Replacement Cylinder head

Technical MGB discussion
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Hazza1190
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Joined: Mon Jun 25, 2018 2:04 pm
Forename: Harry
Surname: Bukin
Location: Devon

Replacement Cylinder head

Post by Hazza1190 » Mon May 18, 2020 3:25 pm

Hi Guys,

The history of this story is that my current 12H2709 is cracked beyond repair. I was contemplating doing a V8 swap but i have decided against the idea now, maybe next time. Therefore, I have been looking for a replacement 12H2709 head. There are a few on ebay but not sure if they're worth the risk. This is one of them -

https://www.ebay.co.uk/itm/mgb-gt-Cylin ... 4156967195

Is it worth the £££? The only reason that im willing to pay this much is because i would have sent it to Peter Burgess anyway but this seems to have already had some work done.
Thoughts would be appreciated!

Cheers,
Harry.

Vic Butler
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Forename: Vic
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Location: North West Hampshire

Re: Replacement Cylinder head

Post by Vic Butler » Mon May 18, 2020 4:42 pm

In picture 8, the third combustion chamber up does appear to have a mark on the exhaust valve seat.
Peter Burgess is able to modify any head to 12H2709 spec so there's no need to limit yourself to finding one.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine

Hazza1190
Posts: 41
Joined: Mon Jun 25, 2018 2:04 pm
Forename: Harry
Surname: Bukin
Location: Devon

Re: Replacement Cylinder head

Post by Hazza1190 » Mon May 18, 2020 5:49 pm

I didnt realise that he can make any head to the 12h2709 spec. I have only seen a couple non 2709 heads come up on Ebay, all being returned already. Maybe it's just a waiting game! How much should I be looking to spend on a standard centre oil feed head?

Ian Fozzard
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Re: Replacement Cylinder head

Post by Ian Fozzard » Mon May 18, 2020 7:30 pm

Harry, I would be extremely wary buying something like this from an unknown source.
It may be OK of course, but you are really buying a complete unknown - "modified" by whom? Could be much worse than standard. Provenance is all with these items.

Ian F
1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, Clipper Blue, Blue trim and weather gear

Vic Butler
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Forename: Vic
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Location: North West Hampshire

Re: Replacement Cylinder head

Post by Vic Butler » Mon May 18, 2020 10:02 pm

Any centre oil feed head from the 1.8 engine will do. The Austin/Morris/Wolseley 1800 heads can be modified so there's no need to search for an MGB head although I suspect the latter are more common than the former. A head from an 'S' version is the best.
I agree with Ian about so called modified heads. In the hands of someone who doesn't know what they're doing these heads are next to useless.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine

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Peter Cresswell
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Location: Stone, Staffordshire

Re: Replacement Cylinder head

Post by Peter Cresswell » Wed May 20, 2020 10:19 pm

It is always a lottery buying second hand parts and as for cylinder heads, any BMC head is notorious for cracking! The one the link goes to on ebay has been modified which is why they are asking that amount of money for it. It does look like a home modified head.
There are currently two 12H2709 heads on ebay - one is £150 and the other £175. They are quite rare and are sought after, so are more expensive than other heads except perhaps the early 3 bearing heads.
If you don't want to gamble on ebay, try:
Mechspec at Doncaster - http://www.mechspec.co.uk - I got my 12H2709 from them,
Andy Jennings 01489 790611
Welsh MG Spares at Wrexham -www.welshmg.co.uk
One of these should be able to help you to source another 12H2709 head.
Ask if they will take it back if you find it is cracked, but you won't know until it is magnaflux crack tested, which you will be able to get done an any engine remanfacturer, or perhaps a general machine shop. Don't just take their word for it being servicable as the cracks can rarely be seen. I bought a Cooper S head off ebay and it had 18 cracks!
Pete
1969 MGB Roadster
2011 MG 6 TSE Magnette
2007 Mercedes SLK
Plus 32 other cars since 1965

ChargedAutoGT
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Joined: Wed Nov 21, 2018 9:37 pm
Forename: Graham
Surname: Moore

Re: Replacement Cylinder head

Post by ChargedAutoGT » Mon May 25, 2020 10:13 pm

and if a seller tells you it's been crack tested, ask where it was done, & to see receipt!
G

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