Cams Won't Turn

[googoogjoob]

I've been working on replacing the headgasket, timing belt, and valve stem seals for about 2 weeks now. I cleaned everything up, put the head back on, but now I can't get the cams to turn. Is it just because there's oil in the lifters from when I soaked them? I thought I read somewhere they would drain by themselves since there's no hole on the top to do it myself.

 

[RadDsm]

Did you put the cam caps back in the correct order?

 

[googoogjoob]

Yeah. How hard is it supposed to be to turn the cams? I haven't pushed too hard trying not to break anything.

 

[Calan]

Did you put the cam caps back in the correct order?

And facing the right direction?

My bet is on the cam caps, but you should definitely bleed the lifters. You should be able to easily push the plunger in by hand after doing so. If you let them sit a day or two after bleeding, check them again before installing...they tend to lock back up if there is any oil left in them.

With the timing belt still uninstalled...

Even if the lifters were somehow locked up completely, the cams should still turn if all the pistons are in the middle of the cylinders. But if two of the pistons are at TDC, the valves could be hitting them and preventing the cams from turning easily.

 

[googoogjoob]

Yep. I definitely made sure. Hard to mess that up when they're numbered and have an arrow and L or R on them. When I looked up how to bleed the 420a lifters there was no real answer. Unlike pretty much every other lifter out there, the 420a's don't have a hole in the top to decompress them to bleed them. Do you know if they'll just drain by themselves? I figured I'd wait a day or so to see if its easier then. I'm pretty sure that's the only thing stopping the cams though. Oh and I made sure the crank was 3 marks before TDC so the pistons weren't interfering.

 

[minimoose]

The cams should turn over by hand but they will be a little strong cause your fighting the valve springs but with both hands you can turn it.

 

[talonDSMerr]

^^ Yup. The cams won't be easy to turn by any means because of the valve springs. Once you get the timing belt on and turn the entire assembly from the crank with a ratchet, it should be much easier (than trying to turn the cam by itself).

 

[Frickadella]

I would back up a step and remove the cam followers. The camshafts should turn freely then with no force required. If they don't, then you have binding on the journals.

Do you have the timing belt properly installed when you are trying to turn the cams? If not, you definitely need to make sure no pistons are at TDC, like calan stated, before you attempt to turn the cams.

Depending on what springs you have on the head, you might be able to turn the cams by hand, but even a 17mm? wrench should turn them.

Even if the lifters were fully pumped up, I'd expect to get some movement on the cam. To compress them, put them in a vice making sure not to damage the the end and SLOWLY compress. It shouldn't take much force. Other than that, sitting under spring pressure in the head will usually compress them overnight or so.

 

[DSM1G90]

Did you do the step torque and tightening procedure per each cap along with the proper loosening procedure?

You might have some caps down too tight from the beginning. Loosen them all up to see if you caan turn the cams for sure...but first, put the crank at 90* from TDC so all of the pistons are dead center in the middle of their bores so you know you won't be smaking valves into the pistons when you turn the cams.

Where he has a 420A motor, it's put together quite different than the 4G63 and has different maintenance procedures.

Good luck-DSM

 

[googoogjoob]

Thanks for the replies. I'm pretty sure it was just because of the springs and oil in the lifters because they turn now, not easily but they do.
I have 2 more questions though. The first is how to get the semi circular cap out of the valve cover. I know the 4G63s have rubber ones but the 420as are alluminum. I can't get it to pry up even with a flat head screw driver or pliers. I'm pretty sure it was leaking there before though so I wanna put new rtv around it.
Also what did you guys use to hold the cams when tightening the sprocket bolts? All I've seen is big channel locks used but I don't have any.
Thanks

 

[IQ685]

Now I'm not sure if the 420a cams are the same, but on a 4g63 there is a place on the cam that a wrench will fit on(it looks similar to a bolt head in the middle of the cam). Put a wrench on that arnd a block of wood or something semi soft between the wrench and the head and use that to rest the wrench on as you tighten the bolts that hold that cam gears.

 

[talonDSMerr]

For the semi-circular cap, you should be able to just yank it off. Clean off the oil and grease so you can get a good grip on it, you're stronger than that old RTV

If not, maybe try using a mallet and a small piece of wood and lightly tap one side so it "rocks" and breaks the RTV seal?

I'm not familiar with the 420A, but 4g cams have hexes on the camshaft that you can use to hold the cam still with either a big wrench or an adjustable wrench. Still yet, if the cam gear allows, you can make a tool like the one pictured below. Look for a hex on the camshaft first, though.

 

[googoogjoob]

I got that semi circular piece off finally. Just had to get a bigger flat head and pry it up. I think hittin it with a mallet helped though.
As for the cams, there's no where to put a wrench on to hold em but I think I can make a tool like the one in the pic. Should help a lot. Thanks for all the good info

 

[95TalonOwner]

2GNT.com - DCR_Cam_Timing_Fixture_and_Dial

To properly hold the cams, you need to make or buy a tool to do it. All you need is a piece of flat stock and two dowel pins. The cams have a hole in them for the dowels. Personally I have never needed it.

 

[googoogjoob]

Just thought I'd update my post with how it all turned out and everything. I couldn't make a tool close enough to the one in that picture but I did manage the keep the cams still by using two bolts and a scrap piece of 2x4. Since there's a hole on each cam that faces up when they're at top dead center, I measured the distance between them, drilled two holes, and put bolts that fit in them. It seemed to work pretty well for me.

 

[FearlessNick]

I just built a 420a motor and you can bleed the lifters... Theirs a little hole on the side of them.

Plus, these 420's are super simple. Did it in like 3 days.