2016 FLRT with a stock 103" Twin Cam engine. Bought this several years ago with 6K on the clock. It sat for long periods as my wife and I negotiated moving to a new city, but I've now run it up to 20K.

Two questions:

1) OEM oil cooler (HD part no. 63083-11A) installed by previous owner began leaking at one inlet at 20K. See photo below for reference. Has anyone else had this issue? If I buy an OEM replacement, will I be back again in another 20K?



2) If I am understanding correctly, there is a thermostat in the oil cooler adaptor assembly, under the plugs at top, as seen in photo below. These 103"s run hot AF on the best of days, and I live in Southcentral Texas. Temps here rarely drop into the 40s, and frequently hit triple digits. Has anyone removed the thermostat from that adaptor so the cooler functions all the time? Can anyone think of a reason not to remove the thermostat?



For further reference, here is the exploded view from the oil cooler kit instructions:



I spent four decades on shovelheads, and worked in a shop for many years. I'm a fair hand with a wrench, but am a babe in the woods when it comes to Twinkie and later engines. Any info would be appreciated.

Thanks.

 

First. An oil cooler is an oil cooler whether it's on a shovel or twinky..

The thermostat is behind the domed screw with the 2 pin holes.

Plug one end of the hose and add compressed air to the other. Toss it into a pail of water and look for bubbles..

 

Bill you may have already checked this, but a bad hose can leak from within and show up on a fitting. Lucky repair if its only a hose.

 

Thanks. I swapped the hose but it still leaked. I haven't pressure-checked the cooler core yet to see where the leak is, but all indications are that it's leaking around that inlet block on the top of the core.

 

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I understand that. I've just never had one with a thermostat before. See previous reference to Texas temperatures.

Thanks. I'll have a look.

Will do. Eliminated the hose per cj5's suggestion. Just haven't gotten to testing the core yet.

 

When the thermostat opens, the oil cooler only can reduce the oil temperature a given maximum amount. So, it won't affect that final temperatures one bit by having it bypass or eliminate the thermostat, it will just take a bit longer for the motor oil to warm up and reach that final temperature. I don't think that really does anything worthwhile since you're not changing that maximum temperature of the oil. Now, a larger cooler would probably reduce that maximum temperature. That might be your best option if you find your existing cooler is leaking.

John

 

One thing to note is that you can't simply remove the thermostat. You have to duplicate it in the closed position.

I removed one from a Jagg adapter it work different than a auto block coolant thermostat. Cooled off it opens and simply allows the oil to bypass the cooler. Don't know about the adapter you have. I have the same on another bike but I simply cleaned the thermostat and reinstalled. It looks exactly the same as the one in the JAG.

I live in socal and so needing the thermostat is pretty much the same plus whenever I ride I typically go at least 35 miles...

BTW it is raining right now and the temps are down to 58 degrees..

 

I put an ultra cool after market on my 2007 Dyna wide glide, the guys said I need not worry till temps stay under 50 degrees. Then all you have to do is cover the cooler so no air flow. Now they also sale an inline bypass, you cut your hoses. Since I live in south Louisiana I don’t really have much to worry about extreme cold.
From the automotive side 185 deg is the coldest you should run your oil to keep sludge down. I do have a fan on mine, but it stays off until engine reaches 280 degrees and off at 260 according to my power vision 3. Fan runs from stop and go traffic. As for as fixing cooler, if you were in lafayette I would call Sid’s radiator repair. Best of luck, as far as the HD parts I just think it was bad luck. They make good stuff but everything breaks. As I quote Doc Harley, if you have to fix it why not up grade it. Look around you might find a better deal, big HD will always be there.

 

Thank you, John. That makes sense.

I looked at the aftermarket coolers, but went with the OEM again for ease of installation. If (when?) this one craps out, I have my eye on a 10-loop cooler from Jagg.

 

Thanks, Max. I think I'm going to leave well enough alone for the time being. Appreciate the info.