Guys, does anyone have the engine oil pressure specs for a B7100. What are the specs at idle and open throttle? Also, what should the running temperature of the engine be? And where is the best place to measure it from? My tractor is a 1982 B7100 4x4 HST. Thanks
B7100 oil pressure specs
- Thread starter KevinD
- Start date
My I&T Shop Manual specs 28-64PSI unrestricted which I assume means before the filter. Plus dash gauges aren't known for being terribly accurate.
This is a thermosiphon cooling system meaning there's no water pump or thermostat and it just circulates on convection due to the temperature drop across the radiator. This means your running temperature will be somewhat variable. That said the usual target water temp is about 170-180F and you don't want to get much over 220F. I'm not sure what temp the radiator cap will start releasing and the whistle blowing. Best place to measure is the hottest part which is the head. If you're installing a temp gauge it needs to be in the flow and most people have used the upper water neck plate on the head. Anywhere in the upper radiator hose would work too if you had an splice fitting.
This is a thermosiphon cooling system meaning there's no water pump or thermostat and it just circulates on convection due to the temperature drop across the radiator. This means your running temperature will be somewhat variable. That said the usual target water temp is about 170-180F and you don't want to get much over 220F. I'm not sure what temp the radiator cap will start releasing and the whistle blowing. Best place to measure is the hottest part which is the head. If you're installing a temp gauge it needs to be in the flow and most people have used the upper water neck plate on the head. Anywhere in the upper radiator hose would work too if you had an splice fitting.
Thanks for the help. Trying to figure out what's up with my tractor an wanted to start with some specs as a base line. Oil light comes on after about 1 hour, flickers at open throttle and is fully on at idle. Also, I get some coolant drip out of the overflow after the first 15 minutes or so of use then it subsides.
Yeah get a gauge on that and see what's up. You're probably just barely getting enough pressure to shut the light off cold and once it's warm it drops off. Any coolant in the oil? Could be a few things none of them good. Easiest thing to check is the pressure regulator and bypass valve, should be two bolts on the filter housing.
Thanks Stumpy, no oil in the coolant. The tractor does not appear to be overheating, hoping the coolant situation is simply a bad seal on the radiator cap.
I made a list of things to check/replace with respect to the oil pressure situation:
1. oil pressure sensor
2. oil filter and oil change (was done recently so I doubt this is the cause, and replaced the filter 2x thinking it may have been a bad filter)
3. oil presure relief valve assembly(located below the spin on oil filter). Is there a way to check this? I ordered a new one for $20 so if it is easy to replace I may just try it. Is it easy?
4. you mentioned a bypass valve. What's this? Are you referring to the valve inside the oil filter or is it something else?
5. check to see if the plugs in the end of the camshaft fell out. Looks like the timing chain cover would need to come off. Is this a big job?
6. Any other possible causes other than a worn out engine? The problem seemed to start sunddenly so I'm hoping it's not the worse case scenario.
Thanks
I made a list of things to check/replace with respect to the oil pressure situation:
1. oil pressure sensor
2. oil filter and oil change (was done recently so I doubt this is the cause, and replaced the filter 2x thinking it may have been a bad filter)
3. oil presure relief valve assembly(located below the spin on oil filter). Is there a way to check this? I ordered a new one for $20 so if it is easy to replace I may just try it. Is it easy?
4. you mentioned a bypass valve. What's this? Are you referring to the valve inside the oil filter or is it something else?
5. check to see if the plugs in the end of the camshaft fell out. Looks like the timing chain cover would need to come off. Is this a big job?
6. Any other possible causes other than a worn out engine? The problem seemed to start sunddenly so I'm hoping it's not the worse case scenario.
Thanks
It appears I was mistaken, the only part I could find externally on your machine is the relieve valve (aka the regulator) beneath the oil filter. It provides an upper limit to the oil pressure. The bypass valve allows oil to flow around the filter if the pressure rises too high to prevent oil starvation in case the filter gets plugged. Your's is probably internal to the filter. I'd just inspect the relief valve and check for anything obviously broken and make sure it's not clogged with sludge.
I'd get a gauge on it and confirm whether it's actually an oil pressure problem and go from there. There's a plug in either end of the valve cam shaft to allow the cam to hold oil pressure and it's not unheard of for them to pop out. That's a possibility along with a worn out motor or oil pump problem.
I'd get a gauge on it and confirm whether it's actually an oil pressure problem and go from there. There's a plug in either end of the valve cam shaft to allow the cam to hold oil pressure and it's not unheard of for them to pop out. That's a possibility along with a worn out motor or oil pump problem.
Re: B7100 oil pressure problem and specs
Update on the low oil pressure problem:
I put the test gauge on the machine. At cold start up, the pressure read 52psi at high idle. I'm currently using 15w-40 oil. I cut the lawn using the 60" belly mower, ambient temp was 60F. Within the first 10-15 minutes, the oil pressure started to drop. Within 45-60 minutes the pressure dropped from 52psi down to 15psi at which time I shut the machine off. I let the machine cool for 4 hours at which time I replaced the oil filter(again) and checked the oil level which oddly read a high. Note, about 1 1/2 years ago I replaced the hydraulic pump because it was leaking hydraulic oil into the crankcase. I was surprised to see the oil level high by about 1 quart because when I changed the oil I used the exact prescribed amount. I drained the excess oil and started the tractor. Same situation, started at 50+psi and dropped to 15-20 psi after about an hour of mowing. Question, do you thing the hydraulice pump failure and the oil it dumped into the crankcase could have caused any damage. To the best og my knowledge, the tractor was run for maybe 5 hours with the hydraulic oil in the crankcase.
