Adjusting valves - Speedy Mopar Flathead 6

[Semmerling]

 

 

I tried to track down as much as possible to see what has been offered up on the subject of adjusting the valves on the flathead 6.
Setting aside all the suggestions for solo numbers, hot or cold, stopped or running, gloves or salve, I came up with the following, 

 

FOR THOSE READING THIS THREAD, USE THE RECOMMENDED GAP FOR YOUR CAR'S YEAR

THE PROCESS IS CORRECT AND ACCURATE

THIS IS A NEW IMPROVED IMAGE

 

 

 

 

 

 

Edited March 10, 2023 by Semmerling
improved pic

[Semmerling]

Good points, we'll add..

 

- take the spark plugs out

 

- Turn clockwise using a starter handle for TDC.

 

Is there anyone who might be able to offer up a simplified I/E gap by engine year/type? 

 

 

[tom'sB2B]

Here is another option: 

https://youtu.be/8G3MJGuKIQ8

 

Pull the wheel and inner fender. Pull the valve covers. Let the engine come to temp and adjust while engine is running.

 

Edited February 26, 2023 by tom'sB2B

[Semmerling]

I am asking if the document is correct if one was to do it following the prescribed process in the manual.

 

Without knowing  which is EXHAUST and which is INTAKE, that is the best video of how to stick thin metal into moving metal pieces on the web. 

 

Edited February 26, 2023 by Semmerling

[9 foot box]

   There are a few variations of valve tappet clearance on the flathead engine. The first is from my FSM for a 218, the second is from my manual for W-series trucks. Tech tips says .010” ex and .008” intake. I’ve only adjusted one of my P15 cars with a 230 c.i. tappets, but I set them at .010” intake and .012” ex, because I drive highway speed. I set each piston at it’s firing position and adjust the tappet clearance. I think using feeler gauges in a running engine hammers and distorts them. An older engine could have different specs, but I’m just giving my opinion and references to some discrepancies. Exhaust valves need more clearance to prevent burning the edges of the valves and seats. Maybe Tim from AOK Boys can set us straight. Rick D.

[Semmerling]

Very helpful and very welcome. My concern is teaching those that do not understand the basics. Your work is fabulous, but in some ways inaccessible. 

 

Let me ask you directly, is the information on the guide a made up above correct?

And if it is, should we also provide the following image as well. 

 

Lastly, what would have been the factory recommended gap for a 1934 Dodge DR.

 

Many, many thanks for taking the time to reach out.

 

 

Edited February 28, 2023 by Semmerling
improved pic

[Sniper]

the reason exhaust valves more clearance is that they run hotter.  When they run hotter the stem gets longer taking up more clearance.  If there is insufficient clearance to account for this growth then the exhaust valve will, eventually, not full close and that is what burns them up.  This is why the truck spec is larger, those engines are expected to run harder than a pass car.  When in doubt it is better to have a bit too much clearance than not enough.

 

Let's not forget that valve adjustment will also affect the power output and the cranking compression tests.  Too much clearance will drop both numbers.

Edited February 26, 2023 by Sniper

[Semmerling]

On that very topic, I returned the INTAKE to .008 and the EXHAUST to .010 with a note about highway speed.

I think the we are close here, did you see any errors?

 

[martybose]

Like most simplified adjustment procedures, this one has errors.  If you go through the steps listed, you will adjust the intake valves on #2 and #5 twice, and one of them will be wrong.

[Semmerling]

I appreciate the chance to correct it. Thanks for letting me know. 

Stages matter......
THIS IS THE EXACT TEXT FROM THE TECHNICAL PAGE RIGHT HERE AT P-D

--------------------------------------------------------------------------------------------

Exhaust valve clearance .010
Intake valve clearance .008

 

Stage A, #1 and #6 at TDC, #1 in firing position
Stage B, #1 and #6 at TDC, #6 in firing position

To move from Stage A to B, manually turn the engine 1 revolution.

Stage A – Adjust #1 Both valves, #2 Inlet valve, #3 Exhaust Valve, #4 Inlet valve, #5 Both valves.
Stage B – Adjust #2 Both valves, #3 Inlet valve, #4 Exhaust valve, #5 Inlet valve, #6 Both valves.

-------------------------------------------------------------------------------------------------------------------
At the proper stage (see the two ARROWS) in the guides, do you still see a problem?

 

Given that, reviewed and corrected SIMPLIFICATION should result in something that actually supports learning,

It sure beats overly complex and highly subjective, scattered everywhere information.

Or worse, not understanding why something is correct, lets see if we can finally improve on that. 
 

 

Edited February 26, 2023 by Semmerling

[Semmerling]

[harmony]

I've read a couple things that make common sense to me in this thread so far.  9 foot box made a good point for those that believe the clearance setting is critical.  

9 hours ago, 9 foot box said:

I think using feeler gauges in a running engine hammers and distorts them

With that in mind a guy should have a feeler gauge for each tappet, if accuracy is that important.  Then throw each of them in a drawer marked shim stock material after one single use.  The other interesting thing I read was " It's better to hear them than to smell them"

I believe that the process is subject to an individuals interpretation of "snugness"  

If a guy usually drives his car as a grocery getter as well as going back and forth across town from home to his shop most of the time, but then once or twice a month during summer months he goes on a 2 hour highway cruise with his buddies, is he really going to pull the wheel and inner fender and replace the side plate gaskets each time, just so he can get the tappets set just right?  According to his interpretation of "snugness" of course, which is probably different than the next guy anyways. 

