I’m pondering whether to install the head on my '94 without the cams and then install the cams and head bolts. #1 is as TDC and cams will have notches pointing up with tool.My concern is the valves that protrude (interference engine) - handling the head and possibly resting it on the way to the car from the bench etc. I will be using old bolts for guides.
Pros & Cons?
Gary
Gary, when I did the head gasket job in Sept. of 2009, I left the cams in place and put the head on a thick foam. If I had to do this job again, I’d remove the cams before getting the head off the block.
That’s too funny Joe. My head is on exactly the same type of foam. There is a rectangle cut out in the bottom for the valves that protrude.and the surface has been skimmed. I removed the cams before taking the head off.
My question relates to putting the head back on with the cams in place or putting the cams on after the head is replaced (to avoid damage to the protruding valves).
Gary
Yeah, the same foam is funny. I’d leave the cams off and install them after the head is put back on the block. Did you replace the valve guides?
I just replaced my head gasket and left the cams in place when I removed the head. That’s the way I delivered it to the machine shop and the cams were reinstalled by the shop after they recut the valve seats and set the proper clearances. I had to set the cams to TDC on #1 piston myself.
Remember that the valves themselves are interference, so don’t just start spinning either cam to get
them to the index mark without making sure the intake and exhaust valves don’t collide. You can do it by rotating each cam until there’s about to be interference then move the other cam. A bit of a ballet.
I didn’t worry about bending the valves while I stored it. I simply set the head (valves down) on two wooden blocks, one in the front and one in the back, ensuring that they were clear of the valves.
If you make sure the engine is set to TDC for the #1 piston and the head is likewise set then just drop it on and bolt away. No worries about interference.
A final word, I didn’t worry about rotating the engine while the head was off. That way I could give each piston a good cleaning. I even removed the distributor. Just make sure you line everything up and you’re good to go.
No issues with installation, tdc, timing etc. I just wanted a quick survey on cams on before or after head installation specifically because of the interference setup.
My engine is in great shape after 240k miles. I lapped the valves but in hindsight wished I hadnt touched them. Oil seals even looked new. Probably synthetic its entire life combined with a lot of hwy driving. Next to no wear on the shims.
I would be interested to know how your machine shop set the tappet gaps with the head off the car. You cannot get a true reading that way unless you nut and bolt the 14 head bolts through the head/cam and torque to spec. Suspect that will likely remain a mystery.
What happens to the loose timing chains when you do this?
John …
I had my wife pull the upper timing chain straight up and hold it with some tension while I turned the engine with a socket on the harmonic balancer. This kept it from fouling.
That’s a good woman!
