Kubota block heaters

Teikas Dad · Dec 26, 2014

I searched and I searched, honest I did....and I couldn't find the answer.

I have a B3200 that I'm thinking about putting either a block heater or inline radiator hose heater on. I know for the Kubota block heater you unscrew one of plugs on the side of the motor. Does the block heater screw into the opening or is it a press in style? If it's press in then I think I'll go with the inline radiator hose heater.

Kanook · Dec 26, 2014

If the plug that gets removed is a screw in type, the block heater that is inserted would be a threaded type. If the plug is a pop out then the heater replacing it is tapped in. I have had both type over the years and no issues with either....I have not been impressed with the performance and reliability of the 2 rad hose types that I have had....just my personal experience.

xring100 · Dec 26, 2014

Im pretty sure the plugs are threaded with pipe thread. plan on it taking several hundred ft - lbs to break it free mine required me 240 lbs jumping on the breaker bar. Seal it with and anerobic thread sealant. I tried tape and had a slight leak twice. Not fun draining the coolant 3 times.
If i remember the one on my tractor was probably 1 1/8" thread and took somewhere in the range of an 18-21mm allen socket. My neighbors old b2400 was also threaded

Teikas Dad · Dec 26, 2014

Thanks guys, next question. I looked on Ebay and there are several OEM plugs listed but there are some that have a longer heating element. The OEM part number plug heating element barely sticks out past the end of the brass fitting. In my mind the ones that stick out longer provide a larger heating surface and should work better. They're listed at 400 watts and the seller says they'll fit B and L series tractors. However, I'm concerned that the longer element might hit the inside of the block.

Here's the link to one of the longer ones: Kubota Tractor Block Heater Freeze Plug Heater New | eBay

Here's a link to the OEM part: Kubota Block Heater Part #70000-73274

What do you think?

xring100 · Dec 26, 2014

I'd just go for stock My 85 hp 3.8 L holds more 9.5 quart of antifreeze and also uses a 400 or 450 watt element. At -5 °F I Will heat the coolant up above 32°F (my glow plugs will not come on above freezing.) In 1 - 1.5 hours. The placement in the block is in theory supposed to create a thermal current that circulates the coolant through the engine. I could not tell you how thick the water jacket is on mine let alone your tractor.

rScotty · Dec 27, 2014

I'd go with stock, too. That's what I did on mine. That way you know it fits the space in the water jacket and also avoids the hassle of figuring out if that part has US pipe threads or Metric pipe threads. Those pipe threads are too close for comfort, but still not quite the same.
The OEM part is beautifully made, and costs less. Throwing a tarp over the hood will make it heat up faster.
luck, rScotty

Teikas Dad · Dec 27, 2014

OEM it is! Thanks for the guidance, this site is the best! What did we do before the internet...other than booger up most things we tried to fix?

wmonroe · Dec 27, 2014

This reminds me I need to order a block heater for my 5240. Gonna go with the kubota unit.

sixdogs · Dec 27, 2014

Good idea to go with OEM Kubota. My block heater worked really good compared with a simple radiator hose aftermarket heater. those weren't very good.

There is also another type I used that worked well but still not as good as OEM block heater. It was a lower radiator hose heater with a tank on it and a separate line that connected to the drain plug on the block. It caused the water to circulate and was much better than the simple hose kind. Still not as good as the block OEM but an honorable mention.

sandyc · Dec 29, 2014

I went with the OEM for my 2620 and the only thing I wish I did was use tape like they said to. I tried the blue paste and that leaked so I drained the rad again and taped it up like I should have the first time.....no leaks and works great.

Mendonsy · Dec 29, 2014

I installed the OEM part from Messick's also using thread seal tape. No problems at all with that.
One note though .... the factory part is 3/4" pipe thread. Some engines (my B7500 for example) require a 1" x 3/4" threaded brass bushing to install them. There is an note about that in the instructions but it is easy to miss.

MessickFarmEqu · Dec 29, 2014

only use OEM. If an aftermarket over heats the fluids, then your glow plugs won't turn on.

xring100 · Dec 29, 2014

MessickFarmEqu said:
only use OEM. If an aftermarket over heats the fluids, then your glow plugs won't turn on.

