Need Hewland transaxle information/help

[Paul Redstone]

I am rebuilding my Mark 8/9 transaxle on my 1969 RP-2 Royale. I have done later Mark 9 units and I have the tools to do this work, but there are some differences that on the early unit that I need help with.
First, the carrier bearings are ball bearings. Not just the outer ones in the side cover plates, but the ones on the ring gear carrier itself. I know how to set the preload on tapered bearings with shims, but I cannot figure out what to do with ball bearings. I did not think there even was a preload for ball bearings.
Second problem is that the pinion depth for the pinion gear is too far into the case. I believe there is suppose to be some space between the end of the pinion gear and the Hewland tool that is used to measure pinion depth. My pinion gear is so far into the case that you cannot get the tool completely in. There is no clearance. Furthermore, there do not seem to be any shims at all under the pinion gear to remove to make some clearance. I believe the actual pinion gear clearance is usually marked on the pinion. it might be .018" for example. Well the number on my pinion is 2.236. I do not know what that is.
The transaxle I have has the old four bolt arrangement to hold in the pinion bearings. Also, the only number on the case I can find is 113.301.103. The number 46 and 46-1 also shows up in other parts of the case. These numbers are part of the casting and not stamped on. There are some curiously small numbers stamped inside the bell housing. They are 3 1 39. Needless to say, I would appreciate any information anyone has about this transaxle. Thanks, Paul

[Earley Motorsports]

The number 113.301.103 is the VW number which shows the case was originally out of a 68-70 VW Bug. No help on the other sorry.
.

[Bob L.]

Not sure I have answers for you. Had issue on MK9 with Pinion depth and no Hewland tooling. Figured I could back out numbers by putting straight edge on end of pinion and referencing back to bore for side plate. Get to depth by calc, and numbers. Found mine was coming out too deep, but had run before I got it...... worried I wan't doing something right, so, gave up and finally sent to Williams. (You can do same to confirm depth, if tooling won't fit.....should have feeler gauge gap between tooling and end of pinion...work off centerline on diff.)

Paul confirmed depth was too deep, previous owner hadn't done it right....(faced with where to put it next.... we sort of split difference to keep prior wear issues to min. skewed towards factory numbers as pattern wasn't that heavy. who knows? So, far running ok..)

As to numbers, found this apex thread in my archives, with some notes on tooling...:

http://www.apexspeed.com/forums/showthread.php?t=21256

Followed by:

http://www.apexspeed.com/forums/showthread.php?t=77365

[FONT=Arial][SIZE=2]SAID 120 MM, 4.7" WILLIAMS SAID 4.71" 1/100TH DIFF..?

(never got clear answer to what tool should be..)

(Think Pegasus had some notes about number on web site..Hewland uses tool and feelers, Webster works from centerline or face of pinion shoulder....)

As to those ball bearings, never seen that...wonder if someone made change earlier, with other ideas? It's very hard to get angle contact brgs. to work right with preloads, angle contact rollers are best way......sort of think someone made an engineering substitution...but,....really don't know enough....?

You should call Williams and talk with Paul...found him a good source, knowledgeable, with humor....likes his tea.

Bob L.






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[kevskisps]

Hi, have you got the older MK6 box where you have to heat the side plates to get them off the bearings as the Diff is on ball bearings rather then when Hewland moved over to the MK8 where the diff is on taper bearings that separate when you pull the side cases off?

The MK6 output shafts should have a smaller set of splinds on them than the MK8, which is another give away.

I've looked but cant find any pics on the web, but can you take a pic of it?

[Paul Redstone]

First, thank you for those who responded to my query. I now think I have a plan; maybe? Also, to Messrs kevskisps in London. I will be happy to send you pictures of my unit, but as I am a techno clod, I do not know how to upload them to Apex Speed. I will gladly email them to you if you contact me at predstone@verizon.net. Thanks

Hi, have you got the older MK6 box where you have to heat the side plates to get them off the bearings as the Diff is on ball bearings rather then when Hewland moved over to the MK8 where the diff is on taper bearings that separate when you pull the side cases off?

The MK6 output shafts should have a smaller set of splinds on them than the MK8, which is another give away.

I've looked but cant find any pics on the web, but can you take a pic of it?

[Bobsy SR 6]

PaulIf the pinion is too deep (no clearance between tool and gear face) you need to ADD shims behind the bearing to move the pinion back. This will give the clearance you are looking for. The pinion should have the clearance stamped or etched into the face. Each gear is different.You can try contacting Scott Church at Scott@thegeardaddies.com or call him962-314-4119. He is a Hewland specialist.Tom