Just purchased a used Volvo mini-excavator and have put 30 hrs on it and have a few questions being new to heavy equipment. I have been greasing the zerks every 10-15 hrs that I can find but other then the track tension, I can't find anywhere to lube the track rollers/ sprocket and they are getting noisy. Is there a need to lube these parts or is it just a matter of blasting them off with a hose to keep them free of dirt and squeaks? Also, when engaging the high speed (haha) the excavator doesn't travel any faster but there is a change of sound in the drive motors for the tracks. Could this be an issue with the drive motor or possibly hydraulics? How do you properly check the hydraulic oil/ oil level etc. Unfortunately I have not acquired a manual yet (back ordered) so I am blind to possibilities for this issue. Any thoughts are appreciated
There are no lube points for the rollers. They are sealed bearing. I grease everything daily except the turn table. That gets about 3-4 pumps a week. I was told that's probably to much
Thanks. Will be getting running water on my property next week so I will hose off the tracks and rollers and see if it gets the squeaks out. Any feedback on the final drive 'moaning' when I engage the high speed feature? So tiered of traveling slower then walking speed ...
Check the hyd oil level with the machine on level ground, engine running with all the cylinders extended (boom up,arm in, bucket curled in, blade down). The level should be in the middle of the sight glass. To check travel with Hyd oil at operating temp lift the machine off the ground with the blade and the bucket. Run the tracks in both directions. Mark each track and measure the time it takes to make 3 revolutions (run for minimum of 1 revolution before starting). Do this in forward and reverse high and low speed for both tracks. Time should be 26+ -2 sec for low and 15+ -2 sec in low. You can also check the travel gearbox oil level while in the air.
Thanks Ben. Great reply! I will check these things next week when I get to my machine. When you say 'check travel box oil level' is it fair to assume you mean the final drive? Any idea what format is used to open the access ports to view the oil level? Alan Key or socket? I don't have a manual ... yet.
When you open your hood to access the sight glass , there should be an illustration. It should show bucket curled all the way in, arm fully extended, on level ground. Engine off.
If memory serves me the sight glass was under the seat in the cab and it is beige tinted with a diamond shape black line as part of the sight glass which itself was round, about 2" diametre ... So now is it engine running or not? Boom extended or pulled in tight?
Yes final drive. It should be a metric allen plug in the center of the cover. This is the position for checking hyd oil level. This is the location of the sight glass on the hyd tank
In case it is related, I should also mention that if I lift the tracks off the ground with the boom and wait 5-10 minutes the machine will slowly creep back down to the ground. The same is true if I leave the bucket off the ground with a raised boom, the bucket will lower to the ground also over a few minutes. This became obvious while changing a track a few weeks ago. I had to keep lifting the machine every 5 minutes or so during the process. Thanks again for the input.
There is an allowable amount of drift for the hydraulic cylinders.
I checked the sight glass as instructed above with the machine warm - both running and off and the oil is exactly mid way in the sight glass. I assume this is the proper level for it?
Yes that is correct. Did you measure the track speeds?
No. I did try it on flat ground and the Rabbit Speed button made some difference. I can definitely hear a difference, like something is working harder. Low moan sound. Maybe normal? Just final drives working harder? It gets to a moderate walking speed at 3/4 throttle I'll try and remember to check next weekend using your suggested method.
Whoa! For starters, full throttle at all times. Throttle isn't like a car, where if one wants to go faster, they use the throttle. Need pump working at full power. Use hydraulics levers to control speed, not throttle. Second, check your drive motors for oil (on drive motors, there are usually two allen/torx screws...one to drain, and one to fill - have one at 6 o'clock and the other at 9 o'clock, then check 9 o'clock to see oil level - in other words, gear case on drive motor should be half full of oil). Given what you've said, I would come to a FULL STOP , and check drive motors before I moved another inch. One might get a slight pitch change, but a low moan doesn't sound good. And, you should be tooling along twice as fast in rabbit mode over normal mode. First thing with a new machine is change the drive motor oil, as they are expensive to replace, and the number 1 failure is because the gear case ran dry (seals went). Everybody seems to ignore or forget them...
@melli I have checked the track speed rate while the machine is lifted and the rabbit speed is about double that of normal. Once there is a load (slight uphill grade) there is no difference in the speed of the machine. On a higher grade the slow speed still moves the machine while rabbit just moans. It only seems to track faster when going on a downhill grade in rabbit mode. RE: Idle ... I read through a thread on this forum on where operators keep their idle while working and the answers were so all over the place that it resulted in a 10 page flame war, so the question was never really answered. To each their own or depending on the work demand was the decision. So that's what I've been going with. I'll check final drive oil before I use machine next. Any suggestion on oil that should be used in them?
