Bill (and list), here are some snippets from messages from 2002 and
2003. Short answer is that Peter Vucinic, owner of the works TR-4 was
going to make a few improved shafts in Aug of 2003. Cambridge also sells
an uprated shaft but at least one owner was unimpressed.
From uncle jack in 2002:
There have been a couple of TR engines blown because of failure of the oil
pump drive shaft -- the one that fits in the gear and drives the distrib
and oil pump.
If there is a heavy duty one on the market somewhere, please let me know.
Reply from Dean Tetterton:
I know that Cambridge Motor Sports in the UK list an up rated shaft for
39.50 pounds. Don't know of anyone that has tried it. That is about
$63.20 without shipping.
I have seen a lot of the one's taken from engines that are bent, so
Used one's aren't always useable. Sounds like it could be a needed
Project.
Dean Tetterton
Reply from Glen Effinger:
FWIW just about every used distributor shaft I find is bent. I polish the
male tang a bit & take off sharp edges & also edge-break & clean-up the
female slot in oil pump shaft. Also don't hammer the engine hard until the
oil gets to temp. I too am interested in upgrades??? Glen.
From Joe (B):
I have an uprated oil pump shaft from them {Tony adds: Cambridge} (the
short one that goes
into the rotor). It only has splines to press it into the rotor and
the machining of the slot at the top still has sharp edges - no
radius. I was a little disappointed to see that. So far, I am only
keeping it as a spare. Joe(B)
From Peter Vucinic in Aug 2003:
Many thanks to all those that contributed to my TR4 Oil pump shaft problem.
Much good information and ideas were bandied about. So, to this end I have
decided on having my own pump shafts manufactured as follows: -
1. Staring with 1/2" linear bearing shaft material. Readily available 'off the
shelf', hardened, ground precision rod. Case hardened to a depth of about
1-to-1.5 mm. The material is difficult to machine. But it can be done.
2. Have the distributor shaft drive tang slot machined with a radius in the
bottom. This should be able to be accomplished using a ball nose milling
cutter.
3. Use Greg Solow's idea of drilling and taping the pump shaft and pump
rotor.
4. I am also looking at having the oil pimp body machined to take a bronze
bush, at the rotor end.
I have ordered the material(s) and I should have the finished product in a
week or so. I will advise of the end result for those of you that are
interested.
Kind Regards
Peter Vucinic
WORKS-4
TR-4
From Kas:
That shaft material sounds very much like what we call "drill rod". Cheap
and available at most steel servers. Available in many diameters,.
Reply from Peter:
Kas,
The material I am using is definitely not along the same lines as drill rod.
Linear rod is a precision ground, hardened bar used in such applications as
material handling/packaging equipment, where linear motion ball bearing
units are required.
I am getting the specification sheet for this material, but haven't seen it
as yet. Typical mechanical properties for this material will be similar to
the below: -
Hardened & ground - inch dimensions. Steel: Ck60 Surface hardness: 62
Tensile strength: 550-750 N/mm
Kind Regards
Peter Vucinic
WORKS-4
TR-4
At 10:20 PM 7/4/2004, Bill Babcock wrote:
>Seems like I remember a thread about better pump shafts. This part is
>obviously flawed. The stress in those sharp corners must be huge. Likewise
>the drive slot. Does anyone make an improved part with radiused edges?
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