly looks greater than .002".

[Jagdpanzer]

In my experience when using a bright light the opening clearance appears much bigger than it actually is when measured with a feeler gauge.

[XfireZ51]

Originally Posted by Jagdpanzer

In my experience when using a bright light the opening clearance appears much bigger than it actually is when measured with a feeler gauge.

phil,

I understand what ur saying but that still looks bigger than the thickness of a paper strip. Due to the contour of the bore, I don't rely on a feeler gauge. A paper strip gets it close as a start.

[carter200]

Need an engraved billet throttle body plate to clean things up.

[Roadster]

Originally Posted by Jagdpanzer

In my experience when using a bright light the opening clearance appears much bigger than it actually is when measured with a feeler gauge.

Originally Posted by XfireZ51

phil,

I understand what ur saying but that still looks bigger than the thickness of a paper strip. Due to the contour of the bore, I don't rely on a feeler gauge. A paper strip gets it close as a start.

Did the paper strip test as posted in the other thread, but would like to know how much of an opening it really is...

Originally Posted by carter200

Need an engraved billet throttle body plate to clean things up.

Sounds good to me, what are the choices???

[carter200]

You've seen my billet throttle body plates on many, many Z here and in the newsletter in my sponsor section. Email me if you have ideas for something else.

[XfireZ51]

Originally Posted by Roadster

Did the paper strip test as posted in the other thread, but would like to know how much of an opening it really is...

The paper strip is about .002". Its a place to start not a final. That will be based on IAC counts and desired idle rpm. The paper should have a slight drag to it.