Hi Everyone,

I haven't been able to find the answer for this. I'm changing my spark plugs this weekend and I also bought a bore scope I want to try out since I'll have the plugs out. How do I get the piston at BDC for the best view? Do I simply put it in gear, put a lug bolt back in and turn the hub & use trial and error? I'll have it on jack stands with the rear tires off.

I know that it's better to do this from the oil pan but that's not what I'm doing this weekend.

 

Hey think I can help you out ! First take all your plugs out so you have no compression in the engine , then use a 24mm socket and wrench and use that on the crank pulley but, turn it clockwise to move the pistons, only clockwise !
Use your camera to look inside each cylinder some will be down and others will be up, take a look at the ones you can see into then move the crank pulley to move the pistons which were at the top to the bottom , if you have a piston which is at the top, a half rotation on the crank will see it go down to the bottom, I'm sure someone will probably have worked out the crank pulley position to give you BDC (bottom dead centre) on each cylinder but I don't have that sorry and good luck!

 

Thanks for the help. Some questions: I was hoping to do this one plug at a time. Is it necessary to take all the plugs out at once for this? Which one is the crank pulley? I assume it's the lowest one in the center. Is it accessible without taking the bumper off? I've only had the car 2 months so I'm still learning.

 

Not as elegant but works: I took all spark plugs out, pulled the fuel pump fuse and rotated the engine with the starter. Takes a few tries before you get the piston in a good location.
I believe you need to take all plugs out before turning, otherwise it will be difficult because of the compression in the cylinder.

 

Yes take all the plugs out if you can do that when you turn the engine it won't have any compression to make it harder, crank pulley the big gold one at the bottom, you should be able to take air box out and have decent access, might be helpful to take bumper off to get plugs out though!

 

Use a wrench on the crankshaft bolt. It will be a lot easier when all the spark plugs are out but it isn't necessary.

 

15/16ths wrench.

 

Well, if you are going to scope, you should do the bottom too - by taking the sump plate off. With the crank and rod bottoms visible, you can easily see TDC and BDC.

Top and bottom both is the proper way to scope.

 

You don’t need to pull the bumper to get to the crank pulley.
You can easily do it from up top once the air intake is removed.
You might be able to do it from the bottom without removing anything.
I’m not certain though.

 

I realize that but this is one of those "while the plugs are out" things. The oil pan is not coming off this weekend.