Doing the tensioner replacement, on the right side, everything smooth, the damn cam doesn't just "lift out". It seems quiet stuck in fact.

I have read through many threads on this, and I don't recall anyone having an issue lifting the cam. Any idea why mine seems stuck? The lifters would want to push it out it would seem, and I have given some serious tugs on it. Haven't resorted to a pry bar (yet) as I have time for sage advice. Arghh!!

Thanks!

 

Mike, were do you think it's stuck? The only place I think it could get caught up is at the sprocket end, you might need to put a couple of caps back on towards the back to level the cam. I think you've tilted the cam up at the back locking it.

 

The tensioners push in different directions on each side. Is this the side where the tensioner is pushing down on the bottom run of the chain? In that case slack off the tensioner bolts a bit. If the cam moves a bit, then that's the one. You would then want to slacken/remove the tensioner bolts/tensioner to let the cam come up. Without dropping anything into the black hole. Weaseling because I don't know which side means right/left since no point of view reference was given.

If that isn't it ... then:

Surface tension of the oil at the cam journals? How about light taps with a *small* hammer at the ends along the axis of the cam? Or rocking it a bit?

No pry bars! Believe it or not the camshaft is hollow with lobes that have been pressed in.

 

See this posting as a warning of how fragile the camshafts actually are...
https://www.jaguarforums.com/forum/j...84/#post305170

Loosen the tensioner bolts and try to get some slack in the upper timing chain when compressing the tensioners by hand.
Now as you pull on the camshaft evenly, try to turn it slightly in one and the other direction. My guess is that it just seems to be stuck because the thin oil film between the cam and it's "seats" kind of sucks it stuck.

Good luck and be careful!


David

 

Thanks for the advice, guys. Mirrors what I have been dreaming over the night. I think I will try Sean's advice first, as the cam is definitely at an angle in there, being pulled towards the center at the cam gear, biasing it out in the rear (barely, but perceivable). Then, with the journals on, but loose, I will try to wiggle the heck out of the thing to see if it will loosen within that more controlled parameter.

I noted the hollow nature of the thing, surprising. Makes sense from an engineering perspective if you want to more fully optimize.

I will get that sucker after church. No prying!

I will let you know how it turns out...

 

This is NOT good!
Did you turn the engine (by hand using a 24mm socket & wrench) to a position where the cam lobes pushing the valves in as little as possible?
I did it that way and had no problems removing (and reinstalling) the cams.

Regarding my comment of compressing the old tensioners - If you loosen the 2 bolts that are holding them and then compress the tensioners by hand you'll get the oil (that dampens them) out. So it will get more easy to produce some slack in the upper timing chain. That in the end helps to slightly turn the exhaust cam back and forth while loosening the cam caps. This way it is fairly easy to lift the cam evenly off it's seats while unbolting the cam caps.

Good Luck!

David

 

The cam came unstuck. Sean's idea to level it with reapplying rear caps did the trick - just eased out. The other side was uneventful, though the entire job took longer than others, about 6 hours. I did change my plugs and flush the coolant, and adjust the throttle, so the time included this too. No oil leaks yet, though I found the amount of torque called for rather light.

The tensioners were bad. They were both cracked in the telltale way I have seen on many pics here on this forum. I am confident they were leaking oil at least, and continued to degrade. Good call to catch that and nip it in the bud. Thanks to the people here on this forum, past and present!! I saved who knows how much grief, and gotten great ideas for my cat!

Post cat idles and runs like a top, smooth as glass, and definitely more responsive. Impossible to parse out why with so many changes, but suffice it to say I like the end result. Unfortunately, it is raining here at the moment, so I could not get on it yet in earnest, but the bit of romping I did showed promise.

Now, if in the morning the startup does not have the ticking that got me concerned in the first place I will be truly blessed! And no oil leaks either.

Thanks again for the help and advice, gents!

 

No, just praying.

You left yourself wide open

 

Nice to know it's up and running well!

 

No ticking noise on morning start. Not definitive, but promising. No oil leaks. Yea!!