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Boydie

Engine Rebuild & Blueprinting

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Ej, I'd have to say that yes, as its mounted on an engine frame in my "man shed" so I can roate it and assemble it I have time to sit and look at it so a coat of paint will not go astray, especially as I'm spending some hours with a tool grinder removing all the razor sharp edges off it - I believe the word is anal :blush:

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I have come across quite a few 200tdi's painted gold, I've fitted a few new 300tdi's they were very very lightly painted black.

Interesting thread Iain, needs pics though!

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I have come across quite a few 200tdi's painted gold, I've fitted a few new 300tdi's they were very very lightly painted black.

Interesting thread Iain, needs pics though!

There not painted gold, its the colour cast iron goes when it gets very hot.... People seem to think gold block engines are something special, they aint.

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There not painted gold, its the colour cast iron goes when it gets very hot.... People seem to think gold block engines are something special, they aint.

I did see a actual gold plated CAT V12 at a boat show recently so why stop at two pack!! :rofl:

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C'mon guys -- give me a break, I've got on my shelf a 1/2 litre of VHT paint normally used on brake calipers so I'm going to paint the block - from my observations LR must be the only vehicle builder that doesnt paint their engine blocks ! in any case Vulcan, the block is cast steel, not cast iron which is far too brittle for an engine block and a shocker to machine.

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my 200 block machined like it was made from cast iron and so do the mitsubishi rallyart engine blockes we use to mod at work. Cast steels not an issue to machine if you know what your doing as well.

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I think youre wrong there Vulcan, cast iron is heavier than cast steel, the molecuar grain larger, (so its harder to fine machine) its physics are weaker and I just cannot see MMI running their Lancer evolution engines on any thing that would carry more weight than needed., if they do its no wonder that Subaru are more sucsessful on a light weight alloy boxer engine.

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Question without notice.

Which clown in the LR design school came up with the idea of having the three triangular cut-outs in the cylinder head gasket to match the water-ways in the cylinder block between 1-2; 2-3 and 3-4 when there is no corrosponding water-ways in the cylinder head :angry2: all this seems to produce is corosion on the head as there is no easy way for any air trapped in the top of the water-way to easily escape.

Also why are there restrictors in the head gasket corresponding to half the engine block to cylinder head water-ways? I'm seriously considering removing them to see how it affects (if at all) the water flow and engine cooling -- can anyone in the forum assist with some logical answers.

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Okay, getting very close to assembly time, but before I do this has anyone considered welding up the three triangular waterway cores between 1-2; 2-3 and 3-4. While these openings have a cut-out in the cylinder head there is no corresponding aparture in the original or "Evolution" cylinder head and from my observations the narrow space between 3-4 is the cause of 90% of all head gasket failures.

I have a very good welder (he teaches the subject at tech) who is confident of being able to fill in these waterways with a layer of no more than 3mm of weld -in order to simply to seal them off, the block would then be skimmed, the water ways would still be there between the cylinders but the block would no londer have the inherant weakness.

Any thoughts ? I did put a thread up asking why the cutouts are in the head gasket in the first place but I've not had any response. I could be wrong (it happens occasionally) but it seems to me to be if not a defective design then an intension to have corresponding core holes in the head that simply never happened.

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Iain,

Thank you very much for posting this thread. I have now favourited it and really do look forward to following your progress.

I’d really like to offer you some encouragement in your project and hope that you will continue with your write up and add plenty of photos.

We all know that rebuilding a Land Rover engine is relatively straight forward and can be done inexpensively and relatively quickly. The low revving nature of the unit means that exotic techniques and advanced materials could well be considered ‘wasted’ on such an engine and would yield a relatively small performance benefit when compared to the cost/effort involved…

However using such a rebuild as an exercise in engineering – as a personal challenge to see just how good you can make an engine; to use every technique in the book to ensure that a motor is running as minutely sweet as it can (without resorting to performance tuning) makes for a fantastically interesting home project and I understand where you are coming from 100%.

I’ve just mounted a little 3MB 2.25 petrol on my new engine stand ready for a rebuild. I have recently devoured this book on engine blueprinting and am looking to build the engine with as much care as is possible in a home garage. This is my way of learning – if I aim for perfection, I may well fall short but I will learn more about the process and should end up with a really lovely-running motor.

The majority of my plans include measuring, measuring and more measuring (over the last few months I have inexpensively assembled a collection of micrometers, verniers, feelers, bore gauge, digital scales and an old burette) to try and squeeze the tolerance ranges down as much as possible and to apply the principals of best-practice. I won’t be using as many exotic techniques as yourself (though I’d love to read more about them), though I will be having some parts dynamically balanced (at only £95 total for the crank, flywheel, clutch cover, rods and pistons I thought I would treat myself as a little extravagance) and I will also be having the block acid dipped to ensure the waterways are perfect (at £70 its hardly worth the effort of degreasing/stripping the block myself and will do a better job than a standard machine-shop how-wash).

I wish you all the very best for your 300TDi project and, once again, (lots of) photos are very welcome!!!

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The restrictors in the head-gasket are to manage the water-flow: if they were not there, most of the water would take the shortest path - from the water-pump, up past #1 cylinder and out through the thernostat-housing - overcooling #1 and leaving the further-back cylinders undercooled.

