Liebherr 944B
 

I've been waiting and saving for a long time to buy an excavator and its finally arrived, shame its damaged, see rant here

This is what i bought:

http://i1252.photobucket.com/albums/...ps767ce8d9.jpg

Should load the MB nicely (once the booms fixed of course!)

http://i1252.photobucket.com/albums/...psbc2e4032.jpg

I've played around with the radio and added a few mixes so the pump only comes on when the sticks are moved, although the futaba fx-20 seems very limited when compared to my Taranis so may end up swapping it over.

I have a few mods in mind, such as a sound unit etc but need to save up some more and wait until its fixed.

According to premacon and ths,
"Boom and stick are made of aluminium, hard PVC and Pertinax in a layer system with the layers glued and screwed together"
Has anyone tried to machine this?

Cheers for looking
Stu

Re: Liebherr 944B
 

A very nice machine! The German models are reliable.

Re: Liebherr 944B
 

Congratulations Stu on a very fine purchase. :cool:

I feel your pain about the damage caused by the carrier, hopefully proper compensation is made and you can get this beautiful machine back in 1st class working condition. ;)

Your hydraulic mixes, I'm not familiar with the Premacon models, but I do believe they use the same 0,3ml/rev Jung pump that my Fumotec models use with a big brushless drive motor? The initial Amp draw just to start that brushless motor continually will create excessive heat build up within your esc & then the thermal protection will kick in & time out the esc till it cools. It's better to have at least 20% motor activation at all times of intermittent digging. Shut the pump off via a switch when the trk is full.

Re: Liebherr 944B
 

Thanks Joe and your right about the type of pump/motor, I wondered why it cut out after a short while:D

I have the pump on a rotary knob as well as the mixes so can switch it on first and then let the mixes ramp it up when needed.

Its quite noisy with the pump running but I've found out this is due to vibration through the base plate, its solid mounted at the mo and was wondering about some kind of rubber mount?
Its so much quieter when unbolted from the base. I don't have much room to raise the pump though.

I've ordered a couple of 4000mah lipo's, what sort of run time would you expect with the pump running all the time?

Really pleased with it so far, hydraulics are very smooth and can't wait to do some diggin, just got to repair it first!

Re: Liebherr 944B
 

I use 4s 5000, easy digging is over an hour, hard digging about 40-50 minutes.

The latest models from Fumotec have rubber feet about 8mm tall. If nothing else shorter available, I'm sure you could cut out a square piece of rubber from tractor tire tube, the type that are filled with chloride as they much thicker than a car tire tube. But maybe a car tire tube would be enough. :thinking:

http://img.photobucket.com/albums/v1...ps592b35ff.jpg

Re: Liebherr 944B
 

Maybe it could be worth making these for our Varios Joe?

Less sound less vibrations, sounds good to me!

(sorry for taking up space in your thread) :)

Nice excavator you got there, too bad on the damage, hope you can work it out.

Re: Liebherr 944B
 

Rubber fuel line is quick and easy, I used it on my pickup's little air compressor.
Cheers, Neil.

Re: Liebherr 944B
 

Thats exactly what I was thinking of, have ordered some off ebay. Can you run these motors on a 4s ok?

I've put a piece of 3mm rubber under it for now, its a lot better but still get the vibration through the mounting bolts.

http://i1252.photobucket.com/albums/...ps68efbe7c.jpg

After about an hour last night it looked like this:

http://i1252.photobucket.com/albums/...pseae8e2f3.jpg

http://i1252.photobucket.com/albums/...ps4665b43f.jpg

Then spent this afternoon milling and came up with this (love my old bridgeport:D):

http://i1252.photobucket.com/albums/...ps2290c5f5.jpg

http://i1252.photobucket.com/albums/...ps590f3502.jpg

http://i1252.photobucket.com/albums/...ps27e19839.jpg

http://i1252.photobucket.com/albums/...ps5b90f33b.jpg

http://i1252.photobucket.com/albums/...psb2e50128.jpg

Even if/when I do get the compo, I'm fed up with Premacon/THS not answering emails so thought I'd give it a go repairing it.

I think once its bolted and glued in place then painted should look ok and will probably be stronger than the original, may even make a complete new boom in the future.

Not sure whether to make some brass bushes for the pivot or just leave the steel pin in the ally with a splodge of grease???

Now where to find Liebherr yellow, or do I go white:thinking:

Re: Liebherr 944B
 

Try this http://baumaschinen-modelle.net/en/reports/tips/colours

Re: Liebherr 944B
 

Good work on the repair :cool: .... I gotta get a bigger mill someday. :rolleyes:

How about a picture of the end of the boom where it is cut?

Premacon & THS split more than a yr ago.

My Fumotec models use an ABS bushing in the two plates - the cradle that the boom fits too. You probably should consider doing something to prevent oblonging holes.