I agree on using OEN byt my OEM plug heats the coolant well over 32°F on mu M8540 and the glow plugs dont turn on yet it starts just fine.

For everyone else:
You dont want to use regular pipe dope. I could not get 4 wraps to seal on my plug of regular teflon tape which upon reading an article standard rolls are only rated to 3/4" and mine was 1 1/8".
It would seal for a while but after a few heat cycles it would start weeping and further tightening would not resolve the issue. It was wrapped in the proper direction to prevent it from unraveling.

The oem block plug is sealed with an anerobic thread sealant so i ultimately sealed my block heater the same way. It is similar to loctite thread locker.

Here is the permatex version.
Thread Sealants : Permatex

sixdogs · Dec 29, 2014

xring100 said:
I agree on using OEN byt my OEM plug heats the coolant well over 32°F on mu M8540 and the glow plugs dont turn on yet it starts just fine.

For everyone else:
You dont want to use regular pipe dope. I could not get 4 wraps to seal on my plug of regular teflon tape which upon reading an article standard rolls are only rated to 3/4" and mine was 1 1/8".
It would seal for a while but after a few heat cycles it would start weeping and further tightening would not resolve the issue. It was wrapped in the proper direction to prevent it from unraveling.

The oem block plug is sealed with an anerobic thread sealant so i ultimately sealed my block heater the same way. It is similar to loctite thread locker.

Here is the permatex version.
Thread Sealants : Permatex

That is good advice. Thanks for posting it.

xring100 · Dec 29, 2014

sixdogs said:
That is good advice. Thanks for posting it.

Thanks your welcome.

After I failed to seal it the second time with tape. I went to Auto Value and bought the thread sealant. I remembered seeing it next to the anerobic gasket maker which i used for sealing the two halves of my manual transmission on my Saturn i had to tear it down an replace the input shaft seal it sat for a couple if years and devolped a leak immediately after pullling it out of storage

Teikas Dad · Dec 31, 2014

OK, after checking with three local Kubota dealers I finally found one that had the block heater in stock. I stopped this afternoon and picked it up. Then a quick stop at HF to get the 17mm hex head socket and AutoZone next door for the Permatex thread sealant. They had the high heat sealant which according to the package is identical to the one XRing suggested.

Now, where do I find the plug in the block that I have to swap out on a B3200? Left side, right side, front, back?

wmonroe · Dec 31, 2014

Teikas Dad said:
OK, after checking with three local Kubota dealers I finally found one that had the block heater in stock. I stopped this afternoon and picked it up. Then a quick stop at HF to get the 17mm hex head socket and AutoZone next door for the Permatex thread sealant. They had the high heat sealant which according to the package is identical to the one XRing suggested. Now, where do I find the plug in the block that I have to swap out on a B3200? Left side, right side, front, back?

Can't help on where it goes on your machine but maybe someone else will chime in. Did any instructions come with it?

xring100 · Jan 1, 2015

Teikas Dad said:
OK, after checking with three local Kubota dealers I finally found one that had the block heater in stock. I stopped this afternoon and picked it up. Then a quick stop at HF to get the 17mm hex head socket and AutoZone next door for the Permatex thread sealant. They had the high heat sealant which according to the package is identical to the one XRing suggested.

Now, where do I find the plug in the block that I have to swap out on a B3200? Left side, right side, front, back?

Awesome. I have a bigger block tractor my instructions showed a illustration of the motor. Mine is located on the right hand back corner of the block behind the water separator (i had to remove the bowl to get access) However older versions actually had one on the left side but mine has an egr collant line that location.
Neighbors old b2400 is also right rear. I'm pretty sure you wont find many plugs in the block with that size hex. There may be more than one to accommodate different orientation in various equipment that block may be in. I.E. generator, zero turn, skid steer, etc.

Mendonsy · Jan 1, 2015

Teikas Dad said:
Now, where do I find the plug in the block that I have to swap out on a B3200? Left side, right side, front, back?

On my B7500 it is a 17mm hex plug on the left side in front of and slightly above the starter. Dunno about the b3200 engine??

Teikas Dad · Jan 1, 2015

Mistake #1, I didn't even look at the directions! Some of the other posts said they were kind of generic in nature. I'll search the block for a 17mm hex head plug and see how many there are.....hopefully there's only one.
Thanks for the replies.