3CX JCB 1997 Maintenance questions

Gecko

Gecko

Well-known member
Jumping on a banjo is one thing, but driving over it with those tracks just isn't sporting!

Has your machine got boom suspension?
I don't think so.
I can't see a mention in the service manual (and I don't have the operators manual)
 
Gecko

Gecko

Well-known member
this one is not too flash either

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Gecko

Gecko

Well-known member
Wondering about these seals disintegrating - Is this type of failure a normal sign of old age or does it suggest contamination / poor quality / something else?
 
V8Druid

V8Druid

do it as well as you can,but learn to do it better
Wondering about these seals disintegrating - Is this type of failure a normal sign of old age or does it suggest contamination / poor quality / something else?
I would put it down to age, constant immersion in oil, general use,wear and tear, etc. --- friction isn't kind ....and they don't last forever :rolleyes: :cry:
 
Gecko

Gecko

Well-known member
Thanks - that sounds like the 'least worst' cause.
I'm concerned that if the fluid is contaminated, all the seals will have to be replaced.

The fluid itself has that bitter "way overdue" smell to it, so it'll get changed soon, but I'd prefer to replace it after I've fixed the leaks / damaged seals.

On the subject of changing the hydraulic fluid, is it standard procedure to just dump the tank contents and refill or is some effort made to flush the fluid from the rams?
 
V8Druid

V8Druid

do it as well as you can,but learn to do it better
Thanks - that sounds like the 'least worst' cause.
I'm concerned that if the fluid is contaminated, all the seals will have to be replaced.

The fluid itself has that bitter "way overdue" smell to it, so it'll get changed soon, but I'd prefer to replace it after I've fixed the leaks / damaged seals.

On the subject of changing the hydraulic fluid, is it standard procedure to just dump the tank contents and refill or is some effort made to flush the fluid from the rams?
they're all likely to be the same age, but not necessarily in the same condition :unsure: ..... suck it and see'd be my approach TBH :rolleyes:
 
V8Druid

V8Druid

do it as well as you can,but learn to do it better
.......just dump the tank contents and refill or is some effort made to flush the fluid from the rams?
suppose you could drain the opposite strokes if you were really keen :unsure:...... close all cylinders ... connect a drain line to the full sides and cap off their feed lines and operate each in turn to purge the bulk from them, but there'll always be residue in the pipe work !!
you'd want to be exceptionally 'keen' to completely purge the entire system :rolleyes:
 
Gecko

Gecko

Well-known member
I was thinking more along the lines of a partial fill with the cheapest oil I can find - then cycling one cylinder/pair at a time.

I agree this shouldn't be necessary, but the smell suggests I want as much out as possible.
 
V8Druid

V8Druid

do it as well as you can,but learn to do it better
I was thinking more along the lines of a partial fill with the cheapest oil I can find - then cycling one cylinder/pair at a time.I agree this shouldn't be necessary, but the smell suggests I want as much out as possible.

I'd go with all closed, etc, as above ..... get a lot more out that way ..... boom first and drop the line at the king post, so you can get it back on easy .... then dipper - it'll be at G/L for a reconnect, then crowd .... if you have king post to the left, slewed left, can then do left slew cylinder (open) to atmosphere ... close off when empty and reverse the process .... that should get max possible oil out ...... extra dig last, now you have full use of services ... drop off the close line, etc and extend with new fresh oil ... and don't forget to keep topping up the reservoir ;)
 
Gecko

Gecko

Well-known member
I'd go with all closed, etc, as above .....
I can make that work.


I spent a solid week pampering this machine before flying out again.
Learnt quite a lot including how it had been treated in the past.
The top pin of the extradig ram had apparently seized at some time and the fix included a gouging torch and a stick welder.
It took a large drift and a sledge hammer to get the pin to move. I was a bit odd in that it was stiff all the way - the last person to put that pin in, knew what he was doing.
30 min of drifting got the ram free. At that point the truth became apparent. The last person to put it together had used a wholesale quantity of nickle anti-seize in the assembly. Clearly he knew what he was doing.
While it took a lot of effort to pull it apart, there was no scoring or corrosion. Given how bad it could have been, I think I got out of this one easy.

1571306723709.png


As you can see, one of the extradig lines had broken free and both of the steel feed pipe down to the bucket have broken their mounts (and been artistically bent while they were flapping around).
 
V8Druid

V8Druid

do it as well as you can,but learn to do it better
View attachment 9552

As you can see, one of the extradig lines had broken free and both of the steel feed pipe down to the bucket have broken their mounts (and been artistically bent while they were flapping around).
bloody hell ... that was drastic :oops: o_O ...... bet he wore a big stetson :rolleyes:🤣
 
Gecko

Gecko

Well-known member
I'll do a few more rams on my next trip to Oz.
The second stabiliser has an internal leak and drags it's foot after 5~10 min
I've come to the conclusion the shovel dropping is due to an internal leak of one or both of the lift rams. I'll replace both sides and see what it looks like inside.

The fun job will be replacing the wear strips on the extra-dig. These have clearly been absent for some time running metal on metal - hopefully the wear won't cause a problem.

I assume the procedure is to fit the lower pads (as retracted as possible).
Insert the lower dipper and then position the upper pads.

Any suggestions or advice on this fun job? 🤪
 
Gecko

Gecko

Well-known member
- I was assured it was fitted with a half hitch. Imagine my surprise when the high pressure cleaner exposed a hydraulic quick hitch. Unfortunately, there is no plumbing, so swapping buckets will be interesting.
Been looking for options to solve this little problem when a genuine JCB quickhitch kit appeared on fleabay for a suspiciously good price.
The part number looks like a full kit, but the price is so good I feel I'm failing to see the obvious.

I contacted the seller and just got a "it's in the warehouse / can't check / last one" answer which left me more suspicious rather than less.

Hoping fleabay will take my side if it turns out to be "not as described", I ordered it last friday. Given I was explicitly told "it's the last one", I was surprised to see another listed today.

I'll report back when it arrives.
Until then, there is at least one more available at what I hope is an unmissable price.


1572348709783.png
 
V8Druid

V8Druid

do it as well as you can,but learn to do it better
Hoping fleabay will take my side if it turns out to be "not as described", I ordered it last friday. Given I was explicitly told "it's the last one", I


View attachment 9739
more chance of getting a roast pork dinner with the pope and Robert Redford in a synagogue .... they're to**ers
 
V8Druid

V8Druid

do it as well as you can,but learn to do it better
Hopefully I won't have to test that!
I'd be happy to settle for the 'quickhitch kit' as described
see there's a lot of this stuff advertised in N. America ... bit more bucks though, but not huge amounts ... certainly cheaper than any prices in the country they're made in :unsure::mad:
 
Gecko

Gecko

Well-known member
The seller is clearly a bulk handler of distressed/liquidated/clearance stock of which they know little and care less.
They didn't offer a photo, only the part number. If they can get that right, I've got a great deal!
It'll arrive in a week and I'll discover if I've had a win.
 
V8Druid

V8Druid

do it as well as you can,but learn to do it better
The seller is clearly a bulk handler of distressed/liquidated/clearance stock of which they know little and care less.
They didn't offer a photo, only the part number. If they can get that right, I've got a great deal!
It'll arrive in a week and I'll discover if I've had a win.
from what I can see elsewhere, that part number is simply the rubbery bits .. no QH Valve :(:unsure: ....... but you may be fortunate enough to find one lurking on said Jake if you're lucky ... it's got the hitch ... you never know, might once have been connected ??
 
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