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| motor valve adjustment [message #236278] |
Thu, 16 January 2014 10:02  |
skip2
Messages: 544
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Going after the valve seals this weekend and I've heard 2 trains of thought on setting the lash afterwards,one has 16 different positions you have to put the crank and cam at to assure you are on the low spot of the cam and the other was just 2 positions for the crank where you do half then change and do the other half. All my valve adjusting has been with motor running and on vehicles that were already greasy and the leaking oil didn't matter to much. Any experiences with or suggestions would really be appreciated.
Skip Hartline
74 Canyon Lands, FiTech,
3.7 FD LSD, Manny Tranny,
Springfield Distributor,
2001 Chevy Tracker Ragtop Towd
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| Re: motor valve adjustment [message #236294 is a reply to message #236278] |
Thu, 16 January 2014 11:32  |
skip2
Messages: 544
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Forgot to mention it has eldobrock alum heads and crane cam roller rocker arms. Skip
74 Canyon Lands, FiTech,
3.7 FD LSD, Manny Tranny,
Springfield Distributor,
2001 Chevy Tracker Ragtop Towd
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| Re: motor valve adjustment [message #236311 is a reply to message #236294] |
Thu, 16 January 2014 14:25 |
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Matt Colie
Messages: 8547
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Location: S.E. Michigan
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| skip2 wrote on Thu, 16 January 2014 12:32 |
Forgot to mention it has eldobrock alum heads and crane cam roller rocker arms. Skip
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Skip,
Not all Crane roller rockers are adjustable. If yours are, then go ahead.
Yes, you can set every valve on up to an 8 cylinder engine with two crank positions. The chance of missing this is very close to 98% unless you are very familiar with that engine family.
Now, remember I used to write instructions for technicians in a contract lab doing testing on anybodies engines. Because of that and the confusion that things can cause, I developed a means to always get the engine's crank/cam positions correct (if the tech read my directions at all, but that is another story).
This works every time...
Write the firing order as two rows - i.e. Olds 455
(Oldsmobile engines are numbered down the crank and the leading cylinder is #1. Isn't that handy?)
1 8 3 4 <= to set these valves
6 5 7 2 <= set this cylinder in cross-over And Vice-Versa
Next, with either valve gear cover removed, get a cylinder head long stick and put it in proximity to the valve gear and write on it:
I E I E E I E I --- Do I have to say this is the same on both sides? (You only need one of these.)
Now, with both valve gear covers removed, bar the engine until you see an exhaust valve closing. Watch that cylinder's intake. It will start moving just before the exhaust valve stops. You are at crossover (close enough) to set the valves in the other row. (So, if #6 exhaust just closed and intake moved, set valves for #1)
As said, the above method is foolproof (if followed).
This is usually easy to do in the compression can be released (like by removing spark plugs if any - we did diesels - too). Most engines can be "barred" by just pulling on the FEAD belts.
You should be able to check for cross-over by rattling the valve gear on that cylinder. That pair should be tight.
On an American V-8, you will get a chance to adjust valves every 90° degrees.
Matt
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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| Re: motor valve adjustment [message #236328 is a reply to message #236315] |
Thu, 16 January 2014 16:00 |
skip2
Messages: 544
Registered: September 2011
Location: Winter Haven,FL (center o...
Karma: 3
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Matt, I'm pretty sure this is the method I'm looking for but call be DENSE, can you splain with more details, like which valves with which crank position. Thanks
Skip Hartline
74 Canyon Lands, FiTech,
3.7 FD LSD, Manny Tranny,
Springfield Distributor,
2001 Chevy Tracker Ragtop Towd
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| Re: [GMCnet] motor valve adjustment [message #236331 is a reply to message #236325] |
Thu, 16 January 2014 16:11 |
Mr ERFisher
Messages: 7117
Registered: August 2005
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Tis here
http://gmcmotorhome.info/engine.html
FREE WIFI @ Mickey D
On Jan 16, 2014, at 1:33 PM, Matt Colie <matt7323tze@gmail.com> wrote:
>
>
> Larry wrote on Thu, 16 January 2014 15:50
>> Matt Colie wrote on Thu, 16 January 2014 14:25
>>> skip2 wrote on Thu, 16 January 2014 12:32
>>>> Forgot to mention it has eldobrock alum heads and crane cam roller rocker arms. Skip
>>>
>>> Skip,
>>>
>>> This works every time...
