Replacement TT Outer Hyatt Sleeve - Modification
Posted: Mon Feb 25, 2019 7:11 pm
The repro 'outer sleeves' for the TT rear axle are pretty good. However they do not come with the grease cup hole or the locating dimple in them.
What do you do?
Well, marking where the grease cup hole should go and drilling it to size is easy enough when you use an old sleeve to locate the hole correctly. You actually need that hole to use the sleeve puller for installing the sleeve (easiest way) and removing it again if needed.
But the locating dimple?
As well as letting you know the sleeve is installed the correct depth and orientation, the dimple is also important to prevent the sleeve rotating around the inside of the housing. Not a lot of strength is needed to prevent rotating, and the dimple works just fine, but if it is not there?
Pressing a dimple in will need a tool made up and some fancy work and high pressure to 'dimple' the hardened steel of the sleeve. This is probably beyond most of us.
Solution1: Could the repro maker put this in before hardening (the repro car sleeves have dimples in)?
Solution2:
a) locate the centre where the dimple should be (using an original sleeve as a template)
b) drill a hole smaller than the locating hole in the housing end.
c) make a 'stepped' plug with the smaller diameter to fit the newly drilled hole in the sleeve, and the larger diameter to fit the hole in the housing.
d) ensure the small end of the plug does not protrude through the sleeve. MOST IMPORTANT to avoid ruining your hard to get TT rear Hyatt! The plug cannot go any further into the sleeve due to the step up to the larger diameter of the housing end of the plug. Don't forget to allow for a bit of wear in the new sleeve when shortening the plug.
e) ensure the larger end is flush with the housing.
f) the new replacement outer cover for the 'felt style' seal will sit down and partly cover the plug in the housing hole, ensuring it will not fall out.
g) if using old style outer seals, a large hose clamp will be needed to cover the plug.
Cheers, Adrian
What do you do?
Well, marking where the grease cup hole should go and drilling it to size is easy enough when you use an old sleeve to locate the hole correctly. You actually need that hole to use the sleeve puller for installing the sleeve (easiest way) and removing it again if needed.
But the locating dimple?
As well as letting you know the sleeve is installed the correct depth and orientation, the dimple is also important to prevent the sleeve rotating around the inside of the housing. Not a lot of strength is needed to prevent rotating, and the dimple works just fine, but if it is not there?
Pressing a dimple in will need a tool made up and some fancy work and high pressure to 'dimple' the hardened steel of the sleeve. This is probably beyond most of us.
Solution1: Could the repro maker put this in before hardening (the repro car sleeves have dimples in)?
Solution2:
a) locate the centre where the dimple should be (using an original sleeve as a template)
b) drill a hole smaller than the locating hole in the housing end.
c) make a 'stepped' plug with the smaller diameter to fit the newly drilled hole in the sleeve, and the larger diameter to fit the hole in the housing.
d) ensure the small end of the plug does not protrude through the sleeve. MOST IMPORTANT to avoid ruining your hard to get TT rear Hyatt! The plug cannot go any further into the sleeve due to the step up to the larger diameter of the housing end of the plug. Don't forget to allow for a bit of wear in the new sleeve when shortening the plug.
e) ensure the larger end is flush with the housing.
f) the new replacement outer cover for the 'felt style' seal will sit down and partly cover the plug in the housing hole, ensuring it will not fall out.
g) if using old style outer seals, a large hose clamp will be needed to cover the plug.