Thanks to the generousity of a fellow GMCnetter(who shall remain
anonymous), I have on loan a Ken Thoma Bearing Tool Set. Last night
after dinner, I watched the video and walked right downstairs and pulled
the bearings off both hubs(including pushing out the bearing that was
stuck in the right knuckle) in less than 1 1/2 hours.
This tool set is more than just a "bearing puller". The collet used to
remove the bearings from the hubs is similar in design to Darrell
Winterfeldts, but that's where the similarity ends. It doesn't use a
gear puller, but instead has a solid "bridge" to pull the bearing off.
The removal procedure is to remove the entire knuckle/hub assembly from
the coach and remove the three seal retainer bolts. The rear seal is
removed and the three bolt holes are cleaned and chased from the rear
with a tap. A round "push plate" is placed over the bearings from the
rear side of the knuckle and a three point "bridge" is installed over
the plate using the seal retainer bolt holes. Then the center bolt is
inserted into the bridge and tightened against the push plate. Using an
impact wrench, the bolt is tightened and the hub/bearing assembly is
pushed out of the knuckle.
To remove the bearings from the hub, the outer seal is pushed down as
far as possible and the collet placed around the bearing(the most
tedious part of the process - it takes about 15 minutes of coaxing with
a hammer and tightening the clamp bolts) and drawn up tight. A push
plate is placed over the hub and the two point bridge installed on the
collet. The center bolt is inserted and tightened against the push
plate. Again, an impact wrench is used to push the hub out of the
bearings.
I haven't done the installation yet, but there's no reason it shouldn't
proceed as shown on the video. Installation uses a "T bar" that is
placed under the outside of the hub. The retainer and seal are set in
place and a bearing guide is placed on the "snout" of the hub. The
bearings are placed on the guide and a push ring is placed on top of the
bearings. The center bolt goes through the push ring and threads into
the T bar. An impact wrench is used to pull the bearings down onto the
hub.
The knuckle is then placed on the hub/bearing assembly and a larger push
ring is placed on the knuckle. The center bolt again goes through the
push ring and into the T bar and the impact wrench pulls the knuckle
onto the bearings. Ken also includes a nylon seal seating tool for
installing the inner seal on the knuckle.
I've simplified the process some for the sake of brevity, but it's not
much more complicated than I've described. The video is a very amateur
attempt, but it gets the point across and I admire anyone who will work
in front of a recording video camera and use the tape unedited. Ken
gives several good tips during the video, including how to check the
assembled clearance of the bearings and an easy way to tighten the seal
retaining bolts. The tools are well made(according to Ken, the collet
is heat treated to a hardness of 45-55Rc) and do the job well. An
impact wrench is required, but my cheap B&D wrench and Sears air
compressor worked just fine.
IMO, the tool set is probably worth the $500 asking price and you'd have
a hard time duplicating it for less than that on a one-off basis. As a
disclaimer, I don't know, have never met, corresponded or spoken with
Ken Thoma. I didn't intend to do a review of his tool set, but, with
all the interest on GMCnet concerning these tools, I felt that I should
relate my (limited) experience with this set.
Patrick
- --
Patrick Flowers
Mailto
atri63
The GMC Motorhome Page
http://www.gmcmotorhome.com
anonymous), I have on loan a Ken Thoma Bearing Tool Set. Last night
after dinner, I watched the video and walked right downstairs and pulled
the bearings off both hubs(including pushing out the bearing that was
stuck in the right knuckle) in less than 1 1/2 hours.
This tool set is more than just a "bearing puller". The collet used to
remove the bearings from the hubs is similar in design to Darrell
Winterfeldts, but that's where the similarity ends. It doesn't use a
gear puller, but instead has a solid "bridge" to pull the bearing off.
The removal procedure is to remove the entire knuckle/hub assembly from
the coach and remove the three seal retainer bolts. The rear seal is
removed and the three bolt holes are cleaned and chased from the rear
with a tap. A round "push plate" is placed over the bearings from the
rear side of the knuckle and a three point "bridge" is installed over
the plate using the seal retainer bolt holes. Then the center bolt is
inserted into the bridge and tightened against the push plate. Using an
impact wrench, the bolt is tightened and the hub/bearing assembly is
pushed out of the knuckle.
To remove the bearings from the hub, the outer seal is pushed down as
far as possible and the collet placed around the bearing(the most
tedious part of the process - it takes about 15 minutes of coaxing with
a hammer and tightening the clamp bolts) and drawn up tight. A push
plate is placed over the hub and the two point bridge installed on the
collet. The center bolt is inserted and tightened against the push
plate. Again, an impact wrench is used to push the hub out of the
bearings.
I haven't done the installation yet, but there's no reason it shouldn't
proceed as shown on the video. Installation uses a "T bar" that is
placed under the outside of the hub. The retainer and seal are set in
place and a bearing guide is placed on the "snout" of the hub. The
bearings are placed on the guide and a push ring is placed on top of the
bearings. The center bolt goes through the push ring and threads into
the T bar. An impact wrench is used to pull the bearings down onto the
hub.
The knuckle is then placed on the hub/bearing assembly and a larger push
ring is placed on the knuckle. The center bolt again goes through the
push ring and into the T bar and the impact wrench pulls the knuckle
onto the bearings. Ken also includes a nylon seal seating tool for
installing the inner seal on the knuckle.
I've simplified the process some for the sake of brevity, but it's not
much more complicated than I've described. The video is a very amateur
attempt, but it gets the point across and I admire anyone who will work
in front of a recording video camera and use the tape unedited. Ken
gives several good tips during the video, including how to check the
assembled clearance of the bearings and an easy way to tighten the seal
retaining bolts. The tools are well made(according to Ken, the collet
is heat treated to a hardness of 45-55Rc) and do the job well. An
impact wrench is required, but my cheap B&D wrench and Sears air
compressor worked just fine.
IMO, the tool set is probably worth the $500 asking price and you'd have
a hard time duplicating it for less than that on a one-off basis. As a
disclaimer, I don't know, have never met, corresponded or spoken with
Ken Thoma. I didn't intend to do a review of his tool set, but, with
all the interest on GMCnet concerning these tools, I felt that I should
relate my (limited) experience with this set.
Patrick
- --
Patrick Flowers
Mailto
atri63The GMC Motorhome Page
http://www.gmcmotorhome.com
