# Do these valves look like they're burned?



## ownerof2011cruze (Sep 8, 2018)

What should be done to inspect these valves from my head to determine if the head should be replaced? This is from my 2011 LT with LUJ VIN 8th digit code 9 with 110K miles which extremely overheated last year. (It was all my fault because when I changed the temp sensor in the radiator I failed to get the new sensor properly seated and secured and it popped out on the freeway in heavy rush hour traffic on a hot day. )


----------



## snowwy66 (Nov 5, 2017)

A machine shop would tell you more then anyone on the forum with eyes.

Your head looks standard to us.


----------



## jblackburn (Apr 14, 2012)

If it overheated and popped a head gasket, there is a 100% chance it warped and you'll need to take the head to a machine shop to resurface it or buy a rebuilt one anyway. They'll want to plop it in a parts washer and check for any small cracks in the head before doing any work to it.

It looks like the head gasket breached in that right cylinder and steam-cleaned the valves a little bit, but they all look ok.


----------



## DWSCruze2012 (Feb 18, 2013)

+1 to both the above.
Personally, I cannot IMAGINE me taking things apart THAT FAR then not getting the heads to a shop.
I mean there is such a thing as being penny wise and pound foolish.

If you (like me, at times in my life) FLAT OUT DON'T HAVE THE MONEY then, well, all you can do is put it back together and hope.

Like snowwy66 says: If you have enough money.... Take it to a shop. If they put it in the parts washer they can also tell you how warped it is/isn't. 

110K miles. rings/bearings all probably OK so... why not have head and valves in great shape?


----------



## ownerof2011cruze (Sep 8, 2018)

DWSCruze2012 said:


> +1 to both the above.
> Personally, I cannot IMAGINE me taking things apart THAT FAR then not getting the heads to a shop.
> I mean there is such a thing as being penny wise and pound foolish.
> 
> ...


Hey there.Thanks for the comment. Good point Yes. My Cruze is a project car and not the daily driver. I have 2020 Trax for work. I hope to be able to do these various tasks myself, but it is a good idea to have a shop wash it and test it. First I intend to find out if it's warped thus providing a good reason to buy a new tool.









24" Bevel Edge Straight Edges with Scale at Grizzly.com


These 24" Bevel Straight Edges are made from hardened steel and feature a satin chrome finish and are ground and lapped for straightness and parallelism.<p><li>True right angles for all edges<li>Bevel edge with scale<li>US standard<li>Accuracy: 0.001"<li>Resolution: 1/64"</ul>




www.grizzly.com





And BTW, which of these valve spring compressor tools would work on the LUJ/LUV head?



Amazon.com : valve spring compressor tool


----------



## jblackburn (Apr 14, 2012)

I believe @JLL has done some head work on these motors.


----------



## ownerof2011cruze (Sep 8, 2018)

ownerof2011cruze said:


> Hey there.Thanks for the comment. Good point Yes. My Cruze is a project car and not the daily driver. I have 2020 Trax for work. I hope to be able to do these various tasks myself, but it is a good idea to have a shop wash it and test it. First I intend to find out if it's warped thus providing a good reason to buy a new tool.
> 
> 
> 
> ...


And is it more common to find head casting 55573669 or 55565291 on the 2011 2012 LUJ code engines?


----------



## ownerof2011cruze (Sep 8, 2018)

jblackburn said:


> I believe @JLL has done some head work on these motors.


Thanks for the reply. Yes JLL is a smart guy and seems to be a pretty good mechanic. I admire his work.

And I did finally manage to measure the conn rod bearing journals this morning and found them to be within specified dimensions, so I then ordered the standard size Enginetech BB140J bearings and the GM 25198520 pistons. I'm making a little progress on this.

Or is this one commonly found on PL69(LUJ) engines?






55573010 - GM Parts Giant







www.gmpartsgiant.com


----------



## snowwy66 (Nov 5, 2017)

When I replace bearings. I go .005 over. Maybe higher.

Whatever that measurement is.

Tighter clearances provide higher oil pressure. 
And you said there's 110k on the crankshaft.

Oversized bearing can make up for the crank wear and tear.


