[trammway]

Guys, this is not that much of suspense, we have more to come. I have finalized to choose the material in fabricating the spacer, a hardened metal tube which has got the inner dia matching to the stock spacer and had enough thickness, at first cutting the tube itself became a tiresome job, the CNC lathe really cried when the tube was cut into relative size. The picture shows the raw material used for making the spacer (unfortunately I couldn’t take pictures while we were standing on the CNC lathe)


After cutting the spacer was grinded well with a filer to make it smooth, then the spacer to match Mahindra Classic’s specification came out well.


Those who are looking for measurement details, I will leave the vernier caliper pictures with the newly fabricated spacer.




So, in order to fix the new spacer I have decided to replace the stock oil seal. The pictures below shows the old and new oil seals along with the Herm provided spacer and custom made ones.


This is how the PTO port looked after removing the oil seal from main drive shaft.


The next step in the process is to install the new oil seal; we need to use a flat pipe to press the oil seal into its position. A gentle hammer hits were required.


Same procedure is followed while we pushed the newly fabricated spacer.

Hurray the custom fabricated spacer fixed properly now, the actual planetary gear needs to be pushed in now.


Our very first attempt after pushing the new spacer showed a perfect fit.


Video of what has been explained above is for your pleasure.

http://www.youtube.com/watch?v=YWHogbua5LQ

Please note that I had to face my 2nd road block in here. What is it? Keep guessing…

to be continued…

[U.B.Singh]

Hello Siva,
I am happy you have started installing the Herm made Overdrive for the T18.
I am also at a loss to understand what is going on here?

You have shown pictures of T90 joint pinion versus KMT90's in your post no 207. You quoted ... "Look at the following figure which shows the old main drive gear next to mahindra classic, the dia of the front portion is not matching to each other. The same goes with MM540/CJ340 main drive gear, hence the herm's spacer that came with OD kit is of the older MM540/CJ340 model transfer case".

Do you claim that the MM540 and CJ340 came with the old style 6 teeth joint pinion, and the Classic with the 15 teeth? Please re-think friend!!!
BTW your Classic joint pinion is deprived of the PTO enabling teeths ( not that it will be used anymore after the new setup is completed).

In you later posts a lot has been spoken about that something called 'spacer'
Do you want to claim that the so called spacer if matched with the oil seal, will actually seal the gear oil from entering the transfercase?
If so then take an engineer's opinion.
The height of the 'spacer' maintains the alignment of the gear to be mounted on the main shaft with the counter gear at the transfer case only. Sometimes thin shim washers should be used for accuracy.

Please study the machine and not play around like a toy. Read the manual well enough, and look closely at the tapered end at the top of the custom made gear in post 207 with w-29.
Could it be intended to rub against the oil seal and stop the loss of gear oil to the t/c.
Could the manufacturer be recommending a specially designed oil seal for this?
Have the designer provided enough ways to lubricate the planetary gear set sitting right on the top end of the t/c, where the oil level is below the middle only.
Have they asked for a newer oil level? Or any special grade lubricant.

Many of these answers will educate people like me about what is going to happen under your passenger seat when that special OD lever is engaged.

With you always,
yours.......................................... UBS

[trammway]

Sir,

It is my privilege that you have raised the queries and I'm sure no one can provide better education than you.


1. PTO Joint pinion:

What you had said is correct about the joint pinion gear, it is actually Willys jeep's, I have explained the same in post #197. I was only trying to explain that the joint pinions have many differences including the ones came with CJ340/MM540 when compared to Mahindra Classic (stated by the mechanic. After you have raised this question now I'm looking for transfercases which came with CJ340/MM540 to validate his claim). The reason I believed him is because Herm has sent a unit with a spacer which suppose to be proper fit but in my case it is much smaller to fit.

2. Spacer

I see your point here sir. Thanks for the same. But my doubt is if the spacer need not be tight on the oil seal then why did the joint pinion's extended part fixed tight in the stock setup ? Just to answer this question I have fabricated a spacer to sit exactly the same way. Also at my first attempt the planetary gear was pressing/compressing the oil seal too much without the spacer and if I install the spacer Herm provided it was creating a shake/rattle.

3. Lubrication to planetary gear

The planetary gear's oil lubrication is of the same way like the drive pinion and the bottom part of the planetary gear is submerged with the transfer case lube. In fact the oil spalashes created by planetary gear assemble will be routed to the rear part of OD using a scoop.

4. PTO enabling teeth

Sir, I wish to quote your post "BTW your Classic joint pinion is deprived of the PTO enabling teeths ( not that it will be used anymore after the new setup is completed)." I had a shock when we removed the existing Joint Pinion or drive gear as it didn't have the PTO enabling teeth. I assume Mahindra would have thought why to provide the PTO teeth when there is no PTO accessories available in Indian market. Please see the below pictures and correct me if I'm wrong.




