So I'm half way through the zetec engine rebuild, it's all stripped now and found a couple of odd things along the way:

1) the camshaft sprocket bolt is totally seized...to the extend I started to strip the T55 bolt head (see pic). I know they're on tight but even a 4 foot breaker bar wasn't shifting either bolt. I don't want to get the blowtorch on out cos it'll likely distort the sprocket or camshaft. Anyone else had this problem?
I'm just going to leave the sprocket attached and will have to reuse the oil seal.





2) one of the oil gallery grub nuts is missing! Got to the end of the stripdown and thought I'd lost it somewhere but looked back through old photos and nope, it's never been there! Not really an issue they're easily replaced, and the engine was dirt cheap when I bought it. Just weird random piece to be missing.
Good job I wasn't ever going to run it before rebuilding otherwise oil would be everywhere

Spot the missing grub nut:

Ok so not very familiar with these engines but the missing grub nut, is that not just where the oil pressure switch goes?

As for the cam bolt, it's not a left hand thread is it? Have you checked the bolt part number for both cams is the same? I think I'd check just incase some crazy engineer thought it was a good idea.

If not you could try welding on a 1/2 drive socket, say a 18mm onto the face of the bolt, TIG would be ideal, hell you've trashed the bolt anyway and the heat should help free it.






[Edited on 8/11/20 by Mr Whippy]

Big Wasa is the expert on the Zetec, but with regards the pulley bolts I think they are Loctited in place
I'd use a hot air gun just on the bolt and then use a windy gun if you have one or a breaker bar to loosen the bolt

The hot air gun and then the windy gun has helped me several times with the crank pulley bolt on a Vauxhall XE and that's bleedin tight

as well as the hot air and windy gun - have you soaked it in plus-gas? Not WD40 but a proper penetrating fluid?

(nb if it is loktite'd id not expect the penetrating fluid to make much difference)

Have you tried an impact wrench, that helped remove mine.

Those cam bolts can be tight to crack off. We've broken a few torque bits on them and bring quite shallow makes it worst. We've also seen the timing tool slot at the other end damaged where that's been used to lock it previously rather than a proper cam holder used.

The "missing grub screw" is actually where the oil pressure sensor has been removed.

Aaah...yes, you're both right! I've googled some images and it's the oil pressure sensor hole. OK so, I've got a missing oil pressure sensor not a missing grub nut (checked the loom it's not there). Will add to the list of parts i need to buy

Sprocket nut has had windy gun, extender bar, extension on the extender bar, and impact wrench...all the tools in my garage have been thrown at it.
But tbh i think i'm going to leave it as-is now and reuse the oil seals.

Checking the tolerances (piston rings, end-float, etc) they're all v.close to minimum, making me think this is a pretty tight engine (I don't know the milage on it) I don't think re-using will be a problem and there's no other reason to take the sprocket off really? (keeping it on will help with timing too)

I would clamp the sprocket in a decent vice, if it gets damaged there are plenty around , then use a chisel against the head of the bolt and give it a few clouts with a hammer to turn it anti-clockwise. A new bolt which it needs anyhow and jobs a good one . As mentioned use a proper tool when tightening the cam bolts not the timing tool

You may not need the switch depending on your gauges. Some are a combined oil pressure sensor + low pressure warning switch.

Knowing the cam pulley bolt is messed up is just saving the problem for later. I would sort it now while you have good access.

Edit, besides. If someone has timed it with an old belt it could be out.

[Edited on 9/11/20 by big_wasa]

Weld a nut onto it. The heat will loosen it off. A guy over on the wscc forum had the same issue.

Cheers guys....looks like applying some heat is the next step then