6.9 head removal

[koan]

The dimensions of the tubular spacer

     ID 12.6 mm (to clear 12mm bolt)

     OD 22 mm

     Height 13 mm

I've uploaded to the gallery here a scan of the manual page and a picture of the spacer. PM me with an email address if the scan is unreadable.

koan

[TJ 450]

Thanks for that info, Koan. I should be able to make something up to that specification.
Also, as I need to retighten the head bolts, is there an extra-long hex key socket available that will clear the exhaust manifold and what about under the camshaft etc?

Tim

[koan]

I should be able to make something up to that specification.

What about a shorter bolt? 13mm spacer minus 3mm washer equals 10mm, a bolt 75mm long wound be just right.

EDIT: That should read 65mm.

Noticed something else today, in the row of five bolts that are at spark plug level (not the row below the exhaust manifold) the hole for the middle bolt has a raised boss about 10 to 15 mm higher than the other four, same on both sides, but all bolts are the same length. 

Also, as I need to retighten the head bolts, is there an extra-long hex key socket available that will clear the exhaust manifold and what about under the camshaft etc?

I used 1/2" drive hex bits and extensions.

Might just be able to do the four bolts under the exhaust manifold with a long square drive 10mm hex bit, mine are short and too fat at the drive end. I recall someone posting in the last few months about a set of long hex bits just purchased.

Or a length of 10mm hex key with a socket on the end.

I doubt there is any possible way of getting at the four bolts under the cam though without removing the cam. Five of the ten bolts that hold the cam supports in place are also head bolts into the block.

A bit of inconsistency in the manual here, it gives a tightening sequence for head bolts that includes the five cam support bolts just mentioned but in the section on removing cam shafts it says to tighten the cam bolts from inside to out which is not the head tightening sequence.

Regarding the need to retighten head bolts, I doubt that it would normally be required but the missing spacer on your engine suggests someone has been in there so it might be worthwhile. An alternate idea would be to leave well enough alone and at some time down the track do heads and valve seats etc.

Thanks for the "It sounds like you are making good progress" encouragement but I fear it's not the case, too many other things on. Today and tomorrow are GST days for the month, I take a break now and then, spend a few minutes cleaning with a tooth brush and carb cleaner and then back to it but there's no hurry. I did much the same jobs as you are doing now a couple of years ago, you are moving at lightening pace compared to me!

koan

[s class]

I doubt there is any possible way of getting at the four bolts under the cam though without removing the cam. Five of the ten bolts that hold the cam supports in place are also head bolts into the block.

I was able to torque these when I retorqued trusty rusty's heads.  I used 3/8" drive as the extensions have thinner shafts.  I used a short hex drive socket, that I inserted into the bolt before attaching the extension to it.  The body of the socket was thus positioned slightly under the cam.  I could then attach the slender long 3/8" drive extensions. 

[s class]

Another comment - some of trusty rusty's bolts were so loose, that I initially went around in sequence torquing them to 50nm, and then went again in sequence for the final torque. 

[koan]

I was able to torque these when I retorqued trusty rusty's heads.  I used 3/8" drive as the extensions have thinner shafts.  I used a short hex drive socket, that I inserted into the bolt before attaching the extension to it.  The body of the socket was thus positioned slightly under the cam.  I could then attach the slender long 3/8" drive extensions. 

I didn't even try to be honest with the cam in place, it looked impossible. My short fat hex bits are far too big, I'll investigate something else like a long bit of 10mm hex key and a socket.

koan

[TJ 450]

I think I'll opt for the shorter bolt. I'll see what I can find. Thanks for that info.

As for the bolts under the camshaft, I haven't yet investigated, but I seem to recall seeing offset inhex sockets. Anyway, the 3/8" drive arrangement sounds like it could be the go, perhaps with a U-Joint as well.

Tim

[s class]

JUst remember that offset sockets, U jounts etc invalidate the indication on your torque wrench. 

[TJ 450]

Thanks Sclass, I'll keep that in mind. I found a suitable 10mm hex key to sacrifice. What I'll do is grind it off just before the bend and use a 6-point socket on it, as you were considering, Koan. Hopefully that will clear the camshaft(s) and exhaust manifold.

Tim

[koan]

Bought a 200 mm long 10 mm hex key today about 180mm of which will be available when the end is chopped off, looks like it will do the job. Waiting on a long 6 mm key for the small bolts around the front of the cam box now. I got them out with an assortment of extensions but was very nervous about losing a bolt or a washer down into the works.

I've just removed the bolt that holds the sprocket to one of the cams, should the sprocket slip off or does it need a puller?

The aim is to discover what sort of keys I have, straight, offset, which way and how much.

koan

[TJ 450]

I managed to remove both sprockets off my M117 without a puller, or any damage for that matter. I seem to recall using a rubber mallet! I would recommend using a puller though, as there is a chance of damage to the woodruff key if it happens to go skew as it is worked off. I then used its bolt and washer to pull it on again.

Tim

[WGB]

I tapped my M117 ones off with a plastic mallet.

Don't remember them being particularly tight.

Yet to do my M100 ones so will be interested to hear how you go.

Bill

[koan]

Couldn't get the sprockets off by percussive methods, I used a puller.  Neither was that tight but as I have the cam and towers off the head, every hit made the cam supports bounce around a bit too much for my liking. Tapping with cam and towers in place may work.

Have to be careful with a puller, select the appropriate size legs to avoid pulling on the teeth rather than solid "rim" of the sprocket, as it was I pulled on bits of timber rather than directly on the sprocket.

I have zero offset keys which makes things easier to go for exact valve timing. If the engineers thought it necessary to make provision for fine adjustment I should do it.

Spent a bit of time on the cam lobe oil tubes, quite a bit of black junk came out while flushing with carb cleaner, will poke out the holes and do more flushing.

Most of the parts are cleaned up now, just throttle linkages and a few other bits. Doing a bit every day has got through the parts pretty quickly. Every thing labeled in plastic bags, about 30 of them.

Just waiting some head bolts from Germany. Not a full set of 36 but a few of mine had some corrosion on the shanks which was a bit more than just surface rust.  At an average price of $9 each they are a bit steep but I'm willing to pay that for the peace of mind that comes with using the "proper" parts in this situation.

On the subject of proper parts still thinking what to do about exhaust gaskets.

koan

[WGB]

Was there much gunk in the oil galleries to the hydraulic lifters?

Bill

[koan]

Was there much gunk in the oil galleries to the hydraulic lifters?

Can't answer that, didn't look. Dismantled heads and took them for valve the grind. They were tanked and are clean now.

Oil does flow through the gallery that feeds the lash adjusters, it's not a dead end. It flows up the rear cam tower, feeds that bearing and there is a drilling into the cam.

I think a lot of the junk in the oil tube was in the closed end.

koan