RS Disposal

1 hour ago, Joey Mack said:

Yes

thx, I thought so from back when I had to do the head and replace an injector. Sorry about all the questions, but I do appreciate yours and everybody insight

Looks like the leak is actually coming from under the fitting on top of the injector. Does the just screw of and have copper washers for seal?

18 minutes ago, Joey Mack said:

I highly doubt the returns are part of the  issue.. Just messy if they leak.  

I've replaced all fuel lines from tanks to injector pump and still had the issue.  Just replaced lift pump. Haven't had a chance to run trk yet when I spotted the return line leaks

16 minutes ago, Joey Mack said:

I highly doubt the returns are part of the  issue.. Just messy if they leak.  

looks liker they just press on  will any fuel line work?

1979 ENDT 675 engine.  Are the fuel return lines between the injectors anything specific? or can I just use any 1/4inch fuel line? Appears I have one leaking a bit. Could this be part of my fuel problem with the surging and engine occasional miss?

13 minutes ago, Geoff Weeks said:

Good shops are often booked out several weeks and give preference to their local customer base, and bad shops, well why would go there. I can't remember who recommended United, it might have been the truck equipment shop that built the DOT plow trucks (whose name escapes my memory right now). 

I totally understand that and I understand a shop not wanting a truck to take up space trying to source parts. It just would of been nice for someone to at least communicate with me rather than say they will try and then I never hear anything from them.  I understand that lack of communication was from shop management and not the mechanics themselves. When my engine was down I lost about a month waiting to hear from any one of the shops. I was just intimidated by the size of the job I was looking at and unsure about what I was looking at.  Once I got into it it was all pretty much straight forward and didn't have any problems, except time, in sourcing parts. The machine shop I had do my head work also had no problems sourcing what he needed. I was luck on the head being it wasn't cracked.  That one I wasn't able to locate, but once the machine shop informed me the head was magi fluxed (not sure on spelling) wasn't cracked and was rebuildable I stopped looking. I did find a couple of heads but they weren't maxidyne heads and from what I could find wouldn't work.

51 minutes ago, Geoff Weeks said:

And I want you to succeed, which is why I am passing on hard learned experience.

There is tools made to slide the hub, wheels and tires off as a unit. I know one shop that does all brake jobs that way inboard or outboard. He claims it is much faster.

I kinda figured that truck wasn't your sole means of employment, but you never said, and I didn't assume.

There was a shop I used in the valley (if we are talking the SLC valley) that had no problem working on old stuff when I was out there. No idea if they are still in business. I'll see if I can find their name and number. I know they did a pinion seal that was on my '83 was gushing, and I wasn't going to drive it home over 1000 miles like that.  

United Diesel Service 1905 pioneer. Did fair work, I used them a coupla times, but that was a decade ago so things might have changed.

They were one of the many I contacted about the engine work. Talked with about a dozen shops big and small. They said they would get back to me as far as sourcing parts etc. All me if they could find parts they were 6 to 8 weeks out.  Never did get a call back from anybody I talked with.  All shops I talked with even on the brake job as at least 4 weeks out.  If it's a job I can do I'm not waiting that long for something I can do in a day. I have no problem getting my hands greasy.  I just get the impression from the shops I talk to they have no interest in working on a 40+ yr old truck.  As far as the brake job I did pick up a dollie from Harbor freight and modified to to support the hub with the inner wheel still on and once I had it so that it would slide on and off straight the job was basically a piece of cake.  The only delay was I had to have the shoes relined being new shoes weren't available locally, but that only took a day. Not too many parts for my truck are available locally and unless it is just a generic parts that doesn't require a VIN number to look up, I have to go to the dealer because everybody tells me that my VIN number isn't a good number.  My older parts guy, been with Mack for 30+ yrs, there has no problem.  The newer guys need to be shown how to look up my VIN.

I do appreciate all you are passing on to me and I'm not too proud to not accept criticism and or suggestions/insight 

52 minutes ago, Joey Mack said:

Just keep doing what youre doing. Good mechanics are scarce..

that I am finding out

10 hours ago, Geoff Weeks said:

BTW, unless that pinion seal is gushing oil, I'd put my efforts elsewhere before dealing with a "wet" seal. From what I saw of the airlines on the drier, that is much more likely to either get you shut down by DOT or leave you stranded. 

