5 ton fuel tank selector valve cleaning/rebuild

[tractors0130]

Dash primer will not hold pressure since it will bleed off for starting while glow plug is energized.

 

[USAFSS-ColdWarrior]

Finally finding time to tinker with the XM818.

With new batteries in her all the electrical seems A-OK. Even confirmed she has power to the Fuel Solenoid. So now chasing the fuel system.

The EMERGENCY Fuel Cut-Off Cable and Valve are both functioning properly and I've confirmed the Fuel Cut-Off Valve is in the "Run" position.

Primer Pump would hardly budge the Fuel Pressure Gauge's Needle, so I replace the Primer Pump's O-Rings. Now the Primer Pump will make, BUT NOT HOLD 30 P.S.I. with vigorous pumping..... even without cranking the engine AND without the glow plug energized.
Looks like it's on to the Selector Valve and Rubber Hose inspection/replacement as my next indicated step(s).

THANK YOU for the wealth of information archived in this thread. More on this as we progress towards "The Shepherd's" RESURRECTION !!!

Dash primer will not hold pressure since it will bleed off for starting while glow plug is energized.

Thanks for that input, tractors0130.

I added the BOLD and UNDERLINED condition into the quote above. I should have included that detail originally. The fuel lines simply do not hold pressure, seemingly indicating leakage somewhere else.

 

[Rogarner]

I'm working on my M817 with dual tanks and selector valve, My question is about the return fuel line coming from the engine, dose it swap from tank to tank as you draw from the left or right tank? Common sense would lead me to believe it's got to work that way. If not the return line would over fill one tank or the other. I've done a good bit off digging and couldn't find anything about the return lines on a dual tank setup. So I was thinking maybe some of you guy that have rebuilt the selector valve may know the answer to my question. Thanks

 

[doghead]

Yes


Sent from my iPhone using Tapatalk

 

[86m1028]

Wanted to say thanks to this post.
Just picked up hose & o-rings.
Spent just under $30 for enough hose to replace all 8 hoses & they threw in the o-rings for free.
Now to go install it.

 

[gstirling]

Joesco - I just replaced my fuel filter (m936a1) and had a hard time getting fuel back to the engine. first air leak was at the bolt on the top of the filter - found this as it leaked fuel at first. then my priming pump quit working - and it was the second air leak source (I think). once I replaced the two O-rings in the manual prime pump, and refilled the fuel line - it fired right off, if it fires off tomorrow (i.e. fuel line does not drain down over night), then I will be certain I have found all the air leaks. good luck.

 

[msgjd]

Haven't seen any mentions in this or other threads about the Anderson Brass Co. They made valves for the M809-series. They do sell the complete valves, and many of other designs. They also can provide you with the small internal parts. A couple years ago I needed a couple new stop-washers, the ones you see under the handle that limit handle travel. They sent them pronto, never bothered to invoice me nor ask for postage. I have also purchased different valves from them for use on custom projects. And as far as M809-series fuel hoses to/from the selector valves and the hose from the filter to the PT (injection) pump, I stopped buying NOS hoses due to their age. Most auto supplies or truck shops have Gates or equivalent diesel or biofuel-rated hose by the foot. The brass fittings on the M809-series are barbed and are re-usable. The originals might look crimped or special, but they are not. Just cut the old rubber hose off the fittings, and slide the new hose in place and you're good to go. Just make sure the hose bore has been flushed clean after initial hose assembly before you hook it up to your truck

 

[dstang97]

What happened to the part numbers that were listed in this thread. They were pushlock and had part numbers to discounthydralichose

 

[patracy]

Please use the classifieds when trying to sell items.

