1983 GL1100 Brake flush gone bad - linked brake system

[PhotoDoctor]

It was time for my annual brake fluid flush on the 1983 GL1100 linked brake system and now I’ve very little brake from the foot brake. It’s a linked system that I’ve flushed before and I’m not new to bleeding brakes. (It was working pretty well before this fluid flush gone bad)

I started with the right front caliper and have not gotten past this as I was able to pump about 2 ounces through and then nothing no more fluid can be pushed or pulled through the caliper…… it acts like I have a plugged line. I have a vacuum pump and I can no longer pull anything through the line and the right front caliper is not grabbing/braking at all while the rear is grabbing some.

Any thoughts from those with a 1983 GL1100 with the linked brake system?

The good news is that I have plenty of other bikes to ride.

[LAB3]

Does the rear brake still work? If it does then you'll probably find the problem downstream from the pressure control valve. If the rears don't work my bet would be a plugged return hole in the master cylinder.

[julimike54]

I just had the similar experience with my '86 on the front, using the vacuum method. Found the caliper pistons had been pulled all the way in and it stopped the flow to a minimum (as in a drip or so). I resorted to pushing the fluid up from the caliper to the master, then pumped out the pistons by using the rear brake pedal. I'd never had it happen before, but it was the first time I'd ever rebuilt all the brake components. I'm guessing I pushed the pistons too far into the caliper. You could probably push the pistons out by using compressed air at the bleeder or hose connection, just watch the master for fluid spewing out. Next time, if I remember, after assembling the calipers I'm going to use the push air in to get the pistons out where they belong, then hook it all up. Might save me a bit of trouble.....

[PhotoDoctor]

Lab - Yes the rear brake still works so not the plugged return hole.


Junkie - Thanks for the tip, I'll give that a look and see what happens. One would think the master cylinder would have enough force but maybe if there is enough air in the system. Anyway, I'll give it a try and report back..........It may be a week or two before I get back to it. Thanks.

[Sig45227]

This past summer I rebuilt my entire system. Prior to that I had flushed the lines several times and got no better feel out of the front or rear.
This is why I disassembled each caliper and put new seals in. I could not honestly believe the amount of solids and garbage that were in the lines. And large pieces of debris in the calipers themselves. They would never flush clean with the amount of garbage that was in the system. How it got in there I will never know.

[PhotoDoctor]

I've still not gotten back to the Goldwing - I'm just finishing up my 1997 ST1100 and maybe the Goldwing will be next in line.

[Rednaxs60]

If the brake lines are original, may be good to replace after close to 40 years. May look good on the outside but deteriorating from the inside.

[PhotoDoctor]

The 83 is finally getting it's turn in my shop. I've been told this problem has the symptoms of a bad proportioning valve so I'm pulling the system apart. Currently the 10mm fittings that connect the hard lines to the valve don't want to budge so they are soaking with PB blaster. I've also taken a 10mm box and cut a slot out that will fit through the line so I have a better fit than just a 10mm open end. If the fittings round off I think I will pretty much need to split the system so it's no longer linked.

If that happens I may need a rear master cylinder from an 82 model. I think I have everything else that I will need already.. (But I'll give the pb blaster a week or more and see if the fittings will come loose.

[Rambozo]

If they are really tight, you might want to head off trouble with a real flare nut wrench. A cut box wrench won't be nearly as strong and probably not a six point? Another tool that gets those tough ones out without damage is the vise grips made for nuts with the vee jaw.

[PhotoDoctor]

Thanks - I will pick up the wrench set before going at it again.

[LAB3]

You're going to want to heat them too!

[PhotoDoctor]

So The steel lines have not budged yet - However, The rubber hose going to the right front disk is a totally blocked. It appears using the vacuum bleeder when flushing the system was the final straw and Collapsed the rubber line. (Thus it's likely the proportioning valve is fine and doesn't need to be removed.)

Now where to get a new hose for the 1983 linked side? (Maybe I will have to have one made)

[Rambozo]

Now where to get a new hose for the 1983 linked side? (Maybe I will have to have one made)

Check with Randakks. They have a lot of brake lines for Wings, as well as universal lines and adapter fittings.
randakks.com

[PhotoDoctor]

Amazon Hose company in Tampa made a new hose for me while I waited, they used the rubber sleeves and protectors from my old hose - took about 15 minutes total time and $ 37.15 which included tax. The brakes are all good again : )

[Chewy]

So The steel lines have not budged yet - However, The rubber hose going to the right front disk is a totally blocked. It appears using the vacuum bleeder when flushing the system was the final straw and Collapsed the rubber line. (Thus it's likely the proportioning valve is fine and doesn't need to be removed.)

Now where to get a new hose for the 1983 linked side? (Maybe I will have to have one made)

Take the hose off and go to your local O'Reilly's. I replaced the front right, and rear brake rubber lens with automotive hoses from the parts house. They will be able to match length thread size and banjo and get the hoses that you need.

I did this on a friend's 83 interstate, and he is very happy.