i cant say that something ive seen with the hundreds of 3.5s ive bored out
Just wanting to give a "heads up" relating a couple of experiences, both engines 3.5's, first.020" overbore, both done by different reputable professional engine reconditioning machine shops, mine done first, my mates done about 3 years later, both shops said it was common occurrence, they were not happy with the problems that came back to bite them because in my case they had to do a set of "top hats" for it on the second go, my mate scrapped his recon engine and fitted a complete new 4.6.
 
Just wanting to give a "heads up" relating a couple of experiences, both engines 3.5's, first.020" overbore, both done by different reputable professional engine reconditioning machine shops, mine done first, my mates done about 3 years later, both shops said it was common occurrence, they were not happy with the problems that came back to bite them because in my case they had to do a set of "top hats" for it on the second go, my mate scrapped his recon engine and fitted a complete new 4.6.

Maybe but it has little to do with the boring. Liners slip because the block holding them in place cracks.
 
ant .. this in my opinion is the best thread I have read in 6 years of being a member ,,,,,step by step with pictures and instructions etc etc . you are a inspiration my friend . a fine knowledgeable guy .... I cant wait to follow on and enjoy the thread ,,,, till it finally comes to fruition .. I wish you all the success possible ,,, and thank-you for this excellent informative post ,,,well done ,, kind regards Mozz
Really appreciate your kind words Mozz, hope you are well.....it is hoped this thread will help others resurrect an otherwise tired/dying engine!
 
PART 2

Well this evening was designated to clean the bores and see whats what…..

This is the starting point, pretty much all 8 bores look like this

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One bore does look quite bad, and is the one that was the most stuck! With luck we’ll see how it cleans up!

First I liberally sprayed the bore with a solvent degreaser/cleaner and with elbow grease and a Scotch Brite pad (looks like one of them green pan scourer things)

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I had scrubbed the bore to remove the heavy deposits and grime

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Using a good quality honing oil, next is to liberally wipe this all inside the cylinder and the honing tool.

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Now, I would strongly advocate getting hold of some scrape honed tube or similar (not seamed tube for obvious reasons) and practise to get a good handle on rpm and stroke speed as they are interrelated….RAVE indicates a 60deg cross hatch, and the generally accepted angle for most applications from the top edge is 45deg….so aim for between these two…..

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If your hatching is to flat, your stroke speed is too slow, if it is too steep, your stroke is to fast….

For the cleaner bores I used a 400 grit fine set of stones and honed a few times over, one pass is generally around 25-30 seconds. And for the more rough cylinders I started with a 240 grit medium set, then followed by the fine stones.

This will leave a grey paste in the bores, and if you look at the sweep of the paste, you can get a fair indication of the angle of the cross hatching.

Remember, never stop the hone in the bore, always keep it rotating all the way out else you will get vertical scoring, which will allow oil to pass.

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Once you have finished honing, the long and laborious part follows….cleaning the bores…..what I do is give it a quick wipe to check the quality of the honing and if happy, then do the wash out, else you’ll wash it all out, then have to start again….

As washing the bores is such a long winded process, you ideally only want to do it once!

I cannot stress enough, this is the part you don’t want to scrimp on, as it can ruin all your hard work if not down well.

Honing creates fine particles of material that’s gets everywhere, they are small enough to fill the cross hatch grooves…..

Wash the bores out thoroughly with soapy water, then wipe dry…I use white towels so I can see when the grey paste is really all out…..keep washings and drying until the wipes come out clean and with no traces of honing material on….this can take a while, and take a lot of wipes!!

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Result after the medium honing stones…..still more to go!

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Normally you’d measure the bores first before honing to see if they are within tolerance for ovality (roundness), as this will tell you if they are in need of boring out oversized to bring them back to tolerance….as these bores were so mucked up, they needed cleaning out first before they could be measured, else all you’d be doing is measuring rust!

Using a bore mic, or spring loaded bore gauges, measure the bores in 2 axis around 40-50mm down the bore….

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I will do this again tomorrow as I left my 3-4” mic at home so couldn’t measure the bore gauge….

Continue the process for all 8 cylinders, and clean clean clean…..

As the engine won’t be rebuilt straight away, I coated the exposed bores with a light oil which I will repeat over and over until it comes to go back together….

