The Classic Machinery Network

Hi all - new to the forum and my first dumper! I've always wanted one, and now I can justify it as I have quite a bit of earth moving to do in constructing an extension and new shed.

Would be really grateful if anyone can help identify the make, model and likely date of manufacture. I think it's a Thwaites and I'm pretty certain it's a 3 ton.

It has a 3 cylinder Lister or Petter marked PJ3 on a plate on the engine.

Does anyone know where the chassis number might be located?

The wheel arches built into the skip are quite distinctive I think.

It seems to be in pretty good order, but desperate for a good service (not least because someone has filled the hydraulic tank with diesel!)

Any help gratefully received. Cheers, Matt.

Welcome Matt

Certainly looks just like these ones on ebay listed as a Thwaites: Thwaites 3 Ton 4x4 and Vintage Thwaites

Bit of rooting around and I found mention of a similar machine on Nick Drew's 'Diggerman' blog as pictured by Jeremy Rowland: Twaites Alldrive 3 Ton

Both of them post on here so they might spot this at somepoint and add a bit more detail

Hi,
I ran one of those for several years, It is certainly a Thwaites 3 ton machine. We had excellent service from ours in very demanding conditions,
I hope you have as much luck with yours.
Pictured below, at work with a Priestman Mini Mustang.



Just a thought, a bit more useless info. The Petter PJ series engines were in production when Hawker Siddely took over Lister Petter and some were badged Armstrong Siddely.
I worked on one A-S PJ4 in a generator and an A-S PJ2 in an Air Pumps compressor.
Air Pumps compressors were a product of Armstrong Whitworth.

Thanks do much fo the info. It definitely looks like the same machine as in the image above and in the interesting blog. Only difference I can see is the rear wheel arches, which are flat on mine. But it's definitely the same machine. I am missing the panel with "Thwaites" on the back.

The engine seems to have no oil filter - does that sound right?

singlemalt wrote:The engine seems to have no oil filter - does that sound right?

Err...no! It might have an old school replaceable filter element in a housing rather than a spin on all in one canister type.

In Ronan's thread where he was looking to identify his machine which turned out to be the same as ours (a Thwaites Nimline) he mentioned this chap as a Thwaites guru: http://www.davidcornwallis.com/

You might be able to find a manual on his site for your engine, and even references to the parts (but not prices). The engine is bound to be a fairly common unit shared with a variety of different machines and manufacturers so parts should be plentiful once you have identified the unit that you have. I mean the oil filter element in our very early Thwaites machine was so common and used in so many different engines that our local motor factor had one on the shelf! Mind you the guy there is a bit of a legend he saw the remains of the old filter and the housing and went: 'Oh that's off a Thwaites Nimline Petter engine, here...' and proceeded to go straight to it!

Oil filter.

Err... Yes !!
But not as such.
Remove the crank case side panel and there is a washable strainer. It's attached to the oil pump inlet with a jubilee type clip. Just wash and replace.
No disposable filter element was fitted.
Fred

Yikes, the same filtration system as chainsaws and finest Chinesium small capacity singles...whod've thunk that a later build, multi-cylinder engine (probably derived from the same family of engines as the single in our Nimline) would use a more basic filtration system

Thanks very much for all the help here. I'll look for that removable panel on the crank case.....doesn't look immediately obvious - can you remember if it was on the fuel pump side or the other side?

I've got in all replacement oils and filters ready for a complete fluid change - I doubt it's had one for years!

Hello again Matt,

I should have said that some of the PJ engines were fitted with full flow filters in an external canister as an option, so you may have been supplied with a filter element in error.
My dumper didn't have one and if as you say you can't see an external filter canister, (which would be quite obvious), yours will be the same.

Fred

P.S. The crank case inspection covers will be opposite side to the injector pumps as would the filter canister if fitted.