mechohaulic

I would go with the R-12 kit 2831, has all the important parts for rebuild. if the piston #4 was cracked the supply air would bleed out through into service can lines which would have a quick release valve leaking POSSIBLY. try a can of spray silicone with flex nozzle spraying into valve from bottom or take off a service line spray into valve. spray in service line not as effective since your spraying on top of piston . before spending $600.oo ; I'd do everything possible to narrow down problem. course have to hope some/any of these kits still available.

be nice to have more specs on it .see two sticks . says 278 engine ; metric numbers ? figured silver/gray interior a repaint = matches steering wheel - Canadian colors ? pretty paint with "sold as is " ?? still nice looking unit ;; thanks

doing that steering box without a helper at the crane controls adds to challenge. if you haven't already removed left side radiator to cab support bar , it might make job easier. engine hoist with a small chain come-along instead of direct engine hoist chain to steering box has advantages too. allows you to stay in the wheel well not have to go back forth to hoist lowering. Swing the box in position then use the come along to lower between frame /radiator shroud. I've been told ; it's important to pay attention to how the chains are hooked to box ; after all the labor to insta[l in proper position you realize :: WTF I can't get to the lower chain to remove it now. so I've been told LOL

so a steering box (major advancement) and rear axle seal; extensive fiberglass work done is still considered accomplishments. if they weren't done the statement would read "didn't get anything done on DM this year"! the Mrs. to do list; yard Maintenace ; a break now and then all takes time.

top face on #6 is a flat rubber washer which 7 out of 10 times is the culprit, either crud or crack in washer if there is a constant leak.

how you connect the chain to the box and hook on hoist makes all the difference also. hooked up so box is close to proper angle when installed . lower into frame ; long bolts/ line up bars . can slide the spacers in when box in position. to hold the spacers, lower box and catch bolts alone P I A .

being a constant leak WITH parking brakes set; I'd go with earlier post I wrote and look at the lower section of that valve. if you have a "helper" a quick check would be to BLOCK the wheels safely; release the parking brake unit having full air pressure and truck shut off ; have someone have their hand on bottom side of leaking valve ; helper in cab step on brake pedal; air leak changes /slows chances are it's the flat rubber diaphragm in valve. to replace bottom kit ::parking brake set ; make sure all air is drained from tanks. larger pair of snap ring pliers (also safety glasses on ) , remove the snap ring .valve assembly has slight spring pressure. important thing air tanks MUST be empty.

another BMT bit of info I never paid attention to ::: duplex right side /tri & quad left. thanks . must be late =have to type with one hand (left) right hand going through shift patterns LOL !! like transmission holder and clean shop

noticed no one questioned WHEN is the valve leaking ;; constant (shouldn't be) ; during service brake application or after service brake applied and released? might make a difference where the hunt starts.

the cab overs will be totally different . hand brake mechanism goes up/down inside with tilting the cab, with cable going to hand brake drum assembly on transmission. the B which assuming is the truck being repaired will have the handle set up bolted to interior floor ;;; linkage connecting to transmission.

thanks for picture helps alot. but with all the electronic wires tied to it can't see the sides. if it's the service brake relay valve = the large line in front (green) is supply; 3/8 line on top is line from treadle/trolly which activates the valve; and there should be two more lines - one on each side going to brake chambers. inside plunger could be dry and sticking or bottom discharge valve has hole in diaphragm

numbers I don't have sorry. almost guarantee the small metal tag which would be on one of the four corner bolts is gone or unreadable,

where you have red circle is the exhaust potion of the valve(forgot to mention). good pair of snap ring pliers will remove bottom half which is flat rubber diaphragm /o-ring ?

can't conceive the prices for this stuff today. 1k for a front brake can; 600 for a valve ????

not to be a bearer of bad news, more to let you know your post is being read : BUT there was a duplex 10 speed / alum rear half at the farm in CT I help out at. went looking for it yesterday for numbers etc== it's gone ' they buried it when fill was brought in or it went to scrap yard with other stuff. the rear end from the Mack still there .

for $600.oo I would take the 4 bolts off the top . remove the alum plunger inside try for a rebuild kit which is nothing more than a 1/8th (+-) in square o=ring that goes on the plunger. a number of situation will give that valve air leak.

the highway definite cause for high BP; having to deal with highway driving now due to new residence; the booze intake has increased.

color scheme might also depend on the use of the truck ;every day runner or parade /toy truck. and don't forget how many $$$ being spent. two tone with pinstriping daily driver going through rain snow/ dust ?

not sure about the carpenter hammer being in the picture ; guess it's safe to say , when it comes to the steering box project :: you nailed it .LOL

where did Mutrie tankers run ? east/west coast ? can't picture them east coast. having mental block of the tanker fleet on east = they were two tone green possibly from jersey ?? , seems there was also fleet use to be a beige/ marron tankers ,

all good things take time. don't take tooo long though; think you might have competition for who's done first== your DM or the new arrival ==U 600T. LOL

I see where you listed the bay state show . a tad closer to CT also. in past has this been a descent show ? in the Baskin delivery days . one stop I had was in N, Attleboro.

be interesting to know actual model ; U -???? T. rear hubs 6 spoke not 5 ? dry air cleaner . profile shows R-487p. R model small diesel ?

If/when you pull center cable out ;up on reinstall you may have to remove cable from drive end verifying inner cable went into the drive adapter and not along side it. should inner not want to fully seat;;; bypassing adapter possibly the issue.

But they are not all criminal repeat offenders::: they just don't like the 40 hr work week.