Forum Home Forum Home > CJ-2A Discussion Area > Tech Questions and Answers
  New Posts New Posts RSS Feed - Adjust, how often? Valves
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Adjust, how often? Valves

 Post Reply Post Reply
Author
Message
jhg View Drop Down
Member
Member


Joined: 07 Nov. 2016
Location: colorado
Status: Offline
Points: 917
Post Options Post Options   Thanks (0) Thanks(0)   Quote jhg Quote  Post ReplyReply Direct Link To This Post Topic: Adjust, how often? Valves
    Posted: 29 May 2023 at 11:50am
I was wondering about valve service. The engine was re-built by the PO (shopped it out to a pro). 
Is it good practice to check adjustment or unnecessary after a re-build once the engine has been run in? Keep in mind I can identify a "loud" tappet but not experienced enough to know whether or not they are (by sound) okay or not as a group.
No idea what the PO did after the re-build.

I will link a video of it running later today.
 
1948 cj2a. Rebuilt L-head, steering, T90, WO 636, steering, brake lines. So far.
Back to Top
Oldpappy View Drop Down
Member
Member
Avatar

Joined: 09 Apr. 2018
Location: Tennessee
Status: Offline
Points: 4812
Post Options Post Options   Thanks (0) Thanks(0)   Quote Oldpappy Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2023 at 12:31pm
I would certainly readjust valves and check head bolt torque on an engine that was recently built and has now been "run in". 

I usually pull the tappet cover and check valve lash at least once a year at tune up, or twice a year on a Jeep that gets driven a lot. A helpful tip I learned on this forum is to only put gasket compound on the side of the gasket against the tappet cover, which "glues" the gasket to the cover. Then smear some chassis grease on the side against the block. This will seal it from leaks and make it easy to remove the cover adjust the valves and button it back up without having to replace the gasket each time.

Here is a fairly easy way to adjust valves which does not rely on the flywheel timing marks which are not always reliable as flywheels often get put on 180 degrees off.

It is my 12 step program Wink


1) Remove all spark plugs, disconnect the battery, and place transmission in neutral.


2) Mark the #1 position on the distributor body with a light colored Sharpie or chalk.


3) Rotate the engine clockwise with a socket wrench until the rotor is pointing at the mark, easier if you have a helper to watch this while you turn the crank. The distributor rotor will turn counter clockwise. When the rotor is pointed to the #1 firing position it is a few degrees BTDC but both valves will be closed.


4) Make a mark parallel to the ground on the passenger side of the crankshaft pulley.


5) Adjust the valves for #1


6) Rotate the engine 180 degrees until the mark made in step 4 is parallel to the ground on the driver side


7) Adjust the valves for #3


8) Rotate the engine 180 degrees until the mark is parallel to the ground on the passenger side


9) Adjust the valves for #4


10) Rotate the engine 180 degrees until the mark is parallel to the ground on the driver side


11) Adjust the valves for #2


12) Done. Replace the tappet cover, spark plugs, cap and wires then start the engine.






Edited by Oldpappy - 29 May 2023 at 12:37pm
If you can't get there in a Jeep you don't need to be there!
Back to Top
Bruce W View Drop Down
Member
Member
Avatar

Joined: 29 July 2005
Location: Northeast Colorado
Status: Offline
Points: 9611
Post Options Post Options   Thanks (0) Thanks(0)   Quote Bruce W Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2023 at 12:35pm
  Adjusting valves after a break-in period should not be necessary. There is nothing that should change during break-in, if the valve job was done properly in the rebuild. 
  “Your Operation and Care Manual” says to adjust them
Twice each year. I know several that would be lucky to get adjusted once a year. Some have been several years and seem to be fine. I also know of several owners who thought their jeep was running fine who were amazed at how much better it ran after an adjustment. Performance deteriorates gradually and you don’t notice it. Restoring that performance is a sudden thing and is noticeable. Keep in mind that the Operation and Care Manual was written for owners who may have used their jeeps as a tractor or as a daily driver/all-around workhorse. We dont use our jeeps that hard. IMO, a yearly adjustment should be adequate for most. One thing about it - more frequent adjustment surely shouldn’t hurt anything. 
BW 
It is NOT a Jeep Willys! It is a Willys jeep.

