Throttle Body Corrosion Repaint

[Socalerv]

Originally Posted by tomtom72

Get another plate from Carter. They are pure ZR-1 jewelery!!!! Your girl will love you for it too!


Sorry for the shameless plug for Carter, but he does the sweetest machine work this side of Mars! Oh, Hi Carter!

If you want to stop the corrosion and retain the coolant flow you need to get rid of all the white powdery stuff. I used a brass brush + WD40 for most of it. Then I used acetone + paper towels. Then I used 1000 wet to make nice nice. Then, and I think this is the important part after removing all the white stuff & the pox marks. You have to coat the new gasket on all sides and the holes for the screws. Reason is to insulate the two metal parts and the screws from the coolant. It's electrolysis that causes the pox. Two dissimilar metals in contact with water ( coolant ) and in the presence of an electric current ( block is ground ). If you interrupt that circuit you're good to go. I did that to mine back in 05 when I did my injectors and it hasn't been back since!

Have a new plate coming from Carter. Coat the new gasket with what?

[secondchance]

Originally Posted by tomtom72

You have to coat the new gasket on all sides and the holes for the screws. Reason is to insulate the two metal parts and the screws from the coolant. It's electrolysis that causes the pox. Two dissimilar metals in contact with water ( coolant ) and in the presence of an electric current ( block is ground ). If you interrupt that circuit you're good to go. I did that to mine back in 05 when I did my injectors and it hasn't been back since!

I agree w/ you Tom. I figured when the paper gasket gets wet and when it doe it will allow the current to flow between the throttle body and the plate. I think the steel bolts against the aluminum throttle body and the plate has something to do with it also.
When I removed the plate I noticed the OEM paper gasket had been soaked for a long time and sort of crumbled.

[secondchance]

Socalerv,

When I did this I could not find any paint to match the facory finish which had turned dark. I ended up using Duplicolr VHT silver, black, primer (to reduce metallic effect) and a dash of metallic champagne to match the finish and used a Badger air brush. After the air brushing, used VHT clear lightly (heavy coat would turn it too glossy) to seal the finish. After 2 years it looks similar to naturally aged factory finish minus the stains.

[Z51JEFF]

Originally Posted by Socalerv

Was the plate stuck, or bolts seized or both??

Thought of soaking with PB or WD40 before I attempt the removal. Probably get another plate from Carter.

Th plate was stuck,glued to the gasket.

[Socalerv]

Originally Posted by secondchance

I agree w/ you Tom. I figured when the paper gasket gets wet and when it doe it will allow the current to flow between the throttle body and the plate. I think the steel bolts against the aluminum throttle body and the plate has something to do with it also.
When I removed the plate I noticed the OEM paper gasket had been soaked for a long time and sort of crumbled.

Have a gasket coming from Jerry's. Coat the gasket with what to stop the problem.

[secondchance]

Originally Posted by Socalerv

Have a gasket coming from Jerry's. Coat the gasket with what to stop the problem.

After applying the gasket w/ high temp silicone on both sides, laid the gasket on the throttle body, put a coat of sealant around the edge before bolting the plate and let it set over night before starting the car.

[Socalerv]

Originally Posted by Paul Workman

Two ways to do it: the bypass or plugging. Either will work, but plugging allows you to remove some plumbing, and bypassing can be done without removing the plenum.

Bypass:

Remove the two curved rubber hoses that lead to the TB from connections on the plenum, and replace the two short tubes with a longer piece to connect the two plenum connections together. (The driver's side is a small elbow pipe between the #1 & 3 cylinder runners. The passenger side is a "T" connection.)

As for routing, some route the hose out and under the plenum, attaching it to the coolant cross-over pipe that is there. Or, some run a rubber hose under the plenum to connect the two IH connections together. Either will work.

__________________

Plugging off the coolant passage:

This requires removing the plenum to access the little coolant passages in the IHs that route coolant up through the plenum (to the afore mentioned connections). Drill and tap the holes and place an aluminum pipe plug, wrapped with Teflon tape.

Mine happens to be brass (aluminum would be better in the long run). Anyway, you can see the hex-hole'ed plug in my IH. That's there to shut off the coolant to the TB (one on each IH).



There is a line on the passenger side that comes up from the reserve tank area, runs along the plenum rail to the "T" connection on the passenger side of the plenum. Follow that rubber line back under the reserve coolant tank area, cut it and plug the hose (I used a metal shank from a bolt, wrapping the hose with a worm-type hose clamp and tie-wrapped it out of sight.) Remove the excess plumbing...OR DON"T! (I left the plumbing in place - gives the the motor more of a stock look. The choice is yours.).

A couple nice benefits for cutting off the coolant to the TB, in addition to the corrosion problem:

1. The plenum runs significantly cooler! Not a bad thing when trimming 1/10ths of your ET.
2. It can be argued too that the cooler temps could prolong the life of the DIS module (fastened to the plenum). Certainly won't do it any harm not to run so hot.
3. You never have to fuss with draining and re-filling the coolant before removing the plenum. It cuts considerable fussing around off, next time you need to get under the plenum for something. (AND, there WILL be another time...trust me)

Hope this helps.

Oh, if your wondering about the runner diameters being uniform, instead of the primary being smaller, it is because mine has the "FBI 500" package applied to it. hence the uniformity of the runner diameters.

P.

Just to keep it simple for me what size of tap kit would I need?

[Paul Workman]

Originally Posted by Socalerv

Just to keep it simple for me what size of tap kit would I need?

The plug size isn't critical. It just has to be slightly bigger than the hole it has to plug. (if memory serves, mine was a 3/8", or about that size).

So, measure the hole, find the plug that is just slightly bigger, and then look for the matching tap. Then get the drill bit size recommended by the thread tap to prep the hole for the tap. (I'd send you mine, but I don't have any spare plugs, and my bit and tap may not match the size plug you might find. Anywayz, I got everything I needed at ACE Hardware.)

P.