49-51 Mercury Steering Gear Box Repair
 

I am currently performing an overhaul of the steering gearbox on my 51 Mercury and I have questions for those who have done this before. The worm gear in my box is spalled out in the usual place for a high time box (center of worm). The worm gear for the Mercury is not to my knowledge being reproduced at this time. I have heard rumors that the worm gear for the 48-52 F1 type pick ups can be used as a replacement. Has anyone on the Ford Barn board used the P/N 7HC-3524-X replacement worm for a 49-51 Mercury application and if so, what all else has to be utlilized/modified to make it work?

I figure that an F1 roller gear kit would likely have to be used for the sector as well but would like confirmation on this if someone would be so kind.

Kerby

Re: 49-51 Mercury Steering Gear Box Repair
 

Repaced my worm gear (did not replace roller) with one from a pickup. Only thing was that the steering shaft did not have a keyway. Resolved the problem by cutting off the new shaft and installed the old shaft keeping the proper length. The keyway has to be clocked to the correct position. Used a coupler I got from Borgesen 3/4" bore. Held in place by two spring dowel pins.

Re: 49-51 Mercury Steering Gear Box Repair
 

So far I have compared the worm to one from an F1 pick up and found it to be very close if not identical. The key spline for the shaft even appears to be in the right place. I'm going to start contacting some of the Mercury parts vendors this next week to confirm the worm. Joblot will be the first on the list since they indicate that the F1 worm can be modified to work in there 49 to 59 Ford parts catalog. The F1 type two tooth sector roller is a no go for this project. It is just too small in diameter plus the 2-tooth factor. Hopefully one of the two three tooth roller gears that are currently available as reproductions will work in the sector. If not then I'll have to keep looking for good original parts.

If any one out there can help with this, it will save me some time for sure. In any case, if I find the right combo, I'll update the thread for other folks that might have to rebuild one of these gear boxes in the future.

Kerby

Re: 49-51 Mercury Steering Gear Box Repair
 

The worm gear and shaft that I used did in fact come from
Joblot. The only ones that they had at the time had the later splined shaft. That's why I cut it and installed the original shaft.

Re: 49-51 Mercury Steering Gear Box Repair
 

Thanks 51 Merc-CT. Your input at least confirms this will work as far as the worm gear is concerned. I've got a pretty good press set up here at the shop so I'm going to get one of the new replacement worm gears and press it on to the original shaft. I'll try to get a piece of chrome moly or black steel thick wall tube/pipe just a little bigger than the shaft to keep it straight in the pressing operation.

I see the sector gears on E-pay now and then so I'll try and pick one of those up that way or just get a complete steering box. I will need to know what the sector roller shaft pin size is and mine is still good enough to go for now. I have another 51 that may need this work done down the road and it's nice to have a back up plan.

Kerby

Re: 49-51 Mercury Steering Gear Box Repair
 

Rotor,
I've never done the job, but I've read in forum threads (here or HAMB or ShoeboxFords) that the gear needs to be heated pretty well before pressing on the shaft. There was talk about boiling it in oil to get an even temperature.

Re: 49-51 Mercury Steering Gear Box Repair
 

I had contact with James at Joblot and he mentioned that indexing might be the only problem with use of the F1 worm gear. I'm going to purchase a new one to see if it will index differently on the Mercury steering shaft. If it won't work on the Merc, it will for an F1 box I'm saving for an AV8 project.

It seems the roller for the sector is different than the two three tooth sector roller & pin kits available from the early Ford parts sources. Gemmer may have used this for a few other applications but no new reproduction parts are known to be available at this time. In the mean time I may have sourced some serviceable used parts for this particular project.

Thanks to all contributors
Kerby

Re: 49-51 Mercury Steering Gear Box Repair
 

Kirby I have a 49/53 Mercury steering box has nos worm gear and sector. Not cheap if interested let me know.

Re: 49-51 Mercury Steering Gear Box Repair
 

Huff
I found an NOS one and have installed it with good success but thanks for the offer. Having one that is already on the shaft saves a lot of time replaceing the worn out worm on the old shafts. FYI, the 49 thru 51 are an odd ball Gemmer unit that is similar to some of the truck units but not the same. The 52 and 53 use a unit that is different so you will have to specify whether yours is for 49-51 or 52 & later.

To update for anyone else out there that needs a worm, I purchased a new reproduction worm for the earlier cars and pickups that use the roller type sector and have found that they are in fact the same part. You can get one for the 37 to 48 Ford passenger/commercial vehicles or one marketed for the F1 pickups thru 1952 and they will work. You just have to find a way to get the old one off the shaft and the new one on. The indexing spline is in the same location for all the earlier ones and the 49 thru 51 Mercury.

Kerby

Re: 49-51 Mercury Steering Gear Box Repair
 

Good to hear you got a nos gear. I was not in a hurry to sell my steering box but though it would help you out. Huff:)