JHZR2
Staff member
On my 2008 ML320 diesel, I had noted that there was some chafing on the front brake hoses. I also have all of the service receipts from the previous owner and I knew when I bought it that a prior shop had noted the brake hoses needed to be replaced.
I set out to do the front this weekend, and the connections at the hard line were definitely iffy. The first one I did, I was able to get loose without straining the line, however, once I started to fully remove it, the line bent and started to leak. I could feel that the coating on it was fully damaged, and I guess it was just enough shearing from turning the fitting to cause the line to leak at a weak spot. The female fitting for the soft line is locked in place and unable to turn.
So I had this after trying to crimp and bend it to stop dripping:
Unfortunately, Mercedes no longer supports these lines. I have searched for the part number. I’ve been unable to find one. Apparently they’ve been discontinued and now Mercedes sends a coil of line with the appropriate fittings for a shop to flare and install. The factory service manual also provides the following, shown under a fair use doctrine:
Based on my understanding of reading elsewhere, and the first section of this manual, the union is allowed to be used as a repair, as long as the F flare is utilized. I assume that the DIN number is for what others call a bubble flare.
So I’m looking for advice on what to do. Usually I don’t buy cars that has spent their life in salty areas. New Jersey isn’t too bad, and the car is beautiful otherwise. But this is an area that is exposed to extreme wash, and obviously has suffered corrosion. So I should execute under the assumption that I will be doing at least four repairs, either complete or partial.
So my issues are as follows:
1. It seems like the best flaring tools and dies require placement into a shop vice. How viable is it for a newbie to cut a line that is already on the vehicle, flare it, with a new male fitting, and then install it into a union? Is there a F type flare die that is better for use in situ?
2. Bel metric and others offer premade flared lines which I would assume would be pretty perfect. For the current install at the front left I wouldn’t see an issue at all. I’m sure that I can route the hose so that it goes from the ABS pump to the standard location without much of an issue. However, see my assumption above. I’ll guess that at some point I’ll need to do all, and I have no idea if there’s already a union someplace in that system. So is it better to just bite the bullet and start to do the path mentioned in number one?
3. Regardless, I will need a decent tubing bender, and potentially one that is small enough to use in place. There is essentially a drip leg shaped like a J at the bottom of the hard line where it connects to the soft line. So I need to be able to make essentially full reversal in tight diameters in order to refit a line.
4. This is a job where to be frank, I’m not sure that I’ll have to do too many times. My older vehicles don’t see salt, and my new vehicles get rinsed and protected quite often. So I kind of have to wonder if it’s worthwhile to buy all the tools and parts and do this or just to form it out to a shop. I have a Jaguar specialist just a few blocks away from me, so I kind of think that it may be worthwhile to have them do the job and just handle all four corners in the interest of safety. But that means I have to get the vehicle backed out of my driveway safely down the street and into the shop. I was able to use a pair of sign cutters to crimp the line almost completely to prevent gravity flow. However, I doubt that it will do anything against actual pressurized flow. It will make a giant mess the second that I step on the brake pedal to start the vehicle. I need to start the vehicle to get out of my driveway. So, is there some kind of a cap that would be recommended that will allow me to do this, knowing that I will only have three blocks to go? I’m thinking maybe a Swagelok type cap fitting - something that doesn’t require me to have special tools, which would defeat the purpose of having a shop do the work, So is there a decent way to prevent complete loss of fluid And some level of use of brakes to go to a few blocks to the shop?
Thanks!
I set out to do the front this weekend, and the connections at the hard line were definitely iffy. The first one I did, I was able to get loose without straining the line, however, once I started to fully remove it, the line bent and started to leak. I could feel that the coating on it was fully damaged, and I guess it was just enough shearing from turning the fitting to cause the line to leak at a weak spot. The female fitting for the soft line is locked in place and unable to turn.
So I had this after trying to crimp and bend it to stop dripping:
Unfortunately, Mercedes no longer supports these lines. I have searched for the part number. I’ve been unable to find one. Apparently they’ve been discontinued and now Mercedes sends a coil of line with the appropriate fittings for a shop to flare and install. The factory service manual also provides the following, shown under a fair use doctrine:
Based on my understanding of reading elsewhere, and the first section of this manual, the union is allowed to be used as a repair, as long as the F flare is utilized. I assume that the DIN number is for what others call a bubble flare.
So I’m looking for advice on what to do. Usually I don’t buy cars that has spent their life in salty areas. New Jersey isn’t too bad, and the car is beautiful otherwise. But this is an area that is exposed to extreme wash, and obviously has suffered corrosion. So I should execute under the assumption that I will be doing at least four repairs, either complete or partial.
So my issues are as follows:
1. It seems like the best flaring tools and dies require placement into a shop vice. How viable is it for a newbie to cut a line that is already on the vehicle, flare it, with a new male fitting, and then install it into a union? Is there a F type flare die that is better for use in situ?
2. Bel metric and others offer premade flared lines which I would assume would be pretty perfect. For the current install at the front left I wouldn’t see an issue at all. I’m sure that I can route the hose so that it goes from the ABS pump to the standard location without much of an issue. However, see my assumption above. I’ll guess that at some point I’ll need to do all, and I have no idea if there’s already a union someplace in that system. So is it better to just bite the bullet and start to do the path mentioned in number one?
3. Regardless, I will need a decent tubing bender, and potentially one that is small enough to use in place. There is essentially a drip leg shaped like a J at the bottom of the hard line where it connects to the soft line. So I need to be able to make essentially full reversal in tight diameters in order to refit a line.
4. This is a job where to be frank, I’m not sure that I’ll have to do too many times. My older vehicles don’t see salt, and my new vehicles get rinsed and protected quite often. So I kind of have to wonder if it’s worthwhile to buy all the tools and parts and do this or just to form it out to a shop. I have a Jaguar specialist just a few blocks away from me, so I kind of think that it may be worthwhile to have them do the job and just handle all four corners in the interest of safety. But that means I have to get the vehicle backed out of my driveway safely down the street and into the shop. I was able to use a pair of sign cutters to crimp the line almost completely to prevent gravity flow. However, I doubt that it will do anything against actual pressurized flow. It will make a giant mess the second that I step on the brake pedal to start the vehicle. I need to start the vehicle to get out of my driveway. So, is there some kind of a cap that would be recommended that will allow me to do this, knowing that I will only have three blocks to go? I’m thinking maybe a Swagelok type cap fitting - something that doesn’t require me to have special tools, which would defeat the purpose of having a shop do the work, So is there a decent way to prevent complete loss of fluid And some level of use of brakes to go to a few blocks to the shop?
Thanks!
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