T9 Leak and Fluid

[480rider]

I suppose I'd better introduce myself before launching into a question, especially in my first post! I joined this site a while back, but so far have been just reading and learning. Thanks to everyone for the technical and other posts -- they have been very helpful in my understanding of my new car.

 

I recently acquired an '02 Caterham "America," which is the car produced specifically to compete in the SCCA E Production class. It has the SVT Zetec and Quaife/T9 5 speed. I've only had the car for a couple of months, and have been itching to get to the track and drive it. I finally got out last weekend, and managed a first in class in my very first race. Gotta credit that to a great car!

 

Anyway, after this first track weekend, I noticed a substantial amount of transmission oil sprayed all over the tunnel and underneath the floor pan. I've managed to trace it back to a leak from around the cap situated behind the shifter, at the very top rear of the gearbox. (I'll call this the shifter "box," as it appears to be walled off and separate from the main gearbox.) This "cap" (I don't know what it should really be called) is about 2" in diameter, and appears to press into the back of the tail housing without a gasket. There is a small lip in the case at the bottom of the area where the cap presses in, which is where the oil was leaking out. It appears to be there intentionally to allow for breathing or seeping of excess oil -- it does not look like a chip or break in the case.

 

I checked the oil level at the fill plug, and it's up to the bottom of the plug. The shifter box still has a lot of fluid left in it as well. It appears that the last time the gearbox was serviced, the shifter box was filled with transmission oil, and that excess (?) oil is what has leaked out.

 

My question is this: Should the shifter box have been filled and kept filled? If so, should I seal up the lip at the bottom of the cap so that the fluid does not leak out again? I've searched to find information about this gearbox, but with little success. As the shifter box is not open to the rest of the gearbox, it appears to me (novice mechanic, at best) that it should be lubricated by a heavier grease, rather than transmission fluid, and that the two would not necessarily mix. This would explain the lip/opening at the bottom of the cap -- if the shifter mechanism is lubed by grease rather than transmission oil, a small opening would not allow the grease to spill out. I'm not sure this makes any sense, hence my question.

 

Does anyone know these gearboxes, and have any advice for how this part of the unit should be lubed and sealed? Thanks in advance for any replies/advice.

[MHKflyer52]

Well I will take a crack at your question for you.

1. Can you post a photo of the plug and the area were the oil leaked out.

2. I would think that there should be some room for expansion of the oil / lubricant in the shifter box as there is in the gear box. I would keep the oil / lube just below the vent on the plug if it were me.

3. You can always add a breather to the top of the shifter box with a catch can.

4. I would clean the area and go for a nice drive or run a couple of practice laps and then see if the oil / lube is still leaking out of the shifter box with the oil level below the vent in the plug. If it is I would then look into sealing it up and adding a vent to the top of the shifter box.

5. You might want to contact the prior owner and see if that person has any info on the setup and what the proper fluid / lube should be in the shifter box. I have a Miata and the shifter has gear lube in the shifter tail housing to lube the shift mechanism which I suspect is the something that your application is doing.

Just my ideas and hope they help and WELCOME ABOARD and post some photos of your ride for us to check out.

[480rider]

Martin:

 

Thanks for the reply and the welcome. Due to the small space around the tunnel, I've been unable to get a decent photo. This link is the best schematic I've found of the T9: http://www.madabout-kitcars.com/articles/imagePage.php?imagesrc=type-9-gearbox-cross-section.jpg&imagealt=Ford%20Type%209%20cross%20section%20diagram&credit_to=&credit_to_www=)

 

The cap I'm referring to is the round piece (cut in half for the drawing) just above the output shaft. The image makes it pretty clear that the shift mechanism is housed in its own box, pretty much separate from the rest of the gearbox -- this is what made me wonder if it should have transmission oil in it at all. As for the lip in the case (possible breather), it's located at the very bottom of the cap, so fluid will continue to drain out unless it's sealed completely.

 

I'll post up some photos of the car and more specs soon.

 

Thanks again,

 

Troy

[MHKflyer52]

Hi Troy,

 

After looking at the cross section of the transmition I would say that that area should be dry and the componets lubed with grease (white grease) but that is just my belief.

