Help setting valves on a 225

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Dartncharger

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Guys, I can't get a straight story on setting the rocker arm/valve clearance on my 1967/225 and I think that's what is causing some grief.
anyway, I was told to spin the crank until the opposing valve starts to depress, then use a feeler gauge and set clearance on the opposite one. Same with all the rest, so is this right? Or do I have to make sure the cam has the valve depressed ALL the way down???

Or is it best to do while it's running?

Confusing as hell.

Any help here?
 
Sorry to disagree Dan, but my in my experience, adjusting the valves with the engine off is far easier. An engine running adjustment is no more accurate than one done on a properly warmed up engine that is shut down. Working on a running engine also has the disadvantage of being potentially quite messy. With a simple understanding of crank spacing and running mates, it is possible to have all valves adjusted in two complete revolutions of the crankshaft (720 degrees) in as little as ten minutes. The amount of metal contraction due to cooling in even 30 minutes of engine off time will not have an appreciable impact on the accuracy of the valve adjustment. This is especially true if you are using feeler blades to do the adjustment, since they lack the accuracy that a dial indicator can provide.

Dartncharger - if you follow the advice of adjusting a valve when "the opposing valve starts to depress" you will have some severe difficulties. I think the person giving the advice was likely referring to using the running mate as a guide to when to adjust. If I may explain a little...

On a 6 cylinder engine, there is one piston coming to the top of its compression stroke every 120 degrees (or 1/3 of a turn) of crank rotation (720 degrees divided by 6). When one piston is at the top on its compression stroke, there is another piston (called its running mate) at TDC also, but it is on the exhaust stroke.

Since at the top of the exhaust stroke, both valves are in motion (during valve overlap) this makes it easy to identify where to adjust the valves on the running mate (the other piston at TDC).

To find running mates, simply write the numbers of the first three cylinders in the firing order (1 - 5 - 3) then draw a line and write the next three in the firing order beneath the first three (6 - 2 - 4). Thus, 1 & 6, 5 & 2, 3 & 4 are running mates. Starting anywhere the engine happened to stop, rotate the engine until you see which exhaust valve is closing. Keep turning until you see the intake valve on the same cylinder start to open. Both valves are now in motion as this is the overlap phase of the camshaft. Call this the rock position. Stop turning the engine over and adjust the valves on the running mate to the one whose valves were both moving. Since these pistons are now at (or close to) TDC, the lifters of the running mate are on the base circle of the cam lobe. Do not worry that you may not be EXACTLY at TDC - a few degrees of crank rotation one way or the other will make absolutely NO difference, as the base circle of the cam lobe covers well over 90 degrees of crank rotation. Once you have adjusted the valves on this cylinder, simply rotate the crank 1/3 of a turn (120 degrees) and adjust the valves on the next cylinder in the firing order.

How do you know you have turned 1/3 turn? The same way as before - watch which exhaust valve is closing and turn the engine over until the intake valve begins to open (rock position) - now adjust the running mate. You will find that you are adjusting the valves on the cylinders following the firing order of the engine, while the valves you are using to guide you are 1/2 rotation behind, but also following the firing order.

Thus you will adjust as follows (assuming cylinder #3 is on the exhaust stroke):
Valves on #3 in the rock position - adjust #4
Turn 1/3 until-
Valves on #6 in the rock position - adjust #1
Turn 1/3 until-
Valves on #2 in the rock position - adjust #5
Turn 1/3 until-
Valves on #4 in the rock position - adjust #3
Turn 1/3 until-
Valves on #1 in the rock position - adjust #6
Turn 1/3 until-
Valves on #5 in the rock position - adjust #2

Finished!

Be as consistent as you can on the amount of feeler blade drag you set the valves with. One thou (0.001") of clearance changes valve timing by almost 4 degrees of crank rotation. Too tight and your valves are opening early and closing late - too loose and the valves open late and close early. This can affect idle quality, power, fuel consumption and emissions. If you set them so tight as to remove all lash altogether, the exhaust valves will overheat (and likely burn) - if the car runs at all. My 1966 Chrysler manual calls for 0.020" on exhaust and 0.010" for intakes - but check a manual for your year to be sure.

If you want true precision, mount a dial indicator such that its plunger is aligned parallel with the valve on the tip of the rocker. This is a little more time consuming and really quite unnecessary however, as you should be able to be as accurate as you need to be using feeler blades. If you can find them, a set of go-no go feeler blades work very nicely. These are a stepped feeler blade with 0.002" difference in the "step" of the blade.
 