 

I set mine cold, allowing 2th. on each one.  I hear a particular sound when the engine is cold, and another particular and slightly different sound when the engine is warm.   I might be off by one half of a th. on one of them maybe, but I don't stay awake thinking about it or find myself scrambling for the various tools that I'll need to pull that wheel and inner fender off again to correct my error.

[9 foot box]

   From a Motors manual. I would keep your .008”int. and .010”ex. settings. Rick D. 

[Dave72dt]

I've seen those two step valve adjustments on various other engines and repair guides, have tried them and found them not as accurate as setting each cylinder individually on TDC compression.  I do an initial cold and follow up with a hot adjust.  When you're getting paid for it, it has to be right. 

[Semmerling]

In approaching helping people that do not have the depth and breath of mechanical experience that professional practitioners or even the casual weekend warriors have the process has to be reasonably stream lined. By and large the best that P15 has to offer is lost because of an abysmal search engine. Anybody that has used it, really spent time with it knows this. I can go on at length that absent the ability to tell the search engine not to allow certain words ("-PVC") means all is pretty much mishmash.  Many good people have come forward with some very good material over the years but much of it is presented from the perspective that relies on fairly good competencies and skills. That is great for the 72% of the curve that is over 65 but it makes bringing forward the next generation much more difficult.

Hammering the feeler gauge - Of course it hammers the feeler gauge, but that isn't why some folks do the "pogo." The best of them do it because they actually have done it enough to actually come closer to getting it right. Those people are not the ones that are going to do the majority of of it by the Factory Shop Manual."

"Better to hear it than smell it" - That also came from folks right here. It's a practical statement on "if you hear it, adjust it properly as just getting rid of the sound may later make you get rid of the block."  Snugness thing is a wipe off the oil kind of issue, feeler work unless its dripping in oil and on a "pogo" is what it is. 

Comments by 9-Foot-Box are of the very best kind. He offered up the last missing part of these guides, that being, the EXACT FACTORY RECOMMENDED SETTINGS broken down by engine types/year/options etc.  I have what I need from my manuals, but I remain curious what others might think. If I had access to that information I could do one of the following:

 

- Set it all out properly in a SIMPLE table  right here and find the means to get it to the "How To" section and pray that the search engine finds a better search engine in the future. 

- Distill all of it down to 5 or 10 groupings that deal with the 2 standard deviations crowd of crankers, grinders and deckers. 

- Come to find that the vast majority of it all breaks down to .009ish for intakes and .011ish for exhaust.

Your thoughts on drawers and feelers - Better yet, take a 12" piece of something  and mount the right for your rig right on it.  That way you can easily work it either through the wheel well porter or whatever. I've seen them with the Intake feeler on one end and the exhaust feeler on the other. 

The business about ever, repeat ever, feeling the need to change the adjustment is what this is all about avoiding. These should last 10,000 miles or more. My car has been in the family for four generations and, outside of the rebuilds, 11 adjustments. The important point to my mind is doing it well once in a long great while. Not sure how we got from "If LOTS of highway driving" to "2 hours" but we did. Trust me when I say that making up these guides takes more time than adjusting the valves ever did over the last 90ish years. 

Appreciate the comments. 

Edited February 26, 2023 by Semmerling

[keithb7]

I quite enjoy performing valve sets in my old Mopar cars. Its fun and very rewarding. I have set them while hot, static. Cold too. I have checked them while the engine is running as well. I made a fairly lengthy detailed video for beginners who want to tackle a valve set.  One thing I figured out, when you are playing with tappet lash, you are indeed also playing with valve timing. Valve timing has a large effect on engine power at different operating RPM's. This is the principle behind the "RV" cam. More power at lower RPM's.  Ever wonder why they recommend to set your valve lash a little looser for extended hi-way trips? Say you were going to head out on a week long hi-way trip. Set them a little loose so the valves can run cooler. The wider the gap, the longer the exhaust valve gets to sit on it's seat and cool. The law of diminishing returns holds true here as well. You can only go so wide and then other bad things start to happen. 

 

When I remove the wheel well inner fender window to set valves, after I am done I leave it out for a while. I drive around for using the car as normal with the inner window out. If I need to get back in there to re-adjust one or two its easy. Once I am satisfied, then I reinstall the inner window.

Edited February 26, 2023 by keithb7

[Semmerling]

Rick many thanks, much appreciated and confirm my manual as well.

Dave, nobody will ever say that you cut corners. My kinda guy. 

[Semmerling]

Keith would you be so kind as to drop the links right here for those that might follow? Much appreciated. 

[keithb7]

 

[Sniper]

10 minutes ago, Semmerling said:

By and large the best that P15 has to offer is lost because of an abysmal search engine

 

Are you familiar with using DuckDuckGo to do a site specific search?

Use the following link and add your search terms

 

http://site:p15-d24.com

 

For example http://site:p15-d24.com valve lash returns the following

 

 

[Semmerling]

Special thanks to Rick D. for the table

[Semmerling]

Keith and Sniper, many thanks very helpful both..

[Bob Riding]

Not to confuse things, but I just cold-set my valves according to my "1946-1954 Plymouth Service Manual" and it says

 

Cold - intake .010, exhaust .013

Hot -   intake .010, exhaust .010

[Semmerling]

Many thanks for that Bob

 

[FarmerJon]

I have the same plymouth book, as well as a couple other Chrysler printed car books, they all call for no less than .010 on the intake. I have only seen online and motors manuals call for .008 intake. 

I am not saying it won't work, or that Mopar didn't call for it, just that it would be nice to see it from the source.