----------



## JLL (Sep 12, 2017)

ownerof2011cruze said:


> And is it more common to find head casting 55573669 or 55565291 on the 2011 2012 LUJ code engines?


As far as I know the casting are identical. I believe the earlier heads were 669 and the later heads were 291. My car came with a 291 and I replaced it with a 669.



ownerof2011cruze said:


> Thanks for the reply. Yes JLL is a smart guy and seems to be a pretty good mechanic. I admire his work.
> 
> And I did finally manage to measure the conn rod bearing journals this morning and found them to be within specified dimensions, so I then ordered the standard size Enginetech BB140J bearings and the GM 25198520 pistons. I'm making a little progress on this.
> 
> ...


Thanks for the compliment. The pistons have been revised over the years. I recommend ordering the most recent part number when installing OEM replacement pistons.

As for the valves they don't look burnt, just dirty The black valves are the intake valve and they are black brand new from GM. The gray looking valves are the exhaust valves and those are more bright silver when new from GM.


----------



## ownerof2011cruze (Sep 8, 2018)

According to GM 55573011 Head, genuine OEM part Chevy replace my CH's part no. 55565291 with 55573011

*55585290* was replaced with *55573011* on August 1, 2012 for the U.S. market;
*55565295* was replaced with *55573011* on June 1, 2012 for the U.S. market;
*55573010* is interchangeable with *55573011* since September 1, 2011 for the U.S. market;
*55573010* is interchangeable with *55573011* since July 1, 2011 for the U.S. market.
My local engine rebuilder machine shop quoted me $225 plus parts. A full set valves, springs, guides, seals, keepers and so forth runs about $800. My 55565291 head overheated so I would think it's warped. Gonna check with my Chevy dealer parts guys to see if 5557310 or 55573011 is available for a reasonable price.

Or the DIY cool way:


----------



## ownerof2011cruze (Sep 8, 2018)

Carid's online inventory was wrong. They don't have conn rod bearings in stock. Cancelled order. Will buy from Chevy dealer parts department.


----------



## ownerof2011cruze (Sep 8, 2018)

ownerof2011cruze said:


> Carid's online inventory was wrong. They don't have conn rod bearings in stock. Cancelled order. Will buy from Chevy dealer parts department.


Bought conn rod bearings & bolts from chevy dealer parts dept much le$$ than Rock or Carid.

55568531 bearings $5.35 /set vs ~$22 /set on R or C
55562190 CR strap bolt $4.42 vs ~$339 /set of 8 bolts on C (that must be a decimal slip.)

Took cylinder head to machine shop for cleaning, pressure & vacuum tests and to be milled flat if warped. May need a shim for install.


----------



## ownerof2011cruze (Sep 8, 2018)

Pistons delivered today. Unboxing 25198520.


----------



## snowwy66 (Nov 5, 2017)

I'm surprised pistons even last these days. 

Talk about slimming down.


----------



## forumlove99 (6 mo ago)

Yes mine as been long and still active 


Sent from my iPhone using Tapatalk


----------



## ownerof2011cruze (Sep 8, 2018)

ownerof2011cruze said:


> Bought conn rod bearings & bolts from chevy dealer parts dept much le$$ than Rock or Carid.
> 
> 55568531 bearings $5.35 /set vs ~$22 /set on R or C
> 55562190 CR strap bolt $4.42 vs ~$339 /set of 8 bolts on C (that must be a decimal slip.)
> ...


Picked up CH from machine shop. Nice and clean now, it passed pressure and vacuum tests. They milled it flat. Will order .02" thick spacer for install, but somehow their worker damaged an exhaust valve rocker for cylinder 4. Will take it back to see if they'll fix it.


----------



## ownerof2011cruze (Sep 8, 2018)

pics of askew rocker: how can this be fixed?


----------



## ownerof2011cruze (Sep 8, 2018)

What's the right way to lube or oil up the valve lifters? Should the head's oil gallery be filled just prior to install onto the block?


----------



## ownerof2011cruze (Sep 8, 2018)

ownerof2011cruze said:


> What's the right way to lube or oil up the valve lifters? Should the head's oil gallery be filled just prior to install onto the block?


Will get quotes from local chevy dealers for 16 each lifter 09128603 & rocker arms 09129211. While head is off might as well replace old parts.