You are absolutely right 64SignetConv! Part of my years playing with cars gave me some exposure wrenching on Porsches, as you know valve adjustment on an air cooled motor is even more critical as they call for a valve lash of only .004" cold. Adjusting valves while running is left to Hydraulic lifters only.
 
Whoa, Dan, both you and 64SignetConv presented interesting info about two different opinions on valve-adjustment theory. Both of you offered interesting info, but only you managed to serve up a bunch of attitude.
Maybe reconsider your opinion delivery (regardless of who's correct), because the way I see it--if those guys wanted your lip they'd jiggle their zippers.
 
Sorry you feel offended. Nobody's forcing anybody to read my posts, or to agree with me, or to adjust the valves on a slant-6 engine any particular way. Most of us over on the slant-6 board (including Doug Dutra, who knows more about slant-6s than just about anyone else alive, certainly including myself) adjust 'em running. It works well and doesn't create a mess. Some prefer to adjust 'em with the engine off. Either method works; it's all accordin' to where your boogaloo situation is at, y'dig?
 
Have to agree with Dan here. Setting them while running goes soooo much quicker than stopping to rotate my engine from point to point.

About the heat from the engine making a difference, I manage a machine shop and the temperature of the metal definitely does make a difference. We don't do aerospace work or anything close but have a controlled temperature just for that fact. The metal can expand and contract significantly during hot and cold cycles.

Another good point in adjusting it while running is that you can actually hear the changes that you make. The "clicking" goes away when you get it right and if you go too far , it starts to stumble and the idle changes.

And the mess is not a big oil washout and most times nothing to speak of.

Just my opinion guys.
 
After reading this thread I am sure glad I stayed with V8's or at least stayed away from /6's. Man you guys can be quite "religious" about it, Yikes!

Just because your motors are bent out of place it doesn't mean you have to be. Now be nice and hug. LOL

Peace,
Chuck
 
I have two slants that give me fits with the valve adjustment. I have used the method of the firing order divided for decades successfuly on other engines, but these! Whew.
One car runs great until hot, then a cylinder or two start to slowly drop out as it warms up. I think the valves are too tight. The other slant sound like a ball peen hammer wacking away. Too loose on one.

I am starting to think that the rocker arms are worn recessed to the valve stem. Then the wider feeler gage rides on the sides of the recessed area, giving a false valve adjustment.

The last time I adjusted a running engine was the last time for me. Hot burning oil squirting everywhere. What a mess.

I enjoy the many amusing responses from everyone. The bent slant was very funny!
Glen
 
Actually the slant sixes don't squirt hot oil everywhere. The push rod aren't hollow so they don't squirt. With the idle set down to where it should be for a valve adjustment, they really don't fling but a few droplets of oil anywhere either.

Not really fair to compare V-8(other engines) and slant six.
 
Love all the responses/suggestions/advice.
The mighty 225's valves will be adjusted in the AM right after I pick up a new v/c gasket.
Which way am I doing it? well.....:read2:
 
No offence taken or or intended here - I respect that others "boogaloo" to their own tune!! As I said - just stating my preference based on my experience working in the trade. I have used both methods and made a choice. A quick poll of several of my colleagues (all with well over 25 years experience in the trade) revealed a more or less even split on PREFERRED method - but all agreed the accuracy depends on the man (or woman) with the blade & wrench - not on the method of choice.

My post was NOT meant to imply that there is any flaw or less accuracy in using the engine running method Dan prefers. Dartncharger had requested a little clarification, and some of the info he had was either poorly communicated or simply dead wrong to begin with - my intent was to clarify the procedure he mentioned and provide some justification for my preference.

Valiant1966 - I agree that metal expansion is a factor in valve clearance, but I stand by my statement that the dimension change due to temperature will be insignificant if the procedure is carried out in a timely fashion. In my opinion, there is more inherent inaccuracy in using feeler blades than in 10 minutes of metal cooling.

Engine running or engine off - take your pick Dartncharger. Both methods will work with equal success if done properly.
 
I always adjust the valves on all the 6's we have when running, 12 and 22. It's also pretty easy to do just by ear if you don't have any feeler gauges.
 
Fellas, Again a great discussion! I took some advice from a couple of youz and it turned out just fine.

HEY, any of you remember back in the 60's and 70's when those poor things NEVER got adjusted? You could hear that /6 coming/going down the street from a half block away (almost)
Wonder why it wasn't (easily) corrected??
 
