Active Active   Unanswered Unanswered

K Engine Valve Adjustment

Keeping your powerboat under power is a lot easier with good advice. Post your power systems questions here.

Moderators: Don Ayers, Al Benton, Don Vogt

User avatar
mikefet
Posts: 23
Joined: Wed Jul 21, 2010 12:38 pm
Location: Harsens Island, Mi
Contact:

K Engine Valve Adjustment

Post by mikefet » Tue Jun 07, 2011 9:03 am

The engine in my boat was rebuilt several years ago, sat for a few years, and over the last few summers has had maybe 20 hours on it. I have never checked the valve adjustment on the engine. Do you think it would be a good idea to go in make sure they are within tolerance?

I have the floor boards up now from an oil spill in the boat and thought it might be a good time to work on the valves. I'll be able to sit a little lower to see them.

I have never done a valve adjustment on a flathead or otherwise. Didn't have much luck while searching for a "how to" either. I would really appreciate it if someone who has done this before on one the model K's could provide me with a walk though of how to do it. I am mechanically inclined, but unfamiliar with the old engines seeing that I'm only 22 years old.

-Mike
1939 Deluxe Utility - 21 ft.

farupp
Posts: 832
Joined: Sat Oct 29, 2005 6:25 am
Location: Charleston, SC
Contact:

Post by farupp » Tue Jun 07, 2011 11:12 am

It’s a good thing that you are only 22 years old as it is quite a task to adjust the valves. It’s also a good thing that the floor boards are up because you will need all the room you can get and you have to be a contortionist! Have you ever adjusted solid lifter valves before? It isn’t a fun job. Get a pad to lie on or you’ll end up with a real pain in your knees and your back and side.

It will help to remove the fuel pump to allow access to the valves at the front of the engine, and the carburetor to allow access to the valves in the middle and rear of the engine.

Take out all the spark plugs so that you can turn the engine by hand using the nuts that hold the flywheel on. You may need to practice to learn how read and to do the adjustments. If you have an engine around with solid lifters, practice on it. Check the adjustments before you loosen up the adjusting nuts and the lock nuts. If the clearance is close I suggest you leave it unless it is way too tight. Clearances on the Chris Craft 6-cylinder engines are always set with the valves cold.

Here are the clearances and the sequences:

K engine valve clearances (cold):

Intake valve: .010” for all K engines

Exhaust valve: .014” for K, KB, KBL engines
.016” for KFL

This is the sequence I followed when I adjusted my valves. Other may do it differently:

Adjust No. 1 valve with No. 12 fully open
Adjust No. 7 with No. 6 fully open
Adjust No. 9 with No. 4 fully open
Adjust No. 2 with No. 11 fully open
Adjust No. 5 with No. 8 fully open
Adjust No. 10 with No. 3 fully open
Adjust No. 12 with No. 1 fully open
Adjust No. 6 with No. 7 fully open
Adjust No. 4 with No. 9 fully open
Adjust No. 11 with No. 2 fully open
Adjust No. 8 with No. 5 fully open
Adjust No. 3 with No. 10 fully open

When they are properly adjusted and the engine running and warmed up you should hear them clicking just slightly. If you don’t hear any clicking they are too tight. Setting the clearances a little bit too wide is much better than too tight.

The adjustment of the exhaust valves is much more critical than the intake valves. If you hear the exhaust valves clicking a little louder, that is good. You want to hear them clicking; if you adjust them too tight you won’t hear them and there is a possibility of burning the valve.

Good luck and have fun!

Frank
Frank Rupp
1959 22-foot Sea Skiff Ranger
283 Flywheel Forward engine

User avatar
JohnKadimik
Posts: 454
Joined: Mon Jul 07, 2008 8:30 pm
Location: Lake Hopatcong, NJ
Contact:

Post by JohnKadimik » Tue Jun 07, 2011 11:39 am

22 years old, that's refreshing!

User avatar
Capn Taz
Posts: 62
Joined: Fri Mar 25, 2011 9:57 pm
Location: St. Clair Shores, Michigan
Contact:

Post by Capn Taz » Wed Jun 08, 2011 5:32 am

No kidding on that. Fresh young blood in this hobby is good to hear.

Thanks for that posting of the valve adjustment. I have two WBR motors that I need to get the valves checked out on. I have a miss on one cylinder and have pretty much checked everything out and am suspecting a valve issue.

I was going to attempt it myself but found out we have a mechanic in the yard that grew up with these motors and is supposed to be top notch. I think I am going to pay him the first time and just watch!

My information that I was able to glean says they should be checked out every 500 hours or so without fail. This is the first year for me with this boat so I don't know how long it has been.

These flatheads are unique motors... quite a learning curve!
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming 'WOW What a Ride!'"

Just purchased my first Chris, 1959 conqueror - It's going to be an interesting ride!

User avatar
mikefet
Posts: 23
Joined: Wed Jul 21, 2010 12:38 pm
Location: Harsens Island, Mi
Contact:

Post by mikefet » Wed Jun 08, 2011 8:57 am

Thank you Frank. Your reply was extremely helpful. Should be able to manage that fairly easily now, just sounds like it will take some time to get it right.

