C2 Valve adjustment
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 30
Likes: 1
C2 Valve adjustment
Hi again
I have some difficulties about my C2 engine, one side of the block is not running ok as the other one. I think it can be from the valve adjustment. Does anyone can give me some help with valve adjustment of the engine?
Thanks a lot
I have some difficulties about my C2 engine, one side of the block is not running ok as the other one. I think it can be from the valve adjustment. Does anyone can give me some help with valve adjustment of the engine?
Thanks a lot
Team Owner
Joined: Nov 2005
Posts: 28,223
Likes: 2,872
From: Beach & High Desert Southern California
Hydraulic lifters just need the rocker nuts loosened with the engine running until they make noise, and then tightened until noise goes away with about 1/8 of a turn tighter for wear clearance.
Solid lifters need to be adjusted to a specific lash or clearance specification. Typical stock cams are the 097 (Duntov, or 0.008-0.018) cam, the 30-30 (0.030-0.030) cam, and the LT1 (0.024-0.030) cam (lash clearance in thousands of an inch between the rocker arm tip and the valve stem, Intake-Exhaust).
No cam lash is set in stone. Lash can vary plus or minus 0.000 to 0.015 from the stock GM specifications depending on the cam. GM gentle cam lobe profiles are very forgiving to adjustment. Tighter lash usually benefits higher rpm, loose lash usually benefits lower rpm performance.
Some aftermarket solid lifter cams with faster lobe profile ramp rates need more care with lash, to prevent damage from lifter/lobe contact abuse.
John Hinkley & SWC Duke provide one method to adjust lash, to assure you have the lifters on the base circle of the cam. There is probably a link to this in the FAQ sticky, but Google popped this link.
corvette-30-30-and-other-oem-sb-solid-lifter-cam-valve-adjustment/
Race Director
Joined: Apr 2005
Posts: 11,277
Likes: 2,139
From: Bowling Green, Kentucky
That won't help us............
Need year of car and engine, engine cu in displacement, and horsepower rating. Also if engine has been modified, and if cam is hydraulic or solid lifter (or roller lifters).
Then we can assist.
Larry
Need year of car and engine, engine cu in displacement, and horsepower rating. Also if engine has been modified, and if cam is hydraulic or solid lifter (or roller lifters).
Then we can assist.
Larry
Team Owner
Joined: Aug 2007
Posts: 58,061
Likes: 7,146
Army
CQ suffix is a base 230hp 283ci C1 mill - hydraulic lifters in original trim...
You can buy oil diffusers or else cut up a set of valve covers to adjust the valves. With the engine hot and running back off the adjustment nut (while listening, keep pressure OFF the wrench/socket to let the lifter work freely) until you hear clatter...then tighten things up 3/4 to 1 full turn, pausing at each 1/4 turn to let the lifter stabilize. I don't know anybody that adjust hydraulics only 1/8 turn from zero lash...
Here are oil diffusers.. http://www.jegs.com/i/Mr.+Gasket/720/1015/10002/-1
PLEASE NOTE: Valve adjustment may have nothing to do with one of your engine banks running poorly....could be plug wires, plugs, carb, leaky intake, and, on and on...
You can buy oil diffusers or else cut up a set of valve covers to adjust the valves. With the engine hot and running back off the adjustment nut (while listening, keep pressure OFF the wrench/socket to let the lifter work freely) until you hear clatter...then tighten things up 3/4 to 1 full turn, pausing at each 1/4 turn to let the lifter stabilize. I don't know anybody that adjust hydraulics only 1/8 turn from zero lash...
Here are oil diffusers.. http://www.jegs.com/i/Mr.+Gasket/720/1015/10002/-1
PLEASE NOTE: Valve adjustment may have nothing to do with one of your engine banks running poorly....could be plug wires, plugs, carb, leaky intake, and, on and on...
Last edited by Frankie the Fink; Feb 5, 2016 at 01:55 PM.
Drifting
Joined: Dec 2009
Posts: 1,388
Likes: 65
From: Sugar Land tx
CQ suffix is a base 230hp 283ci C1 mill - hydraulic lifters in original trim...
