VCCA Home Forums TECHNICAL - GENERAL Mechanical - Engine, Trans, etc 1939 Master Deluxe Steering box

The steering on my 1939 Master Deluxe is rather sloppy. You can turn the steering wheel about 30 degrees before a change is seen. I've checked the rods etal and found that the majority of the slop is in the steering box. I see that Lares offers a rebuild, but that only includes bearings and clean up for almost $700. They do not include the worm gear or sector shaft. I see that I can get a sector shaft and all the bearings, but not a worm gear.
I have tried to adjust the sloop out of the box, but when the steering is OK at center, it binds at the ends of the turn. I'm betting that the worm gear is worn at the center. I have a couple of shafts with worm gears on them, but do not know how I can check them to find the best one, short of installing each and trying them. Any thoughts on how to check these worm gears, Thanks, Mike

When not under load there is really no way to tell. Best to disassemble the gear and inspect.
It is best to inspect all the moving parts by taking the gear apart one time and know what is going on.

If the rubber bushings in the pitman are are a little loose it it multiply to a lot of lost movement.

From what I have read Lares is bad news.

I have heard the same about Lares and most likely will not purchase from them. The pitman arm bushings are tight. I believe that the worm gear is worn at the center. I've been thinking that maybe I can make a pin cradle of some kind in an effort to compare the worm gears I have. I see that the Filling Station has a new sector shaft and I think I may have one buried somewhere in my parts. I do have a complete spare steering box and maybe I can use it to compare worm gears without taking the one in the car out right away. I'm not that good at evaluating these spiral worm gears and sectors. I may see if I can get a machinist to look at them or help me out with picking the best of what I have. Is there any factory drawings of this stuff some where? Thanks, Mike

It is easy to evaluwate the weAR ON THE WORLS SCRES.tHE FRITION SURFAE WILL BE ROUGH AND PITTED. iN THE DAY ABOUT ONE INTEN STEERING GEARS NEED A WORM SHAFT. OTHER THAN THAT THEY ALL NEEDED THE SECTOR SHAT AND BUSHINGS.
wHEN THE WEIGHT IN ON THE WHEELS AND YOU TURN THE STEERING WHEEL AND IT FEELS LUMPY AND CATCHES THE WORM IS BAD.

I wish you could have driven my '39 before I sold it.

Interesting, the worm gear on my bench doesn't seem to be rough or pited. AND my steering is not at all lumpy or does it bind or catch. Maybe I'll proceed by just trying a new sector shaft and bearings and just see how they work. I have at least three worm gears. I still would like to attempt to compare them. THanks for the help. Mike

It would have been nice to see how a good steering system worked.

Well.... I started to look at my 1939 Master Deluxe steering box. I have the open knee action suspension. I think that the sector shaft gear is worn. I can not move the shaft close enough to the worm to eliminate all the lash at the center point of the wheel travel. That kinds indicates to me that the sector gear and/or worm are worn. I started to look for a replacement sector shaft but seems there are two types one for knee action and one for straight axle. Looking at the pictures of the sector shafts, It appears that I have one for the straight axle. My sector shaft has the number 264430 on the top, which doesn;t match any I have seen on the parts books. It there a way to post a picture on this forum? Thanks, Mike
PS the number on the steering box is 264810

Figured out the pictures ---

The two steering gears are very different. Th 1939 Master Deluxe is the same as 1940 (with kneeaction and AAL 1941 thru 1948 models.
The wear you discovered is very common and a correct sector shaft KIT shound be easy to find.

After some looking I found that the 1939 JA steering box is indeed 264810, as I have. The sector shaft number I found in the book is 609941, which matches what I find shown in the Filling Station catalog. Yet the other number they show is 264432 instead of 264430. Maybe a misprint? Anyway I suspose I'll get a new sector shaft and bushings. I figure that maybe the worm rooler bearings/races should be changed also. I'm wondering how those roller bearing races come out? Mike

A few years ago I purchased a steering sector shaft as a NOS item. The box said 1939 1948 Chevrolet excluding JB KB. It tooke me awhile to find it in my parts pile. BUT.... turns out what was in the box is not 1939. I think it is a GM part and has a GM casting number 5662683. The piece is definately never used. I looked the Chevy Master parts book, but could not find this number in the 6.850 section. So maybe it's another GM car, Pontiac, Buick etal? Looking on ebay for some pictures it appears to be 1949 or 1950? I can't use it and would to sell it to someone that does. Thanks, Mike

Well...... after a BUNCH of searching I found a NOS 39-48 steering sector shaft. I have the steering box on the bench so that I can play with the adjustments. This shaft is much better than the old one. The best I could get with the old shaft was about 50 degrees of free play, measured at the steering wheel. This new shaft is less. I can adjust the free play to a minimum at center steering. The wheel will turn lock to lock, but the wheel seems tight. How tight should this be? Maybe I should back off a little on the adjustment? Thanks, Mike

You need to adjust the steering box in the sequence according to the shop manual. End play, side play, then gear clearance.

