Brake advice needed

[Monocock]

I've cocked up big time!!

Recently changed the undercarriage on my Mk3 to Grove. When reassembling the brake system I wasn't aware that automotive brake fluid was not compatible with Matco brakes. The weather has been poor for four weeks since we did the undercarriage upgrade, and the Kitfox has been sitting there unused. I went to fly her just now and the brake seals clearly don't like the fluid! One is leaking out of the top where the plunger goes in, and the other one has stopped working altogether.

So, my first question is this. Is the Matco MC-1 the standard master cylinder for the original Kitfox Mk3? If so, I see I can buy a rebuild kit.

Secondly, will I need to get new seals for the seals in the brake end too?

Any help appreciated.

[Av8r3400]

IMO, you need to do a full rebuild of all, soft parts, including lines. Be sure to flush all of the "bad" fluid out as much as you can so that there isn't residual in the system to ruin your new parts.

Everything should be available from Matco.

[jiott]

I agree, a total rebuild of all soft parts along with a thorough flush of the system to remove all old fluid. However, I am not sure about the brake lines themselves. Depending on what they are made of you may be alright with just flushing. I would do a check with the supplier of the lines to find out compatibility with the old fluid. If the lines are easy to replace with new then that would be the best option.

[Av8r_Sed]

I do believe the MC-1 was originally supplied with the Model III. That's what I'm currently using. I rebuilt mine a few years ago with the rebuild kit. It's a bit finicky to do it correctly but not difficult. Make sure to treat the rubber boots at the top of the cylinders with dielectric grease. It may be difficult to find any replacements.