Valve adjustment question

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SirRobyn0

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I've tried two different ways to adjust the valves (the service manual version twice). When I did the first one it wouldn't start and I thought I'd over tightened, so I remove the cover and do it again, but a little looser. No change. According to the service manual both valves on a cylinder are closed when spark takes place, so I don't think the distributor could be backwards 180*. When I used the cut cap I had the spark plugs out and verified the pistons were at the top of their stroke before adjusting the lash. Now I wish I'd have just left them alone and put up with the ticking noise. I'll eventually get it figured out though.
That's one of the things that I don't like about adjusting valves. Especially if I'm turning them quite a bit, I'll be overly conservative to make sure it starts and none hang open enough to potentially cause a burnt valve. I know this doesn't help you now but in the future, write down for each valve how much additional you turn the valve, and be conservative. It's easier to tighten them further if needed. Then if you have an issue you can undo it, and have some re-assurance that the worst thing that will happen is you'll still have noise. If you think they are some how over tightened, you can always go in and loosen them up some. And attempt a brief start with the cover off. IDK if you have any idea how much additional you tightened them. It's a thought anyway.
 

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The manual says to turn them an additional 3/4 turn. Some say a full turn. This last time I went 1/2 turn. Might have to hit up a mechanic friend who goes to the same church I do. Or talk a friend of mine named Rob who lives across the state in the woods of western Washington to come visit . ;)
 

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Man i would 100% spin that distributor 180 degrees. Remember even though you had #1 at TDC, you still have to be on the compression stroke. I would bet if you do that it will fire up.
 

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The manual says to turn them an additional 3/4 turn. Some say a full turn. This last time I went 1/2 turn. Might have to hit up a mechanic friend who goes to the same church I do. Or talk a friend of mine named Rob who lives across the state in the woods of western Washington to come visit . ;)
I was about to make joke about oh, that's my name and then I realized you were talking about me! Hey, thanks and back at you my friend. The only trouble with that is I have no current plans to be in your area anytime soon. If that changes I'll message you and I'd be happy to come by and take a look.
 

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This is why I went to the method I posted the video on earlier in this thread. Seriously. I have never had an issue doing it that way and it always turns out well and no valvetrain noise at all. You never have to worry about making a mess and no need to set anything to TDC or look at the distributor.

Just pull both valve covers, hook up a starter button, and go to town one cylinder at a time. It makes it a 5-10 minute job once you hook up the button and pull the covers. Maybe 30 minutes total.

Also, I've always done 1/4-1/2 turn after zero lash. 3/4-1 turn seems like way too tight to me.
 

SirRobyn0

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This is why I went to the method I posted the video on earlier in this thread. Seriously. I have never had an issue doing it that way and it always turns out well and no valvetrain noise at all. You never have to worry about making a mess and no need to set anything to TDC or look at the distributor.

Just pull both valve covers, hook up a starter button, and go to town one cylinder at a time. It makes it a 5-10 minute job once you hook up the button and pull the covers. Maybe 30 minutes total.

Also, I've always done 1/4-1/2 turn after zero lash. 3/4-1 turn seems like way too tight to me.
I agree with zero lash + 3/4 - 1 turn being to tight. 3/4 - 1 turn from where it was at might be ok depending on where zero lash falls in that. I will say that this is where I end up not taking enough out and having to remove the cover a second time. If I don't find zero lash in 1/2 a turn I get nervous and won't go much past it. And while I think doing them running is impractical the big advantage would be knowing your not to tight or to loose for certain.
 

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I agree with zero lash + 3/4 - 1 turn being to tight. 3/4 - 1 turn from where it was at might be ok depending on where zero lash falls in that. I will say that this is where I end up not taking enough out and having to remove the cover a second time. If I don't find zero lash in 1/2 a turn I get nervous and won't go much past it. And while I think doing them running is impractical the big advantage would be knowing your not to tight or to loose for certain.
Step one in adjusting valves for me is to back everything WAY out. I don't just back everything off to zero lash and then start adjusting. I start with everything all the way loose, then go through and adjust them into spec one at a time. That way I know they were all started from a known condition
 

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I'm going to throw a curveball into the thread, and I'm curious as to the outcome.