Nest steps: I plan to replace the relief valve assembly located below the oil filter housing. Does anyone have any tips on accessing this part. Looks like it's hidden behind the frame rail. I think I've read that some guys drill a hole in the frame rail to access. Is this the best method? If so, does anyone have the measurements for hole placement?
What else: If the relief valve does not fixt it, I plan to check the plug in the camshaft. Any tips or suggestions for this task? Is there anything else I should check at this point?
Thanks for the help!
Update on the low oil pressure problem:
I put the test gauge on the machine. At cold start up, the pressure read 52psi at high idle. I'm currently using 15w-40 oil. I cut the lawn using the 60" belly mower, ambient temp was 60F. Within the first 10-15 minutes, the oil pressure started to drop. Within 45-60 minutes the pressure dropped from 52psi down to 15psi at which time I shut the machine off. I let the machine cool for 4 hours at which time I replaced the oil filter(again) and checked the oil level which oddly read a high. Note, about 1 1/2 years ago I replaced the hydraulic pump because it was leaking hydraulic oil into the crankcase. I was surprised to see the oil level high by about 1 quart because when I changed the oil I used the exact prescribed amount. I drained the excess oil and started the tractor. Same situation, started at 50+psi and dropped to 15-20 psi after about an hour of mowing. Question, do you thing the hydraulice pump failure and the oil it dumped into the crankcase could have caused any damage. To the best og my knowledge, the tractor was run for maybe 5 hours with the hydraulic oil in the crankcase.
Nest steps: I plan to replace the relief valve assembly located below the oil filter housing. Does anyone have any tips on accessing this part. Looks like it's hidden behind the frame rail. I think I've read that some guys drill a hole in the frame rail to access. Is this the best method? If so, does anyone have the measurements for hole placement?
What else: If the relief valve does not fixt it, I plan to check the plug in the camshaft. Any tips or suggestions for this task? Is there anything else I should check at this point?
Thanks for the help!
Re: B7100 oil pressure problem and specs
I really don't think that the relief is a problem --- if I were you, I would go to the next step -----.
When you remove the front case cover to check the camshaft plug (if it has one), you can then check the oil pump at the same time. If you don't find the problem there, you most likely have bearing issues.
Your low oil light comes on at 7 psi ----
I really don't think that the relief is a problem --- if I were you, I would go to the next step -----.
When you remove the front case cover to check the camshaft plug (if it has one), you can then check the oil pump at the same time. If you don't find the problem there, you most likely have bearing issues.
Your low oil light comes on at 7 psi ----
Big Kahuna
Member
Equipment
Kubota 2000 L3010 HST with Loader ,1992 B7100HST , 1979 B6100E & 2007 F2880
My B6100 did the same thing about 3 years ago, everybody had me in a panic that it was the plug on the end of the cam, it was not. I checked oil pressure at the sending units location and it read 50 lbs cold 1/2 throttle,let it run for 30 minutes and down to an idle it read 12 lbs, replaced the sending unit and light works like it should, as for the anti-freeze.........well everytime I mow it spits some anti-freeze out the overflow, and that's been for 33 years, so I think that's okay to do that, weather and temp mean alot!
Big Kahuna
Big Kahuna
Re: B7100 oil pressure problem and specs
Engine oil warm at idle (800rpm) should be 10psi or higher
Engine oil warm at rated speed (some say 2800rpm others say 3200rpm) should be 29psi or higher
Oil pressure will drop as the oil warms up but once warm, you need to meet the minimums I posted above.
If your warm oil pressure is 15-20psi but the rpm is only 1800 to 2000rpm then I would guess you are fine.
What rpm are you at when you are checking the oil pressure?
Engine oil warm at idle (800rpm) should be 10psi or higher
Engine oil warm at rated speed (some say 2800rpm others say 3200rpm) should be 29psi or higher
Oil pressure will drop as the oil warms up but once warm, you need to meet the minimums I posted above.
If your warm oil pressure is 15-20psi but the rpm is only 1800 to 2000rpm then I would guess you are fine.
The fuel lift pump can blow a hole in its' diaphragm and pump fuel into the crankcase. This might explain the rising oil level and the falling oil pressure.
I do not have a RPM gauge but I would guess my engine speed while mowing is approximately 2000 rpm, maybe a little higher. If you have the same tractor, the trottle position is right at the seam between the hood and the dash panel. I understand oil pressure will drop as the oil warms but I'm concerned that the oil pressure goes from 50psi to 15psi in less than an hour. That seems excessive to me.
Birddogger mentioned it might be the fuel lift pump leaking if my problem with a over filled crankcase continues. Has anyone else ever encountered this problem? Can anyone tell me the steps needed to check this diaphram? Also can anyone provide me with the steps to replace the pressure releig valve and also check/replace the plug in the camshaft? On the pressure relief valve, I need to drill a hole in the frame to access, right? Does anyone have the measurements on where the hole is drilled? Thanks for the help. I hope it's one of these items and not a worn out engine!
If the camshaft plug was out you wouldn't get above 10 or so psi ever.
If the pump is discharging into the crankcase the first sign would be the hot oil smells strongly of diesel fuel. Otherwise you could remove the pump and seal the outlet tube, apply a small pressure (< 10 psi) to the inlet tube and see if you can see bubbles of fuel out the flange side, or even hear it hiss as air bleeds out the suspected hole.
If the pump is discharging into the crankcase the first sign would be the hot oil smells strongly of diesel fuel. Otherwise you could remove the pump and seal the outlet tube, apply a small pressure (< 10 psi) to the inlet tube and see if you can see bubbles of fuel out the flange side, or even hear it hiss as air bleeds out the suspected hole.
from thread http://www.orangetractortalks.com/forums/showthread.php?t=7705
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