Outboard Drive Shafts - Availability or repair?

[stugilmour]

Got the verdict back from my mechanic late this afternoon. At least one of my outboard drive shafts is worn out where the outboard bearing locates. The bearing failed in quite spectacular fashion and is now shaft has too small an OD to locate the bearing correctly. The other shaft shows some wear as well, and he figures it should also be replaced. Haven't looked at them yet, but Malcolm is pretty sharp on this stuff so pretty confident they are past the Locktite solution. He prefers I source replacements if possible.

I talked with Dave Bean and he has none in stock, so about a month to get new ones made up. Have inquiries at all the usual suspects and waiting to hear back. Can anyone (either side of either pond ) suggest an immediate source? Really want to get the car back together for LOG32 in Orlando end of October. Time is getting short to get the car back to right, drive around a bit to make sure everything is OK, and fit in a three week deal away from the car with SWMBO prior to LOG.

If I can't readily get replacements, is it possible/acceptable to go with a hard chrome or similar finish and grind/machine to correct dimension? Saw some mention of this procedure in the archives, but don't know if it's OK, where to look for a specialist that can do the work, and a bit about how it might be done. Is this the same or similar to a procedure that would be used by engine machine shops on crankshafts or whatever? I would get the spider run-out checked at the same time.

As an alternative, anyone got some extra usable shafts?

[fatboyoz]

Stu,
I got mine from Tony Thompson Racing in the UK.
http://www.tonythompsonracing.co.uk/pricelist.pdf
Page 6, item TTRFD 016.
For good measure, also fitted TTRFD 008.
Regards,
Colin.

Got the verdict back from my mechanic late this afternoon. At least one of my outboard drive shafts is worn out where the outboard bearing locates. The bearing failed in quite spectacular fashion and is now shaft has too small an OD to locate the bearing correctly. The other shaft shows some wear as well, and he figures it should also be replaced. Haven't looked at them yet, but Malcolm is pretty sharp on this stuff so pretty confident they are past the Locktite solution. He prefers I source replacements if possible.

I talked with Dave Bean and he has none in stock, so about a month to get new ones made up. Have inquiries at all the usual suspects and waiting to hear back. Can anyone (either side of either pond ) suggest an immediate source? Really want to get the car back together for LOG32 in Orlando end of October. Time is getting short to get the car back to right, drive around a bit to make sure everything is OK, and fit in a three week deal away from the car with SWMBO prior to LOG.

If I can't readily get replacements, is it possible/acceptable to go with a hard chrome or similar finish and grind/machine to correct dimension? Saw some mention of this procedure in the archives, but don't know if it's OK, where to look for a specialist that can do the work, and a bit about how it might be done. Is this the same or similar to a procedure that would be used by engine machine shops on crankshafts or whatever? I would get the spider run-out checked at the same time.

As an alternative, anyone got some extra usable shafts?

[Higs]

Stu

I have recently got a pair from SJ Sportscars here in the UK. Only waited 1 week. The other suppliers seemed to show them in their catalogues but I did not enquire. They were about ?150 + VAT each.

Metal spraying is possible but as you say finding someone to do it is not easy. Building the surface up through plating is also an option but I do not know much about this. You might end up paying enough on this route for you to justify buying new. I tried to grind down the outer bearing surface, shrunk fit a sleave on and the re-ground the bearing surface and the taper. I worked ok but I decided that reducing the diameter of the shaft at the outboard end (where the bending moment is greatest) is not not ideal (the cross-sectional area was reduced by greater that 10%). If it breaks there, the first thing you will know is that the wheel is overtaking you (done that at 30mph in a straight line to know that faster on a corner would not be fun).

Hope this helps.

Richard

[UAB807F]

Hi Stu,

I've got to say that my first option would be to replace with new ones from a known supplier simply because it should return everything to "as new" and hopefully I won't have to fix that one again.

Having said that, metal spraying to build up a shaft is a known and well-used practice in industry. My memory is hazy but I seem to recall the procedure was to clean up the shaft in a lathe, metal spray to above requirements and then grind back for a bearing surface. We sub-contracted our work but would be having a regular weekly shipment to the contractors for repair. It was a relatively cheap process, well, cheap compared to new pump shafts at the time.

The only problems I ever saw were due to corrosion where the sprayed surface came into contact with the fluid duty in chemical pump applications. The sprayed surface might well be corrosion proof itself but it is porous to some extent and under constant immersion you'd get corrosion of the substrate. However I'd say that's not a problem with the Elan application and personally I'd be ok in using sprayed shafts.

