Oil pressure problem w/ b6100

[morson82]

Ok, I have read the other threads about this issue, but I have some other issues going on as well and want to get some feedback......So here it goes:

I bought a used and abused B6100 this past summer and have been slowly rebuilding and repairing it. It came with a B219 FEL and a B670 Backhoe. To date I have replaced all the hydraulic lines, cylinder pins, rebuilt all the cylinders and controls, new tires, oil and filters, tranny flush, new headlights and flashers and a new low oil pressure warning light harness, just to name a thing or two.

Just this past weekend I was able to get the FEL all back together and test her out in the garage. No problems, ran the tractor at idle and max rpms and everywhere in between getting all the air out of the lines and testing the FEL; not once did the oil pressure light come on.

Yesterday I finished getting the backhoe all back together and tested her out as well. Again, I ran the tractor at all throttle positions while removing the air from the hydraulics. I then noticed that the red oil light was on. I shut her down right away and after checked the oil level in the engine, she was full. I started her back up and the light was off. I gave her lots of throttle and the light stayed off. I then engaged the stabilizers and swing arms of the BH and still no light. It wasn't until I engaged the boom portion of the BH that the light came on. I then tried to lower the rpms and increase the rpms but the light stayed on.

I shut her down and restarted and let the engine run for several minutes, both at high and low rpms, and the light did not come on. Again, as soon as I engaged the boom the light came on.

I removed the oil pressure sending unit (it looks to be the original) and sort of cleaned it up and reinstalled it "finger tight". I then ran the tractor through the same scenerios and the light never came on, even with the boom engaged (and yes, the wire was attached). Thinking that that was all it was, I tightened up the sending unit and as you guessed, the freakin light came on.

I am buying a pressure gauge and am going to check that, but just wanted to pick everyones minds.......definitly hoping this isnt a tear down!

 

[Kytim]

Your on the right troubleshooting tract. An actual PSI# means everything an these idiot lights are just that. When you have solid numbers let us know back and we'll go from there. Oh those threads are most likely metric in the block as well. Sometimes those adapters are harder to find. If you elect to use a SAE threaded adapter use tef tape and only install far enough to seal. 1 to 1 1/2 turns. Your not looking to make it perment just testing. Those senders do fail and give false reading from time to time.

 

[Stumpy]

I'd first check if it's just an electrical issue which you can diagnose easily once you get a gauge on the sender port.

If the light is reading correctly then oil starvation is the issue. The cause is harder to discern.

One possibility is the oil is overfull and at higher rpms the counter weights and big ends are frothing the oil so the oil pump can't pick it up.

Another is there is sludge somewhere in the oil galleries or pump gumming up the works. The relief valve may be stuck open or the passage to the sender is plugged in which case you've got much bigger problems.

I'll leave it at that until we get more information.

By the way the thread is probably 1/8th BSPT which is close enough that 1/8th NPT will thread in but it won't seal and will probably damage the threads. Identify what you've got there. A .405in OD on the external thread (sender) and 27 threads per in means it's 1/8th NPT. Same thing but 28TPI and you've got British Standard Pipe Thread. Anything else and it's probably metric.

 

[CAE]

morson82,

I just put an oil pressure gauge on my B7100 for the same reason, my light would flicker now and then. Like you my tractor was abused badly, to put it nicely I haven't found one thing that didn't need some TLC, I'm sure of more to come.
Anyway I greased up a 1/8" npt pipe tap and ran it in the hole for the sending unit stopping 7 turns from the end of the tap, I have tapped a few holes in the last 49 years in my trade.
I then used my shop vac and sucked out what chips were left, put a little PFT paste on the fitting for the oil pressure gauge tightned up the fitting and ran the lines to the gauge. The pitch on the sending unit and the pipe tap are very very close, not much material was removed by the tap.
I got 35 psi @ idle and 45 psi above idle, I was stoked the sending unit was bad, hope that this is true for you. I like having a gauge and no leaks.

CAE

 

[CAE]

When I removed the sending unit it snapped off leaving the remainder in the hole, it had been overtightened and was streched, I used an easy out to get the broken part out of the block.
I took what I had to work and put it on our optical comparator, it was close to 27 tpi.
Stumpy is right about verifying what pitch your tractor has, I felt comfortable
that the piece that came out of the block was 1/8" npt.
CAE

 

[morson82]

Thanks for all the input. As soon as I get the gauges and numbers I'll post the results.

 

[morson82]

ran the tractor today and I noticed what seems to be an excessive about of smoke coming the breather pipe.....What is the norm and if it is excessive, what is the cause?

 

[bruceatlam]

You're not supposed to have any "blow-by" --- i.e. smoke out of the breather tube. But, first, make sure the engine is up to temp before you "evaluate" your blow-by. Blow-by happens as a result of pressure escaping the cylinder when the cylinder fires. The pressure is supposed to stay above the piston and push it down, but worn rings can let the pressure into the crankcase where it pressurizes the crankcase. The pressure in the crankcase escapes by traveling up the oil return passages into the space under the valve cover. That pressure then escapes out the vent tube. The "smoke" is oil vapor.

I think that everyone has a little blow-by --- most can't see it. A lot isn't doing you any good but probably isn't immediately fatal. The compression loss will result in less performance --- maybe hard starting. You'll get more soot build up in your oil at a faster rate --- more long term bearing wear.

