Where The Propshaft meets the Tranny...

[pjsmetana]

No, sorry its not the start of a joke :laugh:

It looks like I have a strange issue. Some of you may recall me wondering about the low speed sounds. Anyways, I do have the CV type, but thats not the issue. My CVs are so new that they still have assembly lube on them. When grabbing the Shaft there was 0 play at the CVs... but rather, where it attaches from out of the transmission. What do I do now?

Heres some pics... anything 'look' wrong here? Cuz I really don't know. These are the best pics I could take, with out taking the trans tunnel off.

 

[Andrew Mace]

IF I'm seeing what I think I'm seeing, I'm wondering just what (if anything) is holding the gearbox output flange to the gearbox?

 

[pjsmetana]

IF I'm seeing what I think I'm seeing, I'm wondering just what (if anything) is holding the gearbox output flange to the gearbox?

Yeah, I do feel like something is missing... but what the heck part is it that your talking about? Got any images for me to compare it to? All these pics are from under the car.

 

[Andrew Mace]

Again, hard to say from pictures, but...

First, I'm assuming that the CV joint is at the differential end of the propeller shaft?

Second, it really looks as if the output flange is moving back and forth on the mainshaft, as if the nut ( number 32 in this diagram ) is very loose or missing completely?

 

[bgbassplyr]

I know neat to nothing about Spits, but it appears that the rear transmission mount is missing. The oblong flange with holes at each end that is located just behind the speedo boss should, I think, be bolted to trans mount, which in turn, is attached to the frame. This would be the third mounting point for a three point mounting system, two at the front of the engine and one at the transmission. Without a rear mount, the rear of the trans and the drive shaft will tend to flop around, bang into the frame and tunnel, and generally cause havoc.
As stated above, I am not familiar with Spits, but missing mount is what it looks like to me.

 

[Andrew Mace]

I wondered about that as well, Jim, but wasn't sure. I think you've confirmed it!

Pete, was this car originally an OD gearbox-equipped car? The gearbox mount on OD cars is very different from that of the non-OD cars. But that's possibly a moot point, as there might be no mount at all!?

 

[pjsmetana]

Again, hard to say from pictures, but...

First, I'm assuming that the CV joint is at the differential end of the propeller shaft?

Its the same at both the Diff and the Overdrive.

Second, it really looks as if the output flange is moving back and forth on the mainshaft, as if the nut ( number 32 in this diagram ) is very loose or missing completely?

It is most definitely loose where it goes into the OD, but I don't see that being the right part, as, again, I have overdrive. Is there a similar item like this on the OD? As it is loose enough to be a probable explanation.

possibly #33 on this? https://www.spitbits.com/1500/1500overdrive74-80.htm

 

[TR3driver]

possibly #33 on this? https://www.spitbits.com/1500/1500overdrive74-80.htm

Yup, that's it. Unless of course the OD internals have gone away somehow.

I believe your next step is to undo the driveshaft, and check on that nut. You might be able to get in there by just undoing the 4 bolts that hold the flanges together, but I wouldn't be surprised if the whole driveshaft has to come out to get enough room to work. The big nut gets torqued to some unreasonably high value, like 100 ftlb.

 

[pjsmetana]

possibly #33 on this? https://www.spitbits.com/1500/1500overdrive74-80.htm

Yup, that's it. Unless of course the OD internals have gone away somehow.

I believe your next step is to undo the driveshaft, and check on that nut. You might be able to get in there by just undoing the 4 bolts that hold the flanges together, but I wouldn't be surprised if the whole driveshaft has to come out to get enough room to work. The big nut gets torqued to some unreasonably high value, like 100 ftlb.

Lucky for me I just bought a new torque wrench today that goes to 120ft/lbs. 3/8 drive too.

How do I hold it still enough to crank it to 100ft/lbs... if its even still there? If it is there, what size is that nut? Also, whats the torque on the 4 bolts/nuts that hold the forward end of the prop-shaft? What about the rear end of the prop-shaft in case I gotta pull that end too?

 

[Don_R]

Andy,

the trans mount is in front of ther right angle drive

 

[Don_R]

Pete,

here is a pic of my CV driveshaft

 

[Andrew Mace]

Again, hard to say from pictures, but...

First, I'm assuming that the CV joint is at the differential end of the propeller shaft?

Its the same at both the Diff and the Overdrive.

OK, terminology in the way here. Apparently the propeller shaft you have has u-joints and not CV joint(s) at both ends. Look at the picture of Don's propeller shaft.

And thanks, Don, for clearing up the mount issue for me! The only Spitfire OD gearbox I've ever had (or seen closeup for any length of time) is in a Mk2 in my barn, but the box sits on a hunk of wood across the main rails. For whatever reason, the previous owner of the car didn't get the mount when he got and installed the rest of the OD gearbox! Somehow it must have worked for awhile, but.... :shocked:

Sadly, that Mk2 itself isn't worth much, but it's got that nice gearbox, a good 1147 engine...and a factory hardtop, all of which I hope to put to good use someday!

 

[Don_R]

Andy,

No problem...I just happen to have a 1980 O/D trans/mounts/shaft to put in my 73.

 

[TR3driver]

How do I hold it still enough to crank it to 100ft/lbs...

What I did was buy a length of flat iron stock at Home Depot, and drill it so it would fit over two of the bolts, leaving enough room for a socket to go on the nut. Similar to this photo (which is actually the side flange for my Stag)

(You may notice some marks where I had to grind away a bit of the bar; due to not getting the holes located just right.)

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]... to 100ft/lbs ...[/QUOTE]Please note that I didn't mean exactly that value, just that it's somewhere in that range. You (or someone) needs to check a shop manual.
<div class="ubbcode-block"><div class="ubbcode-header">Quote:] what size is that nut?[/QUOTE]Sorry, all I remember offhand is that it is larger than 1".

<div class="ubbcode-block"><div class="ubbcode-header">Quote:] Also, whats the torque on the 4 bolts/nuts that hold the forward end of the prop-shaft? What about the rear end of the prop-shaft in case I gotta pull that end too? [/QUOTE]On my cars, there is no room to get in there with a torque wrench, so I just pull them as tight as I can using a pair of ordinary 9/16" box end wrenches.

 

[pjsmetana]

Anyone have the shop manual for these answers? Nut size and Torque?

 

[Don_R]

Pete,

Here is what I have found

Nut - 1 1/8" (my socket fits)

Torque 80-130 ft/lb (BMHT CD)

driveshaft 26-34 ft/lb

 

[pjsmetana]

Pete,

Here is what I have found

Nut - 1 1/8" (my socket fits)

Torque 80-130 ft/lb (BMHT CD)

driveshaft 26-34 ft/lb

Right on! Thanks man!