Thread: Adaptor shaft

My last suggestion would save you cutting off the thread on your MSA output shaft and trying to tap it.

The drive flange emulates the zf set up.

Apart from making the flange the rest is off the shelf parts, proven, plentiful and real cheap.

Have you looked at the image I posted?

http://www.aulro.com/afvb/attachment...t-imgp3239.jpg

I'll see if I can find some info on the Q4 that you mention, out of curiosity. Otherwise I'd run with the alloys suggested by Ancient.

Yes I have seen that image and while The idea has merrit, you are still using the propshaft flange instead of mating directly to the spline on the Isuzu mainshaft. Propshaft flanges are designed to interface with a propshaft where the uni-joints will take up any misalignment. In fact a propshaft requires longitudinal misalignment between the ends to prevent brinnelling of the uni-joints.

Every time there is a joint you introduce potential misalignment and vibration. In the design above there is the Isuzu propshaft flange that interfaces on the mainshaft, fit of the 4 bolts between the flange and adapter, the adapter that interfaces with the flange and then the spud shaft and its interface with the LT230. That is 5 separate interfaces (if you don't count the 4 bolts separately). Why not have an adapter shaft that interfaces directly on the Isuzu mainshaft (like the ZF adapter shaft) and then into the LT230. This reduces the potential for misalignment to two interfaces.

As I questioned earlier. Do we know if the propshaft flanges are true?

i.e.:

1. Are the bolt holes equidistant and aligned with their opposite hole across the mainshaft centre?
2. Is the flange parrallel (90 degrees to the mainshaft in all planes)
3. Is the flange balanced?

The only reference I can find to 'Q' is that it could mean quenched steel or hardened, like 'W' for weathered steel.

The 4 could be the type of quenching method or just the grade like bolts, grade 4 is medium carbon, cold drawn steel.

These days you specify the alloy along with the desired treatment method.

SAE steel grades - Wikipedia, the free encyclopedia

OK Lotza. I've just finished talking to Marks Adaptors.

You'll feel somewhat vindicated regarding your previous suggestion of gearbox mainshaft direct to t/c input gear.

For general purposes Marks use simple straight splined spud shafts to connect the gearbox output shaft to the input gear. Held on by draw bolt.

For significant power output situations they connect the input gear directly to the gearbox output shaft. This will generally require reworking existing shaft or completely new shaft. Thousands of $$$

Marks don't cut their own gear. They have a parent company that does the work. Send Marks an email with specifications and they will forward to the parent company. The parent company will more than likely also require samples of the parts to be joined by the adaptor. The parent company will then get back with a quote. Price falls considerably for 15 or more units.

You should send your email to Nick at Marks as he now has some idea through my discussion with him.

So what your saying is they do what dougal did, or for higher horsepower they do what sitec did.

I have my reservations about trying to preload the MSA output bearing by using the zf style 10-12mm draw bolt system.

I've not been able to buy or download a workshop manual for the MSA box (and it may be a chapter in a more comprehensive NPR manual). However, what I have found is the workshop manual for the MSB gearbox.

If anyway similar to the MSA, the MSB requires the drive flange nut to be torqued to 226 Nm, or roughly two thirds the force required to do up the 200Tdi damper bolt - not insignificant.

Others with better knowledge might like to comment on whether the zf style draw bolt can cope.

You might consider Dougals set up, much like what you are proposing, but he preserves his output shaft thread instead of cutting it off and trying to tap it.

I'm sympathetic to what you are saying about prop shaft issues, that the prop shaft is there to take up any misalignment. But that is a very dynamic system, with suspension movement changing prop shaft angles significantly.

Take away suspension, weld axle casing to chassis, as near perfectly straight alignment as possible to gearbox output, would you need a prop shaft yolk? Sliding splines maybe. Must check out those trucks that use torque tunnels as the chassis to see if they incorporate a yolk.

Sorry Vern, didn't see that slim line comment amongst all my verbal garbage

I'm not familiar with the engineering that Toyota and Nissan use in the area we are dealing with.

Yes, it seems like a Dougal shaft held on by a draw bolt. But do Toyo/Niss output shaft bearings need preload like the MSA, I can't say. If they do need preload then I do not know how they may go about it.

Not like Sitec, as far as I understand Sitecs - still reading.

For high power MSA application I think Marks would say open your gearbox, remove your output shaft, throw it away, remachine a new output shaft that will extend directly into you input gear, using your choice of spline, be SAE10, 28 involute or whatever. Along the lines of one of Lotza's proposals.