Hello all, I hope someone can help with the following...

The water pump drive on this car is missing and has been since my friend bought the car a few years ago. He has not driven it much, but says it has never overheated. The water pump itself is seized up solid, and, indeed, my short test drives have not caused any overheating. Nonetheless, this needs to be addressed.

What does the drive look like? Can someone please post a photo and/or description? I gather this drive must be unusually flexible, as it needs to allow for considerable mis-alignment of the two shafts, given that the driving shaft position varies as the timing chain tension is adjusted. Does anyone here have a spare drive assembly they would be willing to part with for our project?



The other problem we have identified is the rear axle drive pinion, and, to a lesser extent, the ring gear. Here are a couple photographs of the pinion gear which is in truly frightful condition. Clearly we need a replacement — this one may do for putzing around town but I would not trust it for an extended road trip.





Our Sept/23 Parts Book shows this as Part # #21156 (for split axle housing)



Would someone hear have a usable matching ring and pinion that we could acquire for this project? Or, can someone advise what other models of Star/Durant family might have used this same part #? And failing that, is there some other solution that Star mechanicians have used to overcome this problem?

Many thanks, looking forward to checking the forum tomorrow AM!

Where Are You From? Edmonton, Canada

Do You own a car built by Durant? No, but helping with one...

There is a good picture and a water pump rebuild article in the tech page under maintenance items.
I varied the gasket thickness behind the water pump mount to closer align the shafts

Where Are You From? cerritos ca

Do You own a car built by Durant? yes

Thanks for your note, Dave. There is one small photo at that link showing a water pump with the drive connection in place. Our Parts Book lists the coupling and clamp/bolts but does not illustrate them.

As near as I can tell, it looks like a heavy red rubber hose, clamped on each end to the pump and drive shafts. Each clamp appears to consist of a pair of half-circles with a through bolt (offset 90° from the other clamp) that passes through a hole in the shaft.

Can anyone here confirm we are on the right track with this description? If so, we can make the necessary hardware from scratch, although it would be nice to purchase two original clamps if there are some available...
_ _ _ _ _ _

And we're still really hoping to hear from someone about replacement ring and pinion gears!

Thank you.

Where Are You From? Edmonton, Canada

Do You own a car built by Durant? No, but helping with one...

Hi Chris.....

Here is what a new old stock water pump coupling looks like. These are genuine Durant parts with the part number stenciled on them. Cost is $15 each or 2 for $27.

Finding a good set of used gears can be difficult. Most are in worse shape than yours. I have some new old stock gears also. Count the teeth on your ring and pinion and I will check my stock.

Hope this helps.....

Frank

Where Are You From? Hookstown, Pennsylvania

Do You own a car built by Durant? 17 Durant & Star cars & a Durant Dort buggy (one horse power)

Hello Frank, so nice to see your message tonight.

It looks like that coupling will do fine, although we will have to relocate one of the bolt holes — our holes are 2-5/8" centre-to-centre, and from your photo the NOS holes are about an inch further apart.

You've got me all excited about the possibility of a NOS ring & pinion! Our pinion is an 8 tooth, the ring gear 39. Our pinion gear is marked on the end "B 41023 2-7 8-39".

I need to correct some information in my original post: I stated our pinion gear and shaft was part #21156, assuming we had the stock pinion for a split differential housing (which our housing is). However, and this is obvious in my photo, our pinion shaft is actually of the tapered end style as used with a solid differential housing. Anyway, we need the tapered end style part #20636, or, failing that, possibly a straight/splined end shaft #21156 with whatever else is needed to mate with our differential housing and driveshaft.

Looking forward to hearing back from you soon!

Where Are You From? Edmonton, Canada

Do You own a car built by Durant? No, but helping with one...

I might have some of the clamps but I'm out of the country now. I'll be back in April and will check then.

Your pump looks to be considerably mis-aligned. I'd try to improve that before connecting it up.

Frantz Fraitzl rebuilds these. See links page for Vancouver Durant Parts.

Where Are You From? Just North of San Francisco

Do You own a car built by Durant? 1925 Star

Thanks for your suggestion, VInce, and the offer to check for clamps next month. We are getting a drive coupling from Frank but will not have to install it for a while.

The shafts are 'way out of line. There is no slack in the timing chain that would allow us to pivot the generator further out from the block. I'm considering a wedge-shaped thick gasket/spacer between the water pump and block — thick end up — to pivot the pump itself into closer alignment with the drive shaft. Comments?

Where Are You From? Edmonton, Canada

Do You own a car built by Durant? No, but helping with one...

Originally, metal shim packs were used to shift the pump out to align the shafts. The layers would be sealed with shellac.

Whenever the timing chain is tightened, it moves the generator further out, and the pump has to go with it or the side loads harm the bushings, not to mention, strain the connector.