Just wanted to mention don't overtighten your tracks that can cause them to turn slow and more importantly stress All your undercarriage components
Manual will say what gear oil to use (usually 80w-90 or higher). Sounds like you have an issue with rabbit mode. I'd open cover plate on inside to see you have no leaks. If the gear case looks ok (full of oil, no flakes etc in oil), then it is something to do with hydraulic side. Since you can get rabbit speed without load, electrical is probably ok (mine has solenoid). Flame war over rpm speed? Odd. Call your dealer then, don't listen to us. I bet he'll say full throttle, which is only about 2500-2700rpm in most machines. Full speed keeps pump at full pressure so all implements work properly. It also keeps cooling at max.
Thanks @melli I am new to all things heavy equipment so I am not doubting your advice on throttle. Just trying to gather and process info as I get it. I have had occasional problems with cooling after a couple hours use but topped up coolant and haven't since. Maybe it had more to do with using the machine at low rpm?? I'll take your advice and check oil in final drives etc. I ordered a Tradebit E-manual but cannot find info on specific fluids. May be missing as manual seems half ass in its layout. Thanks
No worries, but I've never seen an entry in manual to put throttle at half etc. And all the pro excavator drivers in my hood are always on full throttle. Heating is due to low coolant as you noted, but the biggest issue I've experienced and read on these boards is making sure radiators are CLEAN. In a dusty environment, the rads clog up (on outside) quickly. And these small machines, like mine, have three rads sandwiched together (engine, hydraulic, AC). Plus, it is really hard to clean them effectively...and to even see how dirty they are without pulling out the wrenches to pry them apart an inch or so. Also, having a clean air filter helps too... Mine is prone to overheating I suspect because of design. The body is heavy 3/16-1/4" metal jacket with few air vents. I'll bring machine to idle, with hydraulics disengaged, open engine and hydraulic lid, and let it cool for a few minutes...temps come right down, and I am good to go for another hour. If super hot outside, I don't even bother...I don't have anything mission critical that can't wait for a cooler day. Also noticed using the right hydraulic oil makes a difference in temps...a heavy oil can heat things up.
The finals take either 80W90 or 85W140 gear lube. 85W140 is not meant to be used below 35F. You can run the throttle anywhere you like but I would recommend keeping it above 1400 rpm to keep from overloading the engine. Real operators do not need to run the machine at full throttle. You are only making noise and wasting fuel doing so. They are best run a few hundred below full throttle just above peak torque. Volvo recommends running them at or near that speed. Hydraulic oil should be ISO46 in most cases. The machine will slow down when traveling up a grade. When pressure rises it will shift the travel motors back to low speed to maintain travel instead of just stalling out. Have you measured the track speeds with a stop watch yet? Do you have access to hydraulic gauges to check pressures when traveling?
Hi BucketList, I think think the optimum engine rpm changes depending on machine size and engine. On my machine is only small with 3 cylinder motor and has digital display so is easy to set rpm. I think mine goes from about 1200rpm to 2600rpm. I generally run around 1800rpm and the reasons are as follows When you look up the torque curve for my motor it develops maximum torque at around that speed and like Ben Witter said if the pump throws full load on the motor it has the rpm to deal with it. Even though i have a target speed if you vari the rpm a little you will still find there is a sweet spot you can find where the vibration is reduced. I find the noise level is lower and fuel is better and the speed of the machine is fast enough for my old brain. I will put the speed up high if i am pushing the machine to do something big but usually come back to my normal speed again when finished. The operating Manual on mine says the longevity of the machine will be increased if you can keep the rpms down so read between the lines i think. Cheers
I see this is turning into a RPM thread...haha. The machines WOT is set to produce max hydraulic flow and pressure, not to find the engine's torque curve. The engine's torque curve is, generally speaking, immaterial. The hydraulic pump drives the machine, and the engine WOT is set to give the pump max effect. Plus, cooling comes into play if your at half WOT, for example, and doing some digging. Nowadays, newer machines have load sensing, and will automatically adjust RPM. They will go to idle if you stop (i.e. stop putting a load on hydraulics). Then when yous start moving again, WOT. Plus, these engines are not running at 'true' WOT. They have been down-rated for longevity. WOT has been set on your machine for a reason, to give you max power without stressing engine (overheating). It depends on age of machine, but an older machine like mine, has an oversized engine relative to today's model, which have to comply with Tier 4 emissions. So, to make an engine compliant, they went with a smaller engine, in addition to cleaner burning engines. But, they wanted the same power. Obviously, all things being equal, a smaller engine outputting same torque as larger engine, will not last as long as a bigger engine. What to do...put in load sensing, so the engine can take a break (go to idle more often). This helps make an engine last longer (an engine at idle), plus reduces emissions. As I suggested, get a manual or call your dealer.