Ok, so if you want to get caught up, read the Death Wobble thread, then this one.

John Purnell (from the RRO e-mail list) had gotten me to thinking about tearing in to the ABS pump itself and see what's going on in there...so I did.

I pulled the pump, split it in half, and was amazed at the varnish that was covering everything in there.* Literally everything had a film of brownish goo (dunno what it was, must have been some brake fluid residue or something), and I know that the internal moving parts of the pumping mechanism were stiff.

I dissasembled it down to the pressed in bearing, removed the varnish with carb cleaner and 300 grit sand paper, soaked the inside of the cast housing/bearing with carb cleaner and tried to get all of it out with a small screwdriver acting as a scraper, and have now reassembled the entire thing.*

I reinstalled the pump, bled said pump, then bled the valve block. FYI...there was quite a bit of air in the valve block, so I ran nearly a complete reservoir full of brake fluid through the valve block to clean out the old fluid and any residual air.

The pump did it's normal whining cycle when it was initially charging, then stopped sloooooowly. After I bled the valve block it did not need to re-cycle until 4-5 pumps of the brake (normal in my experience).

So, feeling pretty good I took off down the road to see if everything was working.

60-0 tests repeatedly with full foot on brake proved very sucessful. Pavement panic braking was perfect, gravel panic breaking was perfect, pavement to gravel panic braking was also perfect. No additional whining, no excess re-charging of the system, ABS works as normal.

So...if you call a 30 minute 'extreme' test sucessful, then the pump servicing has proven cheap, effective and easy. Did I mention it was CHEAP?

I am curious what the reddish 'varnish' covering all of the internal pump parts was. I have to confess, I have used DOT3 fluid in the system for a while now. I had to cheat out in the boonies a while ago, and never flushed the system. I wonder if the DOT3 fluid had anything to do with the varnish? I do not think it is rust.

Flushed and refilled system today with Valvoline synthetic DOT4 fluid.

We'll see how long she holds up this time...

Michael

PS I must now eat a little crow...I was hellbent on gutting the system, and then curiosity got the better of me. I would not consider this 'rebuilding' the pump, rather just extending it's life a bit. I still plan to do the non-ABS conversion when I get back from Santa Fe at the end of the month.