[d.wamsley]

Hi, I'm working on my first sierra (88 wt) and have had my block decked (g13a). Was installing the new pistons yesterday and my piston top is sitting slightly above the deck now. It's prob out about 1/10th of a mm. It just feels like a little lip. Has anyone had this before with these engines. Do you think the head gasket will give me the clearance or should I get the pistons machined the same amount the block has been. I'm planning to call the shop that did the work Tuesday for advice but thought it won't hurt to start here.

Thanks
Darren

[JrZook]

Sounds like you will have to determine that yourself by using pieces of solder appropriately placed on the piston crown and turning the engine over by hand with the headgasket and head tensioned to spec. If it does not interfere with the head you will be able to measure your clearance by measuring the squished solder thickness.

[31zook]

My G13A high compression pistons stuck out the top of the block, no contact.

[want33s]

JrZook wrote:

Sounds like you will have to determine that yourself by using pieces of solder appropriately placed on the piston crown and turning the engine over by hand with the headgasket and head tensioned to spec. If it does not interfere with the head you will be able to measure your clearance by measuring the squished solder thickness.

Solder??? I've only ever used soft stuff plasticine or blutac.

[Trypt]

solder will hold its shape much better after being compressed
then you can mic the solder to check ur clearance.

[sideways]

x3 on solder.

Check every cylinder too, they vary a bit.

[d.wamsley]

Thanks for the tip. I will give solder a go.

[JrZook]

want33s wrote:

JrZook wrote:

Sounds like you will have to determine that yourself by using pieces of solder appropriately placed on the piston crown and turning the engine over by hand with the headgasket and head tensioned to spec. If it does not interfere with the head you will be able to measure your clearance by measuring the squished solder thickness.

Solder??? I've only ever used soft stuff plasticine or blutac.

Yep! And the solder I mean is just electronic grade rosin core stuff (not the hard plumber stuff!). Would be very hard to accurately measure compressed blu-tac and other really soft stuff.

[want33s]

Fair enough........ The blutac isn't for taking measurements it is just for checking clearances.

[d.wamsley]

Measured up, and the pistons are getting skimmed 15 thou to make sure everything is cool. Thanks for the advice and help.