Transmission/hydraulic oil heater

[JCByrd24]

Hi all, wanted to share a piece of great news I recently discovered for fellow cold weather operators. My 186D has always been slow to warm up (hydraulic fluid) when it's cold out (below 35 degrees F or so). The pump whines a little and the loader is slow for a while even after the proper warm up. I was hoping to make this better recently with a fluid/filter change and screen cleaning, but it actually got worse. The fluid is proper grade, but apparently just a little thicker in colder weather than the previous. In my opinion the filter being on the suction side (in addition to the screen) is design flaw. This should have been in return, but oh well. This prompted me to look once again for the yanmar transmission heater referenced in the owners manual. No luck finding the PN online this time around either (and I guessed the dealer would be no go or $$$$). I decided first to take a close look on the tractor in the area the manual shows. Low and behold, the square headed plug just forward of the left rear axle appears to be a simple pipe plug, not some fancy hydraulic fitting. I measured it and it jived with a 1/2" NPT (almost 7/8" diameter), so after a little googling I ordered up one of these:

Kat's 11423 400 Watt 1/2" NPT Frost Plug Heater : Amazon.com : Automotive

I figured for $24 I couldn't go wrong, and I didn't.

I installed today without even draining the fluid, just some quick hands (I could tell after a few turns of the factory plug it was very likely NPT), and tested it out. Even with it plugged in for just 10 minutes or so, the tractor was noticeable happier on start up. I'm a happy guy.

[Scotty Dive]

Was starting the tractor easier too? Any chance you have a picture or the schematic from the manual of where this installed? I gave up on removing the engine block plug so I am very interested in this.

[winston1]

Butting in as usual but if you look on Figure 79 you can see both the engine and transmission heater ports. http://downloads.pfgaustralia.com.au...mar/YM186D.pdf
BH-59100 400 Watt Engine Block Heater Assembly [Replaces YT1446-59100] - $65.00 : DTP, We Know Your Diesel!

Yanmar 2358889 Sailboat Supplies, Engine Parts and Boat Parts

[JCByrd24]

Was starting the tractor easier too? Any chance you have a picture or the schematic from the manual of where this installed? I gave up on removing the engine block plug so I am very interested in this.

No I don't think this will impact the starting, it's quite a distance from the engine. I already have the block/coolant heater as well, it came with the tractor. It works wonders for starting in cold temps. I would try some penetrating oil/heat and a bigger wrench, in my experience the block heater is a must, thermostart alone doesn't cut it. I will get pics of the manual pages soon.