The downside is that technically you've got a thinner load bearing section by whatever depth they need to machine off. Normally this is only a few thou' to remove bearing damage and not a major problem, although of course if you're already on design limits with more power transmission, YMMV. The metal spray restores the dimensions but I would never consider it to restore the full mechanical properties of the original metal in terms of power transmission. So in the case of a race car for example, I'd hesitate.

Brian

[elancoupe]

Stu,
The steel (keyed) TTR shafts are the way to go. Generally, when I order from TTR, the parts are in my hands in 2 days (USA).

Shpuld you need used units, I have a pair here that would work - let me know if it comes to that.

[RotoFlexible]

RD Enterprises stocks steel shafts (probably Tony Thompson units) at $500/ea. I bought mine from Ray, along with steel hubs. No more worries in that area. Depending on shipping and currency exchange, it may be less expensive to order direct from TTR.

[steve.thomas]

I got one recently from Miles Wilkins at Fibreglass Services for about 150 GBP (fitted !).
Steve.

[garyeanderson]

176 GBP each from Tony Thompson as of February of this year.

Gary

[stugilmour]

Thanks very much guys. Very helpful.

Ray at RD wins the 'contact back lottery' and is shipping them today UPS. He confirmed they are the TTR billet steel units with stock configuration keyed shaft and enlarged threads and nuts (9/16" up from stock 5/8"). I was so freaked I didn't notice he has them featured in the Plus 2 parts list. A bit spendy at $950 for the pair but should get things back to right next week. I think Bean was about $540 each, but apparently they are their own design and manufacture. If I wasn't in such a rush as pointed out the TTR deal is considerably cheaper on their web site, but I didn't phone to check stock & price with Ray on the case.

Good news that I found this issue out before setting off on the long trip.

[mr.vman]

Stu, Good news on the shafts. Before you install, check that the brake rotor mounts solid on the ears of the new shaft. I had to grind some of the rotor to fit the fingers of the new HD shafts. Check the bolt fit also before install. Hope this helps. Steve V. In Arizona

[stugilmour]

Thanks Steve. I am also going to check if I have to relieve the spider holes for the Ray supplied CV shafts. I had a heck of a time getting the hub carrier assembly off of one side as binding on the brake rotor holes and spider holes. Understand this is a pretty common problem with the stock outboard shafts, sounds like same issue with the TTR ones as well.

UPS says Tuesday for the parts, which is pretty good.

[kstrutt11]

I had one of mine metal sprayed and ground back, this was around 10 years ago and cost around GBP50, never had a problem since.

[Jason1]

http://www.youtube.com/watch?v=oGPeyjRh ... re=related

I have never seen this process; have a look at the Youtube clip. Interesting stuff.

[mr.vman]

Stu, Do not press on the lugs/ears/fingers, of the out board stub axles, they will bend. Press on the center, use a small socket or? Avoid the lugs, if they bend there will brake rotor "run out". Shops will put the stub axle on the bed of the shop press and press bearings in, do not allow. After the stub axles are installed, check brake rotor, "run out". I can live with .004" before (less is better)installing on the car, brake pedal pulsations can be felt. While set up for brake rotor "run out". Perhaps install the outer Knock off hub adapter and check "run out" on the face where the pins are located. Use AN bolts, no threads in bearing. Are you using the RD CV half shafts also? If you are, the half shafts have the inner "stub axle" installed. You will have to remove your old stub axle from your differential. The worse part is, getting the inner snap ring on the stub axle bearing, another post. By the way, the CV joints are VW type one. You will need a triple square tool to service. Just my opinions only, hope this helps. Steve V, in Arizona

[garyeanderson]

Stu, Do not press on the lugs/ears/fingers, of the out board stub axles, they will bend. Press on the center, use a small socket or? Avoid the lugs, if they bend there will brake rotor "run out". Shops will put the stub axle on the bed of the shop press and press bearings in, do not allow. After the stub axles are installed, check brake rotor, "run out". I can live with .004" before (less is better)installing on the car, brake pedal pulsations can be felt. While set up for brake rotor "run out". Perhaps install the outer Knock off hub adapter and check "run out" on the face where the pins are located. Use AN bolts, no threads in bearing. Are you using the RD CV half shafts also? If you are, the half shafts have the inner "stub axle" installed. You will have to remove your old stub axle from your differential. The worse part is, getting the inner snap ring on the stub axle bearing, another post. By the way, the CV joints are VW type one. You will need a triple square tool to service. Just my opinions only, hope this helps. Steve V, in Arizona

This is how I do them,
Sows Ear Chassis - page 7
elan-f14/sows-ear-chassis-t24752-99.html

Gary