Lazy people! That or people just didn't know any better or care enough to do it. When we took the 66 home after buying it the temp gauge pegged out, the motor almost blew and it would only do 10 MPH on the flats all because the valves were so far out of adjustment. I got it home, let it cool off, adjusted the valves and it ran great!
 
slantsixdan said:
Sorry you feel offended. Nobody's forcing anybody to read my posts, or to agree with me, or to adjust the valves on a slant-6 engine any particular way. Most of us over on the slant-6 board (including Doug Dutra, who knows more about slant-6s than just about anyone else alive, certainly including myself) adjust 'em running. It works well and doesn't create a mess. Some prefer to adjust 'em with the engine off. Either method works; it's all accordin' to where your boogaloo situation is at, y'dig?
Click to expand...

Dan I have to disagree.Youp posted it,therefor people read it accidentally while they are trying to read the rest of the post. It happened to me.....
 
needsaresto said:
Youp posted it,therefor people read it accidentally while they are trying to read the rest of the post.
Click to expand...

In case of accidental exposure-

SKIN or EYES: Flush with plenty of warm water for at least 15 minutes
INGESTION: Do not induce vomiting. Drink several glasses of milk or water.
INHALATION: Move to fresh air.
 
Even though I am replacing my /6 in my 72 Duster for a 360(sorry fellow /6 friends but the /6 in it is shot,if it wasnt I would keep it =\)I decided to try this after reading this thread.I found that it wasnt very hard at all doing it SlantSixDans way.It took awhile to get use to turning the ratchet(which is what I used)while it is jerking up and down while the car is running.It took me 30 mins,since I had to turn off the car once in awhile(it smokes bad from bad rings and didnt feel like chocking,lol)With one hand on the feeler gauge and one to turn the wrench,I just moved the feeler in and out quickly while tightening and loostening the bolt on the rocker arm until I had the correct drag.I found it easier if you have 2 feeler gauge sets,or 2 seperate gauges so you can just use one for the exhaust valve,put it down,pick up the other for the intake valve.And the oil splash is very very minimal,in fact i didnt have any splash at all.Just make sure its at a low idle.And if you remove the valve cover carefully,usually the gasket is still good enough to use again.So do it Dans way,after all,hes not SlantSixDan for nothing,lol.Besides,this is also the way it tells you to adjust them in the tune up books.Do it the way MaMopar recommends and it will be much better.Doing it with the engine off while grunting and turning the crank manually sounds more of a pain in the *** than doing it while the cars running.
My /6 is much quieter now,too bad the rings are bad in it ,but I did learn to adjust valves =) and if I ever do get another /6 car,I will know how to do it and not be nervous.
 
Got to agree with Dan and the "do it running" crowd. I've tried it both ways, and it's way easier, and more exciting, to adjust the running engine. The not running method is also less likely to be as accurate. Just don't wear a tie while leaning over the fan.
 
dont understand why dan is being so defensive,has a bad attitude,and thinks his way is the only way..there should be no arguing about it,you guys posted the procedures that you are comfortable with,now it is dart&chargers decision to make..to me its as simple as trying both ways and seeing which one works best for you..i have and prefer the engine off and cool way,but if someone tells me they did it the motor running way,i am not going to ramp and rave about it..we are here to help one another not argue.so,kiss and make up guys..
 
OK, just to muddy the waters... :-D

There is a third way to set the valves on the slant. It takes advantage of whatever lash ramp you happen to have purchased in your particular path to power, economy, stock running or whatever.


Always set them cold with the 120 degree method. set about .001" loose.

Fire up and warm up like always. Now this is the fun part. Most cam manufacturers stab some pretty arbitrary lash figures at you. Sometimes they work, sometimes they don't.

Loosen the first valve until it starts to develop the louder "Tack" sound of a too loose valve. Measure that valve's clearance. Now tighten it a couple of thousandths. Repeat till all done with all the valves. You'll be able to hear the valves a bit, but you won't have idle misses.

This really helps with performance or strange grind cams. I had to do it with my Erson RV15M-Dutra-RDP cam. I ended up gobs looser than the spec Erson shipped with the cam, but it runs right. I give up a tiny bit of lift that likely doesn't make any difference when the tiny ports of our 170 cubic inch derived head are taken into account. Without serious yet careful work on those ports, high lift doesn't get us very far.

So there you have it. The large diameter of the lifter allows us to adjust to our lash ramps pretty easily with no adverse effects.

3-1/2 cents.

So there! :lol:

CJ
 
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