Ausmini
It is currently Mon Jul 21, 2025 11:56 pm

All times are UTC + 10 hours




Post new topic Reply to topic  [ 6 posts ] 
Author Message
 Post subject: rubbing pushrods
PostPosted: Sun May 22, 2016 12:57 pm 
Offline
Yay For Hay!
User avatar

Joined: Wed Sep 08, 2004 9:27 pm
Posts: 15912
Location: Wodonga - Vic/NSW border
there was some interesting discussion in another thread a little while ago about pushrods rubbing on blocks. I had my head off yesterday and found that I have exactly this issue...

thick flange 1100S block w/ 12G940 head
RE83 cam
Minisport 1.3:1 roller rockers
1mm spacers under posts

all of the pushrod holes have the same issue, they're too far back and too close to the centre of the bore. Most of the pushrods have the same sort of wear, either in 2 spots or just 1. The one pictured below is the worst

something else to correct next time I have it apart... I guess a bit of paint on them and turn the engine over to see wear it rubs then grind it away, or do you simply bore the hole to line up with the head?

Attachment:
pushrod hole.jpg

Attachment:
pushrod wear.jpg


You do not have the required permissions to view the files attached to this post.

_________________
did I tell you that I won a trophy?


Top
 Profile  
 
 Post subject: Re: rubbing pushrods
PostPosted: Sun May 22, 2016 1:12 pm 
Offline
1275cc
1275cc

Joined: Wed Jan 19, 2005 1:52 pm
Posts: 2582
Location: Brisbane
If my memory serves me correct, when Vizard identified the problem years ago said you need to oval the hole in the block rather than make it simply a bigger round hole. I think that he even had photos of a block cut away in one of his books.

_________________
The bitterness of poor quality (or Crappy Workmanship) remains LONG AFTER the Sweet Taste of Low Price is forgotten.


Top
 Profile  
 
 Post subject: Re: rubbing pushrods
PostPosted: Sun May 22, 2016 7:28 pm 
Offline
848cc
848cc

Joined: Fri Feb 13, 2015 12:10 am
Posts: 66
What were the issues with simply making the hole bigger?


Top
 Profile  
 
 Post subject: Re: rubbing pushrods
PostPosted: Sun May 22, 2016 7:34 pm 
Offline
998cc
998cc

Joined: Mon Jul 07, 2014 12:36 pm
Posts: 611
Location: Bentleigh, Melbourne
Are your rockers centralised over the valve stems?

_________________
67 Deluxe
Dry suspension
1293cc, 11:1 comp, RE 282 camshaft, 45 Weber, extractors etc
4 synchro close ratio gbox
Cooper S brakes, no booster
Stealth box, as Doc says "goes harder and idles!"
RH tank cos I needed it crossing the Nullarbor etc..


Top
 Profile  
 
 Post subject: Re: rubbing pushrods
PostPosted: Sun May 22, 2016 8:07 pm 
Offline
Yay For Hay!
User avatar

Joined: Wed Sep 08, 2004 9:27 pm
Posts: 15912
Location: Wodonga - Vic/NSW border
deluxe67 wrote:
Are your rockers centralised over the valve stems?


yep

_________________
did I tell you that I won a trophy?


Top
 Profile  
 
 Post subject: Re: rubbing pushrods
PostPosted: Tue May 24, 2016 4:19 pm 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39755
Location: near Baulkham Hills, NSW
TK wrote:
If my memory serves me correct, when Vizard identified the problem years ago said you need to oval the hole in the block rather than make it simply a bigger round hole. I think that he even had photos of a block cut away in one of his books.


I seem to remember Matt Read saying he has always just drilled the block holes bigger during a rebuild. This was in the context of better oil drain back, pushrod rubbing wasn't mentioned then.

_________________
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  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 6 posts ] 

All times are UTC + 10 hours


Who is online

Users browsing this forum: No registered users and 74 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.