More cylinder head issues.

[bmcecosse]

White metal only applies to early 803 engines ! But as Phil says - if the shells are showing bronze then they are scrap and the crank needs checking, and v possibly will need regrinding. Only nitrided journals can hope to survive running against 'bronze' shells.

[tim_jnv]

I'll try and get photos to enable a more informed opinion from you guys. is usually to have such high amount in wear of main bearings compared to big ends?
also can you just change piston rings- is it worth it? never had a compression test but rings seem a bit malleable - none broken however, or do you need to do more to bores- they look fine.
Tim

[bmcecosse]

The big end shells may be Al/Sn - so not showing the tell-tale bronze even though worn. The big end shells may also have been renewed which of course is easily done with only the sump to remove. Bores/rings etc is always subjective...and discussed many times. Use the Search facility....

[tim_jnv]

Cheers well there is no scoring to big ends bearings or crank, couldn't fell any wear before removal.
part of the camshaft sprocket/pulley broke away when removing so will need replacing, is worth keeping standard, duplex or is there a mini with tensioner set up? heard all types mentioned on here.

I don't think the car has done that much mileage as whole when you consider it hasn't done anything for 20 years. was relatively late build to jersey. there is no signs of repair to anything in respect of body work certainly that it has been restored prior to what we know has been done.

[bmcecosse]

The Mini tensioner is by far the best - but does mean buying the later cover.

[tim_jnv]

The Mini tensioner is by far the best - but does mean buying the later cover.

thought so take it its just onto the simplex chain?
http://www.minispares.com/product/Class ... .aspx|Back to something like that?

[philthehill]

This is the type of timing chain cover required with the simplex chain and chain tensioner:-
http://www.ebay.co.uk/itm/Classic-mini- ... 5666b80007

[tim_jnv]

http://www.ebay.co.uk/itm/CLASSIC-MINI- ... 1599244214

is it worth it?

[les]

Maybe ---if you've got a mini!

[bmcecosse]

3 people so far think it is..... and if as we are told, there are no knocks/bangs/rattles - then yes it will be.

[tim_jnv]

after consideration of what we have available I at least need new bearings, crank re-ground or new crank price dependent, new piston heads, and will go for new head and rocker shaft.
if you hone the cylinders can you the use standard size pistons?

of course with all this effort and expense considering getting a full recon 1275 engine from mgb hive!!!!

[philthehill]

If you are going to get a 1275cc engine this might be your solution.

http://www.ebay.co.uk/itm/MG-MIDGET-127 ... 4ae2940907

The MGB hive engine is £1349 inc VAT and is on exchange. Do you have a 1275cc engine to give in exchange?

http://www.mgbhive.co.uk/1275_engine.html

[bmcecosse]

And it's VERY expensive for an 'exchange 1275'.... why would you want a 'new' cylinder head ??? What are 'piston heads' ???

[tim_jnv]

the heads we have need a fair amount of work doing to them realistically, and I'm still on the hunt for something bigger, is those fitted to the mini different to minor, midget etc? as been told both and ebay listings sometimes show all then others show only to one, 12g940.

main reason for the question was about honing though!

[les]

Too many things going on at once here.

[philthehill]

It should be remembered that not all cylinder heads with a 940 casting number are the same.
I would suggest that there is not much call for other 'A' series cylinder heads unless the casting number is 12G295.

[bmcecosse]

You can only 'hone' if there is negligible lip in the bores, Just get a service exchange crank from Bully etc. You can sort out a head later - how much work can a head need??? Fitting a 940 head to a small bore engine is entirely possible and very beneficial - but is not just a bolt on job. You suggested a 'new' head - few and far between - but they do come up from time to time.

[tim_jnv]

I say new, serviced exchange head for the 2 we currently have. not a great deal of work to do but enough considering personal and work commitment for 1st half of 2015.

[whyperion]

tim should have asked the question in the block thread (!) (see pic and see you all over there in a few mins)

Meanwhile back to the problem in hand...

The correct free length for a standard 1100cc engine valve spring Terry Pt No: 451-458 is 1.75".
The correct free length for a heavy poundage engine valve spring Terry Pt No: 451-557 is 1.687".
Unless you can be certain that you have heavy poundage valve springs fitted the free length of the springs should NOT be shorter than 1.75" ; if they are they will not be suitable and should be discarded.
ALL valve springs should be the same free length - not greater or shorter than the standard free length.

Not measured as yet ( 4 steel rules in the garages and not found one yet ) , but this is the pack I bought[frame][/frame]

Pictured too is the long spring that broke , I note the number of 'sprials' seems the same. These new ones are the same as another used set I found in the garage. Of course taking the springs back off a collet broke , I will have a look in the other spares saucepan tomorrow night (spare valves are in the bedroom, currently cut off by a set of tape-recorder projects that need transporting to wembley when I get the traveller mobile as a useable beast.

Measuring with an acquired stiff vernier (after working out how to use the tool), The tall spring is 2" long. I assume the shorter ones will be 1.75 as they have all gone with a couple of heads for a tidy up and refurbish. I concluded that the alleged rebuilt head had not been done correctly, supposed new valves were too slack in the valve guides and at least one seat machined too low. The old head I think had at least one worn guide , and a bent valve (!) probably from out of the port which had the broken spring. Both heads are getting appropriate refurbishment and one will go on the Traveller Block (which is being cleaned and new bearings only fitted where needed and new piston rings and oil pump/camshaft going in).

I have a 1960s Practical Motorist, I will post the Terry Springs advert page, which shows (unmeasured) , tall and short springs, but its not clear what one is incorrect , nor what the particular consequences are , its written a bit unclearly/ ambigiously.

[bmcecosse]

The long spring is probably from a 940 head, I have NEVER EVER heard of a 'collet breaking' !!! Who's doing the head refurbishment?