>>> Write the firing order as two rows - i.e. Olds 455
>>> (Oldsmobile engines are numbered down the crank and the leading cylinder is #1. Isn't that handy?)
>>> 1 8 4 3 <= to set these valves - corrected
>>> 6 5 7 2 <= set this cylinder in cross-over And Vice-Versa
>>>
>>> Matt
>>
>> Matt,
>> Firing order is:
>>
>> 1843 not 1834 isn't it?
>
> OOps....
> That's why it is on a sticker on my air filter....
> Thanks
>
> Matt
>
> --
> Matt & Mary Colie - Members GMCMI, GMCES Going to MontgomeryThe majestic, once snow covered glacier Chaumière is in for the winter.
> '73 Glacier 23 With 4 Rear Brakes that pull as they should
> SE Michigan - Twixt A2 and Detroit
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| Re: [GMCnet] motor valve adjustment [message #236350 is a reply to message #236331] |
Thu, 16 January 2014 18:41 |
skip2
Messages: 544
Registered: September 2011
Location: Winter Haven,FL (center o...
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All I see the firing order on the info site, am I missing something? Crane cam's site instructs 16 different positions for the cam to be in to set for each of the 16 rocker arms,then adjust to zero slop in push rod plus 1/2 turn more.
I'm looking for an explanation of the 2 crank/cam positions that Matt mentioned. Skip
74 Canyon Lands, FiTech,
3.7 FD LSD, Manny Tranny,
Springfield Distributor,
2001 Chevy Tracker Ragtop Towd
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| Re: [GMCnet] motor valve adjustment [message #236355 is a reply to message #236350] |
Thu, 16 January 2014 18:59 |
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USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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Skip,
I did a Google search for Crane Cam adjustment and found this which I assume is what you're quoting in your message.
http://www.cranecams.com/uploads/instructions/151g_.pdf
Here's the paragraph you need to follow:
Quote:
To adjust preload on hydraulic lifter camshafts with adjustable rocker arms, turn the engine in the normal direction of rotation
until the exhaust lifter starts to move up, then adjust the intake valve to zero lash with no preload, then 1/2 to 1 turn more. Turn
the engine over again until the intake opens completely and then is almost all the way back down. Now, set the exhaust valve to zero
lash, then 1/2 to 1 turn more. Continue the above procedure for each cylinder until all valves are adjusted to the same amount of
preload. This procedure will give you the correct lifter preload for any hydraulic lifter cam with adjustable rocker arms.
Unquote:
If you don't follow this procedure to the letter you could cause serious problems!
Regards,
Rob M.
Sydney, Australia
-----Original Message-----
From: Skip Hartline
All I see the firing order on the info site, am I missing something? Crane cam's site instructs 16 different positions for the cam
to be in to set for each of the 16 rocker arms,then adjust to zero slop in push rod plus 1/2 turn more.
I'm looking for an explanation of the 2 crank/cam positions that Matt mentioned. Skip
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Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
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| Re: [GMCnet] motor valve adjustment [message #236362 is a reply to message #236355] |
Thu, 16 January 2014 20:01 |
Larry
Messages: 2875
Registered: January 2004
Location: Menomonie, WI
Karma: 10
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| Robert Mueller wrote on Thu, 16 January 2014 18:59 |
Skip,
I did a Google search for Crane Cam adjustment and found this which I assume is what you're quoting in your message.
http://www.cranecams.com/uploads/instructions/151g_.pdf
Here's the paragraph you need to follow:
Quote:
To adjust preload on hydraulic lifter camshafts with adjustable rocker arms, turn the engine in the normal direction of rotation
until the exhaust lifter starts to move up, then adjust the intake valve to zero lash with no preload, then 1/2 to 1 turn more. Turn
the engine over again until the intake opens completely and then is almost all the way back down. Now, set the exhaust valve to zero
lash, then 1/2 to 1 turn more. Continue the above procedure for each cylinder until all valves are adjusted to the same amount of
preload. This procedure will give you the correct lifter preload for any hydraulic lifter cam with adjustable rocker arms.
