This wheel brake cylinder drives me nuts. (37 Roadmaster)

[chstickl]

Hi there, I need some help to find out what I can do.

I am a proud owner of a 37 McLaughlin Roadmaster C. As you can see on the photo, the thread of the left front wheel cylinder is broken and I am trying to find a replacement. Living in Germany - a heaven for all metric parts and hell for inch parts - I have great difficulty finding a replacement cylinder.

The old cylinder carries a number C 9346 and "made in the USA" - does anybody know what this is and where to get an exact copy?

Strage are also the measures: Bore between 1" 9/32 and 1" 5/8 (measured with a metric gauge 32.8mm, though). Literature tells me it should be a 1" 1/4, Bobs only has 1" 1/8.

So if I don´t find an exact replacement, I have to replace both sides and risk a weaker brake efficiency.

There may be compatible aftermarket brake cylinders which I can´t find from here. Does anybody have a good advice or know what I should do?

Thanks so much for your help,

Chris

[Mark Shaw]

I suggest you call Dave Tacheny 763-427-3460 (He does not do email...).

[trp3141592]

Hi,

32.8 mm is nowhere near the inch-measures that you listed. Do you have a typo error in your thread?

32.8 mm = 1.2913

1-9/16" = 1.5625

1-5/8" = 1.625

The largest Buick cylinder I could find on line was 1-1/4" = 1.250.

Wish I could be of more help.

--Tom

Edited August 15, 2013 by trp3141592 (see edit history)

[chstickl]

Tom,

thanks for your reply. Yes I am now looking for 1.25" cylinders and will replace both sides. God knows what has been built in there by someone. Would you have a source that you can share with me?

Chris

[1939_Buick]

As you car is Candian built 37 McLaughlin Roadmaster it may be different to USA production. My understanding is for some years Candian Buick's used Chev truck brakes. Have seen this on '38 & '39 McLaughlins. Does you car have 5 or 6 wheel studs ? [6 studs = Chev] Try https://www.chevsofthe40s.com/index.lasso

Edit: https://www.chevsofthe40s.com/dept/Car/cat/180C/Brake_Parts.html

Edited August 16, 2013 by 1939_buick (see edit history)

[trp3141592]

Hi,

Oldbuickparts shows the Buick front wheel cylinders as available. I looked at other sources as well, but they all required a usable core, and your core is not usable since the casting is broken. The ones I found are at:

Old Buick Parts - CARS. Inc.

I have never bought from these folks, so I have no recommendation, good or bad.

--Tom

[chstickl]

Tom, thanks for the advice. Unfortunately these are the smaller cylinders like used in Series 40 and 60. Series 80 and 90 have bigger 1-1/4" cylinders and they seem to be harder to find.

Chris

[bobj49f2]

The attached page was in the May-June 2001 issue of the Torque Tube. It lists brake parts from newer or more common vehicles that will fit our old Buicks. I recently checked, NAPA has all of the parts. With a little cross referencing you can also find them at Rock Auto on line.

This is the NAPA part#7536, about $25 in my area.

new_brake_parts.pdf

Edited August 17, 2013 by bobj49f2 (see edit history)

[Leif Holmberg]

Why don`t you ask some mecanic to take the broken threads out if you can`t do it by yourself,it can`t be a big problem.

Leif in Sweden

[jenz38]

Leif,

The pic looks like that the thread for the hose is broken completly off,there isnt material left for repair..

Christian,i think too,the best is to make both front cyl. similar new. Hope you have then no Problem with the thread sizes for the hose at the new cyl.

[Leif Holmberg]

To me it looks like the top of the "nut"is gone(broken),can`t belive that should be a big problem to fix,but of course you need some tools to do it.Can`t be a big problem for a skill mecanic.

Leif in Sweden.

[bobj49f2]

The only two ways I can think of to remove a broken bolt in a threaded hole is to either drill it out and retap the hole, which you can't do because this is not a through hole. Second is to use an easy-out, which I hate using because there's a good chance of breaking the easy-out in the bolt, causing another, bigger problem because easy-outs are hardened steel. But with this thread there isn't enough material for an easy-out to even grasp. If you have a small enough chisel you might be able to break the fitting out but that's a lot of work without any assurance of having a good outcome. I think getting a new part is the only way to go. I don't like screwing around with brake parts. If you can get the old threads out you might end up with a leaky fitting. Can you get the old Chevy truck parts easier in your country?

[stealthbob]

I recently checked, NAPA has all of the parts.