My 850 is running 4s, but the pump & motor have a belt reduction of 2,5:1. On 4s the pump is spinning approx. 4000rpm. I see your model is direct drive with no gearhead reduction. I have had no problems running the pump @4000rpm, I don't know what the limit is, but perhaps you could check the current rpm your's is rotating and go from there. From what Premacon model excavators I have seen run in videos, the hyd movements seem too quick as it with those small boom/stick configurations & small bore/short stroke cyls.

I don't think you'll need 4s, and I don't intend to use 4s either in my smaller Fumotec 490 hoe - as the bores are considerably smaller vs the 850 cyls @18 (B&B) & 21mm(S).

Re: Liebherr 944B
 

Hello If I was you and went through all that trouble I would definitely put in Brass bushings. You have gone this far and it is apart so do it right now. Ed

Re: Liebherr 944B
 

Thanks for the paint link Bo.

Here's a pic of the boom after cutting with the hacksaw:

http://i1252.photobucket.com/albums/...psa57ce7c5.jpg

Got it drilled and tapped today:

http://i1252.photobucket.com/albums/...ps3e55f336.jpg

Am going to fit some brass bushes, it makes sense to do it now, may try to salvage the original first before making some.

Yeah I know that premacon and THS split, I've emailed them both but no answers yet although I did get a response from Premacon through this forum at the beginning of the week, nothing since.

Mine is 2 yrs old and was sold by"Liebherr-modelle" and has "THS" engraved inside the body parts:

http://i1252.photobucket.com/albums/...ps512f5155.jpg

I was just curious about the 4s, I think your right that mine will be fine on a 3s, the hydraulics seem plenty fast enough, I will check the motor rpm when its back together.
Cheers
Stu

Re: Liebherr 944B
 

Stu,
Liebherr Modelle is now know as Premacon

FYI on the pump...

There is a newer one out which is much quieter, Premacon has it on their website. If I recall correctly 3s is the maximum for this pump, and yes it works pretty well.

I am still running the older one as well... I must admit I never thought of the rubber blocks... I should have. But then the noise isn't too loud on mine, and when other trucks are running at shows and such, you definitely can't hear it.

I do recall another customer replacing their standard boom with a demolition one, if I can find the link I will pass it on. Finally I have the same THS marking on mine, as stated by Lil Giants THS and Premacon were working together for a while.

Cheers,
Andrew P.

Re: Liebherr 944B
 

Great repair and interesting to see how those booms are made!

Since you are in France, why not give the people at Premacon a phone call? Faster than writing an email and waiting for reply.

Hope you get it sorted soon and at least get some compensation for the trouble caused by customs/shipper!

Cheers!

Stephan

Re: Liebherr 944B
 

Any idea why the new pump is quieter? is it a different internal design or the drive system? or is just because its on rubber mounts???

Mines not super loud but noticible that its reverberating through the base plate, if you unbolt it and hold away from the base you will notice a huge difference.

I will shoot a before and after vid once my rubber mounts arrive.

I'm at work when they are open and mobile reception here isn't great so its easier to email.

Got a response from Premacon this week, a new boom is 400 euros and the dipper cylinder is 200 euros.

Still waiting for oz post to get back with an answer re compensation, should let us know by wednesday next week.

So i've been continuing with my repair job, glued and screwed my new piece on, filled the screw heads and painted it:

http://i1252.photobucket.com/albums/...ps2f409262.jpg

http://i1252.photobucket.com/albums/...psb21a4b67.jpg

http://i1252.photobucket.com/albums/...ps94d3f2db.jpg

Its not a bad paint match, liebherr don't use a RAL colour so used the nearest I could find, once cut back and polished should be ok me thinks. Just got to wait for it to dry now.

I want to add a filter to the hydraulic system, where should I plumb it in, on the return to tank or the suction side of the pump?

Also what would you recommend for hydraulic oil?

Cheers
Stu

Re: Liebherr 944B
 

Great job, it blends very well!!

Re: Liebherr 944B
 

Better than new I say!

Re: Liebherr 944B
 

That repair will hardly be noticeable when you re-install the boom.

On my Fumotec digger the oil filters are in the return lines. (there are 2 of those in the PC490)

The hydraulic oil you can order from the Premacon shop.
For what it's worth: from the manual of their Wheel Loader L576 2plus2: Refilling only with our hydraulic oil No.: 61000012. Wrong oil can damage of the seals.

Re: Liebherr 944B
 

The filter can be installed between the return line on valve block and tank... Putting on the feed side causes challenges with oil pickup.

Cheers,
Ap
P.s. Premacon use a hlp 25 oil

Re: Liebherr 944B
 

Thanks guys, its back together:

http://i1252.photobucket.com/albums/...ps1341f0bb.jpg

Made a couple of vids, testing out the pump with it bolted down to the base plate, after 1.30 mins its un-bolted sitting on a piece of foam rubber.

