Hey, I wanted to share some photos and details for a project I finished up awhile back for a customer. It is one of the best looking transmissions I have done so far!

Click to view attachment

Click to view attachment

Click to view attachment

Click to view attachment

Click to view attachment

The transmission is going into a 550 Spyder kit car. Initially the customer was looking to use a type 902 transmission (out of an early 912) that he had on hand, and it would be using a cable shift setup designed for the 911 style tail-shift. But due to various difficulties with the 902, we decided to instead to use a tail shift type 914 as the basis and then make some modifications to match his cable shifter setup. It still is a tail shifter, but it now uses the magnesium tail and shift rod from a 911 instead of the 914 setup. It is very much like the magnesium case type 911 transmission (used by the 911 just prior to moving to the type 915 transmission), but setup in mid-engine configuration. There are some other tweaks such as the 911 style fill drain plugs, some replating of parts as well as the fact that it is painted!

Even before I started doing transmission rebuilds I have been researching and experimenting with different ways to protect cast magnesium parts. While the factory says to use Tectyl (and it is good stuff), it doesn’t provide long term protection as it has to be periodically reapplied. There are lots of opinions on how and what to use to paint a transmission. My criteria was a high temp paint, preferably not rattle can, ideally a two part paint system and something that cleaned up well once in the car. I ended up using Eastwoods high temperature ceramic engine paint. I like it because it is high temp (transmissions do get hot), works well with a urethane activator, sprays on great with a regular gun (I use a HVLP detail gun) and looks awesome! The paint is also formulated to be shot directly onto bare metal. Eastwood offers a number of different colors, but this is their "Aluminum".

The case was first chemically cleaned, glass bead blasted (exterior only and not on the mating surfaces) and then washed inside and out again (I expect I will get questions about the bead blasting process). As with any paint job, the prep work is what takes all of the time. It’s not easy to get all of the oil, grease, etc. out of all of those deep nooks and crannies. It’s a lot of work to clean a transmission case!

I am having a rough time figuring out how to price this for regular customers. I may have to price this on a per client basis, but I am curious as to what you people think would be a fair extra charge for this type of paint job when rebuilding a transmission? I would really like to put a standard price on this service. How much would you pay for this?

Richard

seems to me you got to price it based on labor hours and materials.

sure looks sweet.

now you should be prepared for question about transaxle oil temps : )

jim

It sure does look good. I have no idea so I will just throw out $200.

David

Yeah, the entire "paint or not" debate and "traps heat" can be a bit of a religious debate. At a minimum I am sure it cast off heat better than a transmission covered in a 1/4" layer of 40 year old grease, oil, dirt, grit, bugs, etc. which is how most have been treated their entire life.

Richard

Very nice! Considering it's going into a 550, I can see why they want it to look nice.

Do you have to clean transmission cases by hand? If you know someone in your area who has one of these, you might be golden. (Or you could ship to McMark, depending...)

McMark's parts washer

Thanks! He still has a way to go on the 550, but he is going to send photos when he gets it installed.

Regarding the cleaning. I have a local machine shop that I use that uses something pretty much like what McMark has. It work really well, but some of the baked on stuff needs some manual attention. Brake cleaner and a dental pick works wonders. It is also a pain that the way the cases were cast in that they are not 100% smooth. So you can have stuff trapped in small pores or on rough raised areas that are left over from the casting. In the pictures above it looks like large chunks of dust on the bellhousing, but that is just the roughness left over from the casting. I could polish some of that down, but it's a slippery slope. Before you know it you could have many many hours invested in cleaning. The more you clean the more you find areas that you can improve upon. At some point you just have to say "this is good enough".

I can't afford it, but I would love to have a large ultrasonic cleaner. My degree is in Electrical Engineering and I have considered building my own. Power amplifier, waveform generator, ultrasonic transducer, large tank of solvent, etc. If I have time I may give that a go sometime this coming year.

Richard

That looks sweet! I was thinking something between $200 and $250.

wow. that is show car worthy . I hope it stays that clean for a long time.

trans temps can easily go past 250 deg f

That looks great, FYI, have you thought of using a thermal disperent on the exterrior?

A little. Its highly likely that over time I will continue to try out new things. I know there are a number of things like thermal dispersents that are usually available via places that do specialized coatings. I would love to find something that I can do myself. If anyone has any suggestions, please feel free to shoot them my way!

I also would like to play around with colors. You have the entire "black body" thing and that I could be using a darker paint in an attempt to help radiation. One of my concerns is that will the transmission be the hot (net looser) or cool (net gainer) item in this scenario? I would hate to turn the transmission into a heat sink that might absorb more heat from things such as the exhaust system, oil coolers, and the engine itself! I would love to hear opinions on this one way or another.

Richard