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Allow the block to dry off…..

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There is one bore that is stained and the stain won’t move….it is not pitted, scored or dmaged, the stained area is as smooth as the rest of the bores, it is just a darkened colour….needless to say this was the stuck fast piton in this one….

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All in all the bores have cleaned up very well considering the awful state it was in. Iwill recheck the bore measurements tomorrow and make sure they are within spec….

Next up is the Pistons….which are seized onto their gudgeon pins!!
 
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the measurements at top and bottom of bore and fore and aft will be what it was originally, book measurements are nominal,ie blocks were matched with suitable pistons,with the greatest werar at the top most part rings sweep, but anyhow looking at those bores they seem to have little wear but need reboring
 
Will clean up the pistons, measure the bores again, measure the pistons, stick 'em in the hole and use feelers to measure the gap and check against the workshop manual figures.....a rebore would be the simplest way to get the engine together....but it has only done 26k miles so wear is minimal....hoping we may get away without it.....but it may come down to it.
 
just measure the piston on the bottom of skirt at 90 degrees to gudgeon pin and take that from bore measurement ,leaving your clearance plus wear, as said book nominal size might be 3.500 but originally might have been more or less, its piston size plus clearance compared to actual bore size, or more simply set bore gauge using a micrometer set at piston size , then measure bore
 
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Got £37 for a siezed v8 pile of **** at recycling yard
 
Liners slip because the block holding them in place cracks.
No, not always, certainly not in our cases, it was a result of too light interference fit liner to block at the manufacturing stage, bore in the alloy cylinder block casting was perfect, just a fit issue, I think I read somewhere in another forum that LR pretty much confessed to some glitches on the engine line in days gone by.

There is one bore that is stained and the stain won’t move….it is not pitted, scored or dmaged, the stained area is as smooth as the rest of the bores,
Some of those bores will come up nicely, will be great if they are within tolerance for a rebuild.
Each one of those "stained" areas are what is known as "rust shadows" even though they appear smooth etc, the metal there, or what remains, is much softer than the original bore surface, if you run rings across it it will degenerate very quickly. You will see the same effect on a ball or roller bearing race track, where moisture has rusted the surface, they are the first raceway areas to fail.
 
This is an excellent thread. Do the rust shadows mean the block is toast, or can it be re-linered?
 
This is an excellent thread. Do the rust shadows mean the block is toast, or can it be re-linered?
bored or linered ,some water marks can be deeper than you think ,and so rebore doesnt completely remove them in which case you use liners and then bore to std piston size
 
No, not always, certainly not in our cases, it was a result of too light interference fit liner to block at the manufacturing stage, bore in the alloy cylinder block casting was perfect, just a fit issue, I think I read somewhere in another forum that LR pretty much confessed to some glitches on the engine line in days gone by.


Some of those bores will come up nicely, will be great if they are within tolerance for a rebuild.
Each one of those "stained" areas are what is known as "rust shadows" even though they appear smooth etc, the metal there, or what remains, is much softer than the original bore surface, if you run rings across it it will degenerate very quickly. You will see the same effect on a ball or roller bearing race track, where moisture has rusted the surface, they are the first raceway areas to fail.
you find imperfections in quality in any manufactured items especially from decades ago but we did v8s regularly and in no small number,without issue when the 3.9 came out that was were we found trouble
 
.but it has only done 26k miles so wear is minimal
Why would that dear old Rangie have been put out to pasture with only 26K on it, that's the sort of mileage you want to find on that "special" barn find, low K's all original, just clean off the dust, pump up the tyres, hunt the birds out, and start the engine.
The history of the car must be interesting but, that ain't no way to treat a lady that is capable of giving half a million miles of service.
 
Why would that dear old Rangie have been put out to pasture with only 26K on it, that's the sort of mileage you want to find on that "special" barn find, low K's all original, just clean off the dust, pump up the tyres, hunt the birds out, and start the engine.
The history of the car must be interesting but, that ain't no way to treat a lady that is capable of giving half a million miles of service using three or four new engines.

Sorted that for you. :D:D:D:D
 
From what I see many V8s have low mileage and often you can pick them up cheaper than diesels.
Wonder if its anything to do with the fact that they gargle with a gallon of petrol when you hit the starter.

It would be one of the reasons i would think. :D:D
 

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