Fox T-Bird/Cougar Forums

Technical => Engine Tech => Topic started by: croga001 on February 27, 2010, 10:41:29 AM

Title: 2.3 rebuild questions
Post by: croga001 on February 27, 2010, 10:41:29 AM
i pulled the head off of the motor thats going in my dads car and sent it out to get worked over (valve job and roller cam) now that i can see the pistons i think i have a problem.  the piston comes out over the top of the surface a little bit and there was a considerably thick copper head gasket on it.  The cyl also look like they are honed already.  do they still make head gaskets for motors that have been machined?  Do you think i should just get a new shortblock and start over?
ideas please guys, i dont want to run into problems when i get it back together.
Title: 2.3 rebuild questions
Post by: fordguy545 on February 27, 2010, 12:48:08 PM
??  The pistons shouldnt be taller than the deck!  Are they stock pistons? or oversize?  They do make mls headgaskets.  Dont remember who makes them, but they can make pretty much any thickness.  Do a search at turboford, and you will probably find what you are looking for.
Title: 2.3 rebuild questions
Post by: Chuck W on February 27, 2010, 02:05:19 PM
As far as I recall, on a 2.3T the pistons do come up past the deck (but not the HG).  I don't remember the exact dimension though.

Obviously though, if the engine was running, or could be turned by hand, the pistons were not contacting the head.
Title: 2.3 rebuild questions
Post by: fordguy545 on February 27, 2010, 09:11:16 PM
none of my turbo pistons are above the deck.  Even on the engine I had decked(that ones pretty much even)
Title: 2.3 rebuild questions
Post by: jcassity on February 27, 2010, 09:21:48 PM
sounds like someone may have themselves a little stroker and doesnt know it.
Title: 2.3 rebuild questions
Post by: bigbada1 on February 27, 2010, 10:10:42 PM
Are there valve releafs cut into the pistons???
Title: 2.3 rebuild questions
Post by: croga001 on February 27, 2010, 11:14:54 PM
the pistons do have a recessed area to them.  im assuming the pistons are stock.  they come up above the deck eough for the eye to see it.  the engine was running and quite well actually.  i just wanted to go over it and put new gaskets in it before putting it in my dads car.  pretty sure its the stock crank and everything too.
Title: 2.3 rebuild questions
Post by: jcassity on February 28, 2010, 01:08:33 AM
theres a reason why the high quality copper gasket was on there.

the block was decked and the head was milled.  adding the headgasket shim back on fixed everything.

you should clay the top of the pistons then snug the head down without a headgasket and tell us if valves break through the clay and hit the piston or not.

you could also use play dough.
Title: 2.3 rebuild questions
Post by: Chuck W on February 28, 2010, 07:32:40 AM
Yeah, I did some digging, and the factory spec on the piston deck height is .017" stock.

So yeah, they should be down in the block.  You need to measure how much they are sticking up past the deck.

Sounds like someone REALLY decked that block.

Why don't you take some pics of what you have?
Title: 2.3 rebuild questions
Post by: jcassity on February 28, 2010, 11:22:27 AM
that little thing must have some good compression.

dont go short on new headgasets, use that old copper one or one like it the same thickness.
Title: 2.3 rebuild questions
Post by: bigbada1 on February 28, 2010, 11:46:39 AM
I would use a cometic copper head gasket
Title: 2.3 rebuild questions
Post by: TurboCoupe50 on February 28, 2010, 11:49:01 AM
Unless they are more than .010-.015 out of the hole I would not worry about it, especially if it was running OK prior... Most head gaskets are around .040 compressed, so you still have piston to head clearance...

Pistons on my ole 5.0 were maybe .003-.004 out of the holes and it'd never been decked...
Title: 2.3 rebuild questions
Post by: croga001 on March 01, 2010, 02:20:21 AM
ill try and snap some pics next time im up there.  idk if i want to resuse the old gasket ill get a new one.  the guy who is doing the head seems like a guru so ill ask him what i should do about the gasket.  he should have the head done with the new cam now so ill have to run up there soon to see him.  while im up there ill stop at my dads too.  is there a way to check if the rings are sealing good without the head on the car?  i wanted to do a compression check before i took the head off but then i thought that if the gasket was leaking a little that it could through off the results so i waited.
Title: 2.3 rebuild questions
Post by: BogusSVO on March 01, 2010, 12:41:13 PM
yes the pistions should be in the block about .015.

Turbo 2.3 pistons have a D shaped dish in the about .095 deep

stock compresion on a turbo engine is 8:1.. if the engine has been gone thu, the block and/or head may have been milled to raise compression

compressed thicknes of the 1035 is .041 thick
Title: 2.3 rebuild questions
Post by: croga001 on March 01, 2010, 02:26:55 PM
ok sounds good im going to measure the thickness of the old gasket and see what we decide to do.  i do have stock turbo pistons though i know that now.
Title: 2.3 rebuild questions
Post by: croga001 on March 05, 2010, 12:51:16 AM
well bob still has my head and will not answer his phone.  we took a drive up and he was not there so idk i guess we will wait to hear from him.  tax returns came in and it was 40 this week so im really getting the itch to start working.