A damp or wet pinion seal that is not soaking the brakes with oil might get a mention on a inspection report but will not leave you stranded. You can check the oil and top off as needed, but a bust air hose leaves you dead in the water.

Also, how did you make out with the fueling issue? was that fixed when you replaced the hose, or are you still running the electric pump?

My truck deals with alot of snow and wet salty road slush that get frozen and packed into the frame rails and everywhere underneath.  Current have 1800 lbs of that according to the scale house at the dump.  It took me a day with a torpedo heater to get the fuel line to where I could get it out.  The fuel problem is still there so I have ordered a new lift pump and just replumbed the electric back in. 

The same issue is going to be changing out the air line from pump. In looking closer at the dryer and am pretty sure it is going to be junk from the corrosion from all  the road salt.  Going to pick up another one before I have the air lines made in case I need to route the lines differently.

After cleaning the frozen slush out from around the rear of truck I noticed that the pinion is leaking pretty bad.  Brake cans have oil on them.  In checking oil level it is lower than I would of liked to of seen it. Finger crossed I didn't mess up anything inside the differential.  Good time to do another gear oil change also.

My truck only runs about 150 miles a week with 2 trips across the valley of about 45 miles round trip.

1 hour ago, mowerman said:

You know if it’s a working truck just chalk  it up to business expense I believe that’s what he was asking in the first place can I do this myself?

It is  a working truck and I have bought numerous tools that have been needed to do the work.

8 minutes ago, Joey Mack said:

How about a picture of the input shaft and the seal housing. I bet this is easy..  back then Synthetic was not used. Seems to me there was a 90 W mineral based oil.  I bet 80W90 oil would be just fine.  I also bet the seal can be popped out if it has a flange, or removed by puttin a sharp screw into the metal part of the seal and using a claw hammer or the like to pull the seal. Are you familiar with that method ? 

not with the truck right now for a pic. I am familiar with that method of removing the seal. Just trying to get all my ducks in a row for when I do this job being when I have the truck at the shop I don't have my personal vehicle available whereas truck is staged at a different location for work

7 minutes ago, mowerman said:

im just a do it yourselfer cant help,,,im sure someone will chime in good luck,,bob

I am more of a light truck/automotive mechanic. Getting my feet wet with heavy truck maintenance and repair

Under  truck greasing what needs done I noticed that my pinion seal is wet.  Question is is replacing the seal pretty much straight forward as in with light trucks? Anything I should be aware of being I have never done a heavy truck pinion seal? 1979 Mack and I do believe it is the single reduction differential. Pretty sure I don't have a socket big enough so, off hand does anybody know the size needed I would need to purchase? Per factory shop manual looks like nut torque is 600-900 ft lbs.  Only reference to gear oil is "GO-F-90". An online search for that number shows it being 75W-90. Is this correct?

1 hour ago, Geoff Weeks said:

Yes, the fittings are, I can tell by the type of end, they are not crimped on.  Pull the hose, tighten on to a fitting, to hold the inner portion, unscrew the hose end from the part attached to the  fitting ( this will be normal right hand thread). then unscrew the hose from the metal end (this will be left hand thread).  If you still have trouble understanding what I am saying, and I agree it is hard to convey in words, I can see if I can find some fittings like yours and take a picture with them apart to show what I mean. Non reuseable will be crimped on where the hose jacket goes into the fitting. 

I suspect your air system problems stem from excessive compressor cycling, and/or a defective drier. With a good drier and air system, temps well below zero are not a problem. 

I have used reusable fitting so I do understand what you are saying.  I will look closer

2 minutes ago, Geoff Weeks said:

Looking at your air drier, it looks like all the hoses are using re-usable fittings. You could buy 25' or so of the different sizes to keep at the shop and a few mating fittings (to take the re-useable ends off the hose). That and a cut off wheel for a saw or die grinder and you an make up new hoses when stores are closed. Wheel seals, brake shoes are good to have on hand. 

Things like brakes, king-pins, tie rod ends etc can be monitored and planned for when they wear out.

What would you do if a brake treadle valve failed? A rear axle?

Do you keep a spare alternator on hand? if not what is your plan if one goes bad on a Friday night?

I am not picking on you, I am explaining what things you need to have a plan for when operating a single truck with no down time.

A truck with a manual transmission can be roll started if it has air to release the brakes, but an auto, you might want a starter on hand. 

