Travco 270 lost the Hydrovac brake booster

[Acesneights]

I pulled up to a light and smoke started pouring out the exuast. I thought I dropped a piston. It was smoking white so bad I could not see the camper. It smelled like oil. I was about to whip out the Triple A gold when i started clearing up. The motor was running smooth. So We continued on and I noticed the brake pedal got real hard and the brake light came on. I check the fluid and it was full in the master. We got the the Military truck Rally in NH and I bled all four wheels and had good fluid. When I pressed the brake pedal with it running it ran like crap so I clamped off the vacuum lines to each vac one at a time and determined the back one is blown. I guess it must have sucked in some brake fluid . The smoke was only coming from the left bank but the vac tee for the booster is in the runner that goes to the rear r/s intake port so that could make sense.\nI plugged the vacuum line on that booster and drove 100 miles home(not recommended as it makes the RV much harder to stop.I grew up driving old beat up overloaded Mack Dump trucks).No smoke at all. I have been trying to find a replacement. So far this is what I have come up with. When I confirm I will post in part numbers section.\nhttp://www.bendixcatalog.com/PartDetail.aspx?P ... er\n\nAlso NAPA NBB519241 looks like it could be correct. That is the listing for a 220 but I am 99% sure the dual circuit Vac boosters on the 74/75 220's were the same as the 270. I actually swapped this one that went bad from a junk 74 220 so I know it's the same.\nEdit:That NAPA # is incorrect and I believe is for earlier single circuit systems however the 1974 Travco 220 I have sitting here has the same boosters as my 1975 Travco 270. I actually swapped one.

[Acesneights]

Perhaps ??\nhttp://www.rockauto.com/dbphp/x,catalog,1,part ... 18016.html

[Acesneights]

Ok The NAPA part # I "Believe" is for the older 220's with single circuit drum brakes.\nI am fairly certain the cardone number 518016 is correct. The NAPA version of that would be NBB 518016\nt looks almost identical save for the rear hanging bracket. I may have to fab a little. The dimensions are all correct as far as brake line size and overall size. I got one from Rockauto ordered for 146$+ core\nAlso I believe most 270's have 15x4 inch brakes. The Brake shoe hardware kit is Raybestos H9223 if you have the 4 springs.\nWhen I get the parts in a few days I will confirm they are correct.

[Acesneights]

Also lost a rear wheel seal. They were new so I must have pinched it. NAPA 33136

[77Travco]

Dang that sucks... i dont envy you having to pull the rear drum to change that wheel seal.\nYou reminded me of the day that i bought my Travco... i drove it 80 miles home with front brakes only. I agree... definitely not recommeded but i just went real slow and easy.\nGood to have those part numbers posted!

[Acesneights]

Well, got the new booster. It looks right except the mounting bracket is off a little but at this point I may be better off to redo the mount on the Travco to match it. It's close.

[Acesneights]

Ok so did the job yesterday. The booster was correct except the rear mounting bracket. I was gonna fab an adapter bracket but the rear cover on the boosters are interchangeable and it was easier just to swap the rear cover. Make sure you mark where it was on the old one to a point you can line up on the new one. I cleaned mine up and painted it as well. It went in will little issue. The only problem was trying to get the steel vacuum line back in. I could not get it lined up and the threads started due to my Travco having Dual exhaust and the muffler being in the way. I cut the tube, threaded the end ino the booster then reconnected with some rubber hose.. The Travco has a full solid pedal which it never had since I changed everything last year. I had harvested this booster from a junker I have but I suspect it was never any good.\nI also had a bad wheel seal. I don't think I drove the seal in far enough when Installed it originally as it was riding on the rusty part of the spindle and the wear shows it was not riding true.\nI opended up the booster and it was flooded with rusty brake fluid. That was most likely my smoke.

[Acesneights]

The bad wheel seal.

[77Travco]

Nice work swapping the back on the booster. Good thing you noticed that wheel seal early. I am not even sure if those brake shoes are available anymore... is there a part number for them around here somewhere? I really should go and buy a few sets just to have.\nIt sure is nice to be able to do the work yourself... I can only imagine what a shop would charge to do that job.

[Acesneights]

Yes they are available from a few sources. NAPA can still get them although you bets look them up yourself as most of the couter guys are lazy. Alretta Truck parts in Mass can get them and most brake shops can re line them.\nMine are 15x4 which was common on the Travco M500