F.I. throttle shaft seals

7982X

7982X

So much fun it MUST be illegal!
I did a search on the workshop forum for a thread concerning removing (& replacing) the throttle shaft seals in the plenum. I didn't find one that specifically dealt with this issue. We are getting our plenum & manifolds ready to have them ceramic coated and as the seals are shot anyway, we need to replace them. It appears that you cannot drive them out from "the other side" as the ID of the metal seal housing isn't much smaller than the hole in the plenum (or the bushing anyway). Does anybody have any words of wisdom (or experience) on how to remove the seal bodies? We have new ones to go back in. I really do not want to damage anything and it looks like that would be fairly easy to do. I have received a couple of thoughts, such as prying them out, drilling them and "hooking" them, using a drift or pin punch, or a small seal puller. We are looking to add as many ideas as we can from an experienced pool to improve our chances of success.
Your input will be appreciated.
 
I removed mine for the same reason (ceramic coating the plenum) several years ago and not certain but think I picked them out using some HF pics. After coating I just carefully tapped the new ones in. I think I got the replacement seals from one of our vendors.

Btw be certain that you properly plug all the small vac line ports on the plenum before coating. My guy missed a few and I had to clean them out afterwards....
 
Have a couple sets of the picks.....amazing how useful they are. Thanks for the tip on plugging the ports as well. I was identifying all ports & surfaces to be masked when I remembered that the seals still needed to be removed. (That's what happens when you do these things over a period of time.....you can forget details.) I had to partially reassemble some things to remember how they fit and what could & couldn't be masked.
Are you happy with the results of ceramic coating your plenum and did you do the manifolds as well? We are also using a coated Allison header, ceramic coated cat & coated dual outlet muffler. They look really nice and hopefully aren't too loud (I outgrew loud exhaust many years ago).
By the way, I really enjoyed your video. It has been a long time since I have driven an X (except to check out the engine in our donor car) and it did my heart good to "experience" it again.
Thanks for your input!
 
I'm pretty happy with the coated plenum. It's shiny, zero maintenance, and looks nice although the polished ones look better (and cost much more to do with add'l upkeep). Here are some before and after pics of mine...
IMAG0033.jpg IMAG0149.jpg IMAG0150.jpg 20170527_115928.jpg
 
WOW, looks pretty darned nice! We have that to look forward to. Did you have any trouble with the ceramic cracking where you bolted on the TPI? I was thinking of masking off those "flats" for fear of the coating cracking under the TPI mount flanges. We are doing the coating as much for helping keep the exhaust heat out of the intake system as for the good looks & low maintenance. Also interested in your custom heat shielding. Is it also between the header/intake manifolds & the fuel rail? I have started to work up a cardboard mock up to do just that but got sidetracked by other things. We are trying to avoid installing a fuel rail cooling fan, kind of preventing the heat problem rather than "fix" it.
 
OK, we got the seals out by "driving" a jewelers screwdriver down along the side of the seals in several places....bending the sides enough to grab them with a needle nose vise grip and pull them out. Not an easy or fun job, but other options did not work for us. We then had the bushings removed by a machine shop. New bushings & seals were purchased from Chris Obert, to be installed after ceramic coating the plenum. Don't ever want to do this again.
 
I have not tried to remove/replace these seals or bushings, so this is just a thought. But consider if the added thickness of the ceramic coating within the bores (where the seals/bushings fit) will change the inner diameter enough to make reinstalling more difficult. It may be another area to mask off? However ceramic is not very thick (like powder coating for example) so this may not be an issue. Hope someone else has direct experience to add.

You asked Geekdaddy: "ceramic coating your plenum and did you do the manifolds as well?" When you say 'manifolds', are you asking if the intake runners from the head to the plenum were coated as well as the plenum? I can't answer for Geekdaddy, but considering reducing heat from the exhaust is your goal, it seems to me coating the runners would be more vital than the plenum...they run directly next to the exhaust where heat transfer would be greatest. Likewise for adding heat shields between the exhaust manifold and the intake manifold (as you already mentioned).

As for potential cracking of the ceramic coating I doubt that should be a concern, it is very strong and the clamping loads are not that high.

