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General Information => Troubleshooting => Topic started by: ienjoysnails on July 03, 2011, 06:37:48 pm

Title: valve/piston clearance issue
Post by: ienjoysnails on July 03, 2011, 06:37:48 pm

erase

Title: Re: valve/piston clearance issue
Post by: dieselweasel on July 05, 2011, 04:56:55 pm

Did the machine shop do any work to the head besides remove stuck injectors?  Did they mill the surface?  I'm concerned about the different valve opening distances...perhaps they made an error re-assembling the head?  I'd be inclined to remove the valves and check everything...

Title: Re: valve/piston clearance issue
Post by: ienjoysnails on July 05, 2011, 07:06:55 pm

the head was only off to facilitate easier removal of the stuck injectors.  nothing was done to the head itself while at the machine shop beside being manhandled

Title: Re: valve/piston clearance issue
Post by: theman53 on July 05, 2011, 07:36:20 pm

I would guess that your timing mark is off????

Or the shop bent your valves getting the injectors out.

Title: Re: valve/piston clearance issue
Post by: rabbitman on July 05, 2011, 08:14:46 pm

Quote from: theman53 on July 05, 2011, 07:36:20 pm

I would guess that your timing mark is off????

Or the shop bent your valves getting the injectors out.

Good call, probably thumped it down on the work bench and a valve landed on a socket or something.

Title: Re: valve/piston clearance issue
Post by: vanagonturbo on July 05, 2011, 08:33:58 pm

'locked the crank'

How exactly do you lock the crank in place on a 1Z? FWIW, NEVER put the crank at TDC when installing a head with cam installed. I always put the pistons in the middle of their stroke when I put a head on. Marks can lie to you..

Is it bad that I looked at your location when you said you had to take the head to a machine shop to get the injectors removed?

West coaster here..

Title: Re: valve/piston clearance issue
Post by: ienjoysnails on July 06, 2011, 05:56:20 am

i "locked" crank using a strap wrench and locking plier.  very backyard mechanic but it works.  i'll make sure not to install head again while at tdc

when the head is off i'm able to verify tdc by looking at the pistons in their stroke, and it perfectly matches up with the marking on flywheel, so thats good.

what might cause a valve to open excessively far?  seems like some of them open a tiny bit and some open alot.

Title: Re: valve/piston clearance issue
Post by: theman53 on July 06, 2011, 07:02:53 am

PICS

Cam lobes could be messed up or bent valves not letting it come all the way up. I would try to rotate the camshaft with the head off the car and see what you get.

Title: Re: valve/piston clearance issue
Post by: ienjoysnails on July 13, 2011, 11:07:51 am

erase

Title: Re: valve/piston clearance issue
Post by: rallydiesel on July 13, 2011, 12:41:43 pm

Looks like the oil leaked out of the followers causing different valve lifts. It will go back to normal after a few cranks.