I have done as you kids have done, tighten 1/2 to 3/4 turn max so I am at ease I didn't tighten too much, and I am tired of the valve clatter I still get.
Sometimes 1 full turn does seem too much.
Can never seem to find a happy medium so far.

According to the factory manual, and several members of our forum who worked in the factory, valves are to be adjusted with the cylinder at TDC, both valves closed.
Tighten the nut as you spin the pushrod, when it won't spin any more, tighten one turn more.

Here's the potential curveball, is that with the lifters dry, or the same if they have been run and have oil in them?

AND, since I like to smear assembly lube on the pushrod ends and rockers when I assemble an engine, will that affect the amount of nut tightening until the pushrod stops spinning as opposed to a dry pushrod and rocker ?
 

SirRobyn0

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I'm going to throw a curveball into the thread, and I'm curious as to the outcome.

I have done as you kids have done, tighten 1/2 to 3/4 turn max so I am at ease I didn't tighten too much, and I am tired of the valve clatter I still get.
Sometimes 1 full turn does seem too much.
Can never seem to find a happy medium so far.

According to the factory manual, and several members of our forum who worked in the factory, valves are to be adjusted with the cylinder at TDC, both valves closed.
Tighten the nut as you spin the pushrod, when it won't spin any more, tighten one turn more.

Here's the potential curveball, is that with the lifters dry, or the same if they have been run and have oil in them?

AND, since I like to smear assembly lube on the pushrod ends and rockers when I assemble an engine, will that affect the amount of nut tightening until the pushrod stops spinning as opposed to a dry pushrod and rocker ?

"Here's the potential curveball, is that with the lifters dry, or the same if they have been run and have oil in them?" Ah, ha I wondered when someone would bring that up. SBC is suppose to be adjusted cold, but like you I have heard different things, everything from fire it up for a few seconds, to crank it over until oil pressure is built to no don't do that. I have no idea what the factory service manual says. What I think. Dry, as in no cranking or run time, but also it might not really matter. Here is why I think that. lifter full off oil or not, you want the push rod to push the top part of the hydraulic lifter pad down a tiny bit. Once fired up the oil pressure prevents the lifter from collapsing. But what happens if a guy tries to adjust a valve and the lifter is simply bad well certainly the lifter will still be noisy but is there risk of holding the valve open IDK. I've been around in repair for a good long time but I'm not an engine builder at all. Kevin, I'm sorry I did not answer your question really at all but wanted to throw out my thoughts out anyway.
 

mtnmankev

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"Here's the potential curveball, is that with the lifters dry, or the same if they have been run and have oil in them?" Ah, ha I wondered when someone would bring that up. SBC is suppose to be adjusted cold, but like you I have heard different things, everything from fire it up for a few seconds, to crank it over until oil pressure is built to no don't do that. I have no idea what the factory service manual says. What I think. Dry, as in no cranking or run time, but also it might not really matter. Here is why I think that. lifter full off oil or not, you want the push rod to push the top part of the hydraulic lifter pad down a tiny bit. Once fired up the oil pressure prevents the lifter from collapsing. But what happens if a guy tries to adjust a valve and the lifter is simply bad well certainly the lifter will still be noisy but is there risk of holding the valve open IDK. I've been around in repair for a good long time but I'm not an engine builder at all. Kevin, I'm sorry I did not answer your question really at all but wanted to throw out my thoughts out anyway.
I have been building engines for decades, and up until recently I always adjusted them with the engine running as part of my old school method of tuning every aspect of an engine by ear.
The last engine I did, I tried the "spin the pushrod until it stops turning, then go one full turn on the nut" as the engine was being assembled, didn't want to deal with the mess as it wasn't my truck.
The lifters didn't have any oil in them, and I refuse to do a dry assembly without lube, so I lubed the pushrods and rockers and took my time spinning the pushrods and tightening the nut.
That engine turned out real good, no issues.
This curveball I threw in is one I have never seen discussed on a forum, and nobody has ever been able to give me a definitive answer, so maybe it's every man on his own and see what works for him and what doesn't.
And don't be surprised If I live long enough, I will throw a few more curveballs into the fray on threads.
 