 

[ldmack3]

Haven't seen any mentions in this or other threads about the Anderson Brass Co. They made valves for the M809-series. They do sell the complete valves, and many of other designs. They also can provide you with the small internal parts. A couple years ago I needed a couple new stop-washers, the ones you see under the handle that limit handle travel. They sent them pronto, never bothered to invoice me nor ask for postage. I have also purchased different valves from them for use on custom projects. And as far as M809-series fuel hoses to/from the selector valves and the hose from the filter to the PT (injection) pump, I stopped buying NOS hoses due to their age. Most auto supplies or truck shops have Gates or equivalent diesel or biofuel-rated hose by the foot. The brass fittings on the M809-series are barbed and are re-usable. The originals might look crimped or special, but they are not. Just cut the old rubber hose off the fittings, and slide the new hose in place and you're good to go. Just make sure the hose bore has been flushed clean after initial hose assembly before you hook it up to your truck

Just an FYI. I've got a deuce with 2 tanks and a 5 ton selector valve. It was very hard to turn so I took it apart and cleaned it up (gently) and now it leaks around the stem. Spoke to Anderson direct this AM. Now they won't have anything to do with the internal parts for liability reasons. I see where I need a #9 & 23 o ring but am still looking for the lube they specify in the velve info. Any ideas?

 

[msgjd]

Just an FYI. I've got a deuce with 2 tanks and a 5 ton selector valve. It was very hard to turn so I took it apart and cleaned it up (gently) and now it leaks around the stem. Spoke to Anderson direct this AM. Now they won't have anything to do with the internal parts for liability reasons. I see where I need a #9 & 23 o ring but am still looking for the lube they specify in the velve info. Any ideas?

sorry to hear they no longer will sell internals .. As for lube, I have used a light coat of vaseline and also regular grease . Yes it will eventually dissolve into the fuel as it's being moved one way or the other, but how soon it dissipates depends on how often you use the valve, as you probably can figure .. I have used o-rings matched up from the local auto supply assortment , not perfect but really close and they worked .. you might get lucky by coating the stem and your old o-ring with a thin layer of vaseline for now .. if you haven't already been, its also a very good thing to get some sort of lubricity into your fuel these days

 

[Csm Davis]

Coat your O-rings in silicone grease it won't damage the rubber but I would suggest viton O-rings to protect from this "new diesel".

 

[swiss]

Got to love old good write ups!!!

 

[AMGeneral]

I’m glad this short write up has helped over the years.

 

[Bearkiller]

I decided to cover the cleaning /rebuild of the fuel tank selector valve

Thank you so much for doing this.

I have been running 4-position/3-tanks Weatherhead valves for years and have never before been able to find any information anywhere as to how to service and repair them.

It appears the valve you show in your photos is very similar to the ones I use on my long-hauling F-350; I use two separate valves; one for Draw and the other for Return.

When new, my valves can be turned easily; however, after the first six months or so, they start tightening up and getting harder and harder to turn until I become afraid to try to turn them, else the stem will snap off.

I have actually had two stems to break when changing tanks; leaving me not knowing just what position the valve may be at.

I had one stem snap off going around the Atlanta Bypass with a big load of cattle that had me laying flat on my back under there with fuel pouring in my face while I physically bypassed the valve by adding a straight-through barb connector; it was that episode that convinced me to only ever use JIC adapters on the valves with mating JIC swivels on the lines AND Ball-Cut-Off Valves in the lines ahead of the selector; you would be amazed at how rapidly fuel can siphon out of a big tank and pour on your person while you are quickly trying to swap from one barb to another.

Before someone tells me I should add lubricant to my fuel, there is an ounce of two-cycle oil in every gallon of fuel that passes through these valves, plus all the used oil that gets dumped in there.

With the knowledge I have gleaned from reading and rereading this thread, my intentions are to remove and disassemble and hopefully get the current two valves on my truck working good as new again.

I did once try a single two-level valve that switched both Draw and Return with each movement; however, there is a lot of stress on that skinny little stem even switching a single level valve; the stem will snap for sure when being so long and having to rotate two valves instead of one.

If I can find all the old valves I removed over the years, I will over-haul them as well.

As for lubing the internals, I am going to look into the possibility of adding an Alemite on that back side where there is no port so that I can give it a shot of grease occasionally.

Are you familiar with the 4-position Weatherhead; I think Anderson and Moeller make identical valves to the Weatherhead, Everco as well, among others.

I believe whatever I find under that top nut will look a lot like what I am seeing in your photos.

Before finding this write-up, I had always thought there was a big shiny ball hidden in there, just like the Ball-Cut-Off valves in the plumbing department; I was quite surprised to see just how they actually are made inside.