I was shocked one day when I went to NAPA looking for bleed screws with the nipple on them...out walks the guy with a brand new cylinder for my Buick just to have a reference to find the right screw. He had all 4 correct cylinders in stock all for $70 with the wanted bleed screws, I bought them all and ran home. Since then I go there first for everything...then start elsewhere. They guy just loves hunting for these parts for me, I have him building a front end complete rebuild kit for me.

This may not be as easy for you pre-war guys and won't help the non NA guys but certainly is an easy first check option..

[trp3141592]

Hi,

Hagens Highway Auto Parts shows the following interchages for the 1937 Buick Roadmaster front wheel cylinders. In all cases, Hagen requires a usable core casting as a core. Perhaps other venders may be able to supply this cylinder with a cash core rather than a casting.

[h=1]03384[/h][h=3]Brake Wheel Cyl. Assy.[/h]1-1/4 Bore

[TABLE=class: twidth]

<TBODY>[TR=class: row1]

[TD=class: col1]BUICK[/TD]

[TD=class: col2]CADILLAC[/TD]

[/TR]

</TBODY>[/TABLE]

[h=1]BUICK[/h]

1936 - 60 Century 320.2-8cyl 122wb

1936 - 80 Roadmaster 320.2-8cyl 131wb

1936 - 90 Limited 320.2-8cyl 138wb

1937 - 80 Roadmaster 320.2-8cyl 133wb

1937 - 90 Limited 320.2-8cyl 138wb

1938 - 80 Roadmaster 320.2-8cyl 133wb

1938 - 90 Limited 320.2-8cyl 140wb

1939 - 80 Roadmaster 320.2-8cyl 133wb

1939 - 90 Limited 320.2-8cyl 140wb

1940 - 80 Limited 320.2-8cyl 133wb

1940 - 90 Limited 320.2-8cyl 140wb

[h=1]CADILLAC[/h]

1936 - 70 131wb; 75 138wb, 156wb 346-V8

1936 - 80, 85 368-V12 131wb, 138wb, 156wb

1937 - 75 346-V8 138wb, 156wb

1937 - 85 368-V12 138wb

1939 - 90 431-V16 141wb

Hagens also shows 1-1/4" bore wheel cylinders for Chevy Trucks, with a cash core charge, but the inlet is at 90-degrees, not at an angle. I don't know how much room is avaialable behind your brake plate. Perhaps an angle fitting could be used. Note: the illustration is labelled, "typical," meaning that the actual part may look different in some manner. You can call or email Hagens and ask for measurements. Hagen's Hiway Auto Parts, Inc.

Account <FORM method=get action=/><INPUT style="WIDTH: 230px; BACKGROUND: #eef" id=search-all class=ui-autocomplete-input type=text name=search autocomplete="off" jQuery19109397032064837836="43"> <INPUT style="PADDING-BOTTOM: 2px; PADDING-LEFT: 2px; PADDING-RIGHT: 2px; PADDING-TOP: 2px" class="btn3d purple small" value=Search type=submit>

</FORM>

• 
  

$ 65.00

1350-18010

[h=1]18010[/h][h=3]Brake Wheel Cyl. Assy.[/h]

[TABLE=class: twidth]

<TBODY>[TR=class: row1]

[TD=class: col1]CHEVROLET - Truck[/TD]

[TD=class: col2]GMC - Truck[/TD]

[/TR]

</TBODY>[/TABLE]

[h=1]CHEVROLET - Truck[/h]

1-1/4 Bore 1953 - 3100-H 1/2ton 116wb, 3600-J 3/4ton 125.25wb, 3800-K 1ton 137wb

1-1/4 Bore 1953 - 3700-K 3/4ton 125.25wb, 3900-M Forward Control 1ton 137wb

1-1/4 Bore, w/ 14in Brake 1953 - 3700-K 3/4ton 125.25wb, 3900-M Forward Control 1ton 137wb

1-1/4 Bore 1954 - 3100-H 1/2ton 116wb, 3600-J 3/4ton 125.25wb, 3800-K 1ton 137wb

1-1/4 Bore 1954 - 3700-K 3/4ton 125.25wb, 3900-M Forward Control 1ton 137wb

1-1/4 Bore, w/ 14in Brake 1954 - 3700-K 3/4ton 125.25wb, 3900-M Forward Control 1ton 137wb