 

I keep brake shoes, wheel seals, alternator, starter, most air valves that are on the truck (seems I have alot of trouble with those in a really cold winter whereas the truck is stage up canyon and can see single digit or lower temps on a consistent basis). Just recently did a total rebuild of front suspension all the way from springs, steering components, brakes and wheel seals.  So I think those are good for a bit but as you say will definitely be monitored on an on going basis

The fittings on the air dryer are no reusable ones unfortunately.  But I have kicked the idea around of buying bulk hose and getting reusable fittings.

I don't feel that you are picking on me. I value all of your thoughts and insight being I know what I don't know. If I thought I knew it all I wouldn't be asking questions. I appreciate anything and all you have to say  Thank you

38 minutes ago, Geoff Weeks said:

Well it does seam to confirm that the suction line is the problem. It isn't a long time cure to a hose that is coming apart. I don't understand how you had the time to rig this up but don't have the time to replace the hose? 

I have been in your shoes running a single truck and trying to keep it running and my customers happy.

Am I to take it, by your statement that this was "the last hose" to be replaced, that you have addressed the other air lines?  I doubt it is the "last hose" as there are so many on a truck. Did changing out the air hoses solve your drier problem?

 I started stockpiling hose and fittings at my shop. I also got a parts truck that I could rob parts off of, either to use or to send off as cores for rebuild while my money make was still running. I am thinking things like a P/S box that required to be re machined for a seal to hold. 

If you are going to run a single truck, you HAVE to be proactive with maintenance. The guy that picks up garbage, showed up in a different truck one day, I asked if he bought a new one, he said no, it was a rental while his was in the shop. I didn't know you could rent them, but I guess around here you can. Another possibility is if you know a "competitor" who will not "stab you in the back" that could cover a pick-up for you while you do a repair. I know, this takes a lot of trust, but there are people who will help out as long as you will when they need it.

 

Running an old truck as a single operator is difficult, Often it can mean being one big breakdown from loosing it all. that is why it is so important not to have multiple small breakdowns that could be prevented. Most customers will understand that everything breaks at some point. As long as it isn't common, they will live with a temp interruption in service.

I carried brake diaphragms, various hoses, filters, throttle return springs, etc so most minor failures could be repaired right where and when they happened.

Many small business fail when they failed to plan on a breakdown. A parts truck can be a true windfall of parts if you have room to store one.     

Not replacing the fuel line wasn't a matter of time, It was a matter of availability of being able to have one made over the weekend.  It was the last FUEL line needing to be replaced. The inline pump isn't meant to be a long term cure.  It is just another step in my trouble shooting process. Being the line wasn't wet anywhere along it's length with pressure on it makes me think that it wasn't sucking air. Being any older truck alot of parts aren't able to be locally sourced. I do have a new lift pump on order.  My mindset is one that I need to know what was actually causing the problem and not just throw alot of parts/repairs at it in hopes that one of them fixes the problem.  Time consuming and can be frustrating I know, but just the way my mind works.

I haven't really addressed the air lines yet being the truck has no problem building air. I was just concerned about servicing the dryer.  Once I get to the dryer job the lines from the compressor to dryer and from dryer to wet tank will be replaced alone with the signal, etc lines to and from governor.  The truck is a 1979 and when my dad was running it I don't think it was maintained very well knowing that the arrangement he had with his brother (who owned a ski lodge in the resort) that every 4 or 5 yrs the truck is replaced.  The truck have never run full time even back then.  The truck then sat for 20+ yrs before I put it back to work  Mile wise it only has 160,000 miles, but it it 47 yrs old so just is not really wearing out, it is aging out.  My biggest problem has been sourcing parts as I found out with the engine breakdown 2 yrs ago. The truck only really makes any money thru the ski season (about 4 or 5 months) and then it only works two days a week for about 10 hours total, so there is not alot left over to stock pile anything more than than maintenance parts and smaller breakdowns.. I do totally understand what you are saying about a parts truck, but that search didn't go well back when I had my engine breakdown

On 1/18/2026 at 9:52 AM, Geoff Weeks said:

I had my truck have somewhat similar problem. It was the suction line from the tank to the pump. On hard pull it would draw in enough air to cause a problem, lighter work, it would tolerate the little air just fine. A new hose and the problem was fixed. 

Just something that is easy enough to try, and given the state of the other hoses on the truck, I would say is a good bet. Stratoflex etc hoses don't last forever.

