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Boydie

Engine Rebuild & Blueprinting

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To keep me amused during the coming winter months (to us in Oz thats any temperature below 10 degrees C) I am in the process of rebuilding a 300TDi. Once built it will go into my Disco and I'll sell the incumbant - 370,000 kilometers - to recover some of the costs.

At the moment the crank is off being nitrided, it has already been X-rayed and has no cracks or defects, the nitriding process hardens the surface and makes the whole crank more durable, once that has been done the jurnals will be reground to suit new main and big end bearings. Once this is done the entire crank, flex plate and main pulley will be ballanced to spin at 12000 rmp, well over the expected maximum of 4000 so it should spin very sweetly.

Currently the block has been stripped down and the welsh plugs removed, the water ways were shot blasted with glass beads and some 1/2 a cup of foundry sand removed (and this from a 1999 engine that has done over 400,000 kilometres!) the block was then immersed in a chemical bath to totally remove every last vestige of paint and grease and its now in the process of being repainted - in BMC spruse green - mainly because I have a couple of tins over from doing up a Cooper S motor some years back!

The next step will be to have it sleaved and rebored back to standard, currently its 0.090" oversize. The conrods will then be checked to make sure that they are all exactly the same lenght and if not then stretched to match the longest one before being ballanced - all equal to teh lightest rod. The new pistons will be checked to ensure that the volume of teh combustion chambers are all equal, if not then the smaller will be polised out to equal that of the largest volume before they too are measured for length from gudgeon pin to crown, again, some lapping may be required to ensure they are all the same length. Land Rover are fairly slack in this area with different cylinders having compressions of up to 70 psi being acceptable, I'm aiming for no more than 15 psi between any cylinder.

A new camshaft will be fitted with new camshaft bearings and oil pump drive, at the same time I'll be investigating to see if I am able to fit IVECO hydraulic tappets and if so what additional oil ways will need to be drilled.

I'll keep you informed as work progresses.

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Sounds very interesting, though I'm not a diesel guy, any engine build-up is nice, it alwaysmakes me want to go rip apart all of my own engines and make them nice:D

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Personally I think your wating your money balencing the crank, it only spins at 4000 rmp max anyway and they dont do that very often. Land Rover also got the balance of the crank suprisingly good.

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Vulcan, regarding the crank ballance, very possibly but it depends on what you want, after the crank was ground for new bearings the ballance was tested, at 4000 it was fine, nothing exceptional, at 6000 it was beginning to wobble, at 10.000 it was wonky and at 12000 it was trying to climb out of the ballance rig.

It was then ballanced to spin perfectly at 12,000 rpm and turning at 4000 rpm being the supposed maximum engine speed -- which incidentally is only limited by the Bosch FIP capability to deliver fuel -- it is nothing short of silky smooth. The better the engine component ballance the less energy required to turn it, therfore theoretically the more power available at the flywheel, I have always maintained that the best way to tune an engine is to have it perfectly ballanced.

Incidentally the waterways inside the engine were shocking, once this is over I'll publish before and after photos on my site, as I said we recovered well over 1/2 a cup of foundry sand from the waterways. The internal surfaces were shocking and would limit the water flow from the pump, after glass bead blasting they are now smooth and the water flow will be increased and the cooling far more efficient.

We are now looking at what liners are available, the consensus is we go for chrome steel as they have a lower coefficient of friction against forged steel.

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Vulcan, regarding the crank ballance, very possibly but it depends on what you want, after the crank was ground for new bearings the ballance was tested, at 4000 it was fine, nothing exceptional, at 6000 it was beginning to wobble, at 10.000 it was wonky and at 12000 it was trying to climb out of the ballance rig.

It was then ballanced to spin perfectly at 12,000 rpm and turning at 4000 rpm being the supposed maximum engine speed -- which incidentally is only limited by the Bosch FIP capability to deliver fuel -- it is nothing short of silky smooth. The better the engine component ballance the less energy required to turn it, therfore theoretically the more power available at the flywheel, I have always maintained that the best way to tune an engine is to have it perfectly ballanced.

Incidentally the waterways inside the engine were shocking, once this is over I'll publish before and after photos on my site, as I said we recovered well over 1/2 a cup of foundry sand from the waterways. The internal surfaces were shocking and would limit the water flow from the pump, after glass bead blasting they are now smooth and the water flow will be increased and the cooling far more efficient.

We are now looking at what liners are available, the consensus is we go for chrome steel as they have a lower coefficient of friction against forged steel.

Erm.. The pump will run happily to alot more than 4000 rpm. The injectors wont unless you fit bigger nozzles and stiffer springs.

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Vulcan,

Interesting concept, I might get back to Bosch here in Sydney to advise me on that but it was they that said that the rev limiter was the fuel delivery quantity and that the standard Land Rover Discovery type VE pump was factory set by Bosch to deliver that and no more, by limiting the fuel volume they limit the maximum revs to what Land Rover had requested, but I'll go back and ask, not that I really want a 300TDi reving to over 6000 rpm but it could well be an engineered option. :)

I'm really aiming to have a "perfect" engine with (hopefully) improved torque and smoother delivery. In the 200,000 kilometres I've driven in her so far I can only once think of a single occassion where more than 4000 rpm would have been convenient, normal rev range would be 750 - 3500, depending on the gear that would be 0 - 140 kph. with gear changes (ZF Auto) coming in at 2500 - 3000.

