V/S 70s -- Thoughts on Preventive Maintenance -- Brakes

Post by **E Showell** » 16 Apr 2015, 06:43

So it occurs to me after needing to replace the original brake hoses on two V70s a 98 and 99 about a year to a year-and-a-half apart, that the original rubber brake hoses have a service life of about 15 years, regardless of mileage.

Current symptoms dictating replacement on the '99 include brakes remaining partially on -- just slight rubbing really -- after application due to suspected collapse of the hoses stranding fluid in the system until the hoses return to their original shape.

So, it would seem prudent to me to plan on replacing original brake hoses after about 15 years.

Anybody else have any thoughts on this?

rhalkyard · Post by **rhalkyard** » 16 Apr 2015, 07:47

I'd agree. I can't imagine that mileage would have much impact on brake hose integrity, but I've owned a long string of 15+ year old cars, and on every one of them, the brake hoses had either already been replaced, or desperately needed it, regardless of mileage.

My 850R actually had one of the front brake hoses blow out about a week after I bought it. Not a terribly pleasant experience.

Post by **erikv11** » 16 Apr 2015, 07:51

My comment would be that the fronts wear out much more quickly, presumably due to constant flexing with the motion of the steering, I think every one of them has been replaced at least once on my cars and I know I have replaced some more than once.

So I would like to follow up with: has anyone ever had rear brake hoses on a P80 that needed replacement from normal wear and tear? My impression is those fail rarely even after 15-20 years. So far.

Post by **E Showell** » 16 Apr 2015, 07:54

Yeah -- but I'm figuring it is brakes. Like the cooling system hoses, do you really want to roll the dice on brakes? Erik?

Post by **erikv11** » 16 Apr 2015, 08:17

I don't understand why the question, what are you getting at?

Maybe it is somehow unclear in my post: I'm indicating that in my experience front brake hoses go bad all the time and need frequent replacement, and wondering if people could also comment to provide input specifically about rear brake hoses, regarding routine maintenance.

Like your innuendo is presumably meant to imply, I agree that brakes are important.

Post by **cn90** » 16 Apr 2015, 09:13

At this age of 15y+, I'd replace:

1. All 3 hoses: 2 in the front and 1 on the LR side.
The hose above the delta link is very difficult, you can leave it alone for now. If you ever replace this particular hose, you need to undo all metal pipe attachment point (the Y-connector on the LEFT side and the RR caliper side). However, the RR caliper nut is known to seize, so remove the metal line and the RR caliper as a unit. This is the least painful way!!!

2. Renew the caliper seal/boots.

Info in the brake overhaul thread...

Post by **mecheng** » 16 Apr 2015, 10:16

Front brake hoses are easy to replace with the proper wrenches and take a beating with all the flexing.

The rear hoses are a major PITA, I can't see any easy way to replace them and knowing how hoses are constructed (double layer) they should be okay. If I'm under the car, I try yearly to spray them with Silicon and the solid lines with Rust Check inhibitor and hope for the best.

Post by **dosbricks** » 16 Apr 2015, 19:10

Like some of you, I left the rear hoses alone. I ordered one set but upon discovering the difficulty factor and finding no bulges or cracks, I wimped out. Just inspecting periodically but no plans to renew them if they continue to look OK.

Post by **abscate** » 17 Apr 2015, 08:20

Cross posting a hint from another thread - align and start union nuts BEFORE attaching the caliper so that both parts can move - it is much easier.

My 1999 needed new hoses after about 10 years - I don't know about the 2005 but I will have a good look at them this weekend. Just did a big roll from ALB NYC BOS at 30 mpg in the 2005...

Post by **cn90** » 17 Apr 2015, 08:58

Further to what I said above...
I "borrowed" this photo from the web to show you how I'd approach the hose above delta link.
This particular hose is impossible to replace in situ.

Since the nut that connects the metal line to the caliper is usually seized over the years of service, the best approach is as in the photo below:

- Step 1: d/c the metal line at the Y-connector (LEFT REAR side).

- Step 2: undo the 2 bolts holding the rear caliper and remove the whole thing (caliper ---> metal line ---> hose ---> metal line) as a unit.

- Then deal with the hose once it is out of the car. You still need to use heat (propane torch etc.) to undo the hose.