Emergency Hydraulic Parking Brake Switch Broken

[Tange206]

Hello Safari & friends!

So while working on my 91 Sarengti I realized my emergency brake switch was messed up after one of the brake lines going into it explosively detached its self from the switch body, spraying brake fluid all under my center console. Under further inspection, I believe a previous owner installed the inlet brake line wrong and cross-threaded the female switch body with the line causing it to strip the threads when I bumped it. Thankfully I was parked and not moving.

I need help identifying the make and model of the emergency brake switch and any leads on where I can order a new one or a similar one. Please any help would be great, unfortunately, the inlet threads on the original part picture in the attached photos is entirely striped.

[TDJohn]

This is the closest I could find, it is a Ford part, probably made by Borg Warner. Just so you are aware, SMC used many Ford and some GM medium duty truck parts...

https://www.ebay.com/itm/184900355820

This part is physically a bit different, but pretty much has the same function, if you can make it fit/work.

https://www.anythingtruck.com/product/060-065316.html

BTW, in your description, you mention brake fluid. This is not correct, that part is hooked up to the same hydraulic system that runs your power steering and power brakes. Safari used Dextron III, which now the closest would be DEX/MERC oil in the auto parts stores. Considering how old the system is, I would suggest finding a DEX/MERC that is not synthetic oil version. Since you have the older "Oshkosh" chassis version, I'm not sure where the hydraulic reservoir is located on your coach. On mid 90s and later coaches, those reservoirs were located in the service bay area, which is the most rear passenger side compartment. Fortunately for the folks with the later Magnum Chassis coaches, they moved that hydraulic valve and hose assembly outside by the rear axle, and used a long heavy duty park brake cable to activate the valve. This avoids having the oil spill mess under the dash, like you have unfortunately experienced. I hope this will be of help. Let us know how you make out...

[Tange206]

Wow thank you so much! I will check out these links and report back to see if this fixes the issue. Should I bleed the hydraulic lines if I replace the fluid with a new batch of hydraulic fluid? Thanks for the info!

[TDJohn]

Usually it is self bleeding. I know that when I had to add some fluid to the reservoir, after a short while, my brake booster started working funny, especially when it is hot, when running long hot days. It seems that today's ATFs are a bit thinner in viscosity, and I don't think the old system likes the thinner oil. So you may not necessarily flush the system, but that is your call...
I also had a similar thing happen with my leveling jacks. Added some fluid, and shortly after, the rear jacks slowly bleed off now, as in slowly settle when leveling jacks are deployed. Could both be a coincidence? Possibly, but I doubt it. In any case it's a PITA. If you can get your hands on an old stash of Dextron III, per-synthetic days, your odds will probably be better of not having any problems like I experienced.

[Tange206]

Hello again so I'm finally getting around to fixing the hydraulic parking brake for my 91 safari. I got all the new parts from: https://www.ebay.com/itm/184900355820

I had a follow up question about the hydraulic fluid reservoir for the Oshkosh chassis my rig is on. I think I found it in the back engine compartment under the bed pic below. It was bone dry when I opened it which makes sense because I lost a lot of fluid when the switch broke. It does not have any label on it to say what the resivor is for. Any ideas if this is the hydraulic fluid reservoir for the safari??

Thanks!

[eneriksen]

On my Serengeti that reservoir supplies a pump that supplies fluid to the automatic parking, power steering and brake booster. As someone else suggested earlier, use Dextron III non synthetic. Mine was empty also and took over two quarts. All three systems bled themselves fine.

[eneriksen]

Does anyone know where to find a rebuild kit for the master cylinder? A1-Cardone told me today that they no longer do master cylinders.

[TDJohn]

Hello again so I'm finally getting around to fixing the hydraulic parking brake for my 91 safari. I got all the new parts from: https://www.ebay.com/itm/184900355820

I had a follow up question about the hydraulic fluid reservoir for the Oshkosh chassis my rig is on. I think I found it in the back engine compartment under the bed pic below. It was bone dry when I opened it which makes sense because I lost a lot of fluid when the switch broke. It does not have any label on it to say what the resivor is for. Any ideas if this is the hydraulic fluid reservoir for the safari??

Thanks!

I'm not as familiar with the older first generation Safaris, so I'm not sure, though canisters like that are used by other coach makers for hydraulic fluid. You best bet is to see if the supply hose coming from that reservoir, goes to the hydraulic pump on the engine. If it does, then that is the hydraulic reservoir...