Pump test

First attempt at digging:D

Digging

I have 2 return lines back to the tank, 1 goes through the prv, which one should I put the filter in?

I will look for some hlp-25, on a french forum they are suggesting ATF, I thought that would damage the seals?

Cheers
Stu

Re: Liebherr 944B
 

Hello Stu great fix and it is better than new, should be stronger now. Ed

Re: Liebherr 944B
 

Thanks Ed, i agree, I thinks its probably stronger.

Got my little pump mounts on, had to mill out the base of the pump mount to reduce the height:

http://i1252.photobucket.com/albums/...ps59726ff0.jpg

http://i1252.photobucket.com/albums/...ps2ab9b6e9.jpg

Made a new vid: video

I think its quieter with the new mounts in, in the future though I think I'm going to swop it out for the new pump/plantary/motor combo.

Cheers
Stu

Re: Liebherr 944B
 

Nice job on the boom fix. I think its even stronger than original.
I just came across the difference between THS and Premacon 944b and can be seen here: https://translate.google.com/transla...868&edit-text=

Re: Liebherr 944B
 

Yup... I think however that is for newer machines than Stu's... Or mine...

Stu,

I'll be interested to hear how you go with the new pump if you go down that path.

Cheers,
Ap

Re: Liebherr 944B
 

I think your right Ap, its for the newer models.

Found a buyer for my current pump/motor setup (my dad wants it for a project he's working on) so have ordered the new pump, will let you know once I get it.

Went to my local model club on Sat afternoon, the pump mounts make a big difference, you could hardly hear it over the bruder converts Video sorry for the music! twasn't me.

Cheers
Stu

Re: Liebherr 944B
 

So what's your dad building?

From the pump I see in Cooper's Premacon hyd package, I have the same motor/pump in my Fumotec 490 hoe, it's very quiet! :cool:

Re: Liebherr 944B
 

Its a 1/6th scale Comet tank based on an Armortek kit.
He's fitting it with a dozer blade and hiab, he's not in to forums so maybe I'll start a thread on it.

Re: Liebherr 944B
 

Good job on the fix!

Re: Liebherr 944B
 

Thats good to know, I've watched a few on youtube and they do seem pretty quiet but first hand knowledge is always better!

They are made by Martin Kampshoff

A really helpful guy, told me which one I needed to order, the one I have is a 4002 which produces 900ml/m @ 3500rpm direct drive, the new one I've ordered is a 4003 which is a higher capacity pump but still produces 900ml/min but @ 2500rpm through the planetary drive, motor spins at 10,000 rpm = less power consumption and noise.


New Video with sound module

cheers
Stu

Re: Liebherr 944B
 

Goodies arrived from chez Premacon:

http://i1252.photobucket.com/albums/...ps6657315a.jpg

http://i1252.photobucket.com/albums/...pse7357605.jpg

http://i1252.photobucket.com/albums/...psb5d1b8f6.jpg

New pump and filter are in:

http://i1252.photobucket.com/albums/...pslheucto6.jpg

http://i1252.photobucket.com/albums/...psganyqya0.jpg

Video Testing new pump/motor unit

Cheers
Stu

Re: Liebherr 944B
 

do you have a link to where you got the sound card, it sounds awesome.

Re: Liebherr 944B
 

Sounds alot quieter with the new pump setup. Did you notice any improvements in the movements?

Re: Liebherr 944B
 

Thanks Andy, I'm really pleased with the sound, its a USM-RC2 by Beier I have one in my JD 9530 too, user programmable on the PC using there software, does all the lights and additional sounds aswell as an mp3 player, awesome piece of kit.

I created the sound files myself from youtube and edited them using Audacity.

The new pump/motor combo is a vast improvement, so much quieter, uses less power so longer run times and yes I think the movement is smoother and more precise.

After a long day at a Model Expo (Pics) with the local club/Rc Forum on Sunday, I noticed an oil leak, turned out to be a bad solder joint on the bucket ram, a little twist and it came off, here it is after cleaning up:

http://i1252.photobucket.com/albums/...psgmgr1d15.jpg

Also broke a track link near the end of the day, so will order a few spares, I expected them to be a bit stronger than that:eek:

http://i1252.photobucket.com/albums/...pszmm0wtea.jpg

Cheers
Stu

Re: Liebherr 944B
 

i agree . awesome bit of kit.
mine is on the plane heading my way.

Re: Liebherr 944B
 

Cool! be interested to see what sounds you end up using.

Repaired the bucket ram and made a modification to the hydraulic lines:

http://i1252.photobucket.com/albums/...ps88zj7xxk.jpg

http://i1252.photobucket.com/albums/...psoaprrkkd.jpg

Back on track lol:

http://i1252.photobucket.com/albums/...psb0oqeqvj.jpg

cheers
Stu