1-1/4 Bore 1955 - 3100-H 1/2ton 116wb, 3600-J 3/4ton 125.25wb, 3800-K 1ton 137wb

1-1/4 Bore 1955 - 3100-H 1/2ton 116wb, 3600-J 3/4ton 125.25wb, 3800-K 1ton 137wb

1-1/4 Bore 1955 - 3700-K 3/4ton 125.25wb, 3900-M Forward Control 1ton 137wb

1-1/4 Bore, w/ 14in Brake 1955 - 3700-K 3/4ton 125.25wb, 3900-M Forward Control 1ton 137wb

1-1/4 Bore, w/ 14in Brake 1955 - 3700-K 3/4ton 125.25wb, 3900-M Forward Control 1ton 137wb

1-1/4 Bore 1956 - 3100-H 1/2ton 116wb, 3600-J 3/4ton 125.25wb, 3800-K 1ton 137wb

1-1/4 Bore, w/ 14in Brake 1956 - 3700-K 3/4ton 125.25wb, 3900-M Forward Control 1ton 137wb

1-1/4 Bore, w/ 14in Brake 1957 - 3400 3/4ton 104wb; 3500 125wb; 3700 137wb Step-Van, Forward Control

1-1/4 Bore 1957 - 3800 1ton 135wb

1-1/4 Bore 1957 - 3800 1ton 135wb

1-1/4 Bore, w/ 14in Brake 1958 - 3400 3/4ton 104wb; 3500 125wb; 3700 137wb Step-Van, Forward Control

1-1/4 Bore 1958 - 3800 1ton 135wb

1-1/4 Bore 1958 - 3800 1ton 135wb

1-1/4 Bore, w/ 14in Brake 1959 - 3400 3/4ton 104wb; 3500 125wb; 3700 137wb Step-Van, Forward Control

1-1/4 Bore 1959 - 3800 1ton 135wb

1-1/4 Bore 1959 - 3800 1ton 135wb

1-1/4 Bore, w/ 14in Brake 1960 - P20 3/4ton Dubl-Duti; P23 104wb, P25 125wb; P26 137wb

[h=1]GMC - Truck[/h]

1-1/4 Bore 1953 - 250 1ton 228-6cyl

1-1/4 Bore 1954 - 250 1ton 248.5-6cyl 125.25wb, 137wb

1-1/4 Bore 1955 - 1st Series 152-PM 3/4ton Package Delivery Van 248.5-6cyl 125.25wb

1-1/4 Bore 1955 - 1st Series 250 1ton 248.5-6cyl 125.25, 137wb

1-1/4 Bore 1955 - 2nd Series 150-PM 3/4ton Forward Control 248-6cyl, 287.2-V8 104wb, 123wb

1-1/4 Bore 1955 - 2nd Series 153-PM 1ton Forward Control 248-6cyl 137wb

1-1/4 Bore 1955 - 2nd Series 250 1ton 248-6cyl, 287.2-V8 114wb, 123.25wb, 135wb

1-1/4 Bore 1955 - 2nd Series 251-PM 1ton Forward Control 248-6cyl 114wb, 123.25wb, 135wb

1-1/4 Bore 1956 - 150-PM 3/4ton Forward Control 270-6cyl 316.6-V8 104wb, 125wb, 137wb

1-1/4 Bore 1956 - 250 1ton 270-6cyl, 316.6-V8 114wb, 123.25wb, 135wb

1-1/4 Bore 1956 - 250-PM 1ton Forward Control 270-6cyl 316.6-V8 104wb, 125wb, 137wb

1-1/4 Bore 1957 - 150-PM 3/4ton Forward Control 270-6cyl, 347-V8 104wb, 125wb, 137wb

1-1/4 Bore 1957 - 250 1ton 270-6cyl, 347-V8 114wb, 123.23wb, 135wb

1-1/4 Bore 1957 - 250-PM 1ton Forward Control 270-6cyl, 347-V8 104wb, 125wb, 137wb

1-1/4 Bore 1958 - 250 1ton 270-6cyl, 336.1-V8 114wb, 123.25wb, 135wb

1-1/4 Bore 1958 - 250 1ton 270-6cyl, 336.1-V8 114wb, 123.25wb, 135wb

1-1/4 Bore 1958 - 250-PM 1ton Forward Control 270-6cyl, 336.1-V8 104wb, 125wb, 137wb

