Question about pressure relief valve on FT500 Hale on Deuce and a Half fire truck

[scootertrs]

Makes you wonder why front mounts werent more popular.

Not really... those a normal person with mediocre capabilities could fix... life would be ... well... indefinite... as long as parts were available... Thus, how many new sales would there be? I am sure I have exhausted several lifetimes of our deuce and a half. When you speak to some equipment manufacturers seeking info about trucks that are over 10-15 years old, they want to know if this truck is in a club or a museum, and are quite surprised to learn that it still is working as a fire truck. Regarding the front mounts, I worked on a k3500 chev truck with a front mount a while back... a spectacular performer and could be fixed in the field if necessary... a must for an open woods fire truck... I just have a problem with design engineers that have never turned a wrench and then go and build a wonderful piece of machinery from the inside out. Repairing one of the early assembly components many times requires dissassembling half of the machine to get to it... that is not new BTW... I putt a 1947 Indian Chief and even back then Indian made it tough to get some stuff done... for example... the detent ball on my shifter needed tightening... I can see it no problem... but to get the wrench in, I would have to remove the chain guard... no problem... but to remove the chain guard, I had to remove the exhaust pipes, ... no problem... but to remove the exhaust pipes, I had to remove the kick starter and the floorboards... no problem... and so on and so forth... pretty soon I had half of the motorcycle on the ground to make a 30 second adjustment... but I digress... replacing the packing was a BIT%$... and I may have been responsible for clogging the volute aperture to start with!!! I left one of the packing washers in the pump by mistake... to replace the packing requires removal of the gear box and 10 inch long very thin fingers with telepathic abilities if it is to be attempted while mounted in the truck... and the best part is... this is one of the easiest ones I have worked on!!! Lets hope I got it righht this time.

[neiowa]

Get over to www.steelsoldiers.com There are several guys there that have restored these trucks. Have not been out of the system that long.

Someone will send you a pdf of the mil manuals if they have not already been posted.

[scootertrs]

Get over to www.steelsoldiers.com There are several guys there that have restored these trucks. Have not been out of the system that long.

Someone will send you a pdf of the mil manuals if they have not already been posted.

I have the manual, but not really very detailed when it comes to the fire system.

[neiowa]

I have the manual, but not really very detailed when it comes to the fire system.

As stated there are guys there who own and work on the old duece fire trucks that will be happy to help you.

There are seperate TM for most specialized bodys that were mounted on the M series trucks. The -24 and -24P will likely be the most useful to you.

[scootertrs]

Thank you. I have received many, many helpful bits of advise from SteelSoldiers and have helped others in similar situations. There are some issues that are "fire truck site" specific and I thought more apprepriate to pump issues than SS(obviously correctly-if looking at the type of answers I received here).

I have the specialized manual for the Fire Truck body version, but when it gets to the pump breakdown and internal... it stops. Through help from SS, Hale, and members of this site, I think I have enough to get it done.

Thanks

Raul

As stated there are guys there who own and work on the old duece fire trucks that will be happy to help you.

There are seperate TM for most specialized bodys that were mounted on the M series trucks. The -24 and -24P will likely be the most useful to you.

[scootertrs]

Guys, thanks for making me re-look for the manuals... found 2 that are quite detailed. The parts and tools manual is TM 5-4210-205-35P and the depot dervice manual TM 5-4210-213-35. She is now drafting and pumping like new.
Thanks again
Raul

[kuh shise]

Raul:

Glad that you were able to correct the plugged line and are now operating correctly. Sorry about dropping out of the conversation for the past week. Had to prep for a Train the Trainer session at a Community College. I'm not too proficient at powerpoint and Had to decide on content and hands on problems for the class. We have a 1917 American LaFrance Type 40 with a Junior pump that still operates, so I can appreciate the satisfaction when you are able to solve a perplexing problem. Thanks for the message, I'll keep the info just in case I get to go in your direction.

Kuh

[scootertrs]

BTW guys, if anybody needs the manuals for the deuce and a half M35A2 fire truck, (or bloddy knuckle knowledge) just PM me or better yet, send me an email at scootertrs@aol.comma. I don't think there is much in this truck that we have not had apart... at least once!

