New 13BT upper thermostat housing 16331-58030 interest?

Joined
Aug 9, 2012
Messages
228
Location
Dallas, TX
So my thermostat housing, both upper and lower, was corroded all to hell. Thankfully the lower housing is still available (though you will need a plug 90341-12006 for an extra hole), the upper...not so much and mine does not have a long life ahead of it.

Rather than kludging together a solution, I got a bug up my ass and decided to see if I could make a CAD design that I could 3D print or have produced. 3D printing would be cheaper for a couple of pieces, but the thermal resilience of the part makes that a little more difficult.

I've made the CAD model. I had the base printed and am waiting to receive it to test fit it to my old lower housing. Once I've made sure I have the base dimensions correct I'll do a complete prototype unit (will need to have small hose outlets tapped for NPT-ends of hose barbs).

These are the options I came up with:
  • 3D printed plastic - ~$50-150/pc depending on volume
    • There are some ABS variants that can easily handle the heat (some new t-stat housings are all ABS plastic now) but the only ones I've found available for 3D printing have a melting point of 112 C which means it would be really close to failure if you ever overheated a little - not a safety margin I'm super comfortable with. I haven't reached out to any printing companies yet to see if they have any new materials not listed in their auto-quote feature but will in the future.
    • Probably the best option if it winds up just being me or a few others and we can find a good heat tolerant material.
  • 3D printed aluminum or stainless - ~$200-400/pc (Al) to over $1000 (SS)
    • Obviously cost prohibitive.
    • At this price CNC/billet machining is probably a better option I have not generated any quotes yet.
  • Injection mold - Probably the cheapest (by far) if there's a large enough group of people interested. I found low volume runs in the 25 pcs range, but I haven't generated a quote yet.
  • CNC/Billet - $$$ not sure how much though. Haven't quoted this one.
It's probably also worth checking to see if a local company would do a small run CNC or injection mold but I'm waiting until I know I have the design down and to see if there's anyone else interested to do that.

I'm sure there's probably an easy fix I missed when I was looking up solutions to my corroded upper housing, but this was a fun way to learn CAD and photogrammetry. Also, I've always been interested in its application for hard-to-find parts and with more and more pieces falling off the radar we may need to rely more on this technology to keep our rigs running and leak proof in the future.

So, if you're still reading, is there any interest in doing a group buy of this? Assuming I can get a working prototype of course.

Also I attached the 3D model I used to get the angles/positioning of water outlets right mostly because it looked cool and I was proud of myself for even getting that generated.

Tstat.png
 

FJBen

SILVER Star
 
 
Joined
Apr 1, 2004
Messages
3,633
Location
West
Interested. Mine is in decent shape minus one of the lower outputs is a bit more crusty than I would like. I think it will be fine, but I like where you are going with this. First and foremost is quality of unit. That said I won't pay $$$$ unless I absolutely have no other choice for it.

I like the billet idea first, but injection could be a good idea as well if it's stout enough.
 
Joined
Aug 9, 2012
Messages
228
Location
Dallas, TX
Yep, I agree. It may be that it's too costly to be a realistic option but I should have a better idea once I can fit the base and then finish the complete model.

Also, I have no idea what billet will run - I'm just assuming it'll be pretty pricey based on what I've seen billet parts advertised for. I'll definitely seek out a quote on that option before making a decision.
 
Joined
Aug 9, 2012
Messages
228
Location
Dallas, TX
Got the rough draft base back. Little bit of overhang and not quite 100% alignment on the bolt holes (it looks more aligned than the picture suggests) but I'm kinda proud it bolts up with no modification as is. I will tweak out the misaligned portions on the next iteration that will be the full piece.

Not bad for a first attempt with a ruler (current version was calibrated with good calipers). This piece is the difficult part, the other sections just have to approximate the same angles. Adding the correct dimensions for the rad hose and holes that will be tapped for hose barbs was easy.



 
Joined
Aug 9, 2012
Messages
228
Location
Dallas, TX
My hope was to find a way to produce them that would be cheap enough that it was reasonable to pick one up for a spare 'cause it sucks when they go.
 

brownbear

Mod in Hibernation
Moderator
 
Joined
Sep 6, 2004
Messages
6,853
Location
North West Ontario
Just some fyi on corroded parts.

In the picture it doesn't look completely un-salvageable. I used to restore aircraft parts to some extent with corrosion damage.

You can remove the brass fittings, media blast using (non silica) glass bead, or plastic bead. To remove all the corrosion, or use an alum prep type chemical, but use caution, as you can erode too much. Then have the part anodized. Install new brass fittings.

some deep pits on sealing surfaces can be filled with devcon putty for aluminum.
 
Joined
Aug 24, 2016
Messages
20
Location
Smithers, BC
My hope was to find a way to produce them that would be cheap enough that it was reasonable to pick one up for a spare 'cause it sucks when they go.
Definitely interested. And I really like the idea of experimenting with 3D. In a few years it should solve a bunch of issues with availability of rare stuff for cruisers.
 
Joined
Nov 4, 2013
Messages
7
Location
Colorado Mountains
We had the problem of the thermostat outlet housing hose barb tubes being severely corroded, but the casting still OK. With slight heating, the hose tubes easily pull out of the housing, thus allowing the housing to be threaded to accept standard brass hose barbs available anywhere. See photo

Repaired Thermostat Housing 13BT.jpeg
 
Joined
Aug 9, 2012
Messages
228
Location
Dallas, TX
I'm still working on this but it got sidelined because of a few big work projects and a minor accident.

I thought about doing the bar replacement originally but unfortunately the large diameter flange and the base have a lot of corrosion on mine. I can get by for now with the unit but it is not going to last for the long haul.
 
Joined
Aug 9, 2012
Messages
228
Location
Dallas, TX
I'll post up here as soon as I do full version demo for fitment. The best way forward is to see how many people will commit to one as most of the consumer level production options give a pretty good volume discount, especially in the jump from 2 or 3 to 15+.

The original is NLA but Dyna's use this: 16333-58080 and you'll need at least one plug for an extra hole: 90341-12006

I can't remember if the newer lower unit requires and o-ring or a paper+rubber rim style gasket....someone else might be able to help. They are both available.
 
Joined
Dec 2, 2015
Messages
326
Location
Northcliffe, Western Australia
For my BJ73 I removed the factory steel barb and tapped it 1/8npt. I had a corroded notch in surface that the radiator cap seals on, I used some steel epoxy to fill it and it's been great for 3 years now. Though not long after that I converted to a HDJ79 radiator and blocked off the radiator overflow pipe on the thermostat housing with a threaded bung. The HDJ radiator has the radiator cap built in so I'm using that overflow to take the load off the repair to the thermostat housing.

Personally, I'd look at getting the corrosion welded up and machined. A cylinder head repair shop will be well equipped and experienced for this sort of job.

If your cooling system is really corroded and junky I'd give a thought to your oil cooler, it's had to suffer through this too.
 

brownbear

Mod in Hibernation
Moderator
 
Joined
Sep 6, 2004
Messages
6,853
Location
North West Ontario
I would not bother welding in my opinion.
But media blasting with a fine glass or plastic bead, (never sand or metal) will remove the corrosion. Then treat it with alum prep and alodine conversion. It turns it kind of golden in colour. But don't leave the alodine on too long, only looking for light gold colour. Too long is not good.
Then you can paint it with epoxy paint on exterior surfaces only. Paint will stick really well.

A dev con aluminum 2 part putty can fill any voids and you can sand it on a flat table with some fine grit paper. To "machine" it flat.
 
Top Bottom