Valve Lash Adjustment

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fstfish66 said:
did you rotate the motor/cam to the heel/bottom on cam lobe, for each valve ?? before you adjusted the rockers ?? you have to rotate the motor ,,and cam to adjust each rocker,, what type or rockers and push rods do you have ?
if you have bent push rods there is a resone for that,either incorrect push rod length or very high spring tension,and not a compatable push rod,,
you may need to pull a few lifters and inspect the cam and lifters,

can you se if your getting oil to the rockers ?
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We rotated the engine until the rocker went up and stop moving....When the rocker stopped moving at the top we adjusted the lash. When both the intake and the exhaust were closed. Is that right?
 
yes as long as your sure they were closed,and did that same thing for each rocker,,,
 
oh and by the way im running a solid lifter non roller,, using stock 273 adjustable rockers,,just adjusted my rockers as a maintence procedure,after 10 years,, or a little over 7000 miles,,,hardly any adjustemt at all,,

CANT BEAT THE FACTORY STUFF,,
 
either way you are going to have to go back through them so one thing I would do differently is to not use the old spin the pushrod to check for drag method. its good if you have done it a few times and you know how it should feel but for someone new to this it can cause some problems like you ran into. when you go back through them do one rocker at a time. yes its time consuming but it will be very accurate and you shouldn't have to do it again. instead of checking the drag on the pushrod loosen the adjuster after you have the valve shut all the way again and use your finger to hold the rocker against the valve stem then run the adjuster down till it just touches the pushrod. again don't apply any pressure to it because you are then already starting to apply preload and if you top that with your half a turn you could be applying too much and hanging the valve open. once you are back at zero lash then you can apply your half a turn that on most adjusters will equal about .020 preload. fire the motor up and let it run for a couple minutes and see if you still have any chatter. if you do then you can tighten them down a little more but shouldn't take more than 1 full turn total.
 
also keep in mind a few guys running roller cams on here have had the problem of the lifter oil groove coming up out of there bores. if that happens the hyd. will constantly be bleeding down and not be able to pump up properly and that might be something to look into.
 
It's possible the lifters were bled down when you adjusted them and when you fired it up they pumped up and held some valves open. I had that happen once and since then I adjust one set of valves and spin the engine over 15-20 seconds then do the next 2 valves. Spinning it over pumps the lifters back up so you get the adjustment right. Takes a few minutes longer but it makes sure you get them correct.

BTW: Here's a handy chart reference to use when adjusting your valves.

Valve lash adj.jpg
 
wazoo64 said:
It's hydraulic roller and new (1000miles) professional build by Joe Sherman. He said that in theory I shouldn't need to keep adjusting. It's just a little concerning to me as to why one lost it's position.
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Is this a Magnum block? You can only use factory hydraulic roller lifters in a Magnum block. Or did you step up and buy hydraulic roller lifters and cam to retro-fit a non-magnum block? Do you have a parts list? What year is the block? Double check your firing order and your spark plugs too.
 
fishy68 said:
It's possible the lifters were bled down when you adjusted them and when you fired it up they pumped up and held some valves open. I had that happen once and since then I adjust one set of valves and spin the engine over 15-20 seconds then do the next 2 valves. Spinning it over pumps the lifters back up so you get the adjustment right. Takes a few minutes longer but it makes sure you get them correct.

BTW: Here's a handy chart reference to use when adjusting your valves.
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When you say spin the engine over do you mean with the starter or by hand?
 
wazoo64 said:
When you say spin the engine over do you mean with the starter or by hand?
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With the starter. You could never spin it by hand fast enough to make the oil pump do it's job. I use a remote starter button hooked up to the starter relay. You can pick one up at most any auto supply for $10-15.
 
camd64 said:
also keep in mind a few guys running roller cams on here have had the problem of the lifter oil groove coming up out of there bores. if that happens the hyd. will constantly be bleeding down and not be able to pump up properly and that might be something to look into.
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My builder told me that if I have a problem it is most likely with a lifter that is faulty. He has seen them go bad in the past. I am going to readjust the lash per his instructions and if it gets noisy again then we will investigate the lifters.
 
Check them now. You don't have to get it running to do that. That way you can find out How to get it running again. One (or more) of the plugs will clearly look different from the rest. This is most likely the bad cylinder(s). From there you can take the next easy diagnostic step of checking the pushrod. Good pushrods? Next would be most likely a faulty (collapsed ) lifter. Time to take the intake off. Etc..Just a first ( and easy) step in the process of finding the culprit. Good Luck!
 
Plugs are brand new. I thought maybe my rough idle was a plug issue so I changed them first. When that didnt fix the problem I thought we may have overtightened the lash when we made the first adjustment. Then I started chasing the valve lash issue so I need to get the lash dialed in and if I get another noisy valve I will be sure to check the plugs for indicators. Good tip. Thanks.
 
If it was running better before the valve adjustment, they are not adjusted correctly.

When the intake just starts to open, adjust the exhaust.
When the exhaust closes, adjust the intake.

This method works on ALL pushrod engines.