You can buy oil diffusers or else cut up a set of valve covers to adjust the valves. With the engine hot and running back off the adjustment nut (while listening, keep pressure OFF the wrench/socket to let the lifter work freely) until you hear clatter...then tighten things up 3/4 to 1 full turn, pausing at each 1/4 turn to let the lifter stabilize. I don't know anybody that adjust hydraulics only 1/8 turn from zero lash...
Here are oil diffusers.. http://www.jegs.com/i/Mr.+Gasket/720/1015/10002/-1
PLEASE NOTE: Valve adjustment may have nothing to do with one of your engine banks running poorly....could be plug wires, plugs, carb, leaky intake, and, on and on...
You can buy oil diffusers or else cut up a set of valve covers to adjust the valves. With the engine hot and running back off the adjustment nut (while listening, keep pressure OFF the wrench/socket to let the lifter work freely) until you hear clatter...then tighten things up 3/4 to 1 full turn, pausing at each 1/4 turn to let the lifter stabilize. I don't know anybody that adjust hydraulics only 1/8 turn from zero lash...
Here are oil diffusers.. http://www.jegs.com/i/Mr.+Gasket/720/1015/10002/-1
PLEASE NOTE: Valve adjustment may have nothing to do with one of your engine banks running poorly....could be plug wires, plugs, carb, leaky intake, and, on and on...
Team Owner
Joined: Aug 2007
Posts: 58,061
Likes: 7,146
Army
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Team Owner
Joined: Nov 2005
Posts: 28,223
Likes: 2,872
From: Beach & High Desert Southern California
CQ suffix is a base 230hp 283ci C1 mill - hydraulic lifters in original trim...
You can buy oil diffusers or else cut up a set of valve covers to adjust the valves. With the engine hot and running back off the adjustment nut (while listening, keep pressure OFF the wrench/socket to let the lifter work freely) until you hear clatter...then tighten things up 3/4 to 1 full turn, pausing at each 1/4 turn to let the lifter stabilize. I don't know anybody that adjust hydraulics only 1/8 turn from zero lash...
Here are oil diffusers.. http://www.jegs.com/i/Mr.+Gasket/720/1015/10002/-1
PLEASE NOTE: Valve adjustment may have nothing to do with one of your engine banks running poorly....could be plug wires, plugs, carb, leaky intake, and, on and on...
You can buy oil diffusers or else cut up a set of valve covers to adjust the valves. With the engine hot and running back off the adjustment nut (while listening, keep pressure OFF the wrench/socket to let the lifter work freely) until you hear clatter...then tighten things up 3/4 to 1 full turn, pausing at each 1/4 turn to let the lifter stabilize. I don't know anybody that adjust hydraulics only 1/8 turn from zero lash...
Here are oil diffusers.. http://www.jegs.com/i/Mr.+Gasket/720/1015/10002/-1
PLEASE NOTE: Valve adjustment may have nothing to do with one of your engine banks running poorly....could be plug wires, plugs, carb, leaky intake, and, on and on...
The least amount of lash take up on a hydraulic lifter will provide the least amount of lifter pump up at high rpm. The minimal lash allows the piston in the lifter to have more travel to move without floating a valve. The performance limits of a hydraulic lifter can be improved a few hundred rpm from the minimal lash. The tradeoff is wear adjustments are needed more often than 100,000 mile intervals.
With proper lash I could run 6800-7000 rpm with a hydraulic lifter in one of my Pontiacs. In Stock eliminator where the only choices are hydraulic lifters every bit of rpm helped.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
Frankie, thank you for the correction, 3/4 turn from noise is probably better if the owner never wants to go back and adjust lash again.
The least amount of lash take up on a hydraulic lifter will provide the least amount of lifter pump up at high rpm. The minimal lash allows the piston in the lifter to have more travel to move without floating a valve. The performance limits of a hydraulic lifter can be improved a few hundred rpm from the minimal lash. The tradeoff is wear adjustments are needed more often than 100,000 mile intervals.
With proper lash I could run 6800-7000 rpm with a hydraulic lifter in one of my Pontiacs. In Stock eliminator where the only choices are hydraulic lifters every bit of rpm helped.
