Hewland overhaul-estimate.
I have an RF75 Van Diemen that has a very noisy transmission which also leaks oil from the front seal. The oil is dripping out of the bell housing and yes it definitely is gear oil.
Anyone care to give me an estimate what an overhaul will cost DIY or professional job.
Anyone have a Mk 8/9 for sale, cheap (relatively speaking!).
Thanks.
Keith Averill
It will vary widely in cost, largely depending on what is causing the noise. If the noise is just a bad gearset, then the cost is a couple hundred bucks for a new gear and you can change it yourself. If the noise is the ring and pinion, then probably a couple of grand to buy one and have it installed. It's hard to diagnose without seeing it. The input shaft seal is a few bucks and you can change it yourself if the box is out of the car.
Brian
Hewland o'haul
Input seal, not very expensive. The possibility exists that with a gearbox that old, you might find the input shaft worn where the seal has ridden all these years and it may need to be replaced.
Noise, hard to guess. While being driven or just sitting there with the engine running ?
Particularly in one gear or all of them ? Throw-out bearing or clutch bobbin ?
The brass shift forks (3) wear and need replacement over time, reverse gears (3) get beat-up and will shed metal, selector shaft (hockey stick) bushings wear, things like that.
All these issues (and more) contribute to the cost.
Thanks for input (pun intended) I'll post again when I have the box out.
rf 75
can you post a pic of your rf 75 ?
what is your chassis number ?
I have one in australia
thanks
mal
If you are going to strip the gearbox down out of the car, it's always nice to loosen the shaft nuts before you take it out of the car. It's a right pain wresting the box to try to get the torque on the nuts to undo them if it's not held in a handy jig (ie, you made up a transmission mount for your engine stand, or put it back on it's mounts in the car). Also, when stripping it down on the bench, once you take the long draw bolt out of the layshaft, the input shaft can fall out the front quite easily, it's held in by that long draw bolt.
Brian
If you are going to remove the pinion bearing, loosen that nut while in the car as well.
But that does take a very special "socket" and since you are having it rebuilt whoever you choose would have the correct tools and holding fixtures. Might be a good idea to send it out with all the gears still installed to allow a more complete set up and confirmation of correct operation with the gears you are going to actually use.
A little late in reporting but some items of interest; a lot of the noise was caused by the pinion bearing securing ring (the one that needs the special VW tool) being loose and rubbing on the crown wheel !!
I replaced the clutch shaft seal and two needle roller bearings and put it all back together. I added my own design of 'o' ring seal to the selector shaft and so far no leaks. It's still a pretty noises gearbox but it's staying together.
I have completed 4 races (would have been 5 but some idiot in a FV punted me off at first turn! Apparently he needed my brakes to help him stop). Not the fastest thing on 4 wheels (me or the car) but not the last FF out there either.
The car has not been raced in 26 years so I'm calling it a successful return to competition!
Thanks for all the input, always find some worthwhile posts on Apex!
To the FF guy in Australia; my RF75 is chassis #011. The Hewland is H-759.
From what I've heard?
Find local help. Save $$$
Keith, why not ask Al Ores. Someone must know his local number if he's not vacationing at his place somewhere near Whistler. He's retired and if he does not wish to do it, perhaps he will know someone who does in the greater Vancouver area. Also, perhaps Marty Knoll could recommend someone.
Albatross; the Hewland is working fine, it's just old and noisey (some what like the driver)!
I do all my own work then I only have one person to blame for the screw ups!!
Mr Rizzo; you are suggesting there is more than one side to my story?!! :-)
He asked for an estimate, that's my estimate. :-DOriginally Posted by Keith Robinson
Noisy gear box?
Keith, the usual people that work on the gear box and make a living at that type of work know that there are critical clearances that must be achieved when reassembly is being accomplished. You have strange noises emanating from that gear box? There is an old saying: "Do it right or not at all." That particularly applies to race cars.Club drivers work so hard taking the gear box out, (or engine) then work on it, reinstall and they wonder why they still have problems.
I remember the old adage "Noisy gears are happy gears"
john f
I like it!
Straight cut gears are by nature noisy and it changes gear just fine; I will have it apart to do a gear ratio change before the next race; I will report what I find.
So, a little late with the update!
The noisy transmission ran 6 or 7 races last year, worked fine except other competitors complained about the noise!
Took it apart and found nothing obviously wrong but decided to replace the pinion bearings anyway while I had it apart. Ring and pinion wear wasn't too back, backlash still within spec (.010"). Wear pattern looked OK, I checked with Prussian orange stuff!
However!
Upon re-assembly I have discovered there are two bearings available and the one I bought from the VW specialist (he said he had sold two to another local rebuilder/racer) has a larger rear tapered bearing and requires modification to the reverse gear hub! Of course I found this out after having re-installed the transmission into the car.
Pegasus does make reference to the fact that the bearing they sell fits like the original but I was going to save money, rrright. Going to miss the next race instead, grrrrgh!!!
Sounds like you found the issue though!
That's a positive!
Hewland
If I understand you correctly and you need to modify the reverse hub because the pinion bearing is different, then you will also need to do the same (or replace it) for the reverse slider gear.
I have heard that, what is the problem with the reverse slider?
Page 32 in the manual
http://www.hewlandclassic.com/assets/manuals/mk9.pdf
MK8's are a lovely bit of kit, but if not maintained and set up correctly any damage costs the same as the 3rd world debt as parts are priced by their weight in gold.
Reverse has a step on the back side so it will make contact with the reverse gear in case and not stop prematurely against the pinion bearings hub.
Wonderful, thank you!
Here I am thinking this is something new (because I've never heard of it and neither has my local FF mechanic) and it's been in the book for 20 years!!
As an aside; sorry about the World Cup, you almost made it! (I lived in England the last time you won).
Gotta love Apexspeed forum; this couple of days has been a great learning experience. Replies and help from FF's from all over, thank you all!!
This picture and page 32 say it all, thanks again!
Best wishes from the sunny West Coast.
Reverse has a step on the back side so it will make contact with the reverse gear in case and not stop prematurely against the pinion bearings hub.
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