I keep tropical fish, in me underpants.... Digger pictures! Engine rebuild

[drum]

The radiator and its housing came out ok, then that shaft from the crank to the hydraulic pump was muscled out.

 

Two bolts are all that attach the front of the engine to the cradle it sits on.

 

The gearbox end is more awkward.

 

A floor plate in the cab unbolts and lifts with the gear stick allowing access to the top of the gearbox and bell housing.

 

 

I've removed the inspection cover in the piic.

 

The bell housing splits horizontally with the top half held on with 10 tight as f@ck bolts.

 

The digger weighs about 8 tons and I think 7 of them are in the cast iron bell housing cover. It took a while for me to manoeuvre it through the hole in the cab floor what with brake and clutch cables in the way and the fact it has the same mass as a small planet.

 

 

Pins removed from the drive shaft sleeve but it's not keen to slide forward.

 

Next time I'm home in daylight I'll try and finish getting the engine out.

Just need to figure out how much of this clutch mechanism I need to take apart.

[drum]

It's Sunday which means up at 7.45am for digger fettling.

 

I had to get a few proper* jobs out of the way first, so by 10am I was ready for oily hands.

 

I planned on lifting the engine out today so disconnected the remaining wires, cables and hoses meaning all* I had to do was lift it out.

 

The loader on the davie broon was going to do the heavy work, only the bastard thing wouldn't start.

 

Click click rattle went the starter motor. Farted about checking connections, changing the battery, jump leads blah fucken blah.

 

Wrestled the starter off which is a pain as the loader frame is in the way. I'd replaced the solenoid less than a year ago with a cheap ebayism.

 

It was clicking and rattling on the bench but started working properly after I cleaned the plunger and associated internal gubbins.

 

Wrestled it back on the DB and it fired up. Might sound quick and easy but it wasn't and it was now 3pm and getting dark.

 

Swung the DB over the hymac's engine only to find I was going to have to completely remove the digger's bonnet, as it was going to foul the bucket on the DB. It's hinged on two bolts at the front. Two rusted-to-fuck bolts, one of which I had to give up on with the spanners and take the angle grinder to.

 

I'd stopped the DB while i was removing the bonnet and now the starter motor was back to its old tricks.

 

I'd suspected it might do this so had parked it facing down the hill. Took a bit of jumping up and down on the back wheels to get it to set off. Not a recommended procedure and a bit hairy trying to get back on the seat while it takes off down the hill. Fortunately it started at the first drop of the clutch.

 

Back to the engine removal which should be simple now, yes?

 

Was it fuck.

There's a frame round the engine that the radiator and hydraulic filter and pump attach to, making it really awkward to get the engine out. It had to go up 6 inches then forward 6 inches then up again with fuel pumps, steering pumps and filters to get snagged on that frame. A pus-ache when you're on your own.

 

Finally, at 7.30pm I set it down on a temporary stand.

 

If the garden hose isn't frozen tomorrow I'll give it a powerwash.

 

TL:DR

 

I took the engine out. It was a ball-ache.

 

 

One the fan blades got bent in the process.

[somewhatfoolish]

I haz digger envy.

[N Dentressangle]

So what's the working diagnosis on the lump?

 

I'm guessing that's some kind of a magnet thing with some ball bearings attached in your pic, which must have come from somewhere specific.

 

Parts look pricey:

 

https://www.tractorspareparts.co.uk/leyland-engine-parts-leyland-498-diesel-engine-c-18_845.html

 

or is there a more modern, cheaper engine that'll fit?

[drum]

The source of the ball bearings will be revealed when I remove the timing cover off the front.

 

I'm hoping not to have to spend too much on it. Don't think it has been well maintained in its previous life, like a dude that's smoked 40 JPS everyday, it has lost a bit off its punch. A bit tired and wheezy.

 

Might get away with new piston rings, gaskets etc. If it's totally shagged, I know someone with a replacement engine for not too much coin.

[drum]

I know you've all* been on tenterhooks waiting to find out where the ball bearings came from

 

Crankshaft nut and pulley off first.

 

 

Timing cover off

 

And...

 

it's the steering pump idler gear bearing that's got no balls.

[somewhatfoolish]

[Guest Hooli]

 

Looks like a seal of approval for the thread.

[D Spares & Tyres]

Great thread. I would love an old digger. I have no use for one though.

[Rocket88]

Great thread. I would love an old digger. I have no use for one though.

 

Since when has that been an Autoshite consideration?

[somewhatfoolish]

And...

 

it's the steering pump idler gear bearing that's got no balls.

That's reminiscent of the time I rebuilt the gearbox off my Royal Enfield and discovered the contents of one of the layshaft bearings in a layer of what could only be leftover casting sand at the bottom of the casing.

[N Dentressangle]

Brilliant. That thing looks like it was designed to survive a direct hit from the Bismarck.

 

https://www.tractorspareparts.co.uk/amk1535-idler-gear-bearing-p-1082.html

 

Amazing you can still get the bits, too, and for not too much cash.

[DodgeRover]

Are you planning on dropping the sump while you are at it to remove anymore stray balls?

Rings and shells while it's in pieces?

[drum]

That's the plan. Hopefully the liners are ok otherwise it starts to get expensive.

 

I need to check the seals on the CAV pump as not only does it drip on the outside, I suspect it's leaking diesel into the sump.

[bigstraight6]

Brilliant stuff, I do like a bit of old plant machine action..

[DodgeRover]

That's the plan. Hopefully the liners are ok otherwise it starts to get expensive.

