• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

replace valves, replace seats also?

Share this page

R

recordsj

Jedi Warrior
Offline
I have a 1500 midget engine I am rebuilding.
If I replace the valves, should I be replacing the seats also even if the seats are OK?

If seats are replaced do they need to be ground or when you purchase them there should be no griding necessary?
 
If your car was equipped with a catalytic converter and most of the late model 1500 midgets had one, these engines were design to run on unleaded fuel. If your engine has hardened valve seats you may only need to machine the valves and the seats. The only way to make sure of this is to take the head off and examined the area where the outer edge of the valve makes contact with the head for pitting and erosion under your exhaust valves. You will need to inspect all seats very carefully as well inspecting all your valves on the outer edge. You should have at least .040’ of valve material out on the outer edge. If you do replace your valves they will have to be lap in to the newly machined seat. Don’t forget to pay close attention to your valve spring tensions and your rocker shaft and rockers, and don’t forget to check those valve guides clearance too.
 
Back
Top