Author Topic: Sloper valve oil feed  (Read 296 times)

0 Members and 1 Guest are viewing this topic.

DAF

  • Star
  • *
  • Posts: 9
    • View Profile
Sloper valve oil feed
« on: 13 August, 2022, 14:02:37 »
Just got the old 1933 m33-11 going, and not sure how the feed line works for the valves? Not getting any oil out of the stud at the base of cylinder. Any help would be great, can't find any info on it. Thx DAF

Bicycle repair man

  • Blue Star
  • **
  • Posts: 59
    • View Profile
Re: Sloper valve oil feed
« Reply #1 on: 14 August, 2022, 17:47:29 »
I think it's the same as the Blue Star. It relies upon crankcase pressure (and possibly a bit of negative pressure from the intake valve) to push a bit of oil mist to the intake guide. The exhaust just gets missed!

Mike Farmer

  • Golden Flash
  • *****
  • Posts: 2549
    • View Profile
Re: Sloper valve oil feed
« Reply #2 on: 15 August, 2022, 10:55:20 »
 :) :) :)

This is just a thought and the way I may go when the start up time finally comes around. Knowing the valve/upper cylinder lubrication is a bit dire in these old marques, I intend to run with a very very small% additive, especially now all fuel is unleaded and E10 contaminated Seriously about 1 in 80 oil mix.. Really next to nothing.

Mike 8) 8) 8)

Y13 Alan G

  • Royal Star
  • ***
  • Posts: 139
    • View Profile
Re: Sloper valve oil feed
« Reply #3 on: 15 August, 2022, 12:11:07 »
I have several pre-war BSA's & a classic (1953) car. I use a FBHVC approved additive to do the following. It stops Ethanol attacking the non-ferrous metals (brass, copper etc) and also rubber components. It prevents valve seat recession (which only occurs over 3,000 rpm) and gives the fuel a 2 points increase in octane rating. I have been using this additive since lead was removed from fuel.( Millers VSp) I do NOT have shares or any other interest in this company!
3 of my re-war BSA's have very suspect valve guide lubrication and I use a spray grease on the valve stems by turning the engine over a few times before every run out. This works fine and I have done as much as 150 miles in a day without noticing any valve guide wear.
The problem of adding oil to the petrol, even at 80 to one, is that it will burn and accelerate the build up of carbon in cylinder head. Because it is burnt on combustion I doubt if any will lubricate the exhaust valve guide. Hope this helps somewhat

DAF

  • Star
  • *
  • Posts: 9
    • View Profile
Re: Sloper valve oil feed
« Reply #4 on: 19 August, 2022, 01:49:39 »
Found out that the ball in the cylinder stud was stuck, it was stopping the oil mist. Thanks for the info