The 24 Hours of Lemons Forums → Lemons Tech → Brake caliper substitutions
What would you guys do in a similar situation?
Call these guys and make sure it's really for a Humber Super Snipe?
http://www.kdparts.com/infovehicle/brem … fault.aspx
-=Tom
All I can say is, WOW, you guys are fantastic! There are so many leads here that it will take me a few days to run them all down. I'm going to hit the U-Pick, three Pick-A-Part, and two Ecology Auto Parts, yards tomorrow. I'll have my cardboard template and all your suggestions in hand to narrow down my search.
The multiple suggestions for TR4 (or upgrades thereof) are appreciated, but I had already determined that they are for 10" rotors and won't fit the Super Snipe. Since the upgrades came from Toyota pickup trucks, I'm going to look at some of their later models.
The KD Parts calipers are simply too good to believe. If they are real, that is a way to just throw money at the problem and get it solved instantly. I'll call them on Monday, but I suspect it may be a case of advertising something for every car ever made, but not actually having it. I hope I'm wrong.
This is truly an embarrassment of riches! Thanks to all of you. I'll let you know how it turns out.
but I suspect it may be a case of advertising something for every car ever made, but not actually having it.
Unfortunately this.
PartStain is one of the worse offenders for this:
http://www.partstrain.com/ShopByDepartm … per/Humber
I started to say last night, before my Laptop locked me out of it, how do you know the TR4, TR6, Girling 16 calipers won't fit the larger discs on the Snipe? If the mount for them moves them closer to the outside edge of the disc it could work. The reason I back peddled on the Wilwood is the measurement on your cardboard template would indicate you need more than 4" between the caliper mounting holes and the outside edge of the caliper. The Wilwoods have less than 3". If you need to build a spacer anyway, you might as well just start with some cheaper junk yard pieces.
I started to say last night, before my Laptop locked me out of it, how do you know the TR4, TR6, Girling 16 calipers won't fit the larger discs on the Snipe? If the mount for them moves them closer to the outside edge of the disc it could work. The reason I back peddled on the Wilwood is the measurement on your cardboard template would indicate you need more than 4" between the caliper mounting holes and the outside edge of the caliper. The Wilwoods have less than 3". If you need to build a spacer anyway, you might as well just start with some cheaper junk yard pieces.
I did not actually check the TR4 calipers against the Super Snipe -- I just assumed that because of the smaller rotor that it wouldn't. My bad.
Also, I screwed up on the dimension labels on the template. Those are diameter measurements, not radius. So, the mounting radius is actually 3.32" and the distance from the mounting holes to the rotor edge is approximately 2.88". The Wilwoods will probably work. But see my next post...
Wow, did I get lucky today!
I started out this morning, determined to find some brake calipers that could be used with the Super Snipe. I had a list of six self-serve wrecking yards (in three counties), my cardboard brake mounting template, and my tool kit.
As I arrived at the first one, in the upper San Fernando valley, I missed the turn for the entrance. While getting turned around, I found myself in front of U-Pull-It, with a sign advertising exclusively foreign car parts. It wasn't on my list, but what the heck, I'll try it first.
Even by wrecking yard standards, this was the low-rent district. Most of the cars had been pretty well picked over, with some now totally unrecognizable by make or model.
Since the disk rotors on the Super Snipe are 1/2", I could easily ignore any cars with the more-modern ventilated rotors. I had been alerted earlier to Toyota pickup trucks as being good candidates, so that's what I looked at first. Unfortunately, after removing calipers from two likely trucks, they simply did not fit my template.
Discouraged, I kept walking up and down the aisles, looking for 1/2" wide, 11" diameter rotors. Suddenly, there it was: just what I was looking for! A few measurements showed that it was a very close match. Because so much of the car had been removed, it took a bit of detective work to determine that it was (or had been) a Mercedes 240D.
Unfortunately, those German assembly line workers had torqued the bolts far beyond what my puny efforts could dislodge. I would have to bring a BIG breaker bar next time. In the meantime, I would keep looking.
A Mercedes 250 in the same row looked like a good possibility, but had the same problem, plus the calipers were fully equipped for an ABS system and much larger.
Then, there it was: a 1972 Mercedes 300 in what appeared to be excellent (for my purposes) condition. Amazingly, I was able to remove the bolts. I couldn't budge the hose fittings, but that's what a utility knife is for. 
With bated breath, I held my template up to the calipers. It was a perfect fit!!!
As I was removing the second caliper, a guy who had seen me working on a Toyota wandered by and asked why I was taking parts off a Mercedes now? I explained the whole Super Snipe problem and showed him the template. He exclaimed, "Oh, you're an engineer!"
