need help! BrakeMasterCylinder ?

[coolerow]

I need help finding a Brake Master Cylinder for my '76 Argosy 28 footer. I tried parts stores and they hve no clue what im talking about, cant find it. Can anyone tell me what the current part# is or any other information i can use to find it? Like what chassis is used? Oh, and one more question...when changing master cylinder, what else should i change? And if i can get information on those parts too please. Basically my brakes are failing badly, to the point where its not safe to move around, and i noticed a rear drum cylinder leaking.

If I can get any information for any of these parts I will greatly appreciate it, THANKS!!!!!

coolerow@verizon.net

[thenewkid64]

Try a NAPA if you have one local. Most of the big retail chain stores I have been to, the kid behind the counter is younger than my coach. When I say I need a part for a 78 Argosy Motorhome I get a blank stare and a I can't find that in my computer.

If you try the retail stores tell them it is a chevy P-30 van chassis with a 454. That will get you close. A few members have changed out their master cylinder, so I would think they are out there.

The rears are a whole 'nother ball of wax. You have to remove the axle half to get to the shoes/wheel cylinder. The axle is attached to the drum and is removed as a unit. This may be beyond the skills of many of us. I know of one member that DIY'ed them and was happy with the savings/results.

[coolerow]

great, thanks a lot. very much appreciated.

[74Argosy24MH]

As long as you have to bleed it anyway replace the 2 rubber lines to the front calipers and the one to the rear axle. Check your steel lines carefully for rust.

Replace both wheel cylinders when you do the back. 8 bolts hold the jack shaft in, 2 large nuts and a lock ring hold the hub on. Stuff a rag in the end of the axle tube when you get the jack shaft out, anything that gets in will end up in the carrier.

The large nuts need to be torqued because they set the bearing preload and have to be locked or you will loose the hub. Replace the hardware, the springs are bound to be rusty and lost a lot of temper. Replace the jack shaft gaskets. Other than that it is about the same as drums on a car just twice as large.

John

[PeterH-350LE]

Originally posted by 74Argosy24MH
..... Other than that it is about the same as drums on a car just twice as large.
......

It's a biiggg pain.
You need breaker bars, heavy jacks, a torque wrench and you will get dirty.
Your leak may turn out to be the oil seal, rather then the wheel cylinder.
The wheel cylinders are almost impossible to bleed without a special (home made) wrench.
The drums should be inspected and turned if needed and new wheel bearings should be installed.
Like John said, if new wheel bearings are installed and you don't torque the axle nuts, they will seat later and you will loose all your gear oil, if not the wheel itself.
Its best to find a trusted big rig garage...
you can pm me if you decide to tackle it.