There are some other wiring changes that have to be made to the power master
unit to make it work reliably with the GMC coach, as well as replacement of
the relay. The original relay was one of the weak points with the design. I
am sending a copy of the drawings etc to Thom Hole who was nice enough to
get me a remanufactured unit in North Carolina. I will scan the drawings
and engineering data and see if it can be put on Patricks server for every
one to use.
I received the information from Al Hamilton another member of the GMC
Heritage Cruisers. He was most gracious and copied for me, all of the data
that he obtained in Candada.
>-- [ From: Eugene Fisher * EMC.Ver #2.5.3 ] --
>
>I know nothing about these units but the following seems to indicate
>some changes have to be made
>
>----
>There are other modifications that you will have to make to the
>powermaster unit to get it to work reliably on the coach, such as
>replacing the relay.
>
>----
> I was on the level east of Denver my parking brake light came on,
>telling me that I had a problem with the Power Master brake system. I
>soon found a place where I could pull off the road and check it out. If
>this had happened coming down that mountain I would probably have cut
>an eight foot wide swath half way through Denver before getting her
>stopped. I found the relay that turns the pump on was defective. I
>figured out a way to turn the pump on to charge the accumulator that
>would give me 4 or 5 stops before the light would again come on. By
>using the tranny to slow down and keeping a good distance from the
>vehicle in front of me I was able to go on. I stopped at the first rest
>area in Kansas to recharge the accumulator and found some more free
>coffee, this was really free.
> I figured that I would be better off to get to KC in the wee hours
>of the morning when the traffic would be light. After stopping several
>times to nap and charge the accumulator I got to my brother Gerald's
>place at 4:00 AM. The light came on after I turned the last corner and I
> had no power assist to stop at his house. I shut down and went to sleep
>. Got up and went to work cutting the old relay off the motor and wired
>a Radio Shack relay to it and got my power brakes back again.
>Dallas
>-----------
>
>Sounds like the relay is critical ??
>gene
>
>
unit to make it work reliably with the GMC coach, as well as replacement of
the relay. The original relay was one of the weak points with the design. I
am sending a copy of the drawings etc to Thom Hole who was nice enough to
get me a remanufactured unit in North Carolina. I will scan the drawings
and engineering data and see if it can be put on Patricks server for every
one to use.
I received the information from Al Hamilton another member of the GMC
Heritage Cruisers. He was most gracious and copied for me, all of the data
that he obtained in Candada.
>-- [ From: Eugene Fisher * EMC.Ver #2.5.3 ] --
>
>I know nothing about these units but the following seems to indicate
>some changes have to be made
>
>----
>There are other modifications that you will have to make to the
>powermaster unit to get it to work reliably on the coach, such as
>replacing the relay.
>
>----
> I was on the level east of Denver my parking brake light came on,
>telling me that I had a problem with the Power Master brake system. I
>soon found a place where I could pull off the road and check it out. If
>this had happened coming down that mountain I would probably have cut
>an eight foot wide swath half way through Denver before getting her
>stopped. I found the relay that turns the pump on was defective. I
>figured out a way to turn the pump on to charge the accumulator that
>would give me 4 or 5 stops before the light would again come on. By
>using the tranny to slow down and keeping a good distance from the
>vehicle in front of me I was able to go on. I stopped at the first rest
>area in Kansas to recharge the accumulator and found some more free
>coffee, this was really free.
> I figured that I would be better off to get to KC in the wee hours
>of the morning when the traffic would be light. After stopping several
>times to nap and charge the accumulator I got to my brother Gerald's
>place at 4:00 AM. The light came on after I turned the last corner and I
> had no power assist to stop at his house. I shut down and went to sleep
>. Got up and went to work cutting the old relay off the motor and wired
>a Radio Shack relay to it and got my power brakes back again.
>Dallas
>-----------
>
>Sounds like the relay is critical ??
>gene
>
>