If my Alemite idea works out, if a person only had two tanks to switch, they would be advised to use a 3-tank/4-position valve instead, using only the two opposing inlet ports and adapt the center inlet port to accept an Alemite; thus, they could circumvent the need to drill/tap.

As I am new here, is it allowed to put an Amazon link to an example of the valves that I use ?

Thanks again for this write-up; it is the only one I have ever found anywhere showing how and what to expect inside these valves.

 

[Bearkiller]

Thanks to this article providing me with the confidence to disassemble and refresh the internals of my two STUCK and FROZEN 4-position WeatherHead 6747 fuel selector valves, I have successfully disassembled and refreshed them back to good working order.

This is what I discovered = Delrin is NOT a good choice for the selector cone in these valves; brass or almost anything would have to be better.

Both my valves were completely froze in position.

Once I got the top cap off and everything except the shaft and Delrin cone set aside, I had to get real forceful with a pair of Peterson Vice Grips locked onto the shaft to get the Delrin to break free of the bore; it was a fight to get both cones out; and, when they did finally pop loose, the way they "popped" I thought they had broken.

I thoroughly polished the bore and the outside of the cone with #000 steel wool and cleaned everything up with brake cleaner.

I slathered Kendall L427 Super Blu inside the bore and outside the Delrin cone.

I packed the blue grease firmly in every empty space within the valve.

Once I had all the parts properly lined up on the shaft, I packed the top cap full of grease as well.

As neither of my valves had ever leaked a single drop, I thoroughly greased the old O-Rings and re-used them.

After all this cleaning and greasing, both valves can be easily turned using my pinkie-finger alone.

The reason for packing everything so full of grease was that I thought maybe it would sort of act as a slow release lubricant as the fuel softened it up and it eventually was all rinsed away.

Thankfully, I had the foresight to install many elbows, nipples, extension couplings, and such; and, I had a JIC adapter and JIC swivel at every one of nine fuel line connections; even at that, laying under the truck and removing all these lines with diesel fuel dripping on my chest ad then having to do the same in reverse to connect everything back up is a complete nightmare I wouldn't want to have every night.

I definitely smell like a diesel mechanic.


Now is where it would be advantageous to tune in and attend:

I decided that, since everything I did was done under that top cap, and that top cap was inaccessible under the floor-board, a quick man like me was smart enough to create a better way.

Before I re-mounted the valves and fuel lines, using the pre-existing stem holes as pilots, I used my bi-metal 1-1/2-inch hole say and made big 1-1/2-inch-plus holes through the floor-board that left room to spare around those top caps.

I already had an Aluminum Plate over the valves that is removable from above the floor, so my new holes are already covered and possums can't crawl through.


As these Delrin Cones are so quick to seize up and freeze up, the next time they do, it won't be such a nightmare to access and service them.


Now, more about the "smooth acting" Delrin:

I have a large collection of brand-new-in-the-box fuel selector valves, all with these Delrin Cones.

Most of these valves are only three-port two-tank valves.

I got them all out last night and tried every last one of them.

Keep in mind that fuel has never been close to these valves; they are brand-new, still in their boxes.

Only one in five of these valves would rotate; the rest were stuck tight with never a drop of fuel touching them.


The reason I got them all out and investigated was that, during all the reading of reviews and such about these valves, there was an inordinate amount of unhappy reviewers stating that they could not rotate their brand-new valves straight out of the box and were quite unhappy about it.


What is it about this Delrin that makes it bond so tight to the brass bore ? ; it is as if they have been Super-Glued in there; you have to get plumb hateful with them to break them loose.

There is very little downward pressure against it at all; a decent ink pen has a stouter spring than is against the cone.

Anderson makes all these valves; surely they know about this.


I have used these valves for years and this has been a problem since day one; even at that, they are far more reliable than any electric fuel switching valve that I have tried; an electric valve will quit working and default to OFF in the most inopportune places with no warning whatsoever; at least these Delrin valves will start tightening up before they seize up.


Now that I have seen what is in there, I think I will have my machinist friend to make some identical cones out of some other material; anything would have to be better than this Delrin mess.


It has just occurred to me that, seeing as my valves are four-port and that fourth port is straight out the bottom, instead of pulling and yanking from above, I could have removed the elbow fittings and used a long punch to tap on the cone from underneath.