1-1/4 Bore 1959 - 250 1ton 270-6cyl, 336.1-V8 114wb, 123.25wb, 135wb

1-1/4 Bore 1959 - 250 1ton 270-6cyl, 336.1-V8 114wb, 123.25wb, 135wb

1-1/4 Bore 1959 - 250-PM 1ton Forward Control 270-6cyl, 336.1-V8 104wb, 125wb, 137wb

1-1/4 Bore, Rear Axle w/ Pow-R-Flo 1967 - P2500 3/4ton Package Delivery Van

1-1/4 Bore, Rear Axle w/ Pow-R-Flo 1968 - P2500 3/4ton Package Delivery Van

1-1/4 Bore, Rear Axle w/ Pow-R-Flo 1969 - P2500 3/4ton Package Delivery Van

1-1/4 Bore, Rear Axle w/ Pow-R-Flo 1970 - P2500 3/4ton Package Delivery Van

Printed: Sat, 17 Aug 2013 00:39:12 -0700 Copyright © 2013 Hagen's Hiway Auto Parts, Inc.

If in fact the only problem with your cylinder is that the hose fitting broke off in the casting (It's really hard to tell from the photo), removal is actually pretty easy if you get a set of left-hand drill bits. (Amazon has them, and any machinery supply place.) Soak the threads with Kroil or other good penetrating oil.

A drill press will be helpful doing this. Carefully start drilling out the broken fitting in a left-handed (unscrewing) direction with a small bit. Then increase the bit size and continue. In most cases the broken fitting will catch on the drill and unscrew with the drill bit. At worst, you can drill it out to where the broken fitting is very thin and use an EZ-Out or a narrow cold chisel to finish the job.

I hope this has helped.

--Tom

[chstickl]

Hi guys,

thanks for all the great tips. I learned a lot from it. Fact is that the iron cast core fitting for the thread broke off completely. So the core is not anymore usable. I´ve seen a lot of offerings to rework old cores etc., but no cores for sale. The cross reference table in torque tube also only references for the Series 40 and 60 models. 80s and 90s have lager wheel cylinders.

1-1/4 bore and 7/16-24 hose fitting. Chevy trucks seem to have very similar brake cylinders, but with a 7/16-20 thread.

In some of the McLaughlin Buicks, Chevy parts have been used. You can recognize this if the wheels have 6 bolts instead of 5 like in my case, so it seems to be an original Buick brake assembly.

There must be after market wheel cylinders that fit. It would be great if through this forum we find that information. I am sure that there are more 80 or 90 series Buick owners out there who will find this useful.

Regards,

Chris

[Bob Engle]

I think you can salvage your casting. I would put the cylinder in a vertical mill and drill the hole out to take a 1/4 x18 TPI NPT pipe thread. Purchase a fitting with 1/4 NPT male threads on one end and your hose fitting threads on the other. If you have a problem finding this fitting, you may consider getting a hose made with a modern standard fitting on the end. If you goggle brake hoses, you will find several American companies that custom make brake hoses to your specs. If you are concerned about sealing the fitting, you could get it silver soldered into your casting. This fitting would add about 1/2 " to the cylinder, but you should have enough clearance for the added length.

Bob

[bobj49f2]

Another article by Dave Lewis in the January 1985 issue of the Torque tube lists the brake hoses for the 80&90 series as NAPA #4497. When you go to the NAPA web site it says the #4497 has Male - 7/16"-20 & Female - 7/16"-24 threads. Maybe Dave got the numbers wrong but it seems like he has done a lot of research. Maybe all you have to do is change the cylinders and the hoses.

[chstickl]

Hi!

I finally found someone who has these parts. After calling at least 15 part suppliers in the US, of which most were not capable of looking up their parts list catalog, I came across Arletta Truck Parts Inc. Geoff was a great help and today the package arrived with exactly the brake cylinders that fit in there, incl. proper brake hoses. I am glad that there are still guys out there who go the extra mile and don´t just look up their database. Definitely worth the money, imagining what options I really had (1 cylinder for 52.10 US$).

In the meantime I also found some reference part numbers that may make it easier to source these parts in the US:

F3384, F9344 (Wagner) sometimes also shown as WC9344

33073 Bendix

172-338 AC Delco

By the way, the thread on the brake hoses are 7/16-24 on both, the male and the female end.

I hope this helps future desperate searchers who are stranded by the usual suppliers like Bobs and Kanter.

2530-00-799-1696, M22976, MC22976, B9D2140A, CITZ2140D, E22976, F22976 Cylinder Assembly,Hydraulic Brake,Master

More Information for WAGNER WC9344