The least amount of lash take up on a hydraulic lifter will provide the least amount of lifter pump up at high rpm. The minimal lash allows the piston in the lifter to have more travel to move without floating a valve. The performance limits of a hydraulic lifter can be improved a few hundred rpm from the minimal lash. The tradeoff is wear adjustments are needed more often than 100,000 mile intervals.
With proper lash I could run 6800-7000 rpm with a hydraulic lifter in one of my Pontiacs. In Stock eliminator where the only choices are hydraulic lifters every bit of rpm helped.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
And assuming that your oil pressure is still OK....and the engine has not been sittign for a LONG time.
The reason I am mentioning all of this is that there are some cases that I have encountered (3 times in 30 years) where the lifter plunger was stuck in the down position and I could see it when I got the engine into correct position and loosened the nut on the rocker arm.
SO...due to not being there listening to the noise...I have no idea...but it is something WORTH looking into when you have the valve cover off. I assume NOTHING....because if you take up the slack to get the noise to go away....and the lifter is NOT doing what it is designed to do...you will have more problems than just a noise to worry about.
DUB
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 30
Likes: 1
Thanks, but i found the problem, the last owner have glue a spark plug, that is why the engine was not running well in one side.
But from the passenger side above the starter there is a hole where you can see the engine, what is used to close that hole? Silicon?
And just another thing, when the engine is running parked after some time he puts water out, but if you are running with the car it is ok, what it could be?
Thanks
But from the passenger side above the starter there is a hole where you can see the engine, what is used to close that hole? Silicon?
And just another thing, when the engine is running parked after some time he puts water out, but if you are running with the car it is ok, what it could be?
Thanks
Assuming that the side of the engine that is making noise is still getting oil on the top end of that side.
And assuming that your oil pressure is still OK....and the engine has not been sittign for a LONG time.
The reason I am mentioning all of this is that there are some cases that I have encountered (3 times in 30 years) where the lifter plunger was stuck in the down position and I could see it when I got the engine into correct position and loosened the nut on the rocker arm.
SO...due to not being there listening to the noise...I have no idea...but it is something WORTH looking into when you have the valve cover off. I assume NOTHING....because if you take up the slack to get the noise to go away....and the lifter is NOT doing what it is designed to do...you will have more problems than just a noise to worry about.
DUB
And assuming that your oil pressure is still OK....and the engine has not been sittign for a LONG time.
The reason I am mentioning all of this is that there are some cases that I have encountered (3 times in 30 years) where the lifter plunger was stuck in the down position and I could see it when I got the engine into correct position and loosened the nut on the rocker arm.
SO...due to not being there listening to the noise...I have no idea...but it is something WORTH looking into when you have the valve cover off. I assume NOTHING....because if you take up the slack to get the noise to go away....and the lifter is NOT doing what it is designed to do...you will have more problems than just a noise to worry about.
DUB
Team Owner
Joined: Aug 2007
Posts: 58,061
Likes: 7,146
Army
Wow - struggling with the language barrier. Not sure what 'hole' above the starter you are referring to. If it is a square plug or a petcock, its the block engine drain...any good sealant (or better yet some anti-seize) should seal it.
If your car is emitting coolant when parked, after being driven, you may have too much coolant in it and it is just pushing out the excess. It should stop after a while and the coolant level in the expansion tank settle down to about 1/2 full.
If your car is emitting coolant when parked, after being driven, you may have too much coolant in it and it is just pushing out the excess. It should stop after a while and the coolant level in the expansion tank settle down to about 1/2 full.
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 30
Likes: 1
Thanks. About the languafe barrier i think you understand. Thanks a lot.
Wow - struggling with the language barrier. Not sure what 'hole' above the starter you are referring to. If it is a square plug or a petcock, its the block engine drain...any good sealant (or better yet some anti-seize) should seal it.
If your car is emitting coolant when parked, after being driven, you may have too much coolant in it and it is just pushing out the excess. It should stop after a while and the coolant level in the expansion tank settle down to about 1/2 full.
If your car is emitting coolant when parked, after being driven, you may have too much coolant in it and it is just pushing out the excess. It should stop after a while and the coolant level in the expansion tank settle down to about 1/2 full.