What did you do with your Chinese baby digger today?

[mike0000]

Good work. I love to see the data you have taken to see the results of your cooling efforts. I assume you have the 420cc gasoline engine, without ducted flywheel fan.

What was the ambient temp when you were taking measurements?

Thank you, mini has the Briggs and Stratton 13.5, I assumed it had a ducted flywheel fan, there is venting around the pull start., Temps. Are 90 plus, 95 while running it today, unfortunately,I did not see a drop in hydraulic oil temperature after my 1 hr run today (test today was for the additional fan shroud on the oil cooler). Hydraulic oil in tank was 150. Hydraulic oil *edit* fuel is staying under 130.
I think the next thing to do is reverse polarity on the added 7” fan, this would have both fans pulling in as opposed to current setup with oil cooler fan pulling in and aux. fan pulling out. If that doesn’t improve temperature of the hydraulic oil, I’m considering a third fan under the seat, which may overtax the engine’s electrical output.
Mike

 

[dfkrug]

Thank you, mini has the Briggs and Stratton 13.5, I assumed it had a ducted flywheel fan, there is venting around the pull start., Temps. Are 90 plus, 95 while running it today, unfortunately,I did not see a drop in hydraulic oil temperature after my 1 hr run today (test today was for the additional fan shroud on the oil cooler).

To duct the flywheel fan properly, you have to replace the pull starter with the duct. This will get you the most air circulation from outside the house. I understand that this is in the way of the location where some makers have put the oil cooler.

I generally stop operating when my oil temp reaches 50C, but remember that my thermocouple is inside the hyd tank, towards the bottom. 60-70C is probably fine.

I don't work outside when it is 90F ambient.

 

[mike0000]

To duct the flywheel fan properly, you have to replace the pull starter with the duct.
This will get you the most air circulation from outside the house. I understand that this is in the way of the location where some makers have put the oil cooler.

I generally stop operating when my oil temp reaches 50C, but remember that my thermocouple is inside the hyd tank, towards the bottom. 60-70C is probably fine.

I don't work outside when it is 90F ambient.

My oil cooler is on the opposite side of the pull start. That’s news to me about switching out the pull start, thank you, I’ll have to look for that duct as an option for more air flow.

 

[drawthree]

To duct the flywheel fan properly, you have to replace the pull starter with the duct.

Has anyone found a duct that can be purchased for the 13.5 briggs motors? I've looked a couple times but have not been able to find anything. I have thoughts about making one but that takes more time than I have to spare right now.

 

[mike0000]

Has anyone found a duct that can be purchased for the 13.5 briggs motors? I've looked a couple times but have not been able to find anything. I have thoughts about making one but that takes more time than I have to spare right now.

I’d like to know the same drawthree, I did some internet searching but haven’t found anything.

 

[D'oh]

Since running mine with the Rear Cover Removed, I have not had any Over Heating. Muffler wrapped in Heat Tape

 

[mike0000]

Since running mine with the Rear Cover Removed, I have not had any Over Heating. Muffler wrapped in Heat Tape

The back two supports of my ROPS are mounted to the rear cover, or I’d probably do the same.
I reversed polarity of the added fan, so both it and the oil cooler fan pull in.
I ran it this morning for an hour and hyd. Oil was 143deg.F, but ambient temperature is 85, yesterday was 95.

 

[drawthree]

I just added a hydraulic oil cooler today. I had to cut off the mounting ears to make it fit but it turned out pretty good. Pictures attached.

 

[dfkrug]

Has anyone found a duct that can be purchased for the 13.5 briggs motors? I've looked a couple times but have not been able to find anything. I have thoughts about making one but that takes more time than I have to spare right now.

I was fortunate that my machine had its ChangChai diesel removed before shipping, and the air duct left installed. It was not hard to fabricate the steel hoops to support it with my new Duromax 420 engine.

It would not be hard to get some foil dryer vent flex hose and do a similar thing.

 

[mike0000]

I was fortunate that my machine had its ChangChai diesel removed before shipping, and the air duct left installed. It was not hard to fabricate the steel hoops to support it with my new Duromax 420 engine.

It would not be hard to get some foil dryer vent flex hose and do a similar thing.

Thanks for posting that picture and info

 

[dfkrug]

Thanks for posting that picture and info

It is all in post #47 of my Modification thread:

Importing and modifying a new mini excavator from China

I replaced the hydraulic return line to the tank with the filtration system shown above. The original fitting on the tank had 2 lines returning fluid. One was out of the stack valve, and the other smaller hose came out of the distribution valve (photo). The distribution valve allows the house...

www.tractorbynet.com

 

[2manyrocks]

FWIW, Mike Festiva has posted a YT video of how he adapted a walk behind string trimmer to his mini EX.

 

[dfkrug]

FWIW, Mike Festiva has posted a YT video of how he adapted a walk behind string trimmer to his mini EX.

Here it is:

He did a good job. I really liked his CNC plasma setup, too.

 

[Sonny580]

workin on field lile with the L-12 and its VERY slow going! Ground hard and rubbery at tile depth and digger not suitable for this kind of work! Not enough power for sure! Need a 20 horse motor on it as min. I keep scratchin and thats all it is, cause I dont have a runnin hoe to do it with.
Looks like I have 800 to 1,000 feet to dig out and replace with new tile.
I only work a few hours each day cause thats all I can stand.
got 200 feet uncovered in 3 days,---now to yank out old tile, put bottom on grade then drop in new plastic field tile. Some is 10" and some 5 "

 

[drawthree]

Not enough power for sure! Need a 20 horse motor on it as min.

Is your engine struggling to keep up with the demand, or is the engine staying strong and your just running up against the hydraulic pressure bypass? I ask because I have been digging in rocky soil lately and was getting nowhere. The engine was running plenty strong but I'd pull on a rock and didn't have enough hydraulic pressure to move it - the hydraulics just kept hitting the bypass. I got a gauge and checked and my bypass was set at 2200lbs. I bumped it up to 3000lbs and the engine was still keeping right up with no trouble so that's where I left it.

Night and day difference. Now it moves rocks.

 

[Sonny580]

lack of motor power---kills that sucker dead in its tracks!!

 

[drawthree]

lack of motor power---kills that sucker dead in its tracks!!

Interesting. Even with my hydraulic pressure set at 3000lbs I can run the little briggs in my Typhon at just over 3/4 throttle and it barely buckles down when I pull on a rock hard enough to hit the bypass.

 

[Sonny580]

Depressing to say the least. This motor was junk when I bought the digger new,---it was full of saltwater and crud when it came out of the shipping container from chimna and both valves were stuck open. Top of piston was full of burned crud on it as well. Factory stuck some junk test motor on it that probably has a thousand hours on it and sent the digger out the door and I got stuck with it!

 

[dfkrug]

This motor was junk when I bought the digger new,-

Yeah, it was a freakish thing that happened to you, SONNY.

I and at least one other person I talk with frequently bought the DuroMax 420 engines, shipped from SoCal. They have been super-reliable and run very well, even after 6 years, and hundreds of hours. That engine is made by LCT, a US company with factory in China. The one that acquired the Tecumseh name years ago. It was about $300 back then....about $400 now.

Have you considered swapping your engine for a new one?

 

[Sonny580]

cant afford to put a bigger one in it right now BUT still eying one of my Kohler 20's out of an old sunstar. I know that would run it!
Today I got another 40' of tile uncovered with it slow as molassas but its all I have and the tile has to be replaced so thats #1 right now.