Unquote:
If you don't follow this procedure to the letter you could cause serious problems!
Regards,
Rob M.
Sydney, Australia
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Why couldn't you adjust them the way we did with the SBC rockers of yesteryear.
Run the engine, back off the adjustment until you hear the lifter clatter, then turn in until the clattering stops. Then turn in 1/4 turn at a time, allowing for the engine to recover at each 1/4, until you are 1 full turn in. Do this with rocker covers off, and a spring loaded cloths pin on each rocker to keep the oil from splattering all over. Just seems easier than trying to find the cam base circle at each of the 16 valves.
Just wondering is all....
Larry 
78 Royale w/500 Caddy
Menomonie, WI.
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| Re: motor valve adjustment [message #236372 is a reply to message #236328] |
Thu, 16 January 2014 22:12 |
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Matt Colie
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
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| skip2 wrote on Thu, 16 January 2014 17:00 |
Matt, I'm pretty sure this is the method I'm looking for but call be DENSE, can you splain with more details, like which valves with which crank position. Thanks
Skip Hartline
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Skip,
The reason Crane calls for the one valve at a time it the it is not possible to screw it up, but it is a lot more work than is necessary. And, we found that when people do more work, they make more mistakes.
The idea behind the procedure I wrote (with the corrected firing order) is to use the cross-over (trading exhaust for intake) in the cylinder 360° (one half of a two stroke cycle) from the cylinder of interest to insure that the valves you are adjusting are on the cam's base circle. That is why the two rows of cylinders.
1 8 4 3 The cylinders above are half a cycle from those below.
6 5 7 2 If you get both valves moving in #6, time to set #1
6 5 7 2 And now you do the others......
1 8 4 3
This will require 8 crank positions, not 16.
Yes, if you really know an engine family well you theoretically can set half the valves, roll the crank a full turn and set the other half, but we found it very easy to miss the base circle on one or more followers.
If you need more guidance, get to me directly at matt 7323 tze at g mail dot com. We are in the same time zone, so if we need to talk about it, we can.
Matt
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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| Re: motor valve adjustment [message #236501 is a reply to message #236372] |
Sat, 18 January 2014 10:26 |
LarryInSanDiego
Messages: 336
Registered: September 2006
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The method Matt describes works for all GM V8s of that era except for Cadillac, which numbers it's cylinders differently. With very mild stock cams, it is a safe procedure, but with long duration cams, it's safer to do it one cylinder at a time (every 90*). BMW recommends it this way, except you turn the crank 120* if you're doing a 6 cylinder.
If you have adjustable rockers, like Chevy and Pontiac, you can set them at zero lash on all the valves by feeling when spinning the pushrod with your thumb and forefinger starts having resistance, then tightening whatever fraction of a turn you want for lifter preload. I've even done this with the engine running if you either have rocker clips or cutting out a section of a spare rocker cover by backing off until you hear clicking and tightening until it barely gets quiet, then add whatever preload you prefer. I would set preload at zero in my Trans Am for an extra skosh of lift and duration, but expect intermittent valvetrain noise.
Larry Engelbrecht
San Diego, CA
'73 26' ex-Glacier
TZE063V100319 03/07/73
[Updated on: Sat, 18 January 2014 10:26] Report message to a moderator |
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| Re: motor valve adjustment [message #236517 is a reply to message #236501] |
Sat, 18 January 2014 12:19 |
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Matt Colie
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
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| LarryInSanDiego wrote on Sat, 18 January 2014 11:26 |
The method Matt describes works for all GM V8s of that era except for Cadillac, which numbers it's cylinders differently. With very mild stock cams, it is a safe procedure, but with long duration cams, it's safer to do it one cylinder at a time (every 90*). BMW recommends it this way, except you turn the crank 120* if you're doing a 6 cylinder.
<snip>
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Larry,
The procedure as published was only numbered for a 455 (with the later corrected firing order). As stated, the firing order board and the valve stick are engine are (at least) family specific. In all the years running a contract lab, the only engine the general procedure was not good for were the DD-92s. They don't have intake valves, so there is no crossover to watch and use.
