no fluid to one new caliper

[Manriquez]

Hi guys, I'm from Chile (the last country south in the map) and few years ago bought a C10 and got her rusted parts replaced/repaired, painted, did throw in a rebuilt 350 and some other things like rims and interiors.

a few days ago during a hard brake the passenger caliper did got jammed (rear I have factory drum brakes), so replaced the both calipers with refurbished units. but when tried to bleed the bad side there was no fluid coming out. as per the problem experienced I wasn't surprised with this. Did check all and found the Master cylinder (that is new) was working properly, lines+ new flexible are good,etc. I was able to isolate the problem: combination valve (pressure going into the metering valve and going out to only one front wheel: driver side, no pressure going out to passenger side).
Again I wasn't surprised due the brake issue experienced days ago. Real problem started when tried to reset the valve: normal bleed (2 people) nor gravity bleed are are working (no fluid at all goes to the wheel). Normal procedure to unjam the valve is a couple of hard stomp to the pedal to get the metering valve loose, but it didn't work.
tried to buy a new one, no joy: good luck trying to find it here! and from US was only able to find the brass after market units that I don't want (as they are different in size and shape ...and nipple size) and that will take forever to get here.


any ideas to get the valve working again? so far I thinking on sending pressure from the caliper to combination valve (actually  i gave it a shoot with the crappy syringe that shops sell but didn't work), I was told compressed air can do the job (get the valve loos) but I;m not experienced with that

or where I can get the correct replacement?
(tried  , Rockauto, Summit, Jegs, ebay )

does not have anything to do with the problem but I'm uploading a picture of the Pickup truck

regards
Pedro

[Engineer]

I can't help but thinking there may be some dirt in the valve preventing it from operating properly.

You may try disassembling it to make sure all the moving parts are free.

[philo_beddoe]

Very nice truck pedro! Looks pretty factory original, keep it that way. Via 'con dios!

[Manriquez]

I can't help but thinking there may be some dirt in the valve preventing it from operating properly.

You may try disassembling it to make sure all the moving parts are free.

I agree rust and dirt may be creating the problem. I have read the valve is not serviceable (which won't prevent me to hammer it apart anyway) so I'm  trying to get a new one

regards
Pedro

[Manriquez]

Very nice truck pedro! Looks pretty factory original, keep it that way. Via 'con dios!

Gracias Amigo

It took a lot of time and money to get that look as the today replacement parts are terrible, for instance

the new grille thye sell iis made out of potty plastic (or worse) so got 2 oldies and some fabrication to make it look ok and accommodate the bowtie logo
the 8" rally wheels are very uncommon here and always beaten, so got a set on eaby and sent them to a lathe to get them straight and round,  blast sanded + powder coated them (twice)

so, don't worry wont air bag her nor install 20" shiny Chinese rims LOL

regards
Pedro

[Jr.]

Pedro try  . (I haven't tried this) but spray it with some carb cleaner and blow the fitting holes in the opposite way that fluid pressure would travel. Normally when that valve is bad you will have no pressure at all.

Sent from my SM-N910P using Tapatalk

[bd]

Pedro, (I haven't tried this) but spray it with some carb cleaner and blow the fitting holes in the opposite way that fluid pressure would travel. Normally when that valve is bad you will have no pressure at all.

Sent from my SM-N910P using Tapatalk

Don't do this!  It can contaminate the hydraulic system and cause rubber parts to swell!

Pedro, how did you determine there was no fluid flow to the right caliper?  Did you loosen lines or just open the bleed valve on the recon caliper?  Are you sure the bleed valve isn't just plugged or that the rubber hose isn't collapsed or plugged?

Combination valves can be partially disassembled and cleaned in fresh brake fluid and alcohol, but be careful with the rubber seals - they are not available for replacement.  Once a seal is removed it can swell, making reassembly nearly impossible.  Avoid using any solvents other than alcohol, and keep alcohol usage to an absolute minimum.

[Manriquez]

Pedro, how did you determine there was no fluid flow to the right caliper?  Did you loosen lines or just open the bleed valve on the recon caliper?  Are you sure the bleed valve isn't just plugged or that the rubber hose isn't collapsed or plugged?

Combination valves can be partially disassembled and cleaned in fresh brake fluid and alcohol, but be careful with the rubber seals - they are not available for replacement.  Once a seal is removed it can swell, making reassembly nearly impossible.  Avoid using any solvents other than alcohol, and keep alcohol usage to an absolute minimum.

Changed the both caliper (see the history on the first post), then  bleed the lines, left caliper was ok, the other does not. the gravity nor helper bleed work. Removed the lines from pump to combination valve and from combination to wheels so I'm positive: pressure goes into combination valve but the outlet that goes to right caliper is dry (again tried helper and gravity bleed).

Decided to bring a replacement brass valve which is the one I don't want (have seen few cars braking terrible after the installation of one of those) but you can not get a new one made in USA. I need to bring them all the way from US (Florida) to Chile, which is a full month, a real PITA. in the mean time the truck will be sat.

I guess I will disassemble the combination valve and see what is inside... if I mess it good, still will have the other cheap unit coming (if anyone knows where to find a GM unit please HELP!).

regards
Pedro