Oil & Fuel Why does oil light come on?

[bky]

I have a question about my l245dt with 1445 hours. My oil light comes on after the tractor is running for a few minutes , and if i rev the rpm's to 15oo rpm the light goes out. I try not run it over 2000 rpm's
I started a couple weeks ago and since then i did change the oil and have since checked the level and it is OK. i am wondering if the oil pump is going out? if so what would it take to change it.

 

[KennyV]

To find out what is really going on... you need to remove the oil light sender, (Switch). And screw in an actual pressure gauge... Then you will be able to see what the real oil pressure is at start up & what happens to it as things warm up... KennyV

 

[rbargeron]

Replacing the oil pump is a lot of wrenching (major disassembly) so it would be a good first step to connect an actual pressure gauge so you can watch what's really going on. The sender switch can be replaced with a capillary tube and gauge from an auto parts store. Once you have a way to watch how pressure varies with conditions you'll know better how to proceed. At low rpm and load, even 5 psi is enough to oil the engine. You might get lucky and find it's just the sender spring that's gotten weaker with age. Good luck.

 

[crazyal]

It could be several things. My suggestion would be to buy a simple oil pressure gauge and verify that the pressure is low. If it is low I'm not sure if simply replacing your oil pump is going to solve your problem.

It could be something like your rod and camshaft bearings are worn and more oil is flowing by them as your engine runs. As you increase the RPMs you increase the flow but since the gap between the parts doesn't increase the extra flow means increased pressure.

 

[Gunny]

I'd check actual pressure as suggested above, if it falls just below minimums, you might try a little heavier weight oil.

 

[varmint]

Not long after I got my used B8200, there was a thread on triple gauge sets that some TBNers were talking about. I invested $13 in a set- oil pressure, voltage and coolant temp. I made a "console" to mount them, but installing them was easy. I just installed a tee were the oil sender switch was, and bingo- very useful, I think. Seems to me everyone should have such information about how their engines are working.

 

[moored4]

Not long after I got my used B8200, there was a thread on triple gauge sets that some TBNers were talking about. I invested $13 in a set- oil pressure, voltage and coolant temp. I made a "console" to mount them, but installing them was easy. I just installed a tee were the oil sender switch was, and bingo- very useful, I think. Seems to me everyone should have such information about how their engines are working.

That's a nice looking install! :thumbsup:

 

[bky]

Replacing the oil pump is a lot of wrenching (major disassembly) so it would be a good first step to connect an actual pressure gauge so you can watch what's really going on. The sender switch can be replaced with a capillary tube and gauge from an auto parts store. Once you have a way to watch how pressure varies with conditions you'll know better how to proceed. At low rpm and load, even 5 psi is enough to oil the engine. You might get lucky and find it's just the sender spring that's gotten weaker with age. Good luck.

Any idea of what size thread i would need? also is it called a capillary tube gauge?
or could I use a standard gauge. Pressure Gauge, Liquid Filled, 2 In, 60 Psi - Pressure and Vacuum Gauges - Pressure and Vacuum Measuring - 4FKZ4 : Grainger Industrial Supply

 

[tshep]

I would buy what they call an 1/8 pipe (Bourdon tube) gauge.
Most old cars and auto places will have that size,and if it happens to be 1/4 pipe you can adapt it up - and yet still use it for other, more common things. Capillary tubes are usually for temperature - like that copper tube in an older oven.
Every oil pressure problem I have ever had, without an obvious spun bearing noise, was sludge in the pan blocking the pickup screen (even on well changed machines). It's a temperature/air flow thing that can happen even if oil is changed regularly.
I took to soaking screens, in place, in Seafoam, and then scraping screen with wire hook through oil hole. Worked fine, last one I did... Drain the Seafoam and use it over later as gas additive with some oil in it!

 

[bky]

Thank you all for the suggestion and thnak you tshep for linking me to a gauge

 

[PHILIP8N]

Not long after I got my used B8200, there was a thread on triple gauge sets that some TBNers were talking about. I invested $13 in a set- oil pressure, voltage and coolant temp. I made a "console" to mount them, but installing them was easy. I just installed a tee were the oil sender switch was, and bingo- very useful, I think. Seems to me everyone should have such information about how their engines are working.

Nice setup. What does your oil pressure run hot/cold/idle/max rpm? Or just simply the range you normally see? What coolant temp do you stabilize at? Thanks. Philip.

 

[crazyal]

You can just go to your local auto parts store, like AutoZone and pick up a gauge. The gauges usually come with different adapters to work with both SAE and metric fittings. If not they will have any adapters you may need. Chances are there are multiple places you can install the sensor for the pressure gauge. As long as your engine isn't running very little oil will leak out so you can just bring it down to the store with you.

 

[bky]

Well I installed a 60 psi pressure gauge in a tee I installed to keep the oil pressure switch connected. started the engine and maxed out the pressure gauge. warmed up the engine to operating temp and the gauge stayed above 60 psi, I then ramped it to 2000 rpm and the gauge stayed around 60 psi
then i throttled down to idle (around 500 rpm) and gauge dropped to around 55 -60 psi. the light never did come on probably because i was using brass fittings between the pressure switch and the block. I am going to test the switch with air compressor and ohm meter before reinstalling it back in the block. question is was /is the pressure too high?

 

[Chilly807]

60 psi sounds about right, it may be a bit lower fully warmed up. Diesels typically run higher oil pressure than a gas engine. You may want to try a 100 psi gauge, having them maxed out often damages the accuracy.

Sean

 

[bky]

Is it possible to have too much pressure?

 

[Chilly807]

It IS possible, but I don't think that's the case here. In my opinion, you have a sensor problem. The brass couplings conduct better than steel to steel. It's possible that just moving it around a little cured the problem, at least for the moment.

Sean

 

[moored4]

It IS possible, but I don't think that's the case here. In my opinion, you have a sensor problem. The brass couplings conduct better than steel to steel. It's possible that just moving it around a little cured the problem, at least for the moment.

Sean

Sean, I am haveing a problem following this. We are talking PSI, not tempature, What does the type of tubbing/pipe have to do with pressure.
David

 

[irvingj]

I'll also second the thought about the sending unit.

Most of the time, in my experience, the sender was the problem. Sometimes they just get "old" and fail to register properly, but often it's just a small piece of sludge --or similar-- in the sending unit's entry port. You may have dislodged it when you installed the gauge. (They're not called "idiot lights" for nothing!:laughing If the proper range pressure gauge looks OK, and there aren't any bad noises, you should be fine.

 

[Chilly807]

Sean, I am haveing a problem following this. We are talking PSI, not tempature, What does the type of tubbing/pipe have to do with pressure.
David

the light never did come on probably because i was using brass fittings between the pressure switch and the block.

The OP said he was using brass fittings, the pressure switch for the warning light is electric and relies on a good connection between the sensor and the block for a ground. Brass conducts quite well, ergo there should be no problem.

Sean

 

[Max Power]

The OP said he was using brass fittings, the pressure switch for the warning light is electric and relies on a good connection between the sensor and the block for a ground. Brass conducts quite well, ergo there should be no problem.

Sean

that's a stretch. lol