M trailer Master cylinder / brake line

Paul S · Post by **Paul S** » Mon Apr 14, 2008 7:10 am

Been having issues with the brakes on the trailer.

I tried to get the brake line off the master, but couldn't get any of my wrenches to fit (all I had were too big or too small). Anyone know what the size of the brake line fitting is?

Paul

Brian26x · Post by **Brian26x** » Mon Apr 14, 2008 1:59 pm

Sounds like it's metric.

Catigale · Post by **Catigale** » Mon Apr 14, 2008 7:55 pm

I think my 14mm brake wrench fit on mine, but Im 3000 miles from the boat at the moment.

Paul S · Post by **Paul S** » Tue Apr 15, 2008 4:37 am

the smallest wrench I have is a 10mm in metric and it is still too big. Of course, plan B is to just replace the whole freaking line ..but that would be a major pain, but not impossible.

Bawgy · Post by **Bawgy** » Tue Apr 15, 2008 7:50 am

Adjustable wrench . I do have some 4,6 and 8 mm i use in my bike shop. If you cant get it I will take them home and see which one fits

Paul S · Post by **Paul S** » Tue Apr 15, 2008 8:35 am

tried adjustable - wont fit inside the tounge.

Bawgy · Post by **Bawgy** » Tue Apr 15, 2008 8:43 am

O K I will take some home tonight .

Post by **Hamin' X** » Tue Apr 15, 2008 9:00 am

I'm not much help on the size, as I am not familiar with the M trailer. However, do not use an adjustable wrench of any kind. Also, do not use a regular open end wrench. With either, you are almost certainly going to round off the fitting. These are flare type fittings and being in an exposed environment will be extremely tight. Once you have determined the correct size, obtain a line wrench of the proper size. This will contact the fitting on four of it's six sides, instead of only two. If you round off the fitting, your choices are limited.

1. Vise-grips and replace entire line.
2. Leave line in place and hope you have not loosened the fitting.

Good luck.

Rich---Hamin' X---N7ZH

Bawgy · Post by **Bawgy** » Tue Apr 15, 2008 9:33 am

Very good pointd Hammin

Paul S · Post by **Paul S** » Tue Apr 15, 2008 9:35 am

Hamin' X wrote:I'm not much help on the size, as I am not familiar with the M trailer. However, do not use an adjustable wrench of any kind. Also, do not use a regular open end wrench. With either, you are almost certainly going to round off the fitting. These are flare type fittings and being in an exposed environment will be extremely tight. Once you have determined the correct size, obtain a line wrench of the proper size. This will contact the fitting on four of it's six sides, instead of only two. If you round off the fitting, your choices are limited.

1. Vise-grips and replace entire line.
2. Leave line in place and hope you have not loosened the fitting.

Good luck.

Rich---Hamin' X---N7ZH

yup, done brake lines before

Just trying to find out what size I need. My standard size line wrenches were all too big

K9Kampers · Post by **K9Kampers** » Tue Apr 15, 2008 12:42 pm

Paul - On my X trailer, a 3/8 Flare Nut Wrench works.

Catigale · Post by **Catigale** » Wed Apr 16, 2008 4:25 am

A 10 mm is just a smidgen bigger (393 decimal vs 375) than a 3/8 inch SAE, so im guessing it is a 3/8 SAE

A 10 mm will work but it will also round off those nut corners and make your life miserable later.

Paul S · Post by **Paul S** » Wed Apr 16, 2008 7:03 am

K9Kampers wrote:Paul - On my X trailer, a 3/8 Flare Nut Wrench works.

Nice your brake line is 'right there'. The M is inside the tounge! Very hard to get to.

If I can't get it off.. I might just bite the bullet and do a new line and entire guts of the actuator (about $200 or so) instead of dicking around with the Master cyl and the shock inside the guts. From what i can see it is pretty rusted inside. I sooo hate working with brake lines (having a boat on the trailer at the same time sure isn't going to help!)

I will try the 3/8 flare wrench again, but I think it was a hair too big

MacGregorSailors.com

MacGregorSailors.com

M trailer Master cylinder / brake line

M trailer Master cylinder / brake line