Author Topic: Advice requested on Valve Guides installation  (Read 1684 times)

0 Members and 1 Guest are viewing this topic.

Offline pancho16

  • Member
  • *
  • Join Date: Jan 2013
  • Posts: 9
  • Location: somerset
Advice requested on Valve Guides installation
« on: 12 Aug 2014 at 10:48 »
Douglas 1951 Mark 5.    Ordered Guides (from Club) for worn nearside cylinder.     Before instal,checked that valves were snug fit in guide    .After instal.valves are VERY tight fit i.e. will not go in!    I can only assume new guides were very slightly oversize & contracted when being drifted in.        What is preferred fix?      Grind valve stem?    Ream out Guide?       Remove & replace gudes & hope new ones are o.k.?

Offline eddie

  • Master Member
  • ****
  • Join Date: Mar 2006
  • Posts: 1654
  • Location: Hampshire, UK
Re: Advice requested on Valve Guides installation
« Reply #1 on: 12 Aug 2014 at 11:32 »
Pancho,
            It is normal practice to ream valve guides after fitting, and then recut the valve seats in the heads. I would not attempt to reduce the valve stems as they may have a surface treatment to prevent the stems picking up in cast iron guides (a problem that has arisen since the change of material for valves used with unleaded petrol).

   Eddie.

Offline pancho16

  • Member
  • *
  • Join Date: Jan 2013
  • Posts: 9
  • Location: somerset
Re: Advice requested on Valve Guides installation
« Reply #2 on: 13 Aug 2014 at 15:44 »
eE)   Eddie-Thanks a lot.        Are  there any Club members who could do this job for me?  (Preferably S. West)       Regards Pancho

 

motorcycle