84-85 Trucks & 4Runners 2nd gen pickups and 1st gen 4Runners with solid front axles

Valve lapping

Thread Tools
 
Search this Thread
 
Old Mar 9, 2018 | 05:39 PM
  #1  
Sqrl4runner87's Avatar
Thread Starter
Registered User
 
Joined: Feb 2018
Posts: 11
Likes: 0
Valve lapping

I had to lap in some new valves and this is my first lapping. I just did this one and it's still a lil crusty. Do I lap again or leave it??
Reply
Old Mar 9, 2018 | 08:48 PM
  #2  
millball's Avatar
Registered User
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Aug 2013
Posts: 4,257
Likes: 681
From: Southern Arizona
Lapping valves with hand methods is an old school rite of passage best reserved for lawn mower engines and Model T Fords.

If you want any long service out of your machine, get the valve seats machine cut and the valves machine ground with correct angles and face widths.

The seat in your image is NOT good enough.
Reply
Old Mar 9, 2018 | 10:32 PM
  #3  
Co_94_PU's Avatar
Registered User
iTrader: (-1)
 
Joined: Dec 2012
Posts: 5,433
Likes: 555
From: Colorado
You need to keep going until it has a solid seat 360°..

The multi angle valve grind shows in the image above. Compare the factory section, where the carbon still shows in the image, to the section that has been polished down notice the sharp edge about a quarter of the way through? This is the multi angle..

As stated above it is best to have them done at a machine shop, but again if you want a decent deal you need to keep going.
Reply
Old Mar 9, 2018 | 10:46 PM
  #4  
Co_94_PU's Avatar
Registered User
iTrader: (-1)
 
Joined: Dec 2012
Posts: 5,433
Likes: 555
From: Colorado
You should research the "four angle valve grind".. But here is a crappy phone edit..
90° flat, blue
45° angle, black
60° angle, red
75° angle, yellow


Again research.. It's a crappy quick image
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
brian2sun
95.5-2004 Tacomas & 96-2002 4Runners
13
Nov 14, 2011 09:05 AM
Shifty762
86-95 Trucks & 4Runners
5
Nov 5, 2010 11:20 AM
jason191918
86-95 Trucks & 4Runners
13
Sep 12, 2008 07:03 AM
Gratefuld2
The Classifieds GraveYard
11
Aug 6, 2008 03:48 PM
kevinkal
86-95 Trucks & 4Runners
4
May 30, 2007 05:04 PM




All times are GMT -8. The time now is 06:22 PM.