Intake horn corrosion

[secondchance]

I always thought the LT5 under the hood was the prettiest part of a ZR-1. Being a daily driver, after 14 years, motor is beginning to look a bit messy. So, I am thinking about refinishing valve cover and intake plenum/horn - either Ligenfelter paint or powder coating.
I would love to solve corrosion issue (adjacent to cover plate on top of throttle body) before refinishing.
It seems different metal and presence of current is causing this. One thought I had was figuring out a way to insulate 3 electrical pieces connected to throttle body/air horn:
1. IAT sensor - simply relocate to plastic air intake above air filter housing.
2. Throttle position sensor - I got to disassemble and figure out.
3. IAC motor - Insulate bolt from bracket.

Has anyone figured out how to stop this corrosion?

Another thought is to purchase "Counter Act" electronic corrosion control unit and apply the patch to underside of throttle body. However, heat may make this impractical.

Any thought or info would be appreciated.

[GOLDCYLON]

Well im not sure how to stop the corrosion however The old paint was not that durable on our motors from the factory. For PCing I recommend Jeffvete a forum member here who did the PCing on my car. He could have your plenum, Cam covers and Airhorn seen to in no time.

Heres a couple of Photos of Jeffvettes work. I took these about a year ago still need to snap a few with the Samcos upgrade.

http://members.cox.net/goldcylon/ENGINEAIR.JPG

http://members.cox.net/goldcylon/ENGINEAIR2.JPG

[QB93Z]

I will offer a cople of suggestions:

There is a vendor on the Net/Registry web site that sells an aluminum Throttle Body cover plate that is engraved with ZR-1. That plate being aluminum should not cause a galvanic corrosion problem, which is what i think you are talking about. There are a lot of other components connected to the throttle body that are dissimilar metals that can not be removed. If you keep the area clean and dry, the corrosion should not be a problem.

The part you refered to as a valve cover is called the cam cover. There is a lot more to it mechanically that just a valve cover on a standard V-8.

Once you start powder coating or painting engine components, you will end up wanting to do all the top-end components, because the newly finnished parts will stand out against the old pieces.

Jim

[flyin ryan]

Jim is 100% regarding dissimilar metals/alloys. i've never mentioned it but have thought in the past about trying metallic ceramic coating. more commonly known as header coating. it's tuff stuff.

[secondchance]

Thanks to all of you for your input.
Also, I notice coolant in/out tube for heating the throttle body during warm-up. Does coolant flow below the plate? I was thinking coolant possibily acting as electrolyte.

Also, I didn't know the plate was non-aluminum. Perhaps replacing the plate is the solution.

Thanks again!

[PhillipsLT5]

Bypass coolant

[flyin ryan]

Jim is 100% regarding dissimilar metals/alloys. i've never mentioned it but have thought in the past about trying metallic ceramic coating. more commonly known as header coating. it's tuff stuff.sorry, i guess i should have been a little more clear. when i'm talking about using ceramic metallic, i, myself, would only do the inside surfaces. want to try keeping the outside relatively factory looking. maybe not on my serious engine, but on these ones anyhow.

[QB93Z]

Thanks to all of you for your input.
Also, I notice coolant in/out tube for heating the throttle body during warm-up. Does coolant flow below the plate? I was thinking coolant possibily acting as electrolyte.

Also, I didn't know the plate was non-aluminum. Perhaps replacing the plate is the solution.

Thanks again!

I believe that the original equipment throttle body plate is aluminum. I was referring to the plate shown in GoldCylon's pictures, it is aluminum also.

I don't think you need to be concerned about galvanic corrosion because of the coolant in the throttle body. If it was occurring, it would have to be on the wetted surfaces of the coolant passages, not on the exterior surfaces. (Provided the engine surfaces are clean and dry.)

Still, coolant bypass modification may make sense for other reasons such as easier maintenance and possibly performance improvement due to cooler (denser) air charge.

From what I have learned about the LT5, the biggest causes of stained or darkened engine surfaces are stains from spills of engine fluids and inappropriate cleaning solutions.

Jim

[secondchance]

I believe that the original equipment throttle body plate is aluminum. I was referring to the plate shown in GoldCylon's pictures, it is aluminum also.

I don't think you need to be concerned about galvanic corrosion because of the coolant in the throttle body. If it was occurring, it would have to be on the wetted surfaces of the coolant passages, not on the exterior surfaces. (Provided the engine surfaces are clean and dry.)

Still, coolant bypass modification may make sense for other reasons such as easier maintenance and possibly performance improvement due to cooler (denser) air charge.

From what I have learned about the LT5, the biggest causes of stained or darkened engine surfaces are stains from spills of engine fluids and inappropriate cleaning solutions.

Jim

For sure. But over a period of time, inevitably stain accumulate, especially when driven everyday.

[tomtom72]

I would just offer up this suggestion concerning that corrosion on the T/B cover plate.

Upon dissassembly use some baking soda solution or white vinegar and a very stiff tooth brush on the bare metal gasket lands in that coolant cavity. I had to spend a good bit of time to remove all the white looking residue from those areas using even a brass bristle brush (gently) and a tooth brush, using the vinegar as a lube & cleaner. I even used some crocrous cloth wetted with paint thinner and eventually I got it all off of all the surfaces, the gasket lands, coolant cavity & plate, screw threads and screw holes clean. I wonder if CLR would be the best thing to use???

Anyway, after cleaning I then washed all the fromerly corroded surfaces w/steam distilled water & dish soap and then rinsed and used acetone as a final de-watering wipe. I used the LPE paint to refinish my stuff. I also didn't have any pock-marks than required any body work to make smooth.