The price was exceptional: $13.74 each, plus tax, $2.00 entry fee, and "environmental charge", for a grand total of $32.63. You can't beat that with a stick.
After taking them home and cleaning them off, I took them out to the Super Snipe. I already knew that the caliper mounting holes were 1/2" and the Super Snipe bolt threads were 7/16", but sleeving a hole would be a minor problem.
To my great joy, the calipers were a perfect fit! The top of the brake pads just kissed the outer edge of the rotor. The rotor fit exactly in the middle of the calipers too. The final test was to see if the wheels would clear these fat calipers, and they did -- just barely.
The only remaining task is to make four thin sleeves to reduce the 1/2" holes to 7/16". Simple, when you own a lathe.
On my way home, I stopped at my friend Richard's house to drop off a book. I told him of my success, and he suggested that we check his stock of parts. Sure enough, he had a 4" long piece of steel tubing with an 1/2" OD, and just slightly under 7/16" ID! That, and a 7/16" reamer would solve the problem -- and he loaned me one!
All I will need to buy is some grade 8 bolts and new brake hoses. I'll probably also replace all the steel brake tubing since it has been open to the elements for the last 20 years. Rust city! The master cylinder will also need attention, but that will be an easy job compared to this. Oh, there's still the rear brakes, but that is probably just a slave cylinder rebuild.
I am confident that the front brakes will be sufficient to stop the Super Snipe. It weighs 3500 pounds, and the Mercedes is 4200. Considering German over-engineering, I think they will work well. Oh, and the pads are in almost-new condition!
I have had so much good luck today that I'm afraid of what Mr. Murphy has in store for me now.
Edit: Further research shows that the mounting hole diameter is 12mm, and that the mounting bolts for late-production TR6 calipers are exactly what I need: 12mm shank with 7/16" threads! Now the decision: spend $9.85 each for the bolts, or spend an hour or so making the sleeves?
That is awesome! I love the all foreing yard in Sun Valley. I thought you were going to say you pulle the calipers of one of the 6 old english taxi cabs they have stashed in one corner. That is the yard where I fount the Car & Driver project Mk1 Jetta with the custom Recaro interior. Unfortunately the supercharger was gone when I found it. Just to prove how low rent that area is, I met a guy there who was into Porcsche 924's and was getting some 944 parts to bolt onto his (don't remember what part) only when we walked out to the parking lot, he no longer had a 924! So I had to give him a ride home in the bed of my pick up.
Looks like we'll all be hunting Snipe in the near future.
This is awesome!
There you have it folks. A caliper upgrade for a Super Snipe, ferreted out right here on Lemons.
This thread is how I know I'm in the right place. Few things are more satisfying than finding that random part X from car A fits on car B.
Dang, I almost told you so. I wanted to chime in that the W108 Benz calipers might be something worth looking into... but you arrived there before I could bloviate about it.
Should be a fair choice of pads available, and yes, any 300-class Benz of that era is going to be an order of magnitude heavier than a Snipe, Super or otherwise. A 300SEL is the only '72 model MB beginning with 300- speaking of, it's not a 6.3, is it??
Should be a fair choice of pads available, and yes, any 300-class Benz of that era is going to be an order of magnitude heavier than a Snipe, Super or otherwise. A 300SEL is the only '72 model MB beginning with 300- speaking of, it's not a 6.3, is it??
I don't know shit about Mercedes, so all I can say is that the trunk lid simply said "300". It was a 4-door sedan. The reason I say 1972 is that the data plate had "5/72" on it.
My notes are a bit confused, but I wrote down a VIN: 114 011 12-01 3721. That might be for a 250D I was looking at, however.
just saying ...
also looks a lot like a MB front caliper: http://www.rockauto.com/catalog/moreinfo.php?pk=523109
If you can, go back and take a picture of the motor. If it looks like this, I'll pay you to pull, store and bring the motor to infinion.
did the car look like this?
Edit: Further research shows that the mounting hole diameter is 12mm, and that the mounting bolts for late-production TR6 calipers are exactly what I need: 12mm shank with 7/16" threads! Now the decision: spend $9.85 each for the bolts, or spend an hour or so making the sleeves?
Seriously? A metric shank and SAE threading? I know that British cars of that period are screwy in ways unknowable to mortal man, but that's even outside the realm of WTF.
CowDriver wrote:Edit: Further research shows that the mounting hole diameter is 12mm, and that the mounting bolts for late-production TR6 calipers are exactly what I need: 12mm shank with 7/16" threads! Now the decision: spend $9.85 each for the bolts, or spend an hour or so making the sleeves?
