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Sabre

300TDi overhaul

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A good assembly lube helps too:

https://www.eurocarparts.com/ecp/p/car-accessories/engine-oils-and-car-fluids/auxiliary-fluids/specialist-fluids/?522773492&0&cc5_871&gclid=CjwKCAiAqbvTBRAPEiwANEkyCMbawrHXOvU0m8W8Qx3LhNFsDE_F7S-pzLWD-RX_EK5jmUG9eIN5YBoCD2cQAvD_BwE

Lots of sticktivity and film strength to provide protection long enough for oil pressure to build up. I also tend to do exactly as Western describes and run up on the starter. 

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So, I started stripping the engine, and I am now sure that the oil pump failed. Looking at the pump's location on the crankshaft, I have to ask what drives the oil pump ? No key/location slot in that area. If it is the pressure from the tightening of the crank bolt, the bolt was definitely not loose, took the usual amount of levers to loosen 

What would cause the damage to the crank and the pump ?

Is the crank salvageable ?

New oil pump bought already 

I found small pieces of rubber in the sump, difficult to identify, but it might be be small pieces of an oil seal. I have not had a close look at the seals yet

Crankshaft 1.jpg

Crankshaft 2.jpg

Oil pump.jpg

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1 hour ago, Sabre said:

So, I started stripping the engine, and I am now sure that the oil pump failed. Looking at the pump's location on the crankshaft, I have to ask what drives the oil pump ? No key/location slot in that area. If it is the pressure from the tightening of the crank bolt, the bolt was definitely not loose, took the usual amount of levers to loosen 

What would cause the damage to the crank and the pump ?

Is the crank salvageable ?

New oil pump bought already 

I found small pieces of rubber in the sump, difficult to identify, but it might be be small pieces of an oil seal. I have not had a close look at the seals yet

Crankshaft 1.jpg

Crankshaft 2.jpg

Oil pump.jpg

This is exactly what I was talking about! A stupid design, and by no means an upgrade to the previous design (<200TDI) :(

Ideally you would change the crank but I suppose it could be welded up and ground smooth by a pro, and then you could fit a new gear and it would be as "good" as new

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It looks to me like they're relying on friction drive, and the flats are a sort of last resort/location. The bolt may have been tight, but was it tight enough? 

Is the advice in the manual to change the bolt every time its removed? If so, they're stretch bolts - "torque to yield" - and will not provide the full clamping force if reused. A possible scenario... A quick Google days 80Nm, then a further 90°, which is pretty typical of stretch bolts. 

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The inner rotor of the pump is supposed to have flats on it that match the crank.

 

 

 

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7 hours ago, lo-fi said:

It looks to me like they're relying on friction drive, and the flats are a sort of last resort/location. The bolt may have been tight, but was it tight enough? 

Is the advice in the manual to change the bolt every time its removed? If so, they're stretch bolts - "torque to yield" - and will not provide the full clamping force if reused. A possible scenario... A quick Google days 80Nm, then a further 90°, which is pretty typical of stretch bolts. 

What you are implyinjg is very likely, but IIRC when I took mine apart I thought the same but couldn't find any evidence that this was the design, as you can see on the pics the machined part of the crank is much wider the the gear so there is no way to hold it clamped. I suppose that the idea is that as soon as the oil pressure is achieved the drag will keep it to one side of the flats and then that's good enough. The Wear probably happens at startup where it Rattles from side to side until oil presuure is achived. At least thats my thoughts on the subject :) 

7 hours ago, Red90 said:

The inner rotor of the pump is supposed to have flats on it that match the crank.

 

 

 

As you can see on Sabre's pics these flat parts have been worn down. Even when both parts are new it is a rather loose fit

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I unpacked the new oil pump and it is now clear to me how the pump is driven. The 2 elevated slots in the rotor slide over the edges machined on the crankshaft, and is therefore driven by the crankshaft. The crank pulley bolt plays no part in this

Looking at my picture of the rotor, it is clear that the elevated slots and the crank edges, wore each other down. That is why the inside of the old rotor appears relatively "smooth" (No elevated slots)

Question now is WHY ?

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I'd still argue its down to it rocking back and forth because it isn't held in place by anything, as I posted previously

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The cover plate that encloses the oil pump sits pretty close to the stator & rotor, so close that there are rubbing marks on it. So I agree that there is no other device that stops lateral movement than the plate. But that movement is minimal

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its not the lateral movement I'm reffing to. Its the rotational rocking back and forth of the inner pump wheel on the crank because there are essentially only two points of contact and they are not a snug fit. Sorry my limited English vocabulary isn't enough to explain it better :( 

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Thanks Soren, I agree with your explanation

(My mother tongue is also not English, and I understand you perfectly :)

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Yes, lots of really crappy designs in the 300TDI.  Oil pump, water pump and vacuum pump are all failure points.  Two steps forward and three back when they designed the engine.

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On 2/20/2018 at 9:32 PM, Red90 said:

Yes, lots of really crappy designs in the 300TDI.  Oil pump, water pump and vacuum pump are all failure points.  Two steps forward and three back when they designed the engine.

Those items were probably designed by a committee....... :angry:

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If I ever meet the designer of the 300 TDi, I would like to ask him how on earth do you remove the top bellhousing bolt in a Discovery 1?

Seeing that I will probably never get the opportunity, are there any special tools/tips from the informed on this format ?

I got it out, but will suffer for days to come from back ache; what a schlep !

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Loosen the gearbox mounts.  Lift the engine and remove the engine mount rubbers.  Drop the engine down without the rubbers.  You will then have a lot better access to the upper bellhousing bolts.

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Thanks Red, good info !

By how much can one drop the engine with the aircon and diesel pipes still connected ?

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Those lines should not matter.  the exhaust needs to be disconnected.

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Top bellhousing bolts not given me any issues in a 300 disco, i go in through the top. Always forget to refit it though for some reason.

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Next question : The cylinders show their age, and have distinct ridges. How do I now remove the pistons, the top compression ring seems to get stuck at the ridge ?

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Handle of a hammer from underneath...

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Thanks B69. I take it that I need to hit against gudgeon pin then ?

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Inside of the big end :)

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Pistons can go out the bottom if the crank and oil jets are removed. Wooden handle on a mallet will do the job.

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