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Thanks Nick, :blink: I really needed some light bed side reading matter, actually it was very interestimng to read on how the pump actuallt worked, simple but complicated ! and I'm glad that the pump is at Bosch being fully overhauled (no exchange fuel injection pumps are available anymore due to the age of the unit !) when it comes back it will be totally new even to the extent of Bosch fitting a new pump body, now that I can see how the vane pump works it explanes why that is nessersary as the vanes will wear away the concentric bore.

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Blueprinting, was really a way of getting more BHP and toque etc out of an engine without tunning (which nroke the rules) and by blueprinting each and every conponemt part was "Made" to be as good as it was possible to do, at whatever costs and then all joined up meant that the tolerances of the engine were so spot on that the power outputs where waaaaaay over a std engine with all sorts of tolerances !!

Blueprinting a Private engine is, in my humble a waste of time

However, there is a HUGE difference between blueprinting and building superbly well, with some of the technology being popped into the rebuild.

Some is from "Blueprinting"

Dynamic Balancing, Crank pistons and Rods, the costs are minimal, if nothing else it makes for a smoother engine

Plateaux Honing to new rings, for as good a fit as you can sensibly get vs just a g;lase bust and the old rings cleaned up and shoved back in

On V8s ARP Studs for heads, duplex timing chanins and replacments of worn known issue parts for striong ones ....

and then tuning

Blueprinting was a way of tunning but without changing the basic part, take that money and invest in tuning parts on a 300 TDi I am not the one

to ask or help, but once you have the above solid balanced well builty base then tuning makes a vast difference.

Tuning a std engine, with any of the known weak units still there, or maybe not having quality rebuild things done like a balance does not

make for such a smooth or relaible lump long term

My 2p worth :)

Nige

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Blueprinting, was really a way of getting more BHP and toque etc out of an engine without tunning (which nroke the rules) and by blueprinting each and every conponemt part was "Made" to be as good as it was possible to do, at whatever costs and then all joined up meant that the tolerances of the engine were so spot on that the power outputs where waaaaaay over a std engine with all sorts of tolerances !!

Blueprinting a Private engine is, in my humble a waste of time

However, there is a HUGE difference between blueprinting and building superbly well, with some of the technology being popped into the rebuild.

Some is from "Blueprinting"

Dynamic Balancing, Crank pistons and Rods, the costs are minimal, if nothing else it makes for a smoother engine

Plateaux Honing to new rings, for as good a fit as you can sensibly get vs just a g;lase bust and the old rings cleaned up and shoved back in

On V8s ARP Studs for heads, duplex timing chanins and replacments of worn known issue parts for striong ones ....

and then tuning

Blueprinting was a way of tunning but without changing the basic part, take that money and invest in tuning parts on a 300 TDi I am not the one

to ask or help, but once you have the above solid balanced well builty base then tuning makes a vast difference.

Tuning a std engine, with any of the known weak units still there, or maybe not having quality rebuild things done like a balance does not

make for such a smooth or relaible lump long term

My 2p worth :)

Nige

Jeez :blink: Nigel Barker discussing openly diesel engine tuning :o What are people going to think? :moglite::P:P:P:wub:

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Jeez :blink: Nigel Barker discussing openly diesel engine tuning :o What are people going to think? :moglite::P:P:P:wub:

Nige is coming out and has in fact fitted a cummins to the 90 :P:lol:

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Hi.

He is just turning realistic, he has realized that in the future he will also have to make Squirt work on diesels :-D

Kind regards

Ole

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Thanks Nick, :blink: I really needed some light bed side reading matter, actually it was very interestimng to read on how the pump actuallt worked, simple but complicated ! and I'm glad that the pump is at Bosch being fully overhauled (no exchange fuel injection pumps are available anymore due to the age of the unit !) when it comes back it will be totally new even to the extent of Bosch fitting a new pump body, now that I can see how the vane pump works it explanes why that is nessersary as the vanes will wear away the concentric bore.

I find it slightly strange that Bosch use a material for the vanes in the pump which wears the outside.

Rotary Vane vacuum pumps us either tufnol or carbon type vanes and these don't wear the inside of the pump. They only very very slowly wear themselves out.

