Valvetrain clearance question
Valvetrain clearance question
I am pretty sure I have some excess slack between my cam and the shims. I read that you measure this with a feeler gauge and then replace the shims with thicker/thinner ones, right? First, where can I get a feeler gauge, Sears? What is it exactly? Second, how do you repalce the shims? Are they expensive? What do I tell the dealer I need? Thanks a lot.
A feeler gauge and plasti gauge are 2 differenet things. A Feeler gauge is a tool that has several different thickness blades that rotate out from the main body.
How you do it is you pick a size closest to the spec listed on your under hood label or in the service manual.
Get the engine hot, shut it down and pull the valve cover off.
Rotate you engine by hand or if you have a remote starter hooked up you tap it till the cam lobe is away from the valve shim you want to measure. You then stick the feeler gauge between the shim and cam. If you can slide it in and feel the gauge drag between the 2 with out getting stuck that is your valve clearance.
If you stick the gauge in and it freely slides under the cam with no effort you need to select the next size up feeler gauge and try again till you find the one that drags with out getting stuck.
If you try try to stick it in and it wont go in or it gets stuck you need to select the next size down and try again untill you find one that will slide in and not get stuck but have a bit of drag.
Now if you find that any of these are more then .002in out you now need to remove the shim and use a micrometer to measure the thickness of the shim that is already in there. You take that number and add if too loose or subtract if to tight to it the amount you need to aquire the proper feeler gauge measurement.
So The shim you would be ordering would be what ever number you came up with after you added or subtracted.
Hint: you can sometimes switch shims around to aquire the right setting. This is true if say you had 2 shims out of spec 1 was too tight and 1 was too loose maybe if you swapped those 2 you would aquire the right feeler gauge thickness.
Here the trick to this now there is a special tool used to push the valve down below the cam so you can get the shims out without removing the cam shaft. I dont know if its available after market but we have one at the dealer. it has a curved end on each end that sits on the lip of the shim bucket just out side the shim and rocks against the cam shaft to push down ward force on the shim bucket. We simply call it a shim tool. You could ask around about it at local tool stores and see if they have one available. I will pull a picture of it from the service manual so you will know what your looking for.
How you do it is you pick a size closest to the spec listed on your under hood label or in the service manual.
Get the engine hot, shut it down and pull the valve cover off.
Rotate you engine by hand or if you have a remote starter hooked up you tap it till the cam lobe is away from the valve shim you want to measure. You then stick the feeler gauge between the shim and cam. If you can slide it in and feel the gauge drag between the 2 with out getting stuck that is your valve clearance.
If you stick the gauge in and it freely slides under the cam with no effort you need to select the next size up feeler gauge and try again till you find the one that drags with out getting stuck.
If you try try to stick it in and it wont go in or it gets stuck you need to select the next size down and try again untill you find one that will slide in and not get stuck but have a bit of drag.
Now if you find that any of these are more then .002in out you now need to remove the shim and use a micrometer to measure the thickness of the shim that is already in there. You take that number and add if too loose or subtract if to tight to it the amount you need to aquire the proper feeler gauge measurement.
So The shim you would be ordering would be what ever number you came up with after you added or subtracted.
Hint: you can sometimes switch shims around to aquire the right setting. This is true if say you had 2 shims out of spec 1 was too tight and 1 was too loose maybe if you swapped those 2 you would aquire the right feeler gauge thickness.
Here the trick to this now there is a special tool used to push the valve down below the cam so you can get the shims out without removing the cam shaft. I dont know if its available after market but we have one at the dealer. it has a curved end on each end that sits on the lip of the shim bucket just out side the shim and rocks against the cam shaft to push down ward force on the shim bucket. We simply call it a shim tool. You could ask around about it at local tool stores and see if they have one available. I will pull a picture of it from the service manual so you will know what your looking for.