Modifying Swivel Brass water cooling fittings for better flow

[ray schrauwen]

I was curious as to why such a large motor as my FC 4092- 2200kv was getting so hot. Never baked it but, up to 150 at times with what should not be that hot of a setup.

Today I thought maybe I'll change them out for some I have from hobby king, since the original fittings are 10-32 and hk ones were 6mm I took the swivel fitting off the cooler to find a somewhat of a surprise.

Inside the swivel 90* fittings is a major restriction! As pictures will show the inner part of the fitting drops the ID of intake from 3/32" down to 1/2 that of 1/16" !!!

Time to modify! Be careful when you take them apart as they have tiny o-rings that can get lost or damaged easy.

You should use a drill press and a flat jaw vise, if you don't have these things you might want to ask a friend.

The inner part has a horizontal hole that goes through both sides is only 1/16" and the vertical portion is 3/32" like the intake. I started by clamping the 'nut' head into the vise very tight and first used a 5/64" bit to open it up then a 7/64" bit to finish. After that I turned it 90* in the vise and drill out the vertical portion to 7/64".

This is where I am at now and I'm thinking since the intakes are too thin to drill out, I might just take the barbed portions off the Chinese fittings and swap them for the originals but, I haven't got that far yet.

It should not be to hard I have some SatBright to do it and the new intakes are a nice 9/64" 'ish ID.

Here are some pics showing originals, modified and the hk ones that don't swivel.

I have since de-burred the drill holes from what you see in the pics is after raw drilling.

Hopefully you find this informative and helpful. I'm sure my motor will run cooler now with the mods.

Cheers

Sorry pics aren't the greatest, old camera.

[properchopper]

The stock 90 deg fittings that come with the machined aluminum jackets are rather tiny, i.d.wise. The Aeromarine 10-32's are bigger, and the Leopard-style 5mm are bigger yet :

6-5-13072.JPG 6-5-13074.JPG

A little of this :

DSC04577-1.JPG


The Aeromarine ones need to be trimmed inside so they don't bottom on the motor can :

DSC04580.JPG


The "Leopard style" ones have just enough thread. Carefully coat the threads with JB Qwick, & aim where you want it to point. (It'll stay there but can be broken loose if need be to re-aim for another application) :

DSC04582.JPG

[Mike Caruso]

Attention to detail nice

[properchopper]

Attention to detail nice

Mike, Thanks ! [ Ray please forgive the brazen thread hijack ] - I've found that attention to detail during the build minimizes the fixing later on.

Some details on my Cheetah : hard waterlines supported by hand-made cf holders, esc trigger wire passes through square tubing, tight esc battery inputs . Scratch built motor mount side plates. Way cleaner than my earlier "spaghetti-bowl" builds


DSC04859.JPG DSC04860.JPG DSC04861.JPG

[HRC]

Hey Guys,
I agree there is room for improvement with the adjustable fittings used on the HRC jackets but at what price. I can only speak for the HRC jackets.

The issue is not the (2) 1/16” holes on the stem but the clearance between the O.D. of the stem and the I.D. of the body. At about .025 clearances I was very skeptical about using them. After some good hard test runs the motor temps were in the 110 to 130 degree range depending on the motor being used. I think we can all agree 110 to 130 is acceptable. Lower would be better for sure.

We will be and have been looking into having these fittings modified for more clearance
We are always open for suggestions and ideas for improvements.
Thanks, Dave
.

[Cooper]

I very much agree, I too was amazed at the pinhole for water in the adjustable fittings. I also swaped out those for bigger fittings. After lining up to the direction I wanted I just used some thick ca glue to secure them and make watertight. Haven't had and leaks or problems since. And after they were good and dry I went back and ground down any protrusion into the cooling jacket as like said the clearance isn't much. Looks good so far!!

[properchopper]

Dave,

Thanks for your response. The HRC jackets are well designed, have nice large o-rings and install and fit nicely. I'll admit that it must be a challenge to produce a universal piece that works for all applications and pleases everyone. True, every once in a while I'll have to relocate an input or output but it's easy to do. Also never had a problem with the supplied fittings on my better motors BUT (as addressed by another current thread) many of us are finding a frustrating incidence of heat related issues with the current crop Ltd motors and struggling to "up" the cooling flow to prevent these incidents. My testing indicates that more waterflow with larger fittings (if there is actually an improvement) on Ltd motors isn't the answer. If in fact the later Ltd motors aren't as robust as the earlier examples the best answer so far is to adjust the setup, period.

[ReddyWatts]

[HRC]

Dave,

Thanks for your response. The HRC jackets are well designed, have nice large o-rings and install and fit nicely. I'll admit that it must be a challenge to produce a universal piece that works for all applications and pleases everyone. True, every once in a while I'll have to relocate an input or output but it's easy to do. Also never had a problem with the supplied fittings on my better motors BUT (as addressed by another current thread) many of us are finding a frustrating incidence of heat related issues with the current crop Ltd motors and struggling to "up" the cooling flow to prevent these incidents. My testing indicates that more waterflow with larger fittings (if there is actually an improvement) on Ltd motors isn't the answer. If in fact the later Ltd motors aren't as robust as the earlier examples the best answer so far is to adjust the setup, period.

Thanks Tony I appreciate that. Yes it is a challenge at times to make a product that is of quality and maintain a price that is acceptable in today’s market.
Our constant quest for speed and using budget motors some times do not mix but we do it anyway.
On the flip side, without lower priced products our hobby would not be where it is today.
Dave

[Mike Caruso]

Read it and weep for all those that still think slowing water down is a good idea.

http://www.flowkoolerwaterpumps.com/tech_support.html

Go fast have fun and burn up less parts.......unless it's SAW LOL

Great job on the fittings guys good detective work. Now who will make a simple way to add a spiral to all motor water jackets? JB Weld and a small piece of wire (blows) a racing term meaning it is a pain to try and fit it to the case. I still have to test it I am sure it will help cool the case better. But since I have learned that the heat is in the stator Hmmm. Ok I would like to try a STATOR mounted on a very hard TUBE no flexing allowed it might cool better. Tube's do flex less that shafts anyway. Tony ever try anything like that? Ray? Anyone LOL?

[HRC]

Something else we need to consider. The 2.4.6 pole motors have different efficiency ratings. The 2 pole motors are less efficient resulting in more heat and other factors.
This is the formula I typically use to figure a heat transfer flow rate. This is a standard formula used to figure out most heat transfer numbers.

”Media specific heat, flow rate over area squared, and a delta t.”

And a lot of testing

[jcald2000]

The Stator is a tube full of wire and back iron, the heat comes from the wires. Rotor does not produce heat as it spins the prop.
You want to watercool the wires inside the motor?

[Mike Caruso]

Something else we need to consider. The 2.4.6 pole motors have different efficiency ratings. The 2 pole motors are less efficient resulting in more heat and other factors.
This is the formula I typically use to figure a heat transfer flow rate. This is a standard formula used to figure out most heat transfer numbers.

”Media specific heat, flow rate over area squared, and a delta t.”

And a lot of testing

Thanks good tip and always you have to work on anything to get it better..........after you make it worse about 50 different times LOL