Happy Trails! Good-bye, Good Luck, and May the Good Lord Take a Likin' to You!

We Have Miles to Jeep, Before We Sleep.
Back to Top
Bruce W View Drop Down
Member
Member
Avatar

Joined: 29 July 2005
Location: Northeast Colorado
Status: Offline
Points: 9611
Post Options Post Options   Thanks (0) Thanks(0)   Quote Bruce W Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2023 at 12:42pm
  OldPappy posted while I was typing. 
His “twelve step program” is very similar to my method and I wont confuse anybody by stating the differences. Simple. 
BW 
It is NOT a Jeep Willys! It is a Willys jeep.

Happy Trails! Good-bye, Good Luck, and May the Good Lord Take a Likin' to You!

We Have Miles to Jeep, Before We Sleep.
Back to Top
Oldpappy View Drop Down
Member
Member
Avatar

Joined: 09 Apr. 2018
Location: Tennessee
Status: Offline
Points: 4812
Post Options Post Options   Thanks (0) Thanks(0)   Quote Oldpappy Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2023 at 12:50pm
Bruce is correct that if the valve job was done properly in the rebuild nothing should change during break in, but when I get an engine that was rebuilt by someone else, no matter if they were a professional or a rookie, I always check to make sure valve lash is set where I want it. It doesn't cost anything but time.

I have an engine right now that was built by someone else and found that the valve lash set to 14 thousands across the board, which isn't too bad, but a little tighter than I like. Too tight will burn the exhaust valves.
If you can't get there in a Jeep you don't need to be there!
Back to Top
jhg View Drop Down
Member
Member


Joined: 07 Nov. 2016
Location: colorado
Status: Offline
Points: 917
Post Options Post Options   Thanks (0) Thanks(0)   Quote jhg Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2023 at 2:06pm
Thanks. I will plan on check  and head bolt torque. A good way to get to know my jeep and given its history regarding due diligence. It is also enjoyable- not too hard, not to time consuming.

I screen shot the 12 step. 


Edited by jhg - 29 May 2023 at 2:08pm
1948 cj2a. Rebuilt L-head, steering, T90, WO 636, steering, brake lines. So far.
Back to Top
Bruce W View Drop Down
Member
Member
Avatar

Joined: 29 July 2005
Location: Northeast Colorado
Status: Offline
Points: 9611
Post Options Post Options   Thanks (0) Thanks(0)   Quote Bruce W Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2023 at 2:13pm
My opinion again, and my way of doing things - 
  Removing the LF fender makes the job much easier. I dont remove the manifolds as some suggest, because of the risk of breaking a stud, and besides, Im an old flate-rate mechanic who doesn’t remove anything that’s not necessary. It’s not that hard to work arount the exhaust manifold and pipe. 
BW 
It is NOT a Jeep Willys! It is a Willys jeep.

Happy Trails! Good-bye, Good Luck, and May the Good Lord Take a Likin' to You!

We Have Miles to Jeep, Before We Sleep.
Back to Top
jhg View Drop Down
Member
Member


Joined: 07 Nov. 2016
Location: colorado
Status: Offline
Points: 917
Post Options Post Options   Thanks (0) Thanks(0)   Quote jhg Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2023 at 3:05pm
Gotcha!
1948 cj2a. Rebuilt L-head, steering, T90, WO 636, steering, brake lines. So far.
Back to Top
TERRY View Drop Down
Member
Member
Avatar
Sponsor Member

Joined: 22 May 2007
Location: BOULDER COLORADO
Status: Offline
Points: 3396
Post Options Post Options   Thanks (0) Thanks(0)   Quote TERRY Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2023 at 3:47pm
The hard part is wiggling the valve cover out of the way.Ouch
BOULDER 48 2A
Back to Top
jhg View Drop Down
Member
Member


Joined: 07 Nov. 2016
Location: colorado
Status: Offline
Points: 917
Post Options Post Options   Thanks (0) Thanks(0)   Quote jhg Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2023 at 10:47pm
Here is the short clip of my jeep engine running.
1948 cj2a. Rebuilt L-head, steering, T90, WO 636, steering, brake lines. So far.
Back to Top
Oldpappy View Drop Down
Member
Member
Avatar