Bextreme04

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I'm going to throw a curveball into the thread, and I'm curious as to the outcome.

I have done as you kids have done, tighten 1/2 to 3/4 turn max so I am at ease I didn't tighten too much, and I am tired of the valve clatter I still get.
Sometimes 1 full turn does seem too much.
Can never seem to find a happy medium so far.

According to the factory manual, and several members of our forum who worked in the factory, valves are to be adjusted with the cylinder at TDC, both valves closed.
Tighten the nut as you spin the pushrod, when it won't spin any more, tighten one turn more.

Here's the potential curveball, is that with the lifters dry, or the same if they have been run and have oil in them?

AND, since I like to smear assembly lube on the pushrod ends and rockers when I assemble an engine, will that affect the amount of nut tightening until the pushrod stops spinning as opposed to a dry pushrod and rocker ?
It doesn't matter. That stuff is only on there for the initial assembly. You set it close enough to run right for initial break-in and then it gets shut down and let cool down. Then I always come back the next day and pull the valve covers and redo the adjustment. By then everything has worn off and broken in. Now do the procedure as shown in the linked video above and that's it. I've never had noisy lifters or an issue at all when done that way.
 

SirRobyn0

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I have been building engines for decades, and up until recently I always adjusted them with the engine running as part of my old school method of tuning every aspect of an engine by ear.
The last engine I did, I tried the "spin the pushrod until it stops turning, then go one full turn on the nut" as the engine was being assembled, didn't want to deal with the mess as it wasn't my truck.
The lifters didn't have any oil in them, and I refuse to do a dry assembly without lube, so I lubed the pushrods and rockers and took my time spinning the pushrods and tightening the nut.
That engine turned out real good, no issues.
This curveball I threw in is one I have never seen discussed on a forum, and nobody has ever been able to give me a definitive answer, so maybe it's every man on his own and see what works for him and what doesn't.
And don't be surprised If I live long enough, I will throw a few more curveballs into the fray on threads.
"And don't be surprised If I live long enough, I will throw a few more curveballs into the fray on threads." I hope so, I enjoy these sort of discussions.

I guess I should say that I have done my share of top engine assembly / disassembly, generally in the vehicle for a head job (with someone else performing the actual valve work), or for lifter or cam replacement ect. On stock or mostly stock motors, but I do not at all consider myself to be an expert or to know the best way where it comes to that stuff. With that said I wouldn't even consider putting anything together inside an engine without assembly lube.
 

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Sorry it's been so long getting back to this thread. Been doing a lot of reading, and watching videos. I decided to back up and go a different route. I bought a remote starter to confirm cylinder #1 at the top of it's compression stroke at TDC. I pulled the spark plug, hooked up the remote starter, put my finger in the spark plug hole, and cranked it over. When I got compression I stopped and looked at the timing mark. TDC. I looked at the rotor and it was pointed at #6 !!!! Or what I thought was #6. It's starting to make sense now. I had installed new plugs and plug wires and I suspect I installed the wires in the reverse order. This distributor has a cap that is numbered and attaches to the top of the distributor (see attached picture). I think I had it reversed when I attached it to the distributor. I corrected it and tried starting the engine. Nothing. I think I need to go back and readjust the valves because I think I did them backwards before. If I'm still on the wrong track let me know.

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mtnmankev

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@CRM Do you have a crankshaft bolt in the harmonic balancer?
If you have the valve cover off to adjust the valves, remove the spark plugs to eliminate resistance, and put a breaker bar and socket on the harmonic balancer bolt, rotate clockwise as you face the engine.
Watch the valves open and close, and when you see both intake and exhaust for the cylinder you're doing go through their cycle and are both closed, adjust that cylinder.
If memory serves me right, your firing order should be 1 5 3 6 2 4 so tighten the valves in that order.
While you have the balancer at TDC #1, make sure the distributor is in and seated to point to #1 on the cap when it would be installed.
I hope this doesn't confuse you, I tried to make it as simple as possible so anybody should be able to do the task and get the engine running right.
 

CRM

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Thanks. That's one of two different ways I've done the adjustment. I've messed things up pretty good I suspect. I'm patient though, and look forward to figuring it out. Kinda fun actually. LOL
 

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