Just for thought, on another project vehicle (non-Fiat) I had both the inside and outside of the manifolds ceramic coated. Partially for possible added heat shielding, but also to help keep those inner surfaces clean...preventing build up of any carbon deposits, etc. Honestly I've never had it back apart to look (it was recently done) so I can't testify to the results. And I've read mixed opinions regarding the inner surface texture on intake components; one theory is smooth walls allow for better flow, another theory is a slightly rough finish helps prevent fuel from forming droplets. I won't take sides on that. I really did it because I could (the coating company was using my parts for some testing so it was done for free). We also tested the use of ceramic coating on the inside of fuel tanks to prevent rusting. Which brings up a related comment; there are newer ceramic coat products that do not require the specific heat treating process to cure it, they are "air cured". So these can be done at home yourself. The products are not cheap but should be much less than having the parts done professionally. I have some but haven't tried it yet so can't comment on its worth.
 
Yes, I was referring to the intake runners when I said manifolds.
We plan to have the bores for the throttle shaft seals & bushings masked and the threaded holes, and the insides as well. The coater suggested coating the stud threads, saying that it doesn't interfere with the fasteners. They also recommended coating the mount flanges as well. The plenum will be coated much like Geek Daddy's plenum (they call it chromex), and the intake manifolds will be coated a dull silver, but a material that is a bit better than the chromex for blocking heat. We are also planning on asking the coater about coating or masking the areas where the injectors seal to the intake runners. Coating the insides is an interesting thought that we hadn't considered and we may ask the coater their experience with that.
The total quote for all of this is $315.00 and they are relatively local (70 miles away). Nice that you were able to get your parts done as part of a "cooperative venture" VS full price.
I haven't figured out all of the heat shielding yet, but am thinking of a formed sheet metal shield as well as an insulating sleeving over the fuel rails. The stuff I have used on other projects is similar to split wire loom, but heavier and with a foil & fiber insulation over it.
As far as the products that you mentioned, not needing heat to cure....we did a set of header pipes for a vintage Triumph motorcycle, coating the inside to help keep the chrome on the outside from turning blue and it seemed to help. I have not thought about that since, but will keep it in mind for future applications.
 
Good to know the studs can be coated without ruining the threads; the coating is very thin so that makes sense. That being the case, you could likely coat inside the seal bores without changing the fit of the seals. Same with the injector seals and other holes.
There are different ceramic coating products with varying properties, as well as numerous color choices. But often the difference between the shiny 'chrome' finish and the dull silver is not the material itself; the same coating starts out dull and they polish it to achieve the shiny 'chrome' look. However your place may actually be using two different products.
Just for reference take a look at the "air cure" ceramic coating I mentioned (link below). It's not the 'header paint' or other 'high temp' products often seen. This is a hard, genuine ceramic coating very similar to the one you are having done. Fairly affordable too (compared to having it done). Maybe its what you used on the bike exhaust? You can read about the process and other details here (see the 'high temperature air cure' section):
https://www.cerakotehightemp.com/finishes/

Regarding heat shields, I'm going to try using a sheet of the semi-rigid stuff. It's got multi layers of thin aluminum and a heat barrier material stamped together, with kind of a waffle pattern. Its soft enough to bend and shape but rigid enough to stay in place and be durable. I'd have to do some research to remember who makes it or where to get it but it looks like this:
images.jpg
 
Thanks for the photo of the material. We were going to use stainless, but may look for that material as an option. Looking at the link you sent, the Cerakote name looks familiar, but we did the Triumph header pipes so long ago (20+ years), I cannot remember. I remember that it was chalky looking white stuff that you just poured into the pipe (with the other end capped off) and just moved the pipe back & forth, up & down, and all around to cover the whole inside, then poured out the excess and let it air dry.
We will likely try to keep the bushing/seal bores clean of material as it may be a real pain to clean it out if it is too thick.
My understanding was that the material for the inlet runners was different, but will check with them. My understanding may be that I didn't listen too well when they explained it.!
 
We just got our parts back from the coater and they used Cerakote products. The plenum is Chromex and the intake runners are Glacier silver. They said that the two are different materials, but both ceramic coatings. The Glacier is a bit better at thermal blocking.
 
Thanks for the feedback.
Cerakote makes very good products. Owner is a young guy, really nice to deal with. Their products were originally developed for coating firearms. Now they have several different formulas for various applications. Starting as a small "garage" operation, they've grown with one of the most extensive lines in the industry.
Just curious, what did your coating place say about doing the inside surfaces?
 
We didn't even discuss that option. I just opted to keep it on the outside for now. I am interested to hear what your opinion is on your stuff that was coated on the inside after you have had time to see the results, and have formed an opinion. Ours won't be on the road for awhile yet, so I won't have an opinion for some time. Many other things to do, but at least we can start putting the F.I. together again.
 
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