Joined: 09 Apr. 2018
Location: Tennessee
Status: Offline
Points: 4812
Post Options Post Options   Thanks (0) Thanks(0)   Quote Oldpappy Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2023 at 11:44pm
Sounds like it is running pretty good to me. 
If you can't get there in a Jeep you don't need to be there!
Back to Top
jhg View Drop Down
Member
Member


Joined: 07 Nov. 2016
Location: colorado
Status: Offline
Points: 917
Post Options Post Options   Thanks (0) Thanks(0)   Quote jhg Quote  Post ReplyReply Direct Link To This Post Posted: 30 May 2023 at 12:02am
That is re-assuring. I thought so too but have little experience to compare it to in regards to jeep engine sound. My 12 valve, now that is an engine I am familiar with.
1948 cj2a. Rebuilt L-head, steering, T90, WO 636, steering, brake lines. So far.
Back to Top
mike in oregon View Drop Down
Member
Member
Avatar
Sponsor Member

Joined: 17 Jan. 2008
Location: Fall Creek Or
Status: Offline
Points: 1988
Post Options Post Options   Thanks (0) Thanks(0)   Quote mike in oregon Quote  Post ReplyReply Direct Link To This Post Posted: 01 June 2023 at 8:36pm
Hey do you guys go .016" or .014" I am getting forgetful and cant remember, Thanks
MIKE IN OREGON
President of Oregon Flat Fender Club.
http://www.facebook.com/pages/Oregon-Flat-Fender-Club/222864787838570

46 CJ2A 38007
46 CJ2A 79863
BANTAM T3-C 25314
Back to Top
jhg View Drop Down
Member
Member


Joined: 07 Nov. 2016
Location: colorado
Status: Offline
Points: 917
Post Options Post Options   Thanks (0) Thanks(0)   Quote jhg Quote  Post ReplyReply Direct Link To This Post Posted: 01 June 2023 at 9:49pm
.016
1948 cj2a. Rebuilt L-head, steering, T90, WO 636, steering, brake lines. So far.
Back to Top
WeeWilly View Drop Down
Member
Member
Avatar
Sponsor Member x 2

Joined: 07 May 2009
Location: Clayton IN
Status: Offline
Points: 3422
Post Options Post Options   Thanks (0) Thanks(0)   Quote WeeWilly Quote  Post ReplyReply Direct Link To This Post Posted: 01 June 2023 at 9:57pm
 On a rebuild I do a tight .016 to allow for a little wear for break in.

    Jim
47 CJ2A (Ranch Hand) 48 CJ2A, 48 Willys truck, T3C 3782, M274 (Military Mule)
Back to Top
RCR View Drop Down
Member
Member
Avatar

Joined: 07 Jan. 2018
Location: Illinois
Status: Offline
Points: 2
Post Options Post Options   Thanks (0) Thanks(0)   Quote RCR Quote  Post ReplyReply Direct Link To This Post Posted: 12 June 2023 at 7:14pm
Adjusted the valves on my 46 L-134 yesterday . Runs a lot better . Even had to readjust the idle down some . Thank fellas for your knowledge !
Back to Top
Downs View Drop Down
Member
Member
Avatar

Joined: 08 Sep. 2021
Location: Hunt County Tex
Status: Offline
Points: 179
Post Options Post Options   Thanks (0) Thanks(0)   Quote Downs Quote  Post ReplyReply Direct Link To This Post Posted: 13 June 2023 at 1:35pm
Originally posted by Bruce W Bruce W wrote:

My opinion again, and my way of doing things - 
  Removing the LF fender makes the job much easier. I dont remove the manifolds as some suggest, because of the risk of breaking a stud, and besides, Im an old flate-rate mechanic who doesn’t remove anything that’s not necessary. It’s not that hard to work arount the exhaust manifold and pipe. 
BW 

This is the way.  The fenders are very easy to remove.  Especially if you're using something like a 20v electric driver, you can have the fender off in no time and have easy access to that side of the engine. 
1946...ish CJ2A
1976 CJ5
1995 XJ
Back to Top
 Post Reply Post Reply

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.06
Copyright ©2001-2022 Web Wiz Ltd.