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Some very interesting stuff, includes info on, injectors, nozzles etc and the different types of VE and PE pumps how they work. Theres tables and diagram galore, its by no means light reading :hysterical: :

http://www.amazon.co.uk/Diesel-Engine-Management-Robert-Bosch-GmbH/dp/0470026898/ref=sr_1_3?s=books&ie=UTF8&qid=1359169650&sr=1-3

And for just general info and conversion tables, physics, maths and engineering:

http://www.amazon.co.uk/Automotive-handbook-Robert-Bosch-GmbH/dp/3184180042/ref=sr_1_12?s=books&ie=UTF8&qid=1359169650&sr=1-12

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I'm not aware of what seal material Bosch use in the ends of their vanes in the rotary fuel pump only that after over 350,000 kilometers (my engine) they loose the ability to pump at over 135% of the redesign injection pressure (the +35% passes through the relief valve - Bosch claims, not mine) consequently the efficiency of the pump reduces -- read wear -- part of this is the vanes, the rest is micro scoring of the pump body -- read vane bypass--. As the vanes seals are not replaceable I'm not sure if they are spring loaded or centrifugal. In my refrigeration vac pump they are spring loaded, in my mates Mazda RX8 they are oil pressure assisted centrifugal as are the latest air conditioning chiller compressors the oil leakage past the seals into the pump housing acting as seal lubrication.

Blue printing, in my opinion it is essential, in order to achieve any guise of improvement you MUST have a base line and that has to be as near to a perfect engine as you can have, thus every dimension has to be engineered to what the design was, example if the dimensions of a camshafe bearing was 50mm +/- .002 then 50mm is the desired, the ID of the bearings would therefore be quoted as being 50.02mm -o +004 so bearings of 50.03 are, allowing for an ideal oil spacing of .03mm the perfect size, (.002, minimum, .004 maximum, midway .003, ideal) so they would be the ones selected in the engine re-build.

As for engine improvements, well I'm open to comments and ideas, the only one I've come up with so far is investigation of machining the block to take hydraulic tappet or lash adjusters. Bear in mind one thing though next year this engine will take me along the Anne Beadell Highway in South Australia and then up the Canning Stock Route in WA to the Kimberlay Ranges, for some WEEKS I, and Julie will be well over 600 kilometres from the next nearest habitation so the engine MUST be totally reliable, reliabilty comes a long way ahead of any extra performance that may be gained as a by product of this exercise.

If you have Google Planet Earth look up the Anne Beedle Highway and the Canning Stock Route - totally awesome desert sand roads.

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I'll start publishing pics as of next week, its all begining to look good but as I'm budgeted to do this rebuild over a year as the antisipated final cost will be in excess of $6,000.00 you will need to be patient or wait for the thread at the end of the build.

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The camshaft/roller/slider arrangement in Rover engines is massively over-engineered but works very well. The camshafts don't wear and the whole assembly gives little trouble.

BUT we did have a batch of 'genuine' rollers that would wear somewhat octagonal and eventually stop turning, which didn't do the camshaft any good. And as for the valve caps the less said the better as they seem to be made of dinky toy metal. :angry2:

Don't forget to change the oil pressure relief valve piston and spring as it is often forgotten. The oil pumps on the 300tdi don't seem to wear and I have never changed one.

Best of luck with your rebuild :i-m_so_happy:

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That said Jim my current engine has done 300,765 kilometers (186,887 miles) At the moment she is overdue for her 10,000 kilo oil and filter change and cold I get 50psi and at normal running temperature it sweeps from 25 at 2000 rpm to 35psi at 3500 - 10psi at idle -- if the new engine has that sort of pressure range I'll be a very happy chappie indeed.

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Okay, the engine is due back this week from being chemically cleaned, the welsh plugs were removed and the water jacket was shot peaned to remove every skerrick of rust and silt. The big question is what was the original 300TDi engine colour ???? Mine seemed (and I use that word loosly) to be a originally a gold colour but had that little of it on the block that I couldnt be certain if it was actually ever painted.

An old mate has been lined up to powder-coat it for me, I just need to know the original colour - ether that or it will end up BMC green in memory of several Cooper S's that I've owned and loved over the years.

The inside of the block will be powder coated oil repelling white. Once the painting has been done all the machined surfaces will be skimmed around 0.001" to remove overspray as well as some tiny areas of corrosion ("P" gasket) and sump face (some idiot used tyre levers I think to remove the sump) and the block head face to ensure its perfectly flat.

All the alloy parts are away being ceramically coated, the inlet manifold is being sprayed with a silver heat REJECTING coating to assist in keeping the air flow as cool as possible while the other componants simplycoated to prevent corrosion.

The piston skirts have been resprayed with tefflon and the crowns sprayed with a 2000 degree C high temperature heat reflective ceramic coating - as will be the combustion faces of the cylinder head. The coating bonds with the alloyand is only microns thick.

Best part so far the crank was found to be in the tolerances for a NEW unit, not bad for a 1968 engine. The original pistons have been retained as all that was needed was new rings and a fine hone to remove 27 years of glaze - not a single score line . The down side was the ballance of the crank assembly - woefull !!!!

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Not painted, my [new in 1994] 200tdi just had a coating of anticorrosion wax all over the alloy head, block is natural cast steel.

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Too late, but thanks for the input, a 1 litre can of BMC Green two pack engine enamel has been ordered - and in any case a natural cast steel block is plain ugly :blink:

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Do you have a habit of sitting there looking at it.......

...

says he who's also planning an engine paint!

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