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can this block be rebored ?

Posted: Sat Sep 28, 2019 3:30 pm
by burnham28
I have been given a complete 1098cc engine everything is there but its all in pieces. I have cleaned one of the pistons off and there are numbers and letters i.e. m2007 front mowog 844. Can this block be rebored or has it been rebored to its capacity. There are no +20, 40 etc stamped on the piston.

Re: can this block be rebored ?

Posted: Sat Sep 28, 2019 4:00 pm
by philthehill
The only way for sure to determine if it can be re-bored or not (or sleeved) is to measure the bores as they are now.

Re: can this block be rebored ?

Posted: Sun Sep 29, 2019 1:10 am
by BobHood
Burnham28, where are you based? I have boring equipment and the necessary mics for measuring bore size and wear. I'm based in Borehamwood, which is North London, if you're nearby then I can come and measure the bores for you.

Re: can this block be rebored ?

Posted: Sun Sep 29, 2019 10:31 am
by oliver90owner
Even measuring the piston diameter could enlighten if it is actually close to standard. Piston size and feeler gauges can be helpful to determine which end of the spectrum of sizes it might be, but PTH’s ‘for sure’ method will be needed if it is not at least close to standard.

Does it actually need reboring? Again, only close inspection and measurement will provide the answer.

Re: can this block be rebored ?

Posted: Sun Sep 29, 2019 10:48 am
by pgp001
I know I will get shot down for making this statement but..........

If there are no plus sizes marked on the pistons, there is a very good chance it is still on standard bore, that is exactly the situation my spare engine was found in as well.

Another "indicator" is whether the aluminium number plate is still rivetted in place, these often but not always go missing when the engine has been bored and decked.

As stated previously, you really do need to get it measured, but I am just trying to offer a glimmer of hope for you :)

Phil

Re: can this block be rebored ?

Posted: Sun Sep 29, 2019 2:00 pm
by burnham28
Thanks chaps for all your replies.I did think that as the pistons didn't have any +20, +40 stamped on them the block might have been standard which would mean there will be plenty of meat left for reboring. The bores have a very minor amount of surface rust on them. Thanks Bob for the offer of reboring but I am based on the Surrey/ Sussex border so will find somewhere nearer. As the engine came in pieces it's going to be fun putting it back together having not taking it apart, but I am assured it's all there in a big box somewhere.

Re: can this block be rebored ?

Posted: Sun Sep 29, 2019 7:59 pm
by SUE482
Dont forget its essential to match up the big ends and main caps if its all in bits, there should be markings on each one showing the relative position on the crank. :roll:

Re: can this block be rebored ?

Posted: Mon Sep 30, 2019 11:50 am
by oliver90owner
In addition to SUE, The markings should all be made on the camshaft (timing) side of the engine. Well, hopefully they will, unless made by a non-engineer!

Re: can this block be rebored ?

Posted: Mon Sep 30, 2019 12:54 pm
by philthehill
The main caps are not marked but as they are handed and of three different designs it is difficult to get them wrong.

Make sure that the main bearing cap location dowels are in place as they are a most important item. They stop the caps wandering. :wink:

https://www.moss-europe.co.uk/dowel-mai ... soc=137914

Re: can this block be rebored ?

Posted: Mon Sep 30, 2019 3:58 pm
by burnham28
I intend to have an exchange crankshaft complete with bearings etc. The shells on the old one are showing signs of wear as the copper is starting to show through but I've seen worse. As its all in pieces anything else I should be looking at ?
Is a duplex timing gear a good idea.

Re: can this block be rebored ?

Posted: Mon Sep 30, 2019 6:00 pm
by philthehill
A duplex timing chain kit with lip seal timing cover is an excellent idea.

A duplex timing chain kit with 'A' Plus chain tensioner is even better.

Replace all the core plugs.

Remove the oil gallery oil plugs, clean the oil galleries and fit new plugs.

Replace the old type element filter with the screw on/off type.

