swathdiver
Full Access Member
Awesome, thanks!
Head gasket replacement checklist
- Thread starter Matahoe
- Start date
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Awesome, thanks!
OP
OP
Yes but what could the difference be? The only thing I can think of is the addition of AFM/DOD in 2009 and above engine. They should both fit. The later valve cover is half the price! I am tempted to buy both from the dealer and compare.
swathdiver
Full Access Member
I think the difference lies in the size of the hose fitting coming out of the valve cover.
OP
OP
Got done cleaning all the valves and rebuilding the lifters. The washed out area on the passenger head that looked suspicious seems to be a crack. I used a two part red penetrant and developer. I had to edit/highlight the crack because I sprayed too much developer and it covered it up.
This is all preliminary checking and I still want to pressure wash the head today and redo the developer test. Still wondering if it is worth having a machine shop do their own tests regardless of what i find? At this point I am tempted to just slap on a head gasket, button everything back up and live with it. Although re-torquing the head may result in elongating the crack.
Really looking for ideas here. A new GM cylinder head is $400. thanks.
View attachment 203536 
This is all preliminary checking and I still want to pressure wash the head today and redo the developer test. Still wondering if it is worth having a machine shop do their own tests regardless of what i find? At this point I am tempted to just slap on a head gasket, button everything back up and live with it. Although re-torquing the head may result in elongating the crack.
Really looking for ideas here. A new GM cylinder head is $400. thanks.
View attachment 203536
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Tonyrodz
Resident Resident
I'd look for another head, or even a set. They're plentiful in the yards, unless this is your dd. Or even repair the crack.
randeez
Full Access Member
what did you find when you lifted the heads? head gasket obviously failed?
the updated valve covers just come with an internal baffle to help slung oil stay out of the pcv tube, not sure of outlet size but shouldnt be hard to adapt.
heads??? id say bring it to the machine shop and let them decide, they look at heads all day and would probably have a better idea of what may be acceptable and could prob tell you before doing any thing to it (spending money on it). machine shop may also have a head laying around, check craigslist...i wouldnt buy a new one from gm.
Unless your 110% sure headgasket was your issue, I wouldn't reuse the head, would suck to put it all back together just to have same symptoms all the gaskets, tty bolts, fluids youd have to buy again would have bought a new head
the updated valve covers just come with an internal baffle to help slung oil stay out of the pcv tube, not sure of outlet size but shouldnt be hard to adapt.
heads??? id say bring it to the machine shop and let them decide, they look at heads all day and would probably have a better idea of what may be acceptable and could prob tell you before doing any thing to it (spending money on it). machine shop may also have a head laying around, check craigslist...i wouldnt buy a new one from gm.
Unless your 110% sure headgasket was your issue, I wouldn't reuse the head, would suck to put it all back together just to have same symptoms all the gaskets, tty bolts, fluids youd have to buy again would have bought a new head
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OP
OP
The local engine shop said they will pressure test it for leaks. The charge would only be $25 if they find a leak. $150 if it's found to be ok. They would then continue to resurface..etc. If I chose...new valve guides and seats would bring it up to $250. My lifters, rockers, valves and Springs are A-ok.
They said they can hook me up with a another one if need be but my concern is that they may be used.
Not sure what Tony was recommending as far as repairing the head. From what I've read online cracks in cast aluminum heads are supposedly irreparable. GM even says to discard the entire head if found to be cracked.
They said they can hook me up with a another one if need be but my concern is that they may be used.
Not sure what Tony was recommending as far as repairing the head. From what I've read online cracks in cast aluminum heads are supposedly irreparable. GM even says to discard the entire head if found to be cracked.
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Tonyrodz
Resident Resident
I've never repaired a cracked head myself, I was just going under the assumption that a cracked aluminum head could be repaired. Depending on how bad the crack is, I don't see that it would be impossible--BUT--if it is cracked, I'd try to buy another head, if possible.
OP
OP
Definitely not impossible depending on the extent of the damage. A quick google search shows you drill and fill the crack with a screw. Supposedly it stops the progression of the crack.
Advance Auto has a refurbished head for about $230 after core return.
Advance Auto has a refurbished head for about $230 after core return.
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Tonyrodz
Resident Resident
Is that a bare head?
OP
OP
Nope. It Includes all valve hardware. It's delivery only.
Finished dropping off head at engine shop. It's $25 to test. $100 for exhange.
retiredsparky
Full Access Member
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Is it possible that you have Castech heads? They crack from bad design--reinforcing ribs left out which allows the head bolts to compress the head too much. One sign of this compression is a clean spot around the head bolt and slow leakage of coolant over several months usually. They are not repairable. The problem is inside the casting.
OP
OP
I don't have Castech heads. No logo underneath the roller rockers.
OP
OP
Apparently it doesn't matter. My local machine shop said it almost always happens over time to one of the heads.