Also I assume after installing the Overdrive, I will be re-enabled with PTO teeths as it is available in the rear part of the Overdrive. Please refer the previous post(#180) http://www.team-bhp.com/forum/1628612-post180.html made by Santhosh with pictures.

I'm sure my understanding may be completely wrong, hence just to make sure I'm not messing up anything, today I will get the gearbox down and will see if any damages have been caused.

Thanks for all your valuable inputs sir, Greatly appreciated.

[vinod_nookala]

Very interesting installation! All the best for your maiden attempt. Lot of learning here.

[Tejas@perioimpl]

Siva,

I just forwarded this link to herm. He replied back asking you to get in touch with him.

[trammway]

Originally Posted by vinod_nookala

Very interesting installation! All the best for your maiden attempt. Lot of learning here.

Thanks mate.

Originally Posted by Tejas@perioimpl

Siva,

I just forwarded this link to herm. He replied back asking you to get in touch with him.

Yes, I have already sent him an email and waiting for his reply.

[trammway]

Dear Friends,

Just happen to have an email discussion with Herm Tilford who actually mfg the Overdrive. I'm posting his email without any editing, for your better understanding.

From: Herm Tilford <hermtheoverdriveguy@yahoo.com>
To: Sivakumar Balasubramanian <siva_kum@yahoo.com>
Sent: Tue, March 16, 2010 8:45:29 PM
Subject: Re: Installing the Mahindra 29teeth 15spline OD

Hi Siva,

That is an excellent video. May I have your permission to put the complete video on my website when you are finished with it. It would be very helpful to others.

A couple of items that I need to address.

I imported a complete Mahindra transmission and transfer case from England to have a prototype assembly to build the overdrive for the Mahindra.

The seal:
The seal interferred with the barrel assembly fitting properly so I removed it. There is a oil hole that transferes oil between the transmission and transfer case when in operation. so the seal can be used or not and also through the bearing. I find that when going uphill the oil travels to the rear and uphill it travels forward sharing the oil

The spacer:
The spacer is the correct length that is needed in order to have the correct amount of threads for attaching the barrel gear on the mainshaft. The spacer (part with allen screws on the front of the barrel gear) is machined smaller than other overdrive applications because it has to clear the inside of the transfer case. The barel gear also has to be at a certain depth and stickout to allow the rear assembly to properly engage. Now there is a pack of shims with the overdrive. These shims are to be used incase the overdrive jumps out of direct when in operation. If the overdrive does not jump out of direct do not use. If the overdrive does jump out of direct then shims need to be added to move the barrel gear to the rear to better engage the overdrive into direct.

Torqueing the drive nut:
Start the torque at 75 foot pounds and increase from there at about 5 pounds at a time. Do not back off to set instead start over

tab washer:
Make sure the tab is lined up with one of the machined areas that it needs to be inserted into to lock the drive nut (star nut) to the shaft.

square lockwasher:
Using a long screwdriver to push the side of the snap ring into the groove will assist in not compressing and distorting the snap ring.


Transfer case seal.
I have misplaced the origional seal. I could make the spacer larger to fit the original seal but it will not seal because the oil will travel back and forth along the splines anyway

If you have any other issues please let me know. I want a good quality product and ease of installation.

Again I compliment you on a fine video!!!

Regards

Herm

[JeepCaptain]

Originally Posted by trammway

Dear Friends,

Just happen to have an email discussion with Herm Tilford who actually mfg the Overdrive. I'm posting his email without any editing, for your better understanding.

From: Herm Tilford <hermtheoverdriveguy@yahoo.com>
To: Sivakumar Balasubramanian <siva_kum@yahoo.com>
Sent: Tue, March 16, 2010 8:45:29 PM
Subject: Re: Installing the Mahindra 29teeth 15spline OD

Herm

Siva, Good to hear from the maker itself. I did not understand all the content/technicalities herm mentioned since I dont have the OD infront of me. But tell me does this mail clears all your roadblocks?

As Herman mentioned I am also eagerly wating (I am sure there are many more like me in this forum) to see a quality product with ease of installation so that I can place my order with Herm .

Tell me, do think this would have been a direct bolt on installation if it was done on a CJ3B with Warner T90 GB and Spicer 18 TC??

[trammway]

Originally Posted by JeepCaptain

Siva, Good to hear from the maker itself. I did not understand all the content/technicalities herm mentioned since I dont have the OD infront of me. But tell me does this mail clears all your roadblocks?

As Herman mentioned I am also eagerly wating (I am sure there are many more like me in this forum) to see a quality product with ease of installation so that I can place my order with Herm .

Tell me, do think this would have been a direct bolt on installation if it was done on a CJ3B with Warner T90 GB and Spicer 18 TC??