Seriously? A metric shank and SAE threading? I know that British cars of that period are screwy in ways unknowable to mortal man, but that's even outside the realm of WTF.
Don't forget the occasional Whitworth fitting. Late TR6's (and now my Super Snipe) have all three: Inch, Metric, and Whitworth!
Two of the Super Snipe carburetor (Zenith W42) parts require a Whitworth nut driver (or thin-wall, deep socket), which seem to be unobtanium. My choice seems to be to hire an EDM shop to make one for me.
Take deep socket, turn down on lathe?
Take deep socket, turn down on lathe?
The trick is finding a deep Whitworth socket to begin with, at least for less than a down payment on the British national debt.
Is drill out and re-tap with normal threads an option? You could use socket head cap screws if the head diameter is a concern.
~sam
Is drill out and re-tap with normal threads an option? You could use socket head cap screws if the head diameter is a concern.
~sam
You could go the other way as well (i.e. turn down the metric bolt a little and rethread it to 7/16). I've resurrected several long dead Triumphs and usually put the Toyota brakes on the front and it always chaps me a little bit to spend 40 bucks on 4 bolts. Even so, it's about a break even deal to buy loaded Toyo calipers and bolts than rebuild the stock TR calipers. Plus the braking feel is much better. I can't think of anywhere they still used Whitworth on the TR6 but the TR4 still had it. This weird metric/inch bolt thing came about because Girling switched the part to metric and I guess Brit Leyland decided it would be easier to make a weird bolt and brake lines than switching the rest of the car to metric.
neophile_17 wrote:Is drill out and re-tap with normal threads an option? You could use socket head cap screws if the head diameter is a concern.
~sam
You could go the other way as well (i.e. turn down the metric bolt a little and rethread it to 7/16). I've resurrected several long dead Triumphs and usually put the Toyota brakes on the front and it always chaps me a little bit to spend 40 bucks on 4 bolts. Even so, it's about a break even deal to buy loaded Toyo calipers and bolts than rebuild the stock TR calipers. Plus the braking feel is much better. I can't think of anywhere they still used Whitworth on the TR6 but the TR4 still had it. This weird metric/inch bolt thing came about because Girling switched the part to metric and I guess Brit Leyland decided it would be easier to make a weird bolt and brake lines than switching the rest of the car to metric.
Cutting new 7/16 threads on four metric Grade 10.9 bolts that my life depends on? I don't think so. The time and effort to make the sleeves is far less.
You may be right about no Whitworth on the TR6, but check the nuts for the big electrical connections on the starter and generator. Lucas may have changed to inch by the 1970s, but they stayed Whitworth for many years.
To be clear I was referring to the carb bolts which aren't as highly stressed. Granted I haven't seen the setup but I'd guess you could cut the heads off, extract the bolts and then helicoil or move to the next standard size to avoid an expensive special tool purchase.
~sam
It's pretty easy to just grind down the flats on the hex head to the next smaller metric or SAE wrench size and not muck with the threads at all. I did that with a few PITA bolt on an old Jaguar. As an added bonus you won't need as thin a wall on your sockets since the size will be smaller. But you have to get the bolt out of the hole first.
It's pretty easy to just grind down the flats on the hex head to the next smaller metric or SAE wrench size and not muck with the threads at all. I did that with a few PITA bolt on an old Jaguar. As an added bonus you won't need as thin a wall on your sockets since the size will be smaller. But you have to get the bolt out of the hole first.
Excellent idea, and I'll do just that if I ever get them out. They are not bolts, however, but a couple of those mysterious brass internal parts of the carburetor. At the moment the carb seems to work so I guess I got away by using lots of nasty solvents, an ultrasonic cleaner, and compressed air.
just saying ...
Jackasic wrote:also looks a lot like a MB front caliper: http://www.rockauto.com/catalog/moreinfo.php?pk=523109
If you can, go back and take a picture of the motor. If it looks like this, I'll pay you to pull, store and bring the motor to infinion.
http://bringatrailer.com/wp-content/upl … otor_1.jpg
did the car look like this?
I went back this morning and took a good look. Apparently my note-taking needs lots of improvement. The car in question was a 250, not a 300 of any kind. The engine did not look at all like your photo. There were a couple of Mercedes with engines that looked similar to your photo, but none of them had that Y-shaped manifold with long tubes the length of the engine. Most of them also appeared to be missing some parts. Sorry for the false alarm.
ah sucko, thanks for looking though. That motor only came in 300's, so it helps to narrow the search. Easiest way to tell is the intake manifold. Let me know if you run across one.
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