I made a connector from high temperature silicone rubber hose that I got from a mechanic who used it to connect air-pump pipe to an exhaust system. It's strong and heat resistant. The clamps can be fashioned from pieces of conduit clamps with holes drilled for the fastener. I think some modern thread locker would suffice to keep the little stovebolts from loosening up. Probably peened them over in the old days.

I was thinking about making up some shim packs for sale, but don't know if it's worth bothering. With computer-controlled laser cutters it would be easy. The programming would cost the most.

By the way, the pump from a 75 engine is a superior design and I think it is interchangeable.

Do You own a car built by Durant? yes

The fact your engine didn't overheat is due to the thermosyphon cooling effect made famous by Henry Ford and used in tractor engines as well. It isn't the best system, for sure, so you'd better not do it for long, heavy loads. Fords were famous for boiling over.

Avoiding the problem of leaking pump seals was the big advantage. Eventually some clever seals replaced the plumber's packing that sort of worked. Whoever invented them must have lived happily afterward on his royalties.

In the days of yore, whenever you stopped to fill gas, you had to check your water level, your oil level, your battery level, and your tire pressure. Everything leaked. So did hydraulic brakes with some frequency. Some preferred the security of steel from heel to wheel.

Today we are spoiled by the no-maintenance ethic. If it doesn't work, it can't be fixed.

Do You own a car built by Durant? yes

In my former life, I was a power transmission designer. This is known as a spiral bevel gear. It looks pretty conventional; it would be no challenge at all to make new ones, but..., but..., they would really cost, really cost. You would be in the realm of the proverbial space shuttle toilet seats, etc.

Only a few companies in the US have invested the money in tooling to make precision gears. It's a risky business. They tend to cater to premium-priced custom products. Big profits on some jobs offset big losses on others. There are several in Minnesota and in other major cities. The mass market uses in-house shops or else imports them.

You leave yourself vulnerable to quality problems unless you can control every step of the process in your own shop. This has been changing. For the past 20 years big efforts have been made to make manufacturing technology transferrable for the world market. Supposedly any shop in the world would produce the same part if you sent along the piece description in enough detail.

I could give you a lecture on gear design and production, but I'll spare you the most of it. Just to summarize, you need to buy the correct alloy steel, prepare the metal, by drop-forging, for example; turn the blank on a lathe, cut the teeth,(almost certainly these were cut on Gleason machines) heat treat them, then grind them. You will need a thread mill to cut the screw threads, and either a keyway cutter or a spline cutter.

The gear machinists occupy the highest rung of machine shop practice and are paid accordingly. Setting up the old Gleason machines was far from a trivial task. And it had to be redone for every different part number.

A big name axle supplier would produce hundreds of thousands of parts with one set up, over dozens and dozens of identical machine tools. Skill level would mostly involve chucking in the blank and removing the finished piece. You can get cheap parts that way.

By the way, this pinion looks pretty bad. How bad is the gear it runs against? Were the bearings worn out? You need to maintain precise alignment. Lubrication could have been a factor.

In general, the pinion has to be mated with the driven gear and each be marked with the setting dimensions. Once assembled and run together, they shouldn't be seperated.

For our old stuff, compromises must be made. There may be ways this gear could be salvaged, but I don't know who would want to do it. Like friction-welding or laser-welding a new gear to the stub shaft. It's not as though they are helicopter gears.

Maybe you could modify some other set of gears? Hypoid gears didn't entirely replace spiral gears until mid 50's.

The Gleason Company probably knows exactly who makes, or made, these or similar gears, but they aren't going to tell us.

Do You own a car built by Durant? yes

Thank you Cdmn for your thoughtful and informative posts. Much appreciated.

We have sourced NOS replacement ring & pinion gears from Frank Witkowski. The new set has the added benefit of improving the final drive ratio slightly from 4.875:1 to 4.44:1 for a 9% reduction in engine speed.

Our water pump alignment issue will not be as bad as it first looked — the pump shaft was seized, off-centre, in the worn bushing, and the resulting offset put the two shafts badly out of line. We are re-bushing the pump now and making a new packing nut. This should bring the two shafts into much better initial alignment and we can shim from there.

I am impressed by the thermo-syphon cooling we observed while running with a seized pump. I know Model Ts were all thermo-syphon after the first 2,500 production, but they also maximized the efficiency with short, large-diameter, direct coolant piping between the engine and radiator.

Where Are You From? Edmonton, Canada

Do You own a car built by Durant? No, but helping with one...

Chris, I found the waterpump drive clamps I said I had but they are not for a 24 or 25 Star. They have a larger diameter to accomodate a larger hose.

Does anyone know what they might be for? A six cylinder?

Where Are You From? Just North of San Francisco

Do You own a car built by Durant? 1925 Star

I believe they would fit the big Flint six engine. I'm sorting parts now for an E55 and have a large pair set aside for it.

Where Are You From? Big Ditch, MO