OK. I have a technical/DIY question for anyone who can help. I have a '39 Mercury dirt track stock car that I am trying to change the rear-end gear in. It currently has a 3.78 rear end in it (I think....34;9....or it might be a 4.11...37;9). I am changing it out to a 6.66 gear set up (40;6) so we can run it in third gear. Does anyone know how to adjust the backlash/spacing on the gears? I have never done this before, so forgive me if I seem like I don't know what i'm talking about...because I don't! I have heard/read some places that the gears need to be set up properly otherwise they will just burn up. Can anyone help me with this? I shure would appreciate it! Cheers, Glendon P.S. I'll try and post some pictures soon so you all can see what I'm working on.
your side shims control backlash and your pinion shim control pinion depth. you need to have proper pre-load on the pinon bearins also or you will burn those up. contact randys ring and pinion and get all your specs and they can help you out too.
It would be helpful if you could gain access to an old MoToRs Manual (one that covers '48 or earlier Fords). It has pretty comprehensive section on reassembling a banjo rear. It ain't easy.
Ive done many, and hes right. It ain't easy. If you have done several, its easy (or looks easy) but it ain't for beginners. Even when you have all the bearing and gears in front of you and think you can do it, DONT. I learned from a old guy that worked in a Ford dealership when they were new. He had tricks, that were unreal. But he did not show me, he told me, explained, and the first one I did had a used pinion and ring gear from two rears. He EXPLAINED how to do it and not have it come loose after 5-10,000 miles. Quiet as a mouse,I was blessed cause I never did one that went bad, but I don't think I could explane it like he did. I often wish I had some one to pass on what I learned from him. I'm seventy now and ain't no young ones want to learn the old way. Such a shame. Ice man
Here it is. Unfortunately the pics have disappeared. It is not as hard as the others here are saying. I just did it 2 days ago using this thread as my guide. Admittedly I did have a printed version from a couple of years ago with pics. http://www.jalopyjournal.com/forum/showthread.php?t=61502&highlight=setup+banjo It does take a fair bit of time. I spent maybe 5 - 6 hours on it, but it was my first one. Really not that hard.
Where did you get your parts from? Did you buy a rear-end repair kit with gaskets, shims and seals? What about bearings?
I didn't do the bearings. When I got it apart the carrier bearings looked new. I just bought a gasket / shim kit from one of the local suppliers here in Oz. I imagine you could get them from Macs, Sac Vintage, Hotrodworks, Speedway. You guys have plenty of suppliers of early Ford stuff. PM me if you have questions. I'm no expert but at least I've been there. Pete
Isn't getting the carrier shimmed correctly half the battle? If you didn't have to mess with the bearings, you probably missed out on much of the fun. Take one all apart, use new bearings, then tell us it only takes a few hours.
Hey all! I have an update! I have been moving along quite slowly on my rear-end rebuild as I only get a weekend here or there to work on it...and the fact that the car is 40 miles away. It gets expensive driving up to work on it every weekend! Well, I got the rear-end all torn apart. Here are some pictures: And once I took the drive shaft housing off, I received the shock of a lifetime...the drive shaft and the pinion WERE ALL ONE SOLID PIECE: There was a problem. Luckily, 30 years ago my grandfather had planned for a broken drive shaft and had purchased a replacement which didn't have a pinion made on to the end of it. It was a shaft with 6 splines on both ends. So, I had to pick up the phone and order a 6 spline-to-6 spline coupler to join the new pinion to the drive shaft (notice how small it is!) After all that ordering and shuffling around, I have now got it all back together! Just a DIY tip...when putting your new race into the center housing for the pinion, it makes it SOOO much easier to put that race in the freezer for an hour or two, and then heat up the race seat with an oxy-acelylene torch just a bit. It literally drops right in! No pressing! God, I am glad this is over! I will let you guys know how this new 6.17 gear works out! I'm looking forward to the line jumps with it!
Sure! Here are some pictures: She was in our garage when it burnt, so its not that pretty. We have lots of painting to do, I still have to replace the seat and some guages, and I also have a fuel cell to replace the old Johnson Marine outboard gas tank! I still have a little bit of work to do.
She's not pretty, but man does she sound mean! I absolutely love the original flatheads! I have a very special spot in my garage for her!
Your original post indicated that you weren't sure (didn't know?) what ratio was in the rearend to start with. Now that you have it apart and have posted pictures, you've confirmed that it is, indeed, a '39 Merc: witness the one piece pinion/driveshaft. Now comes the real question: Since it's apart (I know--you aren't interested in what came out of it.) have you counted the teeth? It should be a 3.54:1. Let us (me) know-I might be interested.
I couldn't agree more! When it was built, it was sitting (rotting) in an old chicken yard. My grandpa saw it, inquired about it, bought it, and turned it into a race car back in the 50s. It would have made a BEAUTIFUL resto-mod! But, racing brought in the money back then! Dale, the gear that was taken out of the rearend was a 3.78 (9/34). I would not want to part with it just on the off chance that I would need to put it back in the car (because it has the driveshaft/pinion all-in-one). I DO have other ring/pinion sets laying around, but they are all either 4.11s or 3.78s too. I don't have a single 3.54 at home. I know those 3.54 gears are hot with you street guys! If I find one, I will let you know. I have lots of extra drivetrain parts laying around! BTW...do you know what tooth combo a 3.54 would be? I'll have to do some counting!
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