My road blocks were already cleared. I'm only posting the installation report , and explaining all the possible issues one may face while installing the OD.

I'm giving him some inputs which may help him improve the OD for Mahindra, as I have addressed them while installing on my Explorer.

Willys MB/Ford GPW/Willys CJ3B have two combination of main drive tooth and spline counts and other items are already known to many US citizens / garages. Also the original Warn and Saturn products were designed with the intention to be installed on original US make Jeeps. So I'm sure they will fit properly if you have the US spec jeep.

I'm still not sure of the Mahindra CJ3B and other version of Jeeps in India as the main drive gear and oil seal specs needs to be validated before commenting on your query.


Now another update:

I have got the gearbox down from Jeep to see if any damages have been already happened. But for my luck, all intact.

I did this for 2 reason, one to make sure the OD didn't cause any issue and 2nd one to change the bearings which I had it in y TODO list.

Though internally no issues other than the worn out bearings and a counter shaft, but I found my transfer case mounting ear had a crack and while we removed the transfer case it was broke. Hence I'm going for brand new transfer case housing of Mahindra make.


Arrow shows the cracked area and the circles shows the pieces broke out from the cracked area.


Rest of the pictures below shows the gearbox/transfer case being dismantled

[vinod_nookala]

Siva,
Breaking of transfer case shell is shocking! I have heard Arka saying about this but why did this happen on your vehicle? Usually happens in old transfer cases due to excessive wear and tear. Further did you have gear slippage problems in your TC? Due to crack on the shell the gears develop lot of play. But when i drove your jeep almost a year back your TC was so silent. How come the shell broke? Any pointers?

Plus why did you remove your main gearbox as well? Why did you dismantle it?

[svsantosh]

Originally Posted by trammway

..but I found my transfer case mounting ear had a crack and while we removed the transfer case it was broke. Hence I'm going for brand new transfer case housing of Mahindra make.

1) How can a TC housing break? Does that mean something inside was loose?
2) Wont this size a crack lead to a huge oil leak?
3) How expensive is a new/used TC housing?

[trammway]

Originally Posted by vinod_nookala

Siva,
Breaking of transfer case shell is shocking! I have heard Arka saying about this but why did this happen on your vehicle? Usually happens in old transfer cases due to excessive wear and tear. Further did you have gear slippage problems in your TC? Due to crack on the shell the gears develop lot of play. But when i drove your jeep almost a year back your TC was so silent. How come the shell broke? Any pointers?

Plus why did you remove your main gearbox as well? Why did you dismantle it?

The crack is only on the ear which is used to mount the transfercase, hence it is surely not because of usage. May be something else such as mechanic used hammer, some rock /stone hitting, really defective etc. The main thing is that the cracked area looked like the crack was there for long time and no fresh breakage signs, see the picture you will understand it had lots of rust in that area too.


It just that I have felt bit excessive shake in both the main shaft and also the drive shaft in the PTO port. So I was sure the bearings needed attention, as I'm opening the gearbox I thought of changing them all. They were now clocked more than 80K kms I guess.

After dismantling I found most of the bearings got physical wear & tear marks hence replacing all the 6 bearings and one of the counter shaft. (this is just a regular maintenance and the first time I'm doing it my jeep it is almost clocked around 35K in hands)

The gears (TC and Tranny) never slips but I do have some noise while in idling, also slowly it is becoming hard to engage gears ( not very hard just bit harder than before)

Originally Posted by svsantosh

1) How can a TC housing break? Does that mean something inside was loose?



2) Wont this size a crack lead to a huge oil leak?


3) How expensive is a new/used TC housing?

Not the housing but the ear which used to mount the TC, so there is no damage in internals.

Luckily no, as the cracked part was attached to the transfercase and also on top side of it (bottom left side).

Brand new after market is Rs. 1500ish range, company stuff may cost a little higher. Used ones are at 500-1000 range.

[trammway]

Guys,

I'm still in the lookout for transfer case shell, I found the original one is costing around 4K and no avail. So I was shifting my search at used ones, and found the TC shell also got minor changes. Please see the pic below and let me know if this will create any issue in terms of lubrication to the bearing ?



The one which didn't have oil channel and having less height on the mating area is also from MM and removed from a old MM540.

[trammway]

Finally I got a brand new body shell for my explorer's transfercase, it is a original M&M shell and costed me around Rs. 4,500/-

[JeepCaptain]

Originally Posted by trammway

Finally I got a brand new body shell for my explorer's transfercase, it is a original M&M shell and costed me around Rs. 4,500/-

Good find Trammway!!
Now put them together and get your Classic back on the road ASAP .
We all are waiting for that test report which shows your speedometer which reads 120 kmph or more on highway.

I am sure Herm is also waiting.

Cheers
Shibu