Can a mt2500 cycle the brake dump valve?

[man-a-fre]

I am trying to find a way to cycle my 1994 rwal brake dump valve on my k1500 5.7 auto wondering if a mt2500 can do it . Low brake pedal running with vac boost not real firm no low enough to trip brake light ,nice high pedal not running and firm.

 

[Schurkey]

I'd test mine on the '88 K1500 with the Kelsey-Hays RWAL...but I think my MTG2500 finally died.

Well, murdered, actually. I spilled gasoline on the thing, and the gas got inside the case. Screwed-up the screen, too.

Does your RWAL have a bleeder valve? My '88 does.

 

[man-a-fre]

No bleeder thaty i see , its a difeerent style than 88 . I am fighting a low brake pedal and I think it is the isolation dump valve. The pedal is fine before i start the engine then with boost it sinks alot,not enough to turn brake light on but I would prefer it to be half way down , not to the floor. New pads and shoes ,drums adjust to slight drag , new master cylinder bench bled,2 new rear wheel cylinders . Pedal bled with no sign of air and plenty of pressure it seemed then gravity bled also for the heck of it ,no change after all this. I didn't want to put the new nbs style master cylinder on but I may need to, may take dump valve out and put line right to proportioning valve and try that since I cant seem to get it to cycle if it does have air . This brake deal sucks, I mean it stops but there isnt much cushion before the pedal hits the floor.

 

[PlayingWithTBI]

Well, murdered, actually. I spilled gasoline on the thing, and the gas got inside the case. Screwed-up the screen, too.

Bummer! Time to find a Solus, huh? There will probably be a bunch for sale by the end of the year,

OP - can't you use a vacuum bleeder to get the air out of the system?

 

[studigggs]

I am trying to find a way to cycle my 1994 rwal brake dump valve on my k1500 5.7 auto wondering if a mt2500 can do it . Low brake pedal running with vac boost not real firm no low enough to trip brake light ,nice high pedal not running and firm.

For RWAL, no, there is no way to cycle or command anything with the MT2500, Modis, or Solus. Read codes only. I've heard tell that you should find a gravel road, and do some hard braking to cycle the RWAL.

 

[Schurkey]

I didn't want to put the new nbs style master cylinder on but I may need to,

VERY BAD IDEA.

Any vehicle with low-drag calipers should NOT be downgraded by removing the quick-take-up master cylinder.

Look at your glovebox decal, figure out what brake system you have (JB5, likely.)

Bummer! Time to find a Solus, huh? There will probably be a bunch for sale by the end of the year,

Yeah. I'm gonna have to see if the gasoline has dried-out yet, and try firing the thing up to see if it's toast. And then, see how bad the screen damage is when it's in use.

I've got several Soluses (Soli?) on my eBay watch list right now.

For RWAL, no, there is no way to cycle or command anything with the MT2500, Modis, or Solus. Read codes only. I've heard tell that you should find a gravel road, and do some hard braking to cycle the RWAL.

The advantage with RWAL is that if you activate the ABS, you know which channel you've activated--since there is only one.

The 4-wheel ABS on the gravel road might activate one or two channels, perhaps all three--but you won't know for sure.

 

[PlayingWithTBI]

I've got several Soluses (Soli?) on my eBay watch list right now.

Or Solusi?

 

[man-a-fre]

Shurkey I think you were the only one on the planet that still has one of the mtg2500 graphers that still worked , my display on mine went haywire two weeks after i bought it. Had good luck with the mt2500 though but have not used it a bunch. I will not put the nbs master cylinder on,leaning toward changing the rear wheel cylinders to ac delcos instead of the wearever ones i put on. Thinking they could be drawing air even though when i pedal bleed i see none.

 

[Schurkey]

My MTG was slow to boot. Seemed like it needed to be plugged-into the vehicle power for a while before it would "wake up" and work. Maybe this was because the "rechargeable" battery was a piece of trash...but even when the battery was freshly-charged, it still took forever for the thing to boot in summer, and in winter it was ten times worse.

I figure there's something wrong, and has been for years and years...but given five or ten minutes, half-an-hour in the winter, I got what I needed from it; and the graphing worked as well as it was designed to.

But yeah, at this point I'm almost hoping it's toast so I have an excuse to upgrade. Since I've never held a Solus-family scanner in my hand, I don't really know what to upgrade TO. Kinda resistant to buying a scan tool that runs on Microsoft's crappy software. That's another whole set of potential problems.

 

[man-a-fre]

I like my mt2500 have the 9.2 version primary black programmable and 8.2 version troubleshooter good to 2008, thats newer than I ever plan to have in my fleet.