 

I need to check the seals on the CAV pump as not only does it drip on the outside, I suspect it's leaking diesel into the sump.

That's usually the lift pump filling the sump with fuel.

[Dan_ZTT]

Just seeing this thread for the first time, awesome stuff. Much digger envy, even if it's broken.

[drum]

Manhandled the engine into the garage.

 

I got another idler gear with bearing FOC so put that in. Timing cover needs a new gasket but that can wait until I decide what I'm doing with this lump.

 

Took the rocker cover off and noticed one rocker was lying on its back, clearly not in the mood for opening valves.

 

Closer look revealed the damage.

Bent and broken

 

I don't know how this can happen.

[drum]

Took the head off for a looksee.

 

Bit of damage on the gasket between 3rd and 4th bores.

 

 

Popped it on its side and took the sump off

[drum]

Took a cap off and had a look at one of the main bearings.

It isn't good.

Badly scored but also the edge is chewed up. Bits of bearing flaking off.

 

The crank shaft is marked and probably should be reground

 

Big end bearings are also badly needing replaced.

 

 

Pulled a piston out. The rings are intact but check out the scratches on the side.

 

Carbon build up on the top of the piston.

 

The liner.

 

I assume thin oil has caused all this damage although the bent rocker I don't understand - timing out?

 

Decision time now. To do the job right I would need to get the crankshaft reground, new piston and liners, new bearings etc.

 

Could I get away with just replacing the bearings and sorting the rocker, or will I never get oil pressure with that crankshaft?

[PhilA]

Bearings look like they've suffered low speed, low oil pressure, high load damage from sloppy endfloat- fatigue flaking there showing that. Peel up a flake carefully with the tip of a blade and inspect. Is it discolored? If not then it's not oil starvation, just really diluted and dirty oil causing the bearings to hammer by looks of it.

So long as the crank isn't badly oval you may get away with just sticking new bearings in if it's only going to see light use and regular maintenance.

 

My concern would be with foreign debris in the oil galleries at this point in time, how bad does the oil filter element material look and does it glitter?

 

Also rocker damage like that looks like the timing jumped. Inspect for damage to the teeth and or surrounding shaft area from loose balls.

 

Phil

[drum]

I wondered about end float, so new thrust washers needed too.

 

The smell off the engine is quite intense. Burst oil presumably. It's got the whole house stinking this morning which is not going down well with the rest of the family. Going to have to seal the garage door to the house or drag the engine back outside.

[John F]

Oof. That's a big job for early January in Scotland. Much kudos for taking it on.

 

Fingers crossed for you.

[drum]

Cheers! It's minus 6 here this morning.

 

I've been looking at vids on how to roll out the main bearings without removing the crank. Doesn't look too bad.

 

Think I'll go for the quickest, cheapest repair, so bearings and rings, thickest oil on the market and see what happens. I'll flush oil through and change the filter again to see if I can get all the swarf out.

[N Dentressangle]

Sounds like a sensible plan.

 

At the very least that should buy you a few dozen more hours of work from it, and that might last you quite a while. On the other hand, in a low-stressed, heavily engineered thing like that it might go on for ever!

[drum]

Took the other pistons out and found bad news.

 

One pair of big end shells has spun.

The two halves have practically welded together and not much left of them.

The journal on the crankshaft is badly scored, not surprising, so my plan to only change the bearings might be up in smoke.

 

Any mileage in trying to polish them up with wet and dry? Probably miles off round anyway.

 

Piston 1 was not keen to come out. Check out the state of it.

 

That ring won't be coming out in one piece.

This is the bore with the broken rocker.

 

What happens when one valve doesn't open. Will it not run or only run on 3 cylinders? It died on me while running so maybe the timing jumped and the rocker broke at that time, or can it keep going in this state?

[coalnotdole]

Personally I'd get the crank polished/ground as needed. New liners are only about £30 each or I expect someone does a piston/liner combo deal fairly cheap as they're a common tractor engine. Also worth checking the state of the oil pump internals as its probably had a life of crap oil and sludge being run through it.

 

The damage to the piston skirts looks a lot like what i'd expect to see from an engine that had heat seized.

 

Guess it depends if you think chucking £400 odd at parts and machining is worth it?

 

Otherwise you might get away with lobbing a new set of rings and bearings in there and changing the bent rocker arm but your still going to have spent £150 and have no guarantee its not going to grenade itself again.

 

Dave

[drum]

Pricing up piston and liner kit plus shells and gaskets is getting on for £600 with the shaft machining on top so it's decision time.

 

The digger itself will never be worth much as the tin worm has had a belly full. I suppose the rebuilt engine will have a resale value once I'm finished using it.

[coalnotdole]

About £360 for an "overhaul" kit from the tractor dealers I think? (pistons, liners, rings, small end bushes, seals gaskets etc) then about 25 quid for each set of bearings?

 

Also I seem to remember the 4/98 was used by thorneycroft in marine applications and was very picky about thermostats - I think the originals have a disc on the bottom that closes off the bypass as the stat opens. supposedly fitting a normal/modern type thermostat without the disc can cause localised overheating as can leaving the stat out altogether.

 

Dave

[DodgeRover]

Is this the one?

https://www.tractorspareparts.co.uk/498-nt-nv-dt-dv-engine-kit-5-ring-piston-98mm-p-548.html

 

Cheaper here

https://www.agrilineproducts.com/engine-overhaul-kit-4-98-engine-218mm-liner-5-ring.html

 

Did you say it had been filling the sump with diesel?