Ausmini
It is currently Sat Jul 19, 2025 9:26 pm

Board index » Mini Chat » Mini Chat

All times are UTC + 10 hours




Post new topic Reply to topic  Page 1 of 1
  [ 9 posts ] 
  Print view Previous topic | Next topic 
Author Message
Darrell
 Post subject: Valve Resession
PostPosted: Mon May 16, 2016 8:38 pm 
Offline
848cc
848cc

Joined: Sun Apr 10, 2011 4:52 pm
Posts: 186
Do 940 heads suffer from valve recession when running ulp without a fuel additive? my no 2 exhaust valve stem has severely worn down maybe 1/8 in all the others are fine and clearance settings standard.

_________________
1970 Mk 2 Cooper S
Top
 Profile  
 
simon k
 Post subject: Re: Valve Resession
PostPosted: Mon May 16, 2016 8:47 pm 
Offline
Yay For Hay!
User avatar

Joined: Wed Sep 08, 2004 9:27 pm
Posts: 15912
Location: Wodonga - Vic/NSW border
yes they do... but you might have one soft valve stem too?

_________________
did I tell you that I won a trophy?
Top
 Profile  
 
Darrell
 Post subject: Re: Valve Resession
PostPosted: Mon May 16, 2016 8:49 pm 
Offline
848cc
848cc

Joined: Sun Apr 10, 2011 4:52 pm
Posts: 186
That's what I was thinking Simon seeing as the others don't appear to have the same issue.

_________________
1970 Mk 2 Cooper S
Top
 Profile  
 
drmini in aust
 Post subject: Re: Valve Resession
PostPosted: Mon May 16, 2016 9:36 pm 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39754
Location: near Baulkham Hills, NSW
Is the valve sunk into the head, or is the valve stem looking lower when assembled? If the latter, perhaps it has a mk1 exhaust valve there (are 2mm shorter) and 3x oversized 12G940 exhausts.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:
Top
 Profile  
 
Tim I
 Post subject: Re: Valve Resession
PostPosted: Mon May 16, 2016 11:38 pm 
Offline
848cc
848cc
User avatar

Joined: Sat Mar 23, 2013 9:30 pm
Posts: 299
Location: Adelaide
Valve seat recession will close up your clearances, not make them larger.

_________________
Don't listen to what I am saying... just understand what I mean.
Top
 Profile  
 
9YaTaH
 Post subject: Re: Valve Resession
PostPosted: Tue May 17, 2016 8:00 am 
Offline
1360cc
1360cc
User avatar

Joined: Sun Apr 11, 2004 11:32 am
Posts: 12390
Location: Sthrn HiLoLands, NSW, Australia
simon k wrote:
yes they do... but you might have one soft valve stem too?


or poor oiling to the upperworks? hows your oil pump?

_________________
"Show me the Mini!"
Top
 Profile  
 
Darrell
 Post subject: Re: Valve Resession
PostPosted: Tue May 17, 2016 9:10 am 
Offline
848cc
848cc

Joined: Sun Apr 10, 2011 4:52 pm
Posts: 186
Stem is definitely worn, oil pressure is fine, will pull the head off and take a look only done around 10000 ml since rebuild, just seems odd that its only one valve. Thanks for the input guys.

_________________
1970 Mk 2 Cooper S
Top
 Profile  
 
simon k
 Post subject: Re: Valve Resession
PostPosted: Tue May 17, 2016 11:23 am 
Offline
Yay For Hay!
User avatar

Joined: Wed Sep 08, 2004 9:27 pm
Posts: 15912
Location: Wodonga - Vic/NSW border
Darrell wrote:
Stem is definitely worn, oil pressure is fine, will pull the head off and take a look only done around 10000 ml since rebuild, just seems odd that its only one valve. Thanks for the input guys.


sounds like one soft valve... the rebuilder or a previous owner might have bought a cheapie to replace a damaged one. If you run a file against the side of the stem tip you'll be able to to tell without taking the head off

limited experience talking, but the best value valves I've come across I bought from minis plus - the online store is in transition, but these are the inlet version... http://www.minisplus.com.au/old-shop/pr ... d-race-ser

send an email to see if he still has the exhaust version

_________________
did I tell you that I won a trophy?
Top
 Profile  
 
Darrell
 Post subject: Re: Valve Resession
PostPosted: Tue May 17, 2016 6:24 pm 
Offline
848cc
848cc

Joined: Sun Apr 10, 2011 4:52 pm
Posts: 186
Thanks Simon have run the file over the stem and yes its definitely soft had a burr on one side where the rocker wasn't making contact.

_________________
1970 Mk 2 Cooper S
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  Page 1 of 1
  [ 9 posts ] 

Board index » Mini Chat » Mini Chat

All times are UTC + 10 hours


Who is online

Users browsing this forum: No registered users and 76 guests

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  

© 2016 Ausmini. All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.