1989 Mack RW-613

[mechohaulic]

if the unit has a trolley valve and truck is in bob=tail mode, the tractor protection valve won't effect brake operation, with the shuttle valve working the slightest pressure on trolley will STILL activate the brake lights but NOT the brakes.

[mechohaulic]

might be alot easier to take the feed line off the trolley in cab then lines off brake valve. trolley three lines 1-supply(constant air) 2-supply( air to shuttle valve on brake pedal ). 3 exhaust port (out to fire wall.

[mechohaulic]

1 minute ago, mechohaulic said:

might be alot easier to take the feed line off the trolley in cab then lines off brake valve. trolley three lines 1-supply(constant air) 2-supply( air to shuttle valve on brake pedal ). 3 exhaust port (out to fire wall.

forgot the simple part (i'm old).before taking any lines off just work the trolley to see if it was partially pulled.if it wasn't THEN take off the line check for air going through.also  if there was another air back feed on the treddle valve the valve SHOULD have an air leak out the bottom (exhaust port ).

[mechohaulic]

11 minutes ago, mechohaulic said:

might be alot easier to take the feed line off the trolley in cab then lines off brake valve. trolley three lines 1-supply(constant air) 2-supply( air to shuttle valve on brake pedal ). 3 exhaust port (out to fire wall.

error===2 is not supply; 2 is delivery. 

[Jeff747]

Trolly brake was the fix. I appreciate you sharing this advice, you saved me a ton of time and money for a simple operator error. 

Cheers, 

Jeff 

[85snowdog]

Thanks so much for sharing your fix. 

So many times people ask for advice and never come back to say what the problem actually was. 

We are very fortunate to have some very knowledgeable folks on here willing to help. 

Would it be possible to see your RW   We love pics 

 

[Vladislav]

I belive the truck Jim posted the pic of was property of Leslie Eversole who used to be a moderator on here a while back.

Edited February 5, 2022 by Vladislav

[Mark T]

On 2/4/2022 at 10:55 AM, 85snowdog said:

Thanks so much for sharing your fix. 

So many times people ask for advice and never come back to say what the problem actually was. 

We are very fortunate to have some very knowledgeable folks on here willing to help. 

Would it be possible to see your RW   We love pics 

 

Pictures are like the currency for info. We all love pictures

[tjc transport]

On 2/4/2022 at 10:55 AM, 85snowdog said:

 

Would it be possible to see your RW   We love pics 

 

as said,