I had posted this info on another thread...it may help you:

You can use this method, it works well. Just remember to set them at zero lash initially, then adjust for actual use after break-in.

Valve adjustment for LA headed engine:
If your engine is assembled already you need to remove all the pushrods (if they are in) and both sets of rockers (obviously) and the spark plugs should be removed.

If you only have one adjustable push-rod length checker, do the intake and then the exhaust (or exhaust then intake, does not matter).

Make sure the cam is on the base circle on the cylinder you are checking and put the adjustable pushrod(s) in place (adjusted shorter than needed) and install your rockers. You only need two on at this time, but you can leave them all on, no matter. Adjust the adjuster screws so they show about 2-3 threads protruding out the bottom of the rocker and lock them in place. If the thread count that the rocker manufacturer suggests is different than what I suggested, go with theirs.

The first thing to look at is the roller tip to valve alignment. The tip should be just inboard of center on the valve at zero lift.( see Valvetrain Geometry sheet below)

If that looks good, you can move on to adjusting the pushrod(s).

Adjust the pushrod(s) to take out all lash. Do not preload the lifter(s).

Have a helper slowly rotate the engine by hand 2 full revs and watch the roller(s) on the valve(s) closely. It should start at just slightly IB of center on the base circle of the cam, roll out to just OB of center at half lift, and end up at just IB of center at full lift.

If this all works out, add .040" to the actual pushrod length. This is the correct length.

If your roller tip is not in the right spot, you either have to shim the rocker shafts up or possibly use lash caps on the valves to get the required geometry. I have never used the lash caps so maybe some of the guys that have could tell you about those, if you require them.

Final adjustment procedure after new pushrod install:
When the intake just starts to open, adjust the exhaust
When the exhaust closes, adjust the intake

also, a quicker method:


This sheet really helps, too:


The same procedure with some hardware changes applies to all pushrod engines. I hope all this info is not overwhelming, but it is important to the life of your engine.
ZDDP is what your cam needs to survive. This can be found at your local auto parts store, Walmart, etc in a little blue bottle...STP Oil Treatment. The store brand is also fine. I use it as an assembly lube and I use it in my old engines on oil changes. Modern engines have roller valvetrains and don't need it as much. Also, modern engines require lighter weight oils because the tolerances are generally tighter. The ZDDP additive will increase and maintain a higher viscosity over the life of the oil.
Most motor oils contain some ZDDP, but in much lower levels than they used to, before cat convertors. ZDDP is not good for convertors so it has been regulated out of motor oil. Generally, most motor oils will contain 400 - 800 PPM of ZDDP. Adding STP will raise that number up to at least three times that.

http://www.forabodiesonly.com/mopar/showthread.php?t=54430
 
Well after going through both side of the valve train we fired it up and it ran perfect......except for one problem. One side was very noisy so we went back through that side and added another 1/4 turn of preload......Still noisy. I am convinced we have a bad lifter or two.
My builder says he has had bad comp lifters.
I am pulling the engine and bringing it back to Joe Sherman. Hopefully no major damage. My luck would require a rebuild.
 
Sounds like your making progress Wazoo. I too have had some bad Comp lifters but they were flat tappets. Got one really bad set then the replacements they sent me worked good at first but after 500 miles started bleeding down bad and rattled in the mornings for about 30 seconds. Finally by 700 miles they wouldn't stop rattling. I took the comp stuff out and put in a Lunati and haven't had a minutes worth of trouble. That was 2 yrs. ago.
 
fishy68 said:
Sounds like your making progress Wazoo. I too have had some bad Comp lifters but they were flat tappets. Got one really bad set then the replacements they sent me worked good at first but after 500 miles started bleeding down bad and rattled in the mornings for about 30 seconds. Finally by 700 miles they wouldn't stop rattling. I took the comp stuff out and put in a Lunati and haven't had a minutes worth of trouble. That was 2 yrs. ago.
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Yeah I have heard good things about the voodoo cams. I only went with this roller setup because the builder uses comp exclusively. When it pulled 570HP on his dyno I was glad with the choice. We'll see what the results are in a month or so when I can get the engine back in the builders hands.
 
wazoo64 said:
Yeah I have heard good things about the voodoo cams. I only went with this roller setup because the builder uses comp exclusively. When it pulled 570HP on his dyno I was glad with the choice. We'll see what the results are in a month or so when I can get the engine back in the builders hands.
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Yeah Comp cams do work good. I heard they just had a bad run of lifters for awhile but have it straightened out now. I will say their customer service was good to work with.
 
So my engine builder took the pan off and said the oil looks horrible and thinks it is the root cause of the lifter problems.
Before these lifters started giving me problems I had a carb bowl flooding and he thinks that's what ruined the oil.
The gas washed the carbon into the oil which diluted and soiled the oil.....I had no idea this was possible but he builds the engine pretty loose and I am sure this has a lot to do with why so much gas went into the oil.
Hopefully there is not any major damage caused from running the engine with dirty oil. The engine only has 1500 miles on it. What a mess!
 
alll these problems and it ends up being gas in your oil,,,well it could of been worse,,
 
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