JCB 8018 Retracting Blade

[Wee Jim]

I have a JCB 8018 which is a great little digger. Its a 2005 with 1235 hours on the clock. The problem i have is that when i have the blade down for support if i hook a large stone or something and pivot on the blade as you do the blade retracts so you have to put it down again for stability. I have since discovered that if i turn the switch on that changes the blade lever from working the blade to opening and closing the retractable tracks the blade will stay solid. Has anyone else had this problem and know what it may be??

[ianoz]

Hi W Jim ,I am no expert , but i would say the conrol valve is the problem . If you use the same control valve to work the blade and the track retraction , when you switch to track retraction ,a diverter valve will lock off the blade fucntion..So it should not move . I would say relief valve on that funtion is set to low .
Don't worry about your spelling , We are all crapppy spellers here.

[Muz]

The relief valve is probably correct for the dual purpose it serves, ... since when was ballet dancing on the dozer blade good operator practice ?

You could adjust the valve up a bit, but being a jcb ... it will cover atleast two other services, probably your left and right tracks, and possibly even the slew. This will end up allowing too much pressure to the drive motors, and may give extra traction etc, but more likely start blowing hoses on 'all' the circuits.

The key to this is as follows, if your tracking power is ok .. leave well alone (assuming its the same relief which it normally is) if you find it wont sprag on concrete or tar, then the pressure is too low and needs to be adjusted.

However .. the pump may not be able to deliver that pressure, and it may be that , which is at fault .. but then you would notice other services weak aswell. You'll need a work shop manual and a guage put 'inline' somewhere to test that the 'blow off' pressures are correct to be certain

[JD450A]

your problem is caused by the fact you have a JCB 8018... Horrible machines though fast on the slew.

does your machine have the stupid clip on blade extensions?

[Wee Jim]

your problem is caused by the fact you have a JCB 8018... Horrible machines though fast on the slew.

does your machine have the stupid clip on blade extensions?

I reckon the JCB to be a very good little slew. i have driven other and fouund them poor compared to the JCB.

Yeah it has the blade extensions. Cant fault them either tbh!!

[JD450A]

I disliked those extensions, seemed very easy to loose on self drive and with them not being bolted to the machine the cutting edges on the actual blades wore. Much prefer takeuchis bolt ons or better still bobcats Pinny slide out things :D

Agreed on the slew, Nice, fast, Powerful. Aside from that I can't say I'm a fan.

[Wee Jim]

I had ScotJcb round today looking at my digger and John the mechanic reckons the fault is an ARV i presume that means auto return valve am i correct?? The blade went down at a good speed but has always been slow in coming back up. So fingers crossed it will be sorted soon.

[Muz]

You should have told him to smile for the camera .. then he would have been famous across the world !!

[Wee Jim]

You should have told him to smile for the camera .. then he would have been famous across the world !!

He was working on my money so he didnt have time to smile!! I bet the bill wont be cheap!!

[245dlc]

Never is when you have to call the dealer, hope your able to get it sorted Jim.

[Wee Jim]

the good hing is that its still working i just want it to be working correctly. It also turns out that i am missing the slew lock for mine. I thought that mine just never had one but the mechanic said it should have it so for £45 i'll fit another as its real handy for locking the slew when working next to a house or when on the trailer.

[andy jcb]

I have a JCB 8018 which is a great little digger. Its a 2005 with 1235 hours on the clock. The problem i have is that when i have the blade down for support if i hook a large stone or something and pivot on the blade as you do the blade retracts so you have to put it down again for stability. I have since discovered that if i turn the switch on that changes the blade lever from working the blade to opening and closing the retractable tracks the blade will stay solid. Has anyone else had this problem and know what it may be??

The auxiliary relief valve should be set at 220 bar for dozer and track extend and the best way to test is to tee in between the RAM pipe and its hose with a gauge then power the dozer ram down to see the arv relief pressure. If not then your dealer should have the correct hydraulic hand pump to back feed at the same union on the dozer ram extend hose and gently pressurise the circuit to the valve block slice this will allow adjustment of the arv. This is the easiest, quickest and safest way. Happy diggin'

[Wee Jim]

The auxiliary relief valve should be set at 220 bar for dozer and track extend and the best way to test is to tee in between the RAM pipe and its hose with a gauge then power the dozer ram down to see the arv relief pressure. If not then your dealer should have the correct hydraulic hand pump to back feed at the same union on the dozer ram extend hose and gently pressurise the circuit to the valve block slice this will allow adjustment of the arv. This is the easiest, quickest and safest way. Happy diggin'

Cheers any. I have now got it sorted. JCB fitted an new valve and she is working like normal now.

[Garry]

Case in point when I read this thread,dont these guys put test points into their circuits yet ? ....... you still have to actually break into a line ?