Being that the tank to primary filter hose is the last one needing replaced I decided to try a wild hair idea.  I spliced in an inline fuel pump (being the line was going to be replaced anyway so no concerns about cutting it) and powered it off a keyed accessory circuit. Powered it on and had about 20 psi at the injector pump. Started the truck and let it run for a bit watchin the fuel gauge to see if having the lift pump still in line (if indeed the pump is bad) would have any adverse effect on the fuel pressure.  Being it was a work day I had to climb canyon I decided WTH and give it a try being after about 15 minutes of fast idle the pressure seemed to stay about the same.  Climbed the canyon with no problems at all.  I do believe I felt there was a bit more power available, I did notice that the boost pressure was a little higher and the the pyrometer was a little higher (neither was crazy high). Correct me if I am wrong, but my thinking those factors would mean the engine was getting better fuel flow.

On 1/18/2026 at 4:50 PM, Geoff Weeks said:

Just a warning, mine went from just a little problem to not being able to pull a load in less than a day. One of the 2 times in my whole time owning trucks, that mine was on "the hook".  The other was when the fuel pump "self destructed" Running just fine one moment, and dead the next. 

Got to go, can mean not making it plus a tow bill. Better to delay a partial day to address the problem, then loose 2 days when it shuts down and has to be towed in. Just a little hard won experience. Not only do you have the repair bill but you have the tow bill as well. 

I totally understand your comment.  My problem about truck not running is it is a garbage truck and I service a ski resort town which in the ski season is extremely busy particularly on holidays.  non of my accounts have the space to miss a pickup day which is 4 or 5 times a week.

5 hours ago, Geoff Weeks said:

I had my truck have somewhat similar problem. It was the suction line from the tank to the pump. On hard pull it would draw in enough air to cause a problem, lighter work, it would tolerate the little air just fine. A new hose and the problem was fixed. 

Just something that is easy enough to try, and given the state of the other hoses on the truck, I would say is a good bet. Stratoflex etc hoses don't last forever.

thats the last hose i have to replace. Would of done this weekend but my hose place is closed on weekends and truck has to go to work tonite. It's hard to work on equipment that also has to work every day. 

14 minutes ago, fjh said:

Have you checked the tank vent?  And You can actually take the Drainback tee apart and stretch the spring to raise the pressure some 20 25 psi won't  hurt anything!  

haven't actually checked the vent it self, but I did try running with the fuel cap loose. I will try the drain back tee and see if it makes any difference. Being a one man show with only one truck and this being my busy season and truck having to also work while I try to figure this out makes for some long frustrating days

2 hours ago, Freightrain said:

15# is about right.

I was having power issues years back and found my lift pump was failing.  I mounted a fuel pressure gauge out on the air cleaner so I could watch it while driving.  It would rise and fall.  Replaced pump and was a solid 15#.  

If you don't have a liquid filled gauge it will flutter due to check valves in the pump.  A liquid filled gauge will dampen the bouncing needle some.

The lift pump is where the plastic check valves are at that was mentioned to check by Terry.

truck seems to run fine around town but when I am climbing the canyon occasionally it will start to miss (more than just loosing power) and I would have to pull over and let it idle for a bit.  Then I could start back up again.  I do understand about a liquid filled gauge, but would think the gauge attached after the secondary filter would mellow the fluttering a bit.  I did notice a couple of times that the gauge did drop to zero for several seconds.  I did pull the plastic check valves and they did look ok, but don't have new to compare against.  Truck only has about 160,000 road miles (not sure about motor miles being there is a pto running a packer) but then again it is 47 yrs old and sat for about 20 yrs before being put back into service about 8 yrs ago.  Truck only really works part time anyway, but I do know stuff breakdown with age alone

9 minutes ago, terry said:

Not sure on the fuel pressure, maybe someone else will chime in on that.  terry

from what I have found its about 15 psi.  My question was the fast fluttering

8 hours ago, fjh said:

Also check  the return check Tee there if you take it apart to see if the spring is broken that can cause low pump pressure !  you need bare min 15 psi to run clean at full load fuel demand !

pulled the return tee of and took apart.  everything looks good there. Haven't pulled the cap screws yet.  Put a fuel pressure gauge on the injector in line and at idle the needle fluctuates between 10 and 30 psi. Doesn't change much if I go to a fast idle.  Should this reading be more smooth rather than fluttering?  Would this be sign of a bad fuel pump?

I did pull the caps and the springs appear ok and the plastic check valves are ok