[scootertrs]

Was only able to get basic packing cooling and anytime I tried to get a drip, would lose all prime and all pressure when drafting. Took all apart ... again... and took pictures of every component as disassembled. I enclosed a picture of the packing area with just one section of packing and one half of the lantern washers installed. When the second lantern washer is put in its place, the volute hole is almost completly blocked. The packing that was originally in this truck was totally destroyed, indicating that this problem was probably there before we took it apart. I suspect that if the prior FD was running off hydrants, they would not have much of a problem running the packing a little loose... thus it worked, but when you have to get a draft... forget about it!!! We plan on bushing the seat for the packing up so that when it is in place, the volute will sit in the middle of the lantern washers. Thanks again Kuh... looks like you were right all along... just could not see the darned thing... once it was apart, it all looked good!!! I actally went back through all of the emails and manuals and knowing that I had to get water from somewhere and it had to go somewhere else... we even made sure that the volute hole was clear... but could not imagine it getting blocked during assembly... it took a while... but I am optimistic we got it. Getting ready to do another identical pump and noticed during disassembly that the volute, while not completly blocked by the lantern washers, it is definitely partially so... From now on, during disassembly and assembly of every pump... NOTE TO SELF... check the volute hole and its position in relation to the lantern washers...

[kuh shise]

Scooter: Take a dial indicator and try to measure the depth of the packing gland to the shoulder where you are contemplating placing the bushing. Is it possible that there is supposed to be two pieces of packing before you insert the lantern ring? I know there is little chance that Hale will have the dimensional drawing for this pump, but I can't believe that their original machinist cut this bore too deep when it was made. As you see this is a critical dimension and was probably checked with a go - nogo plug type gauge when it was made. The other thing that might have changed over the years is the width of the packing material, but with only one ring ahead of the lantern ring, it is not so likely.
Take a mike or dial indicator and measure the width of the half lantern ring. Then check the distance from the extreme bottom of the packing gland to the center of the hole for the water coming to the lantern ring. Subtract the width of the half lantern ring, and compare this difference with the width of the packing you are putting in the bottom. You will get some compression in the width as the packing deforms and is squeezed down upon the shaft. Allow .015 to .035 per ring for compression when the packing is properly adjusted. Awww, You get the idea...Just make sure the lantern ring is in the right place.

PS: I would like permission to use the photograph in my pump classes and presentations, if possible.

[scootertrs]

Thank you for getting back to me. I will try to respond per event.,..

Scooter: Take a dial indicator and try to measure the depth of the packing gland to the shoulder where you are contemplating placing the bushing. Is it possible that there is supposed to be two pieces of packing before you insert the lantern ring? I know there is little chance that Hale will have the dimensional drawing for this pump, but I can't believe that their original machinist cut this bore too deep when it was made. As you see this is a critical dimension and was probably checked with a go - nogo plug type gauge when it was made. The other thing that might have changed over the years is the width of the packing material, but with only one ring ahead of the lantern ring, it is not so likely.

As is, with the factory replacement packing kit, if I use the 7/16 packing as from Hale - the volute hole is basically where I showed you in the pic. lantern ring falls either right on top of the hole or right behind it... forcing all volute water into the packing. The dimensional diagram provided by Hale shows one piece of packing, one lantern ring, then 2nd lantern ring one piece of packing, one sacrificial shim, one piece of packing, one sacrificial shim, one piece of packing, packing gland

Take a mike or dial indicator and measure the width of the half lantern ring. Then check the distance from the extreme bottom of the packing gland to the center of the hole for the water coming to the lantern ring. Subtract the width of the half lantern ring, and compare this difference with the width of the packing you are putting in the bottom. You will get some compression in the width as the packing deforms and is squeezed down upon the shaft. Allow .015 to .035 per ring for compression when the packing is properly adjusted. Awww, You get the idea...Just make sure the lantern ring is in the right place.

Done it... takes a spacer that is almost 1/4 inch thich-that sits the volute at the very edge of the volute hole w/o compression... with compression, the volute should be right in the center of the lantern rings.

PS: I would like permission to use the photograph in my pump classes and presentations, if possible.

Have at it Kuh. I know we are using it for training at our facility. If it saves just one more disassembly... I have many more where that came for. I can send you a sequence of the disassembly where eventually it will show the problem. Let me know if you want it sent direct and if so, where to. You are free to use as you please. Just try to embarrass me as little as possible
Thank you-You know, I was wondering if a packing is installed, set and adjusted, then something happens that requires disassembly can I reuse the packing (even if it has no hours of use-but was tightened to drip specs? Or is it like a plumbing npt fitting... you tighten to position, if you go past where you want it, you really cannot back to the plqce where the angle is right, you have to go through another 360 degrees until it is right where you want it. I tell you the more I learn, the more I need to learn!!!)

One thing I do know for sure, all of these jobs would be much more difficult if we did not have access to the wealth of info here Thanks again