I am just about to bleed and flush the brakes on my 85 300D.

I put in new discs/pads all round plus rebuilt front calipers and new front flex hoses.

I have a pressure bleeder. For a flush, I would normally start with rear passenger then rear driver, then front pass then front driver.

But with new calipers and flex hoses on front, do you think it would be best to bleed/flush fronts first?

Or perhaps bleed front to get air out, then flush in normal way?

Not a big deal, but you guys often have good ideas!

Just on my way to pick up some DOT4. I think I will get 4L seeing it might be hard to get all the air out.

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

I'd just start in back as usual, at the furthest point from the master cylinder, so the right rear caliper as you stated. Go around twice.

Even with all four calipers totally drained, all four new soft lines, and three new hard lines due to rounded off nuts, I didn't even go through 2 liters and I went around three times. And that was to get all the little bits of junk out that was in the remaining corroded hard lines, the air was out before I was done with the first liter.

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1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

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Are you supposed to bench bleed the new calipers first?
Just curious, I read that somewhere, may have been the FSM, though I don't know how to do it.

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1983 W123 300TD US spec Turbo engine, with Euro bumpers and manual climate control, and manual transmission.

I asked about that in another thread, and one member said it was a waste of time! I am used to filling hydraulic parts, like the chain tensioner on my R107, before installation.

However, the feed to the caliper is low down and the bleed screw at the top, so air should be displaced as the caliper cylinder fills.

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

The next part of my brake saga.

I let the new front calipers fill first until no more air came out. Then I started a normal flush. Passenger side rear first, no problem.

But when I opened bleed screw on driver side rear, nothing came out

- I removed the bleeder altogether, still nothing.

- Poked a piece of wire through the bleeder opening. Still nothing.

- Slackened the flex hose connection on caliper a turn or so. Still nothing.

- Tried flexing the flex line, but still nothing.

All this with 20-25 psi on pressure bleeder.

So, it seems that either the flex hose or the hard line from tee is blocked. Or maybe the tee itself?

Anyone else had this happen?

I found another "problem" but will post it in the how to remove flare nut thread!

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

the flexible hoses can break down internally. are they old? removing them as you know is a slightly delicate procedure, but no big deal. i'd pull the flex hose off and see if you can get a fluid flow from the hard line

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1981 NA 300D 310k miles

The flex lines were new in 2006 and car has had light use since then. If they have collapsed internally, I would have thought flexing them as I did, would have let a little fluid by. But none appeared.

You are right about next step. But I need to order the flex lines first. Maybe I will first try removing the hard line at the tee and see if I get fluid there. Then take out whole piece and try separating on bench.

If I mess up the flare nut, at least this is an easy hard line to replace. Other side not so easy. But if I change one flex line, I should really change both

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

The flex lines could be on their last legs but it is worth checking that you get fluid coming out of the master cylinder connection to the back line first.

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

I was able to bleed the passenger side, so fluid is getting to the rear and to one side.

Nothing for it but to take the lines apart.

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

Oh crap - at least you've got the gucci tool now

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

I cut the hose at upper end and fluid came out.

It seems that the problem is that the hoses were not quite long enough. When the car is jacked up, the hoses are pulled tight and kink at the bottom (caliper) end. The hoses are same length as Pelican sells (30.5mm/12"). The ones I have coming tomorrow are 31.1mm/12.25". Not much better.

Something to watch when jacking car (and when buying flex hoses.)

Even withe the Gucci pliers, not having much luck with the driver rear. The pliers don't slip, but the 14mm flare wrench does. Tried heat and lots of PBlaster. Tomorrow will try a long reach 14mm socket. Then try removing at tee/distributor end. Eventually we'll get her done!

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

Would a second Gucci tool help?

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

It would have to be a larger one for the 14mm hex. They are better at holding the nut than turning it.

I used a good crowsfoot with 12" bar, on the 14mm and still couldn't get the flare to release. I will try regular vice grips on the flex hose swage and/or a socket. Have to go pick up rear flex hoses and will also get a brake line for the problem side, just in case I need it. Should get one for other side too, but that can wait a day or two.

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

Use a pipe on the 4LW for extra leverage. I ordered one online at Homedepot.com and had it shipped to store for pickup. It is very small. Here it is next to my 5" pipe wrench which has saved my butt many times.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

I can highly recommend the stoptech steel braided lines.

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