Cam towers- removal and install on engine FAQ

[Phlebmaster]

This is a write up I did to help a fellow datto brother out.......

 

I have pulled my cam towers off of my L4 head on many occasions, So I thought I would share what works for me.

 

 

The reason not to do it is simple...binding your cam will wear it out the towers and send metal into your motor. Not good at all.

 

But if you are very careful you can put everything back together without incident by doin this:

 

#1. number your rockers in the order they sit in your head. carefully pull the rockers, springs and retainers keeping them as sets.

 

#2. Put your motor at TDC and chock your chain tensioner and pull the cam gear. Don't lose your chain or you will be pulling your timing cover. I use a 1" dowel about 10" long.

 

#3. loosten the 10mm allen head bolts that are holding your towers first

and pull them out. Better be sure you have your torque wrench handy for re-installation. Re-torque can be tricky....you need to snug the head bolts back in first, then go in three to four steps tightening them down.

 

Head bolt re-torque

Try like 10lbs, 15lbs, 20lbs, 35lbs, and no more than the standard torque for the final step. Check your owners book for that last step. Then do a quick check on all head bolts at the top setting, being careful not to over torque them. Iv'e done that.

 

 

 

#4. Now your cam should spin freely. Then take out all of the other cam tower bolts. They are 10mm socket.

 

#5. Pulling the cam towers can be a bit tough at first..use a rubber mallet and tap very gently while you wiggle the cam towers. There will be several inserts that aid in lining up the towers and they get stuck sometimes. Be sure you DO NOT lose any of them. Your cam and towers should lift right off. Mark your towers 1-4!!

 

Re-install

#1. putting everything back in is pretty strait forward...just do the opposite of the steps you took to get it off. If using new cam towers 1-4 according to where they go on the head.

 

#2. Now the tricky part.....getting the towers to line up takes some finesse. If the head is in the car, then you will need to insert the cam into all of the towers making sure you have the right tower on the right cam bearing before you install them. If you don't, you will be pulling them again I promise. Use assembly oil like Lukas or something in the cam towers and on the cam bearing races.

 

#3. line up the cam towers on the head and get the inserts I told you about lined up and gently set them in. Then you take the cam tower bolts and set them in and get them started, but don't tighten them.

 

#4. Now put in your head bolts you pulled and get them started too leaving them loose.

 

#5. The allignment..... now you take your cam and turn it many times as you make the bolts tighter and tighter. This will ensure your allignment and you will know if the towers are off before you finish.

 

#6. once everything is tightened and torqued down, you put your rockers and springs back in. The trick with this part is making sure your cam does not move backward in the towers....keep it lined up!! Line up your timing marks and you are golden. Do not turn your cam with the motor at TDC...otherwise you could bend your valves on the #1 and #4 pistons.

 

Thats about it.

Edited September 15, 2009 by Phlebmaster