Tomorrow I plan on replacing the rubber brake hoses on my 1979 W116 300SD. The previous owner told me $2,000 was spent replacing the complete brake system but the hoses appear to be original 1979 (I will have to look at the tags on them). The brake fluid is dark and the pedal seems a bit mushy, especially when it comes to fast stops. The two rubber caps that go on top of the reservoir were missing and I found a mismatched set at a wrecking yard, but I should probably buy a new pair.

I bought a set of four new German FEBI brand hoses. Are the hoses supposed to use sealing washers (none were provided)? Would it be a good idea to use teflon thread tape on the new brake hose threads (I had thought of using anti-seize thread lubricant)?

I plan on releasing all four bleeder screws then using the remaining Valvoline SynPower DOT4 brake fluid that I have had in the garage for a while to flush any debris out. Then I plan on replacing one hose at a time and topping up with fresh Valvoline SynPower brake fluid. I will then have my roommate pump the brakes while I bleed the calipers, starting from the right rear and moving to the left front. Hopefully it goes well.

My next task will be to drain the transmission and torque converter, then to install the new transmission cooler hoses and sealing washers and filter with pan gasket. I will probably fill it with synthetic ATF as I try to stick with synthetic fluids. If the filter an inside of the transmission looks clean then I probably won't have to change the new ATF for a while--but if it looks really dirty then I will probably need to change the new ATF in short time, especially since the synthetic oil will probably clean the transmission and clog the new filter or lift and push the contaminants through the transmission.

After this I need to drain and refill the differential and start thinking about covering the boots to protect them from the weather and containing the grease if they give out.

I think the PO lied to you.

__________________
Regards

Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.

Maybe. All the calipers, pads, rotors, master cylinder and booster look like they have been replaced recently. Strange that old hoses would be left.

If car was run previously using standard brake fluid, I'd avoid using synthetic. Seals and master cylinders can be rendered inop with synthetics, happened to me with a late model car, FWIW.

No teflon tape, no anti-seize! The threads only hold the sealing surfaces together, not perform the sealing themselves. You just need the hoses.

Make sure you have some flare nut wrenches to undo the lines... its quite easy to damage the nut on the solid line. A squirt of your favorite penetrating lubricant a few hours before you start working is a good idea here too.

Synthetic ATF seems to be ok, according to everyone else here... I like the fancy Febi fluid, no idea what it really is.

Covering differential boots? Don't do anything unless they're already damaged, they they should be replaced. Those axles spin quite fast back there. You don't want to do anything that will throw off balance or come loose.

Good luck,
Jaime

If the flare nut wrenches don't work for whatever reason, go with a good set of vise-grips.

All four hoses were original! They had 11/78 ATE tags on them and looked badly--with tears, cuts, and cracking.

I used flare nut wrenches and nothing on the threads. All went fine and I was making good time until I got to the right rear hose and the fitting rounded off. I ended up having to use vice grips to remove the old hose. I used a small pipe cutter and cut the flare off of the hard line and removed the fitting. Now I need to find a new one and then reflare the hard line.

It might be easier to just replace the whole section of hard line. Reflaring the metal line is a little tricky and if its old might not be worth the effort. They are readily available and not expensive.

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

The brake job is done! What a difference; the pedal is very firm now.

I got a hose fitting from a 300D at Pull-A-Part, then removed the section of hard line going to the right rear hose and took it to Williams Oil Filter Service Company where I had a bubble flare added to the cut end (for a cost of $2.73). The length was not noticeably affected since when I cut the end it was right behind the flare.

The inside of the master cylinder reservoir was dirty so I popped it off of the master cylinder. Then I plugged the two bottom holes with gloved fingers, added fresh brake fluid, installed the cap, and shook it several times so the fluid would slosh around and clean it. After doing this a few times the inside of the reservoir looked very clean and I then reinstalled it.

I put in Brake Best DOT4 475F heavy duty brake fluid. I feel much better that now the entire brake system is either brand new or recently serviced. When I saw how bad the hoses looked when I was under the car one day, it became a source of worry.

The weather was too cold and wet to do the job any sooner (but it did rain today), and I actually did order the hoses a while back but they were stolen off my porch when UPS delivered them and someone found the empty box in the park. At least UPS refunded the cost and paid for new hoses.

I am so happy to have this worry out of my way. Now on to the transmission (if it doesn't rain too hard next weekend).

Yesterday I replaced the transmission filter, pan gasket, drain plug sealing washers, torque converter drain plug sealing washer, and cooler line hoses. The new Continental hoses have springs on them to keep them from kinking.

So far I haven't noticed any leaks. I drained the torque converter and allowed the pan to air dry after cleaning it to avoid getting lint in it. The inside of the transmission looked like new and the fluid that came out looked very clean.

I put in about 6 quarts of Red Line Synthetic High-Temp ATF (Dextron III/Mercon compatible). It is filled to 30mm below the minimum mark when running cold and right on the maximum mark after the car has been driven a long distance.

The transmission seems to shift smoother now and I don't have to worry about when the last time the filter/fluid was changed. I guess it was worth the 7 1/2 hours it took to do the job correctly!

I also got some Red Line 80W140 hypoid gear oil for the differential. I think I will clean the breather valve on the differential while I'm at it, since they can clog and the built up pressure can blow seals.