Isuzu G-series Twin Cam

Hey all,

I know this is a really stupid question, but having snapped a cam clean in half last time I tried, I'd rather ask it than wing it.

Right now, my twincam is in the shed with the sump, timing case, and head on, at TDC. The inlet cam has been fitted, and the exhaust cam itself is fitted however the front cog is not on. The timing chain does not have enough slack to allow me to put the cog on, so I need to disengage the chain tensioner(s), put the cog on, rotate the cam to the right spot, put the chain on then re-tension the timing chain.

How on earth do I do this? On the G***Z engines it's easy enough, you can see the tensioner in the timing case, looking through the head. But I can't see anything of the sort, I know more or less where the tensioner(s) are, having fitted them with the timing case, but that was ages ago, and I don't know how to get to them.

Also, what should I be torquing the cam bearings up to? At the moment they're just nipped, but given the rareness of cam bearings I'd rather a torque spec.

Eli

Sure if Im wrong I will soon be corrected...

Tensioner is slackened off by removing the socket head cap screw (allen key) on top of the timing case,under the dizzy....once thats out youll need a tiny flatblade screwdriver to fit in the threaded hole and lever the tag back.

With the cam bearing caps...I just set them to SOHC specs.

Good Luck!

Todd

Thanks a lot man, I was worried noone would reply and I'd be screwed! Haha... I'll give it a whirl and see how I go Happy new year.

Just looking now at the G180W and it doesnt have that allen key bolt I mentioned...I was thinking of the G200W

Someone will come along and explain it....Elky!? haha

i would explain it but believe it or not i have not done a timing chain / tensioner refit yet!

might do soon on the zz/t as the welsh plugs on the head are gettin corroded

cheers

Wow! lol, I'm screwed now Maybe Poida will know.

Next time I'm out there I might pull off the bottom cog cover and see if that helps at all. Or perhaps jamming foreign objects down the timing case, like screwdrivers... No, actually, that doesn't sound like a good idea

Have you tried taking that big headed bolt on the drivers side off...its the one that sits on the side of the timing cover,where the metal oil feed line runs up from the oil filter housing....

Id start there maybe....good luck LOL

Todd

Can you remove the inlet cog and fit both simultaneously? (Otherwise the crank cog also.)
I think my OHVs needed this approach, though they have a much shorter cam chain.