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I'm looking forward to the photos - it could become the definitive rebuild thread!

G.

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As a matter of interest, how do you plan to run in this engine ?

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Hi Guys, the project is on hold, the crank came back from being X-rayed at DeHaviland and showed a slight crack so I'll be ordering the 2.8 litre conversion in the new year, as to Sabre's question, fortunatly I live in the Blue mountains so pleasant low reving drives under full throttle up and down hills will be the running-in schedule. The main thing will be to correctly bed in the piston rings, running in the crank and camshaft bearings will be taken care of by using a good quality mieral oil.

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Hi Guys, the project is on hold, the crank came back from being X-rayed at DeHaviland and showed a slight crack so I'll be ordering the 2.8 litre conversion in the new year, as to Sabre's question, fortunatly I live in the Blue mountains so pleasant low reving drives under full throttle up and down hills will be the running-in schedule. The main thing will be to correctly bed in the piston rings, running in the crank and camshaft bearings will be taken care of by using a good quality mieral oil.
Thanks for the feedback

My son's TDi was recently overhauled by an engine rebuilder who advised him to hook up a heavy trailer, and work it on a long drive. I was a bit hesitant, but the guy assured us that if you do not work it in it's early life, it will use oil

Unfortunately, we live in a very flat part of the country, so no real up hills

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Turners have an offer on 300tdi cranks, in case you change your mind(OK the postage would probably be ridiculous)

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It's been more than 3 years, are there no updates on this yet ? (Planning to do my 300TDi in about 18 months time)

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Due to the exorbitant cost of the 2.8 conversion I purchased a new genuine LR Crank completer with matched main and big end bearings, the only modification was to have the two woodruff keyways milled into one single keyway, woodruffs are a waste of time IMHO and if they can be ditched its best to do so, for example now the timing cog as well as the harmonic balancer crank pulley have a full length key instead of a tiny woodruff.  The harmonic balancer now does not rely purely on the crank bolt torque to retain it,

The engine went into a mates car and its doing well, it runs a lot smoother than mine - as you would expect - and I'll be looking to do up his old engine as my next winter hobby.

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11 hours ago, Boydie said:

Due to the exorbitant cost of the 2.8 conversion I purchased a new genuine LR Crank completer with matched main and big end bearings, the only modification was to have the two woodruff keyways milled into one single keyway, woodruffs are a waste of time IMHO and if they can be ditched its best to do so, for example now the timing cog as well as the harmonic balancer crank pulley have a full length key instead of a tiny woodruff.  The harmonic balancer now does not rely purely on the crank bolt torque to retain it,

The engine went into a mates car and its doing well, it runs a lot smoother than mine - as you would expect - and I'll be looking to do up his old engine as my next winter hobby.

Boydie,

Why replaced the crank ? I thought the 300TDi crank could last just about forever ? (My 300TDi sits at 387 000 km) 

Why does it run so smooth, anything in particular that you did ? Did you stick to the standard turbocharger ?

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The crank was replaced because the bearings the crank was scored and the bearings were buggered.  The new crank was obtained along with a new oil pump, bearing and seals. The crank was machined to replace the two woodruff keyways with a single full key and then nitrided to give it additional strength as well as stress relieving it.

All the rotating parts, crankshaft, flywheel, and clutch plate and harmonic balancer pulley were balanced to 12,000 RPM - only because that was the maximum that old mates machine would go up to so thats what we did.  

The bores were honed and new teflon coated pistons obtained, there was negligible bore wear, certainly not enough to warrant a re-bore so standard diameter pistons were selected.

The pistons were selected from a box of about 20 to try to get four that had the exact crown to gudgeon pin measurement, two were skimmed by about 0.0001 mm to match the other two, they were then trimmed at the bottom of the skirts to weigh exactly the same as the lightest piston as were the conrods after being shot peened to stress relieve them before being adjusted for equal centrifugal balance, they were also checked for length and the shortest stretched to match exactly the longest one, bear in mind we are talking thousandths of a millimeter in some cases and weights of .0001 of a gram using electronic scales.  

The push rods were all checked for length and the bore machined to accept Ford V8 hydraulic valve followers and the manual tappets replaced with Ford roller rockers. 

In short we built a full spec racing engine capable of ridiculous engine revolutions that will never go above 4000 RPM :D   

There are 3 water journals between 1-2; 2-3; and 3-4 that do not have matching journals on the cylinder head.  These were TIG welded up (lower heat) and the block skimmed, these journals reduce the sealing distances and the common head gasket failure occurs between cylinders 2-3, I doubt if this engine will ever have this failure, certainly my Disco 300Tdi engine which has had the same modification hasn't ever blown a head gasket in over 300,000 kilometres. 

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Thanks Boydie, very good information that I will keep for when my 300 TDi gets opened up

Listening to the neglible bore wear that you, and others, report, it seem as if the bores will outlast the crank ! What is your oil-change frequency ? 

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I change the engine oil, oil and fuel filters every 10,000 kilometres (6,000 miles) I just use a good quality mineral oil, the 300Tdi doesn't need full or part synthetic.  

The gearbox (s) and axles get their oil replaced every 40,000 and the clutch and brake fluids get replaced every two years. or when the moisture content requires it, 

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