[Healeys] Hardened seats in a cast iron 100 head

[Bob Spidell]

Well, that wasn't OP's question.

You can certainly get by without the inserts in a lower compression 
engine that isn't run hard but, if you're doing a head job then why not? 
The risk of cracking is legitimate, that's why you need a good, 
experienced machinist to do it; a good machinist will recommend against 
it if he's encountered problems with similar heads.

On 8/26/2024 8:27 AM, Kees Oudesluijs via Healeys wrote:
>
> In most cases hardened valve seats were/are not necessary. There was 
> only a small handful of engines that gave trouble after introducing 
> lead free petrol.
>
> Op 26-8-2024 om 16:43 schreef Bob Spidell via Healeys:
>> My dad had our BN2/100M's head redone--valves, guides, etc.--by a 
>> local speed shop we trust (the machinist is a meticulous Kiwi who Dad 
>> said got really excited when he saw 'Weslake' cast in the head). 
>> Unfortunately, Dad isn't around to ask, but they almost certainly 
>> installed hardened exhaust valve seats; it's been SOP since, well, 
>> since lead was removed from gas. No issues, and I had it out on the 
>> road a couple weeks ago.
>>
>>
>> On 8/25/2024 7:44 AM, Michael Salter wrote:
>>> I am still using cast iron heads on both my 100's. Amazingly neither 
>>> have serious cracks as are so common on these.
>>> I am really picky and don't particularly like the different sound 
>>> that a 100 engine with an aluminium head makes so would like to 
>>> continue using these cast iron ones.
>>> I'm contemplating installing hardened seats in one.
>>> Hase anyone done this successfully?
>>
>>
>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/healeys/attachments/20240826/e3929adc/attachment.htm>