Hey folks!
So, I've got a 98 land rover discovery with many miles. I recently went to start it up and have 0 pressure in my brakes. Checked under the hood and my reservoir was bone dry and the paint under the master cylinder was bubbled and coming off. I have a fair idea that its leaking from somewhere in that block. Now I'm fairly confident in my ability to replace parts. I've already had to do so and have read several forums/ watched several videos on how to actually replace the master cylinder. So that much I feel comfortable with. My questions for now are. Is it worth getting a rebuild kit to replace the seals on the master cylinder I have or is it better to replace the whole unit? Where's the best place to buy a new one? (I found older forums with this question, but a lot of the links are dead these days, lucky 8 seems a front runner as far as I was able to search) And a final question, is it worthwhile to go ahead and replace the soft brake lines at this time since I will have to bleed the brake system anyway? This last one is more of a personal choice thing but I'm curious about people's opinion of the braded brake cables vrs. standard brake lines, and if it's worth swapping them out before they fail. Some additional info about the rover, I bought it about two years ago off a mechanic who has done a fair share of things to the vehicle including going through the wiring and pulling out a lot of previous "fixes" The guy I bought it from worked at a reputable shop that I had been taking someone of my older cars to for years so overall I trust him and his list of things he has done to the vehicle prior to me buying it. Most of them where the standard maintenance stuff. He lifted the truck and replaced the brake lines at that time, but he built the lines himself, so they were the correct length and what not. That would have been about 7 years ago now for the truck. I appreciate any input in advance. Like I said I've poured through older forums to make some informed decisions already, but a lot of that info is a few years old at this point and parts are become a bit more scarse. I love this addiction... I mean hobby and I've been really thankful that I stumbled on this forum shortly after buying the truck. You guys have helped to keep me calm when stuff goes bad and the detailed write ups have given me extra confidence when wrenching. So once again thanks for all the help you guys give! Happy trails!

 

replaced made mine about 7 yrs ago to due to rusting hardlines. - still working great. - but preping the flanges took some skill and patients - and do overs.
I wouldnt buy anything until you determine 100% where the leak is coming from. the paint bubbles will bring alot of rust- so treat that ASAP - also its a sign of a continuing problem in the system - may not be a bad MC...... but a bad flange on the DIY lines check all the connections.
I got my MC off of EBAY - got lucky it was decent, stay away from cheap after market brands (dorman), they use cheap rubber inside and you will have ghost issues. if possible get one from autozone or a local returnable autostore (I hate ACdelco but that might be your best bet from autozzone)
note in these vehicles when brakes are 100% they are about as good as a 25yr old honda with 25yr old brake fluid......... just so you know....

 

Upgrading to defender calipers (front) is a worthwhile project if you want decent brakes. I've done this to both my D1's and RRC over the past few years. Note the D1 has non-vented disc while the RRC is vented. You can upgrade to RRC vented discs just make sure you buy the caliper for vented discs. Vented fade less so better with heavier loads and towing. Improvement is night and day.

 

Oh, definitely the brakes where not the best thing in the world before. I went to drive it and I have a bit of a hill of a driveway. I put it in drive with my foot on the brake and it started going. Pulled it back into its spot using the e-brake and took a look around. No fluid is making it to the ground so it's not coming from any of the current lines or calipers, just figured since I had to bleed to brakes either way might as well think about changing out the lines. Thankfully the vehicle has little to no rust. I already hit the spots with brake clean and some rustoleum in the meantime to keep things fresh. The fluid is on the bottom of the master cylinder, and it drips off the connector point between the cylinder and the brake booster. The bottom off the reservoir could potentially be cracked. Haven't taken anything apart yet. It's not my main vehicle so I have some time to crack into it. Would just rather buy once cry once kind of thing. I have looked into the defender brakes, but they are a bit out of the budget for now. That was going to be an upgrade later on down the road. It's also to note that I refiled the reservoir to try and get some pressure back in the system to see if it was actively pushing fluid out anywhere with things running, couldn't find any leaks that way but when I went out the next day the levels had dropped, and fluid was once again on the vacuum booster. I have rags sitting under it currently.

 

I replaced th eMaster Cylinder on my '98, well had it done after purchasing a MC from Lucky8, and then couldn't do the work due to weather temps in the belo zero mark. The shop that did it was a reputable place . When I picked it up the next day, it had no brake ressure at all. I walked back inside and they went out to try it. it came right back inside and lines were re-bled. It lasted about 3 months and same thing. I replaced the MC again, same issue after a few months. I sourced a different brand MC and it lasted a year.

Moral is to rebuild the factory one. I wish I did!!

 

Good Knowledge. I sourced a new master cylinder cheaper than the rebuild kits. I horde parts even ones that went back in case I ever have to rebuilt and reinstall so the original kit will stay in case I ever end up needing it. This weekend I plan to start tearing into everything. I have enough knowledge to be dangerous so if you see an oxford blue discovery on the news for the brakes going out know I died doing what I loved. Tinkering!

 

That's funny. I think one thing these truck have going for them is that a lot of things can go bad without being catastrophic.

 

JohnZo: "a lot of things can go bad without being catastrophic"
Love it!

 

So very TRUE! I've had a lot of things happen in my relatively short time owning this truck and none of them made it so I couldn't get home. I feel the brakes may be the one thing that WOULD be the problem. Our driveway has a fairly steep incline. I got in the rover one day to keep it fresh put it in drive and she started rolling and the brake pedal fell all the way to the floor. Yanked the E-brake halfway down and backed it right back up into position. That all being said I do think the o rings between the reservoir and the cylinder itself are what failed not the cylinder itself. So, there's that. I put fluid in it to see if I could build pressure again, but I think I already had air in the lines at that point. All of that fluid has leaked over the course of the week of the truck sitting. I got some nice braded brake lines since I have to bleed the system anyway and ill keep the old master cylinder and maybe rebuild it in my spare time for when the aftermarket will inevitably fail. I did the same thing with the water pump. It's a hobby vehicle so it's been a blast. Hopefully It will be reliable again come the uwharrie opening. I'm ready to finally get it on a trail.

 

My '98, it was the seals under the reservoir that leaked in cold weather. If the tank is empty, hitting the brakes will put air in the lines and they will need to be bled.