I made a 300 ounce inch torque wrench to set steering gear boxes. Each adjustment increases the preload/drag.

Note that the shaft should be tight in the bushigs. Most shafts came as a kit and included the bushings - the ushgs are reamed for exact fit.
IF the steering shaft is connected to the box look on the top end of the shaft for the deadcenter mark.

Well...... I have the new bushing in and reamed to fit. The shaft is snug not really tight. The first thing I did was adjust the worm lash. The worm gear nut was tightened so there is about 1 foot pound of pre load on it. The worm gear rolls nicely. Next I set the up/down lash on the sector shaft to about zero. Here I had a little trouble. The sector would not smoothly turn lock to lock. Apparently something is not exactly flat. The sector will turn smoothly through most of the turn, but there is one spot that tends to bind. I inspected the castings and shaft for burrs, but did not see any problems (old eyes don't see very well anymore). I want to chuck the shaft up in a lathe to check how flat the bottom flange and the top of the shaft are. Maybe there is a hump or something on it. Lastly, the gear adjustment was moved in until the gears bound and then moved out until there was no noticeable lash and the gears turned well. This was not as easy as it would seem. I found that if only a very small adjustment was needed, I tightened the casing pivot bolt, one one opposite the adjustment bolt, with the other loose. Then tapped the upper csing with a brass hammer. The adjustment was checked after all the bolts were tight and had to be twicked a little.
I'll will have to take the steering box down to the machine shop and maybe slightly face the shaft surfaces and check the opposite faces in the box. I think this will be a good improvement once it is in the car.
You mentioned a 300 inoz tool for measuring lash, but didn't mention any values as each step was done. Do you have a few approx values? Thanks, Mike

I assume that you have a 1939 shop manual. I only have access to a ‘37 and ‘38. The steering gears are similar but there might be a slight difference.

I also assume that you have a good NGLI 00 grease in the steering gear. Adjusting the box with it dry will give false high preload readings.

One technique I always use when adjusting a steering gear is to back all 3 adjustments off far enough so you can feel movement is all 3. Then you start making the adjustments in the sequence according to the shop manual.

I calculated my ounce inch measurements from the spring scale loads described in the manual and the distance I measured from the center of the steering wheel to where the spring scale is connected in the picture. I multiplied by 16 to get ounce inches.

The final adjustment you will make is the lash between the sector and worm. You need to make that adjustment with the steering gear in the very center of the travel. That is where you should measure the effort to turn the steering wheel.

If the ‘39 gear is like the ‘37 and ‘38 the worm actually has a slight “hourglass” shape. The idea is to provide a tight mesh when driving straight. As you turn the worm the clearance will increase due to the geometry of the gear mesh. The “hourglass” shape compensates for the increase in clearance but only to some extent. So when the gear mesh is set correctly for straight ahead there will be more clearance when off center.

I've been using both my shop 1939 manual and a 1942 Motors manual. The Motors manual says to use the 1938 procedure for the sector shaft and worm to sector adjustment and the 1940 procedure for the worm lash adjustment. It does distinguish between the Master (straight axle) and the Master Deluxe (my car). I've always used rear axle gear lube in my steering boxes. I have NGLI 0 that I use in my Model T universal joint. I can try that. The box is dry as it is on my bench, so maybe that is some of the problem. I still want to check a few surfaces, maybe there is a burr or a bump that I can not see. I appreciate all the help. Thanks, Mike

Hi Mike,

You are on the right track. I agree that rear axle oil will work fine in a steering gear. Except it will eventually leak past the bushings on the sector shaft. There is no seal on these old boxes.

Some of the people on this forum make there own steering gear lube. They mix NGLI 0 or even NGLI 2 with gear lube. They make a mixture that flows like honey or regular applesauce (not the chunky kind that I like). That means it will flow between the gears and into the bearings and bushings but not leak out very quickly.

If the ‘39 box is like the ‘38 the main difference is that the Master Deluxe uses ball bearings in the sector gear while the Master has needle bearings and a couple of thrust washers. Based on the ‘38 book the adjustment procedure is the same for both models.