Low Oil Pressure Light YMN 3810

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Fat Boy
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Low Oil Pressure Light YMN 3810

Postby Fat Boy » Fri Sep 01, 2017 12:31 pm

Low Pressure light came on while working food plot. Shut engine down immediately and waited 2 hours. Double checked oil level and it was fine. I have added only 45 hours since purchase. Drove back to barn with light flickering only once. After parking, I noticed a trail of drops on on floor and under the tractor. Back tracked leak to the oil pressure sensor. Notice shiny sensor in photo and wet appearance of frame area below sensor. I will change oil/filter anyway, but I am thinking sensor is toast. Any thing else that I need to check?
Attachments
DSC_0003.JPG
Sensor and oily area nearby
DSC_0003.JPG (110.81 KiB) Viewed 369 times
DSC_0004.JPG
Total overnight oil leak amount.
DSC_0004.JPG (81.35 KiB) Viewed 369 times

winston
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Re: Low Oil Pressure Light YMN 3810

Postby winston » Fri Sep 01, 2017 2:54 pm

If the new sensor turns the light out you are probably ok, if not, you might ought to check oil pressure. You refer to your tractor as a YMN. Did you buy this in the DAllas area from VN Tractors? I think they refer to them as YNM. Does your tractor not have dip sticks?

Fat Boy
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Re: Low Oil Pressure Light YMN 3810

Postby Fat Boy » Sat Sep 02, 2017 7:20 am

Purchased 3810D from dealer in Fairview NC. He referenced TX as his distributor. VTEK is manufacturer of front end loader, but I may have assumed incorrectly the YMN.

Yes on current dip sticks for both oil/hydraulics, but current hydraulic cap is plastic/vinyl and the ridge for gripping/turning the cap is nearly 90% gone. Replacement hydraulic cap/dipstick ordered from Hoye earlier is longer than the original. Before I cut to length, I just wanted to be sure that copying the length and markings of the original is OK.

winston
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Re: Low Oil Pressure Light YMN 3810

Postby winston » Sat Sep 02, 2017 7:29 am

Hmmm, so you have to mark the new dipstick. Guess it must be one fits all. Nothing wrong with that as long as you have something to go by.

Norm
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Re: Low Oil Pressure Light YMN 3810

Postby Norm » Sat Sep 02, 2017 1:18 pm

Replace the sender and call it a fix.

alan
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Re: Low Oil Pressure Light YMN 3810

Postby alan » Sat Sep 02, 2017 8:11 pm

The fluid is fussy on some things (right type, water-free, clean) but not level, which you can't handle accurately anyway if there's a loader. As I said, just look down.

Norm
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Re: Low Oil Pressure Light YMN 3810

Postby Norm » Sun Sep 03, 2017 8:01 am

If it has a VTEK loader it's a Vietnamese recon and the dipsticks could be from anything. I would sooner trust the Hoye dipsticks "as is".

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Re: Low Oil Pressure Light YMN 3810

Postby Aaron » Sun Sep 03, 2017 3:13 pm

All of our dipsticks should come ready to use. You should not have to modify them in any way. Email me with your order number or the name on the order and I will see what part you ordered and we can double check it.

Fat Boy
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Re: Low Oil Pressure Light YMN 3810

Postby Fat Boy » Mon Sep 04, 2017 7:58 am

I did swap the sequence of letters. Another rookie mistake. Realized the error of my ways on the country of origin, shortly after the purchase and being made aware of Hoye web page. However, water under the bridge now.

Replacement sending unit and pressure testing gauge should arrive shortly, received note from Hoye that they were sent Friday/Saturday. Changing of the oil did not "fix" the problem. I tightened the sending unit with a turn of about 1/8 inch using pliers. It does not leak anymore, but the low pressure light comes on within a minute of tractor idling in my barn.

I appreciate Hoye checking on the replacement hydraulic dip stick. Good to purchase from a firm that takes time to help their customers.

Fat Boy
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Re: Low Oil Pressure Light YMN 3810

Postby Fat Boy » Sat Sep 09, 2017 2:19 pm

When inserting the brass adapter for the oil pressure sensor replacement, do you have to muscle the adapter into the sensor hole initially or should it turn easily by hand for several turns?

Original sensor can be turned easily by hand either taking off or putting back on; but the brass adapter turns only slightly (1/8 inch maybe) and then stops. The adapter threads appear to me to be more like the new sensor and not like the old sensor which has a more narrow tip.

winston
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Re: Low Oil Pressure Light YMN 3810

Postby winston » Sat Sep 09, 2017 3:50 pm

the original sensor threads are 1/8"BSPT which is 28 threaads per inch. NPT 1/8" threads are 27 per inch.

Aaron
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Re: Low Oil Pressure Light YMN 3810

Postby Aaron » Mon Sep 11, 2017 8:56 am

Are you using thread tape on the adapter? Sometimes that tape will take up too much space and make them hard to screw in. It will probably not turn by hand for several turns but muscling anything that small is risky.

alan
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Re: Low Oil Pressure Light YMN 3810

Postby alan » Mon Sep 11, 2017 12:13 pm

It's a small must-never-leak fitting on a vibrating and temp-changing surface. Thoroughly clean both sets of threads and the surface. Apply a thread-sealer like Lok-Tite. Carefully thread it in. Mound epoxy around the fitting to cancel any bending strain that could eventually weaken the connection at the threads.

Norm
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Re: Low Oil Pressure Light YMN 3810

Postby Norm » Sat Sep 16, 2017 9:00 am

You should not need the adapter to replace the sending unit.

Fat Boy
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Re: Low Oil Pressure Light YMN 3810

Postby Fat Boy » Mon Sep 18, 2017 11:52 am

Thanks for all of the council and advise. I appreciate the response which advised that the brass adapter required for the engine was the 1/8 BSPT male thread.

The reason for the adapter was that the replacement sending unit from Hoye was 1/8 NPT as well as the threads on Hoye's oil pressure testing kit.

My problem for the adapter not threading easily was that the brass adapter was not BSPT male threaded. The 2 brass adapters I ordered from Hoye were 1/8 NPT male thread. Hoye must have a mislabeled bin or someone restocked incorrectly. (I ordered both a pressure test kit with adapter and then made a follow up replacement adapter order a week or so later from Hoye and both brass adapters were the same...1/8 NPT male thread.) I will contact Hoye shortly about the incorrect adapters as they were very responsive about correcting an error with one order in the past.

After reading the earlier post about BSPT, I ordered the BSPT male thread with 1/8 NPT female thread brass adapter thru Amazon. The Amazon brass adapter spun on easily without any "muscling" required.

As was suggested I used loctite on the adapter thread into the engine block. I also installed a brass "T" to have a "port" both for the sending sensor and for the test oil pressure gauge. I may add a permanent mechanical oil pressure gauge to the dash later.

The replacement sending sensor unit works as it suppose too. The unit comes on for a few seconds at start up and then turns off.

The test gauge shows readings of 65 lbs on start up and then the pressure drops steadily to 45 lbs after 4-5 minutes of warming up (at idle speed). I pulled a harrow disc for 40 minutes and rechecked the pressure again and the oil pressure had elevated to 55-60 lbs, but dropped to 45 lbs after a few minutes when the throttle was reduced back to idling.

I am happy again, unless, of course, I now learn from you all that there is a problem with the pressure peaking at 65 lbs at start up!

Any idea as to the "life" of a sending sensor?


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