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Gearbox rear seal

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VelodromeRacer

VelodromeRacer

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Having a new to me 1959 vintage Bugeye racer I need some help. I took the car to the track last Friday to shake her down after new suspension upgrades and I have found that it looks like oil is leaking out the tailshaft of the gearbox.

The car has a 948 engine with an upgrade to the ribcase trannny. I need help in what I need to do to get this leak fixed. Can I remove the driveshaft and repair it without removing the engine? (The car has access cut from below)
Is there a rear seal that will work for this? I see that Moss sells a bushing and a rear seal...any use?

Thanks
Velo
 
Yes it can be done without removeing tranny.

I don't remember details but here goes.

Pull drive shaft.

use a large screw driver to remove the oil seal down through the shifter hole in the tunnel. May take a bit of knocking.

Replace by reaching up into the tunnel from the rear it is a push to fit.

Not easy at all, hope your arms are long enough.
 
The rear seal is <u>55</u> in the image below.

To be honest, it's <u>not</u> really a great design and will leak if the gearbox is even just a bit over-full. Especially under racing useage.
Sometimes, just sitting on a tilted trailer overnight will make these seals leak.
Be <u>really</u> sure that it wan't overfilled before you rip it apart. Drain fully and re-fill with normal motor oil (10W-30 or similar is fine). If fact, leaving it just a bit low might be a good idea.

Anyway, if you really feel it need replacing, I would try the same thing Jack has suggested


SPM-025.gif
 
But a screwdriver and a hammer will do the trick.
 
Might not be too bad since there is an access hole cut in the bottom of the car.
 
Yes but if memory serves me correct it is not very large 4x6?

I agree with Jack and Nial. Check the fluid level first and if you do need to change it, be patient. I like using a large socket for tapping the new one on with.

Pat
 
Great tricks, I will look into all of them.
I have pretty good access from below...Would there be an issue that this 948 engine has a ribcase hooked up to it where I may have a midified ribcase tranny?

Also, I ordered part number 55 as shown above, what about part number 54, the bushing...is that something that gets renewed? It seems that even the racers still run engine oil in the gearbox and not something else for high heat?
 
One little tip if you don't plan on draining it first. Jack up the rear of the car so the oil doesn't pour out when you pull out the driveshaft. If its already leaked out a bunch, may not be a problem.

Glen Byrns
 
The only modification these trannys normally get is a set of Jack Knight gears. That has no affect on the rear seal. However a loose / worn bushing could allow the driveshaft to sit at a slight angle and give a bit of leakage. The bushing isn't easy to change. Best off with another tailhousing in newer condition.
 
Rear seals cheep, give it a go.
 
I pulled the driveshaft after draining the gearbox, and after I checked to see if it was overfilled. The seal is a PITA...what tips to remove it? Mine looks like it is a big copper piece..but it is not budging and since I also removed the existing seat to fit a Sparco seat, I am done for the night.

I hope to try again tommorow evening.
 
If it is correctly installed, it's staked on in three places. I usually cut a small slot in them to remove, and then re-stake after installation. I'll bet if and when you get it changed, you'll find that it would have been easier and quicker to have removed the engine and tranny in the first place.
Jeff
 
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