There's nothing good about excessive blow-by -----------

 

[morson82]

This is really starting to sound like a complete engine rebuild.......I can just hear my wife now................

 

[Stumpy]

I'm not sure you've got a problem. Several older tractor diesel's I've seen will blow white smoke out of their draft tubes when cold. Diesels always have quite a bit of blow by, ever wonder what turns your oil instantly black? Also the rings and cylinder walls aren't up to temperature yet and not sealing well. You can check the compression to be sure but I'd concentrate on your oil pressure light problem first.

 

[Kytim]

I'm with stumpy on this one. I really don't think you've got a problem. Regular maint. maybe but not a serious problem. As a matter of fact kind sounds just like one of mine.

 

[morson82]

Well, a ray of hope in an otherwise dark and cloudy sky.....haha. I got my new pressure test kit, which comes with metric adapters. I'll post my result later.

Oh, and to add insult to injury, I was removing the seat bracket ( the one that goes with the backhoe attachement) and I snapped off a bolt in the top of the case area, the cap assembly I believe that goes to the three point lift.........I dont have an acetalyene torch set either. Its sticking out about 5/8 of an inch and I have tried but cant get it to budge. I really dont want to drill it out for fear of screwing up housing......Might have to trailer it to someone that has a torch set.

 

[morson82]

Alright, put the pressure gauge on and fired her up.

Reading at initial start: 60psi
Reading after about a minute of running: 50psi
Reading at idle: 50psi
reading at max: 60psi

Looks like I have a bad sending unit......yes?

What are the general pressure supposed to be?

 

[Stumpy]

That sounds good to me. I'd drive her around for 20 minutes to warm the oil up and then check again but that's a good sign. Should be around 30-40 at idle with hot oil.

As for the bolt soak it in penetrating oil til you get it to someone with a torch.

 

[B7100]

Well, a ray of hope in an otherwise dark and cloudy sky.....haha. I got my new pressure test kit, which comes with metric adapters. I'll post my result later.

Oh, and to add insult to injury, I was removing the seat bracket ( the one that goes with the backhoe attachement) and I snapped off a bolt in the top of the case area, the cap assembly I believe that goes to the three point lift.........I dont have an acetalyene torch set either. Its sticking out about 5/8 of an inch and I have tried but cant get it to budge. I really dont want to drill it out for fear of screwing up housing......Might have to trailer it to someone that has a torch set.

I use a twin carbon torch on my stick welder to heat things up,they seem to have gone out of fashion these days but they are a usefully piece of kit if you don't want to hire gas bottles for the odd times heat is needed.
If you have a stick welder but no torch then studs can also be removed by pushing a larger size nut over the broken stud, then keep firing weld onto it until its glowing realy bright which forms a new head .when it cools to just a faint glow,gradually apply torque back and forth with a light feel to see if its freed off.
Dave

 

[bruceatlam]

Alright, put the pressure gauge on and fired her up.

Reading at initial start: 60psi
Reading after about a minute of running: 50psi
Reading at idle: 50psi
reading at max: 60psi

Looks like I have a bad sending unit......yes?

What are the general pressure supposed to be?

I run 30 psi at idle and 40 psi at 2,600 rpm when fully heated up ---- that's after working hard for 30 minutes.

 

[Kytim]

Put a $15 sender in it if you want the light to work again or put a permanent gauge on it and your done.

 

[morson82]

So, I ran the tractor today with the pressure gauge attached about a mile down the road and she did great, nothing less than 45-50 psi at idle and 60-65 at max! Its about time I caught a break on this thing!!!

I was able to get that broken bolt by heating and cooling it with a torch....took 2 hours but I got that @#$% out.

I fabed out some new pins for the seat, painted everthing and put the complete swivel bracket and new seat on; and I dont mind saying she looks great!

Now I found that several of my freeze plugs are leaking......&@%*$*&#$!!!!
Have a new set on its way and will replace them all.....

Here are a few pics as she sits today...

 

[Lil Foot]

Glenn, it looks great! I wish mine was that pretty! Love the new seat, tires, & paint! I have my backhoe all done & have the tractor here at the house, but a neighbor wants me to do some box blade work on Tuesday, so I'll have to wait till later in the week to mount the hoe.

Is that your only bucket, and are there removable teeth on it? It looks like just the stubs.... no teeth caps.....

Looks like a great shop/garage, too. Whats the car in the background?

 

[morson82]

Hi Bill, thanks for compliment. As you are well aware, it's a lot of work.

As for the bucket, I really haven't tried to see if they are teeth or the teeth anchors. I really wish I could find a narrower bucket, say 10-12 inches; basically a trenching bucket.

As for the car, that's Mary, my 1942 Dodge D-22. I am completely restoring her to her original glory. Pretty rare car, as she was built in Nov 1941, just before Pearl Harbor. All manufacturing of cars stopped in Feb 1942 for the war effort. She was pretty loaded for a car from 1942. Her assessories include, and these are factory:
- electric 2 speed wipers
- reverse light
- turn signals
- defrosters w/ variable heat controls
- clock
- radio
- and a Fluide Drive tranny (semi auto)

I'm almost positive that I'm the only person in CT that owns one of these. I haven been to 100s of car shows all over New England and have never seen one. I will post a few pics of her before I started the resto later.