I think someone that has a t9 in their car would beable to answer your question better and will most likely post a reply soon to help you out and educated me on the t9 transmition.

[blami]

Hello,

 

I have the type 9 box in my 93 Caterham HPC.

 

If the box is properly filled, there should be no trans. fluid in the area that you are describing. None what so ever, not even close.

 

Since there should be no fluid in that area there should be no leaks there.

 

I have found it best to both drain and fill the gear box by removing the top inspection cover (it's shown in the cut-a-way diagram). Remove the 10 bolts holding the cover in place--access available from the engine compartment, skinny hands help. There will be a fiber gasket between the cover and trans. top. Note how the cover fits. There is a built in vent/breather-- it looks like a 'blister' with a small pin hole in it. That is all the venting that you need---you can drill or tap a more robust bleeder and run a tube to a catch tank BUT you will pump out an amazing amount of fluid into the catch tank under race conditions (ask me how I know). Stick with the standard 'blister' vent but make sure that it is not plugged and as tempting as it may be, do not overfill.

 

Bart

[MHKflyer52]

See Troy (480rider),

I told you someone with the T9 gear box would post the answer for you.

[slomove]

There are some T9 vintages (I believe the older ones) with high fill hole where the oil fill level is 1" BELOW that fill hole/plug. If filled up to the hole they may spill oil somewhere. I remember a discussion thread about that but don't know anymore if on this forum or somewhere else.

[480rider]

Martin, you were right on. Thanks for the replies, Bart, Slo. I've got a message in to Ben at Caterham USA. Hopefully he can help me with the proper level question. I have noticed different info on just how close to the plug it should be.

 

As for the shifter area, it certainly makes sense that it should be free of transmission oil. I suspect the last time it was opened the mechanic thought it should be filled.

 

Now I just have the engine leak to deal with!

[wemtd]

480rider,

I'm intrigued, having a T9 in my own (ongoing) S3 build.

Have you been able to remove the shifter (from above, 3 bolts on my trans) to inspect the area oil is presumably coming from?

 

paul

[480rider]

I did. I found the shifter box appeared to have been filled with transmission oil. While no longer "full," it was certainly coated with the same color and consistency of fluid as I found in the main box. I should have mentioned before that the seller told me he had a problem with the shifter, and had recently replaced it with a new one. This would explain why his mechanic had opened the box and filled it with fluid. Their theory may have been that the prior shifter failed due to lack of oil, and filling it would keep the new one from the same fate. (Just my speculation.)

[11Budlite]

I agree with Bart that there should be no fluid in that area. Perhaps someone thought that was a convenient way to fill the T9. I decided to check it so I just pulled the gear lever off the top of my T9 and there was no fluid at all in the shifter housing. When I rebuilt my T9 that 2" cover on the back had to be removed to dissy some of the shift linkage and when I reassembled it I just put a small bead of RTV to seal it just in case.

 

Here's a link to a T9 manual (N-type): [url=http://biggles.net/download/Manual_Type9.pdf][/url]http://biggles.net/download/Manual_Type9.pdf

 

Here's a photo of the fill side of my T9 before I reinstalled it showing the relationship between the fill hole and the shifter housing.

Edited May 1, 2010 by 11Budlite
spelling

[S1Steve]

Bruce , Thanks for the biggles manual link.

Steve

[480rider]

Thanks for the replies, and especially thanks to Bruce for the pic and link. I'd been searching for a manual or build guide, but had come up with nothing. Your link helps a bunch.

[MichaelD]

I have posted photos and specs to the various T-9s here:

http://www.topdocsracing.com/pdf-links

 

This T-( is nor for sal. It has standard ratios and the correct input shaft fo a birkin.

[MichaelD]

l almost forgot. There are also PDFs for T9 and other Ford gear boxes.

[480rider]

Michael:

 

Thanks for posting the info -- it has helped me to sort the issue. With the shifter box cleaned out and lightly greased, my gearbox shifts smoothly and no longer leaks.

 

After a conversation with Ben at Caterham USA I changed the fluid (from where it's supposed to be) to Redline MT-90 (he recommended Redline MTL, but I decided to go to MT-90 for my track-only application), and it seems to be working fine.