----------



## ownerof2011cruze (Sep 8, 2018)

Machine shop milled off 36 thousandths from cylinder head sealing surface. Since it's an interference fit engine, I figure it now needs to have the DNJ shim installed on the block prior to placing the head to prevent valve and piston damage. The shim has to be sealed to the block so it will not slide around while shifting the head to get it into the right position. What can be used to seal the shim to the block which will not make matters worse and actually work to keep compression and hold coolant?


----------



## JLL (Sep 12, 2017)

ownerof2011cruze said:


> pics of askew rocker: how can this be fixed?
> View attachment 298589
> 
> 
> View attachment 298590


Pull the cam out and reorient the rocker.


----------



## JLL (Sep 12, 2017)

ownerof2011cruze said:


> What's the right way to lube or oil up the valve lifters? Should the head's oil gallery be filled just prior to install onto the block?


I like using an assembly lube spray.


----------



## JLL (Sep 12, 2017)

ownerof2011cruze said:


> Machine shop milled off 36 thousandths from cylinder head sealing surface. Since it's an interference fit engine, I figure it now needs to have the DNJ shim installed on the block prior to placing the head to prevent valve and piston damage. The shim has to be sealed to the block so it will not slide around while shifting the head to get it into the right position. What can be used to seal the shim to the block which will not make matters worse and actually work to keep compression and hold coolant?


The LUJ was not designed to use shims. The head really should have been replaced entirely.
But since the head has already been machined you could try to salvage things by machining the correct passages in the shim, coverting to head studs, and putting a head gasket on each side of the shim.

BTW, the LUJ is NOT an interference engine under normal circumstances. With 0.036" machined off the head it now could be though.


----------



## ownerof2011cruze (Sep 8, 2018)

JLL said:


> The LUJ was not designed to use shims. The head really should have been replaced entirely.
> But since the head has already been machined you could try to salvage things by machining the correct passages in the shim, coverting to head studs, and putting a head gasket on each side of the shim.
> 
> BTW, the LUJ is NOT an interference engine under normal circumstances. With 0.036" machined off the head it now could be though.


Thank you. Good advice. My engine rebuilder machine shop guy clued me. His mill operator took less than .01" off the sealing surface. The 036 number was for the ticket. I was wrong to think that was the number of thousandths taken off. I've been wrong about a lot of stuff in my life. When I look back on some of my misadventures I have to laugh at my foolish folleys. So to compensate for the material taken off the sealing surface of the cylinder head, I'm going to use the Mahle 54898 head gasket that lists as being .03" thick as opposed to the GM 55562233 that lists as .022" thick. The extra 8 thousandths might be enough space that the pistons don't crash into the valves at top of exhaust stroke/start of intake stoke.










Cylinder head needs needs lifters, rockers, springs. Should have shelled out the cash for new manufacture head, but working on vehicles is fun, so it's money well spent.Pic of mill job on sealing surface. Very flat. No light from flashlight visible under 24-inch long .001" straight edge laid on surface. Mill operator honed intake valves.

Cleaned block deck and measured for flatness. Was able to get .003" feeler gauge under 24-inch straight edge between cylinders 2 & 3. Thinking block should be milled and magnafluxed. Conn rod journals measure at low side of diameter range." Bearing clearance will be .0026" to .0048. The right thing is to install a new crank or to have current crank journals ground and polished to diameter suitable for undersize bearings.

Chain puller 1 Ton Manual Chain Hoist


----------



## ownerof2011cruze (Sep 8, 2018)

Connection rod standard bearing clearance will be .003" to .0045". This is over max spec clearance. If installed as is, how long before self-destruct?









#1


----------



## JLL (Sep 12, 2017)

ownerof2011cruze said:


> Connection rod standard bearing clearance will be .003" to .0045". This is over max spec clearance. If installed as is, how long before self-destruct?
> View attachment 298634
> 
> 
> ...


275 Days, 14 Hours, 32 Minutes, and 17 Seconds!  

Seriously though, If you deglaze the cylinder walls when they're out of spec and assemble the engine, the rings may not seat properly, if at all. If that happens, you'll have low compression burn a good amount of oil.


----------