OP
OP
Ahead of schedule, shoulda planned on throwing a cam in it
I thought about it but it's much more labor intensive than i realized. You need to remove the AC condenser and radiator for one. Then comes the dreaded stuck harmonic balancer, then water pump, timing set.... list goes on. For the money swapping in a 6.0 would make more sense.
OP
OP
Just an update. It has been a while to complete this project. Taking my time I guess. About 3-6 hours every weekend.
As it turns out most of the time I have spent making orders and waiting for shipments to come in. I have had to replace all 16 lifters, 5 push rods and 5 rocker arms, clean and sand both exhaust manifolds, clean and degrease everything, heads and remove and install all valves, have heads machined to .006 thousandths. Clean, pressure wash and do all that. Cleaning engine block deck took a long time using a razor blade, carb cleaner and wire brush. Also had to check all clearance measurements and replace oil dipstick tube.
I only have the rocker arm covers and intake left...plus all the little stuff. Shouldn't be more than a day or so left.
As it turns out most of the time I have spent making orders and waiting for shipments to come in. I have had to replace all 16 lifters, 5 push rods and 5 rocker arms, clean and sand both exhaust manifolds, clean and degrease everything, heads and remove and install all valves, have heads machined to .006 thousandths. Clean, pressure wash and do all that. Cleaning engine block deck took a long time using a razor blade, carb cleaner and wire brush. Also had to check all clearance measurements and replace oil dipstick tube.
I only have the rocker arm covers and intake left...plus all the little stuff. Shouldn't be more than a day or so left.
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CountryBoy19
Full Access Member
Good to see progress, I'm excited for you!
OP
OP
Yeah, I am excited too. Wanna start this up SO bad. Just having the heads off and removing the broken off exhaust manifold studs seems all worth it. Plus the fact it is going to run a whole lot better....AND get better mileage to boot.
It's supposed to be done today but I got all the way to putting on the alternator and found out that I threw away the alternator bracket bolts with the old head bolts. Heading on over to the hardware store.
I am going to change the oil and put back in the old coolant (filtered somewhat) so I can flush it again tomorrow. Here is what it looks like thusfar.
Your eyes aren't deceiving you. The alternator, water pump, hoses, throttle body and sight shield are newer. last owner a few years ago replaced water pump and I replaced the alternator 2 years ago. The whole engine was also lightly pressure washed just before replacing the intake manifold gasket 2 years ago.
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OP
OP
Well today was the day. Crossed my fingers
Make sure oil and filter was changed. Check. No gas leaks..Check. Battery connected. Check. Coolant...etc.
Ignition sequence in 5, 4, 3, 2, 1....
Wah.. wah.. waaaah!
Nooooo! It ran rough as ever with flashing CEL on ! Not now girl... What the heck did I not do right? It seemed like it was only firing on half the cylinders. Had to make a one mile trip to drop daughter off at dance class running rough as ever sitting in traffic with CEL..taking 30 seconds to pull out of an intersection going dog slower than a ww1 tank.
Got back home...scanned for codes. Got cylinder2, 4, 6 misfire and a whole bunch of coil codes. Well as it turned out the problem was staring at me right in the face. I forgot to connect the right bank coil packs to the harness connector! Shoot.. I connected it up prayed to the auto gods... I then cleared the codes and started it back up with crossed fingers. Vroom!! Yeah...sounds great...no more rough idle. Definitely seems like more power at higher rpms. There doesn't seem to be any fluid leaks anywhere and the exhaust is not leaking anymore. After about 4 weeks of taking my time i can finally call this project complete. Thanks everyone for the moral support and help!
Make sure oil and filter was changed. Check. No gas leaks..Check. Battery connected. Check. Coolant...etc.
Ignition sequence in 5, 4, 3, 2, 1....
Wah.. wah.. waaaah!
Nooooo! It ran rough as ever with flashing CEL on ! Not now girl... What the heck did I not do right? It seemed like it was only firing on half the cylinders. Had to make a one mile trip to drop daughter off at dance class running rough as ever sitting in traffic with CEL..taking 30 seconds to pull out of an intersection going dog slower than a ww1 tank.
Got back home...scanned for codes. Got cylinder2, 4, 6 misfire and a whole bunch of coil codes. Well as it turned out the problem was staring at me right in the face. I forgot to connect the right bank coil packs to the harness connector! Shoot.. I connected it up prayed to the auto gods... I then cleared the codes and started it back up with crossed fingers. Vroom!! Yeah...sounds great...no more rough idle. Definitely seems like more power at higher rpms. There doesn't seem to be any fluid leaks anywhere and the exhaust is not leaking anymore. After about 4 weeks of taking my time i can finally call this project complete. Thanks everyone for the moral support and help!
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Tonyrodz
Resident Resident
Great job
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