-
Relay valve cross reference?
We are in Lake Havasu (AZ) and one of our relay valves is leaking badly (driver side, rear). It seems to leak from the supply port to the exhaust port when I’m not applying the brake. The compressor is keeping up with it (barely) but would like to get it fixed locally before we move on. The Prevost parts book shows the valve part number as 641088 (R12 with horizontal ports). Will that part number cross reference to a standard truck R12 valve that might be available locally? Anybody know of a decent truck service shop in the area?
Appreciate any pointers, Gerald
-
7 Replies
-
A call to Prevost parts will get you the part almost as quickly as you could find it locally. Had you ordered it yesterday it would be on your doorstep today if necessary.
-
Actually any generic valve will work, but the bolt holes might not line up so if in a pinch try to stick with Bendix which is what I think Prevost installed. A lot of truck parts supply houses are likely to carry them.
As far as replacing if you can raise the rear fully AND BLOCK UP THE CHASSIS access is relatively easy by sliding under the coach and then sitting up between the tag and drive axles. I believe the relay valve is mounted to the underside of the floor at that point.
-
The field mx/rebuild kit is Bendix# 102802N. I rebuilt mine yrs ago and all is well still. There are many brass fittings in the R12 that need to be removed from old and indexed just so into the new which ain’t easy.
Here is a link to the BendixQuickReferencwCatalog (see p.33) LINK -
Rebuilding might be the way to go. I have a couple of the kits with me. The issue is finding a safe way/ place to get under the bus. The state parks frown on doing repairs on site. I’ll check around and see if I can find a truck repair place.
-
Obviously the choice is yours, but except for bragging rights rebuilding a $50 part like a relay valve or three port Norgren is hardly worth the effort
-
Jon, completely agree that installing a new/rebuilt valve is the way to go if you are at home or at a Prevost service center.
But we could not find a relay valve anywhere in Lake Havasu. So I was glad to have the rebuild kit with me. It was a simple fix and we did not need to remove the valve nor all the air lines-the time-consuming part. Just removed the snap ring from the bottom of the valve and replaced the supply and exhaust pistons, O-rings and spring. No more leaks! There are two additional O-rings on top that require valve removal but those can wait until I get home.
Interestingly, none of the old O-rings or pistons showed lots of wear or contamination. But the new parts fixed the leak. Maybe the old spring was getting weak.
The cross reference for Prevost R12 #641088 is Bendix 103009X R-12. The repair kit Bendix 102802N will work for all Bendix R-12 and R-14 valves (There are three R-12s and one R-14 in my bus). They are cheap and good to have with you.
Shout-out to Bryan at Lowery’s Truck repair in Lake Havasu who scheduled us in at short notice.
-
Excellent news.
How come nothing ever breaks at home?
Never mind. We don’t drive our coaches at home.
Log in to reply.