Camshafts

[silbeer]

Does any one know the specs for the cams from the GK76SP?

I have the manual with the SP supplement but doesn't give any specs for the cams.

Just for reference the non-SP specs as follows

Intake opening BTDC 46
Intake closing ABDC 66
Exhaust opening BBDC 64
Exhaust closing ATDC 24
Intake centerline 100
Exhaust centerline 110
Intake Duration 292
Exhaust Duration 268
Overlap 70

Any one feel like degreeing their SP cams?

[dobbslc]

Hi silbeer can you give me any info on cam positions etc for when I take the head off my engine? ie which pointer faces what.
I also need head bolt & cam cap torque settings and any other useful tech bits.
Thanks.
Dobbs

[Variablevalves suck]

Hi Dodds,
head bolts are torqued at 25/29 N.m and in the order of the numbers cast in the head. Cam journal holders are 8/12 N.m. I cannot remember the cam alignment unless looking at them so take the LH casing off turn the motor till the 'T' is alined with the small arrow by the upper/lower casing split and get a few pictures of the cams befroe you take em out.

@ Silbeer as far as i know the SP's have the same cam as standard on the exhaust but a revised inlet cam.

[dobbslc]

Top man VVS!
If you have any more info like that it would be appreciated.
Now I just need to take it apart and see what caused all the smoke! , are the head gaskets / rings commonly known to fail on these engines?
Dobbs

[Variablevalves suck]

Sounds like the head gasket, if you need any more info just ask.

[dobbslc]

Yeah there's some mayo in the exhaust & oil running down the front of the barrels. Hopefully that's why I've only got about 100psi of compression on the cylinders.

[dobbslc]

I've just got the head off & have just checked a few of the rings and found the top rings measure 0.35-0.40mm end gap at the top of the cylinder and the others 5.8-6.1mm free so I think there all ok.
How would a blown head gasket let oil into the cylinders when there should be no oil up there in the first place?
Is there any chance the valve stem oil seals have gone?

[Variablevalves suck]

Hi mate,
Piston ring free end gap is 4.5mm 1st, 4.6mm 2nd. Service limit
Ring end gap fitted is 0.5mm 1st and 2nd. Service limit.
Could well be seals and worth doing while in there. You can usually tell if any are leaking by the mank around the valve exit. Check ya water for oil and oil for water.

[dobbslc]

Yeah I've got a lot of crap on the no 1 cylinder valves (looking up the exhaust port,) Will have to check the cost of valve seals
VVS do you think the rings are within spec? Just to be sure I'm reading it right. ie rings measured installed in cylinder = 0.35mm & if 0.50mm is the max allowed this is ok yes?

[Variablevalves suck]

Hi mate,
Seals are pritty cheap, do you need the part no. ? makesure you get the correct ones as 76a and 73a are not the same. Yes its 0.5mm max gap fitted.