-Mike
1939 Deluxe Utility - 21 ft.

farupp
Posts: 832
Joined: Sat Oct 29, 2005 6:25 am
Location: Charleston, SC
Contact:

Post by farupp » Wed Jun 08, 2011 9:52 am

Good luck, Mike. It just takes some practice and getting used to using flat blade feeler guages. I also found that when the adjustment was correct, and I tightened up the locking nut, the clearance would be reduced by about 1 to 2 thousands. Practice will tell you how your adjustments end up.

FYI: the adjustment sequence I listed above is for a six cylinder engine with the firing order 1-5-3-6-2-4.
Frank Rupp
1959 22-foot Sea Skiff Ranger
283 Flywheel Forward engine

farupp
Posts: 832
Joined: Sat Oct 29, 2005 6:25 am
Location: Charleston, SC
Contact:

Post by farupp » Wed Jun 08, 2011 10:07 am

Another thought, Mike. I always used the "go, no-go" method for the setting clearances. For example if the correct clearance is .014, I would check the clearance with a .014 feeler gauge and then a .015 guage. Always use flat blade feeler guages. If the .014 would go through gap, but the .015 would not go or went throught with a lot of resistance, the clearance was correct. If the .015 went through easily, the clearance was too wide.

Practice will teach you how to "feel" the correct clearance. There should be just some slight resistance to the guage sliding through the gap between the end of the valve and the face of the lifter.

When all the valve clearances are set correctly, the engine will sound a little bit like a sewing machine when it is running. Just some slight clicking.

Frank
Frank Rupp
1959 22-foot Sea Skiff Ranger
283 Flywheel Forward engine

gbraker
Posts: 575
Joined: Tue Sep 28, 2010 10:22 am

Post by gbraker » Thu Jun 09, 2011 7:54 am

I went through the process last year, and it really helps to have two people. One to move the flywheel and the other to do the adjusting.
Gary R Braker

User avatar
mikefet
Posts: 23
Joined: Wed Jul 21, 2010 12:38 pm
Location: Harsens Island, Mi
Contact:

Post by mikefet » Tue Jul 05, 2011 7:55 am

Wanted to follow up with my results from the valve adjustment. Turned out to be a total success. Adjusting the valves solved the long time problem we've had with the boat bogging down in the higher RPMs. In the past I haven't been able to get over about 2300 RPMs with just myself in the boat. This weekend I had 8 in the boat including myself and was doing 2600 and that wasn't even full throttle. The boat runs better than it ever has.

I had some trouble acquiring a second tappet wrench and ended up having to borrow one from Murley's Marine in Fair Haven. The owner there also gave me the idea of hooking up a temporary starter button that I could press while laying down next to the motor. Along with taking the spark plugs out, this made it a lot easier to spin. The actual adjusting wasn't difficult after getting the hang of it from doing 3 or 4 of the valves. Having that adjusting sequence from Frank was extremely helpful.

Thank you all for the advice. It was such a rewarding feeling to be able to take the boat out and enjoy it like it was meant to be.
1939 Deluxe Utility - 21 ft.

farupp
Posts: 832
Joined: Sat Oct 29, 2005 6:25 am
Location: Charleston, SC
Contact:

Post by farupp » Tue Jul 05, 2011 8:19 am

I'm glad it worked out. Properly adjusted valves are critical. You'll get even vacuum from each cylinder and more efficiency and, as you observed, it runs better than ever.

Thanks for the update.
Frank Rupp
1959 22-foot Sea Skiff Ranger
283 Flywheel Forward engine

User avatar
[email protected]
Posts: 14
Joined: Wed Jul 04, 2018 5:28 am
Contact:

Re: K Engine Valve Adjustment

Post by [email protected] » Sun Aug 30, 2020 9:59 am

Thanks to Mike and Frank for these posts!

Great instructions that completely transformed the top end of my KLC.

Using a remote starter to turn the engine as suggested by Mike made a big difference, as did Frank's sequence which took the mystery out of how far to turn the engine and minimized cranking.

I found it helpful to combine Frank's sequence with the function and tolerances for each valve that I found in another thread and thought I'd share it here in case it's useful for others:

1 valve = Flywheel End

Adjust No. 1 valve with No. 12 fully open - Exhaust - .014
Adjust No. 7 with No. 6 fully open - Intake - .010
Adjust No. 9 with No. 4 fully open - Exhaust - .014
Adjust No. 2 with No. 11 fully open - Intake - .010
Adjust No. 5 with No. 8 fully open - Exhaust - .014
Adjust No. 10 with No. 3 fully open - Intake - .010
Adjust No. 12 with No. 1 fully open - Exhaust - .014
Adjust No. 6 with No. 7 fully open - Intake - .010
Adjust No. 4 with No. 9 fully open - Exhaust - .014
Adjust No. 11 with No. 2 fully open - Intake - .010
Adjust No. 8 with No. 5 fully open - Exhaust - .014
Adjust No. 3 with No. 10 fully open - Intake - .010

Thanks again (and if I got something wrong here, please let me know!)

Post Reply

Who is online

Users browsing this forum: Bing [Bot] and 27 guests