I didn't paint the gasket lands, I masked them off on the T/B and the cover plate I only painted the top side. I used rtv to coat the gasket on both sides and reassembled. It's been since October of '05 and I haven't had the corrosion come back....but I do use steam distilled water to mix down my coolant and it gets done every two yrs without fail.:dontknow:

:cheers:
Tom

[flyin ryan]

I would just offer up this suggestion concerning that corrosion on the T/B cover plate.

Upon dissassembly use some baking soda solution or white vinegar and a very stiff tooth brush on the bare metal gasket lands in that coolant cavity. I had to spend a good bit of time to remove all the white looking residue from those areas using even a brass bristle brush (gently) and a tooth brush, using the vinegar as a lube & cleaner. I even used some crocrous cloth wetted with paint thinner and eventually I got it all off of all the surfaces, the gasket lands, coolant cavity & plate, screw threads and screw holes clean. I wonder if CLR would be the best thing to use???

Anyway, after cleaning I then washed all the fromerly corroded surfaces w/steam distilled water & dish soap and then rinsed and used acetone as a final de-watering wipe. I used the LPE paint to refinish my stuff. I also didn't have any pock-marks than required any body work to make smooth.

I didn't paint the gasket lands, I masked them off on the T/B and the cover plate I only painted the top side. I used rtv to coat the gasket on both sides and reassembled. It's been since October of '05 and I haven't had the corrosion come back....but I do use steam distilled water to mix down my coolant and it gets done every two yrs without fail.:dontknow:

:cheers:
Tomi think i recall you posting this some time ago? good tips for everyone.

[Chris_32212]

Well im not sure how to stop the corrosion however The old paint was not that durable on our motors from the factory. For PCing I recommend Jeffvete a forum member here who did the PCing on my car. He could have your plenum, Cam covers and Airhorn seen to in no time.

Heres a couple of Photos of Jeffvettes work. I took these about a year ago still need to snap a few with the Samcos upgrade.

http://members.cox.net/goldcylon/ENGINEAIR.JPG

http://members.cox.net/goldcylon/ENGINEAIR2.JPG

what air intake box is this? does it help with power? is it still available? somone mentioned a reverse air cleaner but i have never seen one. does anyone know if they are still available?

Chris

[tomtom72]

Chris that's a "cut lid" type. I do believe over at the NetRegistry site in the vendor section you can find it. If I remember right Mark Copeland sells it, but don't quote me on that. Or you could go buy an air box at a salvage yard and cut the top out yourself and then paint it or do a powder coat job.:cheers:

Thanks Ryan....if I was thinking I would have just posted a link to the thread where it was....:redface:

One of the keys with that bubbling I think is that tap water is the culprit. To cure it ya gotta get all the residue off of the metal before ya refinish it. Then ya gotta use steam distilled water going foreward to eliminate the disolved mineral in tap water. Reason for the SD water is so that the stray electric current does not make salts out of the disolved minerals. JMHO....:o

:cheers:

[Chris_32212]

Chris that's a "cut lid" type. I do believe over at the NetRegistry site in the vendor section you can find it. If I remember right Mark Copeland sells it, but don't quote me on that. Or you could go buy an air box at a salvage yard and cut the top out yourself and then paint it or do a powder coat job.:cheers:

Thanks Ryan....if I was thinking I would have just posted a link to the thread where it was....:redface:

One of the keys with that bubbling I think is that tap water is the culprit. To cure it ya gotta get all the residue off of the metal before ya refinish it. Then ya gotta use steam distilled water going foreward to eliminate the disolved mineral in tap water. Reason for the SD water is so that the stray electric current does not make salts out of the disolved minerals. JMHO....:o

:cheers:

i dont understand what you mean by "cut lid type" ....i have a modified air lid but thats just the part that surounds the filter. the air box on this car looks very different from the one i have on my 93.

Chris

[tomtom72]

sorry Chris, I should have been more specific.

I do believe that the one pictured is sold as a complete assembly by Mark Copeland(?).

My alternative to buying a Mark Copeland unit would be to cut the slatted portion (the top) of a stock lid out to expose the A/F element completely.

I believe that the "mod" to our air boxes is in the How To section at the NetReg site....the home made version will not look as good as Mark's unit, but it'll do the same thing.

I hope I'm being clearer now? Sorry.:o

:cheers:
Tom

[secondchance]

Well, thanks for all the info guys.
I have never removed the plate above the throttle body but from what i read it seems there is a coolant below the plate possibly acting as electrolyte.
Looks like this will be a perfect Christmas time project.

Thanks all!

[-=Jeff=-]

what air intake box is this? does it help with power? is it still available? somone mentioned a reverse air cleaner but i have never seen one. does anyone know if they are still available?

Chris


The one GC has is the the Copland air intake.. it is no longer being made or sold. so you need to find one used.

[GOLDCYLON]

Yep its a Marc Coplan Air blaster he only made about 20 or so and they are NLA. You can still find his inserts for the intake duct from time to time. Very smooth surfaces and indeed an open air element. As stated the closest to it would to be a cut top stock airbox.

[Jim Nolan]

FYI! I was not able to find the new gasket for that plate when I pulled mine. I wound up buying gasket material and making my own.

[Chris_32212]

thanks for the info about the copland unit being NLA. like i said, i already have a modified air lid which exposes the Air Filter element much better than stock so i guess im as good as im going to get there but does anybody know anything about the reverse flow air cleaner? TPIS used to make one but they no longer do, does anybody know if there are any still available anywhere? i was told a guy swaped out to the reverse flow cleaner inbetween runs and picked up 2 tenths in the 1/4. any help is appreciated. again, sorry for hijacking the thread. i really need to stop making a habbit of this. lol.

Chris