The things that need to be engine specific are the Valve Stick, because valve arrangements vary widely. This stick was to be very interesting on four and five valve engines. Even American V-8s can be confusing. The firing order boards also had the engine description written on them in big letters and the technician was required in the measuring process (we always measured lash before resetting) to indicate which board and stick he used. (But if one was to only work on one family, this would not be necessary.) The firing order board also had a picture with a fan blade (even though we never used them) and a flywheel with the cylinder numbers by the manufacture's method in between.
When you get to work on everybody's engines. You learn early on that there are different ways to number cylinders. While most in-line engines are numbered down the crank from the fan end. Some are numbered from the flywheel. (Industrial duty engines with no fan drive.) V-8s are anybody's guess. Oldsmobile and Cadillac are down the crank which the leading cylinder being #1 so there is an even and an odd bank, but other manufactures number down one side then down the other. (If the leading cylinder is #1, the one opposite and sharing the throw is #5.) Then there are some that are numbered down one side and back up the other. (This means #1 and #8 share the first throw.) But, the killer for me was an engine where the the trailing bank was #1. So the first rod on the crank was NOT #1 and I don't remember where it when from there.
Anybody care to can feel free to copy and utilize the procedure as my employer at that time A: did not renew the copy rights and B: no longer exists at all.
Matt
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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| Re: [GMCnet] motor valve adjustment [message #236601 is a reply to message #236517] |
Sun, 19 January 2014 09:11 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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Have a look at Ford's 'U' code (Vulcan) V-6 numbering system as in the Ranger pickups. It took me a while to figure it out before I got a copy of a manual.
--johnny
________________________________
From: Matt Colie <matt7323tze@gmail.com>
To: gmclist@temp.gmcnet.org
Sent: Saturday, January 18, 2014 1:19 PM
Subject: Re: [GMCnet] motor valve adjustment
LarryInSanDiego wrote on Sat, 18 January 2014 11:26
> The method Matt describes works for all GM V8s of that era except for Cadillac, which numbers it's cylinders differently. With very mild stock cams, it is a safe procedure, but with long duration cams, it's safer to do it one cylinder at a time (every 90*). BMW recommends it this way, except you turn the crank 120* if you're doing a 6 cylinder.
> <snip>
Larry,
The procedure as published was only numbered for a 455 (with the later corrected firing order). As stated, the firing order board and the valve stick are engine are (at least) family specific. In all the years running a contract lab, the only engine the general procedure was not good for were the DD-92s. They don't have intake valves, so there is no crossover to watch and use.
The things that need to be engine specific are the Valve Stick, because valve arrangements vary widely. This stick was to be very interesting on four and five valve engines. Even American V-8s can be confusing. The firing order boards also had the engine description written on them in big letters and the technician was required in the measuring process (we always measured lash before resetting) to indicate which board and stick he used. (But if one was to only work on one family, this would not be necessary.) The firing order board also had a picture with a fan blade (even though we never used them) and a flywheel with the cylinder numbers by the manufacture's method in between.
When you get to work on everybody's engines. You learn early on that there are different ways to number cylinders. While most in-line engines are numbered down the crank from the fan end. Some are numbered from the flywheel. (Industrial duty engines with no fan drive.) V-8s are anybody's guess. Oldsmobile and Cadillac are down the crank which the leading cylinder being #1 so there is an even and an odd bank, but other manufactures number down one side then down the other. (If the leading cylinder is #1, the one opposite and sharing the throw is #5.) Then there are some that are numbered down one side and back up the other. (This means #1 and #8 share the first throw.) But, the killer for me was an engine where the the trailing bank was #1. So the first rod on the crank was NOT #1 and I don't remember where it when from there.
Anybody care to can feel free to copy and utilize the procedure as my employer at that time A: did not renew the copy rights and B: no longer exists at all.
Matt
--
Matt & Mary Colie - Members GMCMI, GMCES Going to MontgomeryThe majestic, once snow covered glacier Chaumière is in for the winter.
'73 Glacier 23 With 4 Rear Brakes that pull as they should
SE Michigan - Twixt A2 and Detroit
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