Special tool 18G 694 - head spanner

[BMC problems]

Does anyone have this tool, or a fabricated alternative that i could borrow so I can torque down the head in the proscribed sequence?

 

It's impossible to tighten down as per the manual without it as 3 are hidden by the rocker shaft.

 

The alternative is to torque down the ones without the rockers in place followed by the 4 rocker shaft ones.

 

As a bodge, am I asking for trouble doing this?

[BMC problems]

Another question....

 

On one of the rocker pillars, above the oil way is a screw held in place by a special washer on one of the smaller rocker shaft studs.

 

What is this? And should it be adjusted ?

[RLWP]

You don't need the special tool. Machine Mart sell a set of crows foot spanners to go onto a 3/8" drive. Using a 3/8" extension you can clear the rocker shaft and use a torque wrench

 

I think that screw is the one that holds the rocked shaft in the pillar. All the other pillars are free to slide along the shaft

 

Richard

[dor]

Can't you just remove the rocker shaft? I did this on my Vetus Mitsubishi which has similarly placed head bolts.

[RLWP]

The risk is that one of the pillars moves while torquing the head down and you can't slip the shaft back through

 

Richard

[Tony Brooks]

The risk is that one of the pillars moves while torquing the head down and you can't slip the shaft back through

 

Richard

 

But aren't the 1.8 posts held down by two studs like the 1.5, the head stud and 5/16 one that only secures the post. I think that if you fitted the rocker gear as a complete assembly and tightened the 5/16 studs they would hold the posts tight enough so they do not move. Then strip the shaft out (best not do it this way unless you like jigsaw puzzles -loads of washers and springs etc.) and tighten the head nuts. finally reassemble the shaft.

 

However I agree the clearance on the head stud holes might allow one to move and the reassembly will not be straight forward so I think the crows foot is the best way to go.

[RLWP]

 

But aren't the 1.8 posts held down by two studs like the 1.5, the head stud and 5/16 one that only secures the post. I think that if you fitted the rocker gear as a complete assembly and tightened the 5/16 studs they would hold the posts tight enough so they do not move.

 

And how frustrating will it be when one pillar moves a fraction?

 

Richard

 

MORE: This is the set I bought: http://www.machinemart.co.uk/shop/product/details/clarke-crows-foot-imperial-wrench-set-8-piece?da=1&TC=SRC-crow%20foot

Edited June 15, 2014 by RLWP

[BMC problems]

Thanks all. I am (enormously) reluctant to dismantle rocker shaft and to have to loosen in after....

 

I'm also ( slightly less) reluctant to buy £20 of tools that I will almost never use and just make my toolbox heavier. (And a 1/2" 3/8" adaptor)

 

One last question; torquing the first 10 then fitting the rocker shaft? Probably OK, bit risky or total no-no?

 

 

Size is 11/16" crows foot?

Edited June 15, 2014 by BMC problems

[RLWP]

£20 of tools, or do the job twice. That's not an easy choice

 

Richard

[BMC problems]

Total no-no then? It won't torque down properly like that?

 

Please bear in mind I'm not an engineer

[RLWP]

To be honest, there are lots of BMC 1.5 engines out there, not so many crows foot spanners and fewer still special tools. So there will be a lot of heads fitted 'wrong' that work fine. And some that don't

 

So, if you do the job properly - new gasket, scrupulous cleaning of the head and block - it will probably work OK without using the right tools. And it might not - and the consequence might be water leaking into the cylinder and a bent rod

 

Lots of mights in that statement

 

Richard