Replace the oil pump. It is the beating heart of the engine.

Replace the cam followers. They may look ok but they never are on a used engine and they are cheap to replace.

Whilst the head is off replace the by-pass hose stub.

Replace the valve springs - there are usually some genuine Terry valve springs on 'e' bay. I bought a NOS set of Terry Cooper S double valve springs still their Terry box for next to nothing off 'e' bay. Use the single springs only with the original valve spring set up.

Re: can this block be rebored ?

Posted: Wed Oct 02, 2019 4:26 pm
by burnham28
I took the block to the engineering shop to be measured. I was told it was a standard block which had never been rebored although there was a bit of wear so it's going to be rebored +20.

Re: can this block be rebored ?

Posted: Wed Oct 02, 2019 4:26 pm
by burnham28
I took the block to the engineering shop to be measured. I was told it was a standard block which had never been rebored although there was a bit of wear so it's going to be rebored +20.

Re: can this block be rebored ?

Posted: Wed Oct 02, 2019 6:16 pm
by philthehill
Make sure that you retain the engine number tag for future reference. They usually get removed and discarded before the boring bar is fitted to the block.

Re: can this block be rebored ?

Posted: Wed Oct 02, 2019 10:31 pm
by pgp001
Those engine number tag rivets are almost impossible to remove intact, to get mine out I used a thin cutting disc in a Dremel to grind a screwdriver slot across them, they came out fairly easily with a big screwdriver.

Phil

Re: can this block be rebored ?

Posted: Thu Oct 24, 2019 5:11 pm
by burnham28
Well the block is now back having been bored +20 and have pistons to fit. As PTH advised have new core plugs to fit whats the best way of removing the old ones and what sealant do I put the new ones in with? I have a reconditioned crankshaft, cylinder head and rocker shaft all ready to fit together with a new oil pump, duplex timing gear and water pump so now the fun begins putting the engine back together after being given it in pieces any advise will be much appreciated

Re: can this block be rebored ?

Posted: Thu Oct 24, 2019 5:23 pm
by philthehill
To remove the core plugs I just knock a small chisel/screw driver through them and just lever them out.

Before fitting run a rotary wire brush mounted in a electric drill around the core plug seat so as to clean the seat.

Coat the core plug seat in Hylotyte Red 100 (or similar) and place the core plug into the seat dome outwards and smack the centre of the dome with a flat punch. This action flattens the core plug so gripping the core plug seat. See the old core plugs for final shape/fit.

https://www.ebay.co.uk/itm/Hylomar-Hylo ... SwzO9dmceI

Re: can this block be rebored ?

Posted: Mon Nov 11, 2019 3:43 pm
by burnham28
Well all the big ends are in place and have been torqued up to 60 as per the workshop manual. I have managed to get the pistons in and have torqued the connecting rod bearings up to 35. Whilst building the engine I have used copious amounts of oil and have been turning the engine over which has become tighter and tighter until after torquing up the con rod bearings I now cannot turn the engine. What have I done wrong?

Re: can this block be rebored ?

Posted: Mon Nov 11, 2019 4:59 pm
by philthehill
Was the crankshaft turning as it should be before fitting the conrods/pistons?

If it was below are some reasons as to why it is now not turning.

1. Have you put the con rods in the right way round so as to have the right offset?

2. Did you fit the con rod caps the right way round?

3. Are the big end bearings the right size?

4. Have the con rod bearings been fitted with the shell tangs fitted correctly into the recess of the rod and cap?

5. Have the big end caps been filed or played around with? I got caught out once with a Standard 8 which had the big end caps filed to take out the bearing play.

Re: can this block be rebored ?

Posted: Mon Nov 11, 2019 5:10 pm
by burnham28
Hi Phil
Yes the crankshaft was turning as it should but was getting progressively stiffer as I put the pistons in. I could turn it just about until I torqued the con rod bearings up after that I couldn't turn it.