Castech Heads Replacement

[DeePa]

All,

 

I have a 2004 Sierra 5.3 SLT with 140,000. I have owned since 68,000 (3 + years), and around 5000 miles ago.....

 

I had the tell tale castech signs...blue/white puff at startup, ticking lifters for first 30-60 seconds, sludge in my oil filter at the last oil change, and a coolant leak that could not be found.

 

I finally pulled the rocker arms and I do indeed have the castech heads. I do not think they are leaking badly, but I am replacing them. The motor is torn down to the block at this point. ONe head looked nice and clean, the other had a tarnish black substance stuck to everything. I do not see the clean area where the coolant leaked in, but I am replacing them no matter what at this point. All of the intake valves and spark plugs were a whiteish color. EX valves were black and full of carbon (obviously.) Do you think my heads may be OK? Maybe it was a head gasket issue? Even though I know in my ownership it has never over heated what so ever.

 

I have a few questions about the repair.

 

Should I install new lifters? If I do, do I have remove the knock sensors and valley pan cover? I RTV'd the crap out of the knock sensor plugs and do not want to take them out. I had the p0322 (i think) code for the corroded rear knock sensor.

 

I found an ebay guy with rebuilt 5.3 heads for 190 and free shipping. I want to call him tomorrow and make sure I am not getting castech heads back. I also think an 826 head would be better. Opinions wanted. I am sure they are reman's but I just need this running. All I need out of this truck is another 60,000. It is very well maintained besides driving the snot out of it.

 

I am also going to do the waterpump and upper/lower radiator hoses. After 140,000, its only a matter of time and the coolant is all drained out at the moment.

 

How do i drain the rest of the coolant from the block? On my 91 350 vette L98, i just pulled the knock sensor and all was well.

 

I am buying new fel-pro head bolts. Whats their torque? 65 ft #'s in 2 steps? THey appear to have sealant and/or loctite on the bottom. When I did my corvette heads, sealant was needed because the bolts threaded into water jackets. Is this the same case?

 

I plan on buying the FelPro head set kit. I found it on ebay for about 130.00 which is a lot cheaper than RA.

 

What spark plugs do you recommend? I am thinking a set of NGK Iridiums.

 

ANy help would be greatly appreciated.

 

Mike

[rdnkcpa]

All,

 

I have a 2004 Sierra 5.3 SLT with 140,000. I have owned since 68,000 (3 + years), and around 5000 miles ago.....

 

I had the tell tale castech signs...blue/white puff at startup, ticking lifters for first 30-60 seconds, sludge in my oil filter at the last oil change, and a coolant leak that could not be found.

 

I finally pulled the rocker arms and I do indeed have the castech heads. I do not think they are leaking badly, but I am replacing them. The motor is torn down to the block at this point. ONe head looked nice and clean, the other had a tarnish black substance stuck to everything. I do not see the clean area where the coolant leaked in, but I am replacing them no matter what at this point. All of the intake valves and spark plugs were a whiteish color. EX valves were black and full of carbon (obviously.) Do you think my heads may be OK? Maybe it was a head gasket issue? Even though I know in my ownership it has never over heated what so ever.

 

I have a few questions about the repair.

 

Should I install new lifters? If I do, do I have remove the knock sensors and valley pan cover? I RTV'd the crap out of the knock sensor plugs and do not want to take them out. I had the p0322 (i think) code for the corroded rear knock sensor.

 

I found an ebay guy with rebuilt 5.3 heads for 190 and free shipping. I want to call him tomorrow and make sure I am not getting castech heads back. I also think an 826 head would be better. Opinions wanted. I am sure they are reman's but I just need this running. All I need out of this truck is another 60,000. It is very well maintained besides driving the snot out of it.

 

I am also going to do the waterpump and upper/lower radiator hoses. After 140,000, its only a matter of time and the coolant is all drained out at the moment.

 

How do i drain the rest of the coolant from the block? On my 91 350 vette L98, i just pulled the knock sensor and all was well.

 

I am buying new fel-pro head bolts. Whats their torque? 65 ft #'s in 2 steps? THey appear to have sealant and/or loctite on the bottom. When I did my corvette heads, sealant was needed because the bolts threaded into water jackets. Is this the same case?

 

I plan on buying the FelPro head set kit. I found it on ebay for about 130.00 which is a lot cheaper than RA.

 

What spark plugs do you recommend? I am thinking a set of NGK Iridiums.

 

ANy help would be greatly appreciated.

 

Mike

 

I just went through the same thing with my 2004 Silvy 5.3

 

If you have a stuck lifter, replace the lifters. They are not too expensive and easy to do. You do not have to remove the valley pan cover, you can leave the knock sensors in place. Once you have the heads off there is a plastic piece inside the block that holds the lifters in place. Remove the plastic piece and you should be able to pull all the lifters out pretty easily. The new lifters slide right back in. Make sure you soak them in oil prior to putting in. They pump up much quicker that way.

 

Beware of the ebay heads, just my opinion. The castech heads develop porousity cracks. A lot of the online rebuilders cut the cracks out and weld a new chunk of aluminum in. If they use new castings most likely they are imported from China. If you plan on keeping the truck for a while find out where the castings come from. I'm not a fan of Chinese quality. I got my heads from a local machine shop, but paid a lot more than $190.00. The head casting were brand new, sourced from Canada. My old valves were reground to spec and put in the new head castings, along with the valve springs. They cost me $780.00 but if they fail I can return them to the machine shop where purchased and he'll warranty them. Good luck with that on the internet.

 

There are block drains if you get under the engine and look up you should be able to see them pretty easily.

 

The head bolts are torque to yield. I think they are 22 Foot pounds on the first past, then a 90 degree turn on the second pass. The two short bolts I think are a 50 degree turn. Buy yourself the shop manual for the truck from Helm. It was $135, but has all the torque settings and patterns. You also need the torque settings and pattern for the intake manifold, those settings are in inch pounds. The rocker's have a specific pattern that must be followed when torquing. The head bolds on this block do not go through a water jacket. Make sure you clean out the bolt holes real well before putting the heads back on. Once you get your old heads off, there is a plug on the passenger side head towards the back where a temp sensor would go if it was used on the drivers side, make sure you pull that plug out, you'll need to reinstall on the new heads. Also make sure you pull the head guide pins out of the heads and block. Buy a new set of exhaust manifold bolts from GM. Your old ones are toast. They are pretty cheap. The machine shop that did the heads provided the gasket kit, it is Fel-Pro. It had all the gaskets in it and seemed to work pretty well.

 

Hit Rich aka MS3DALE up for your water pump . He'll send you an AC-Delco that is OEM. For the spark plugs I used AC-Delco 41-110.

 

I put all new radiator hoses, plugs, wires, belts, and idler pulleys. I think I bought 3 new idler pulleys, they did wonders on quiting the noise down.

 

If you have sludge in the oil then most likely you'll need to also drop the pan and get all the junk out of the pan. Good luck.

 

This repair is not too bad, biggest PIA was getting the fuel line disconnected. Everything comes apart very easily and goes back very easily as well. I caught mine in time and my oil was sludge free.

[DeePa]

I have only noticed sludge one time, my last change, and I have been changing it ever since I owned the truck. I have under 500 miles on the oil in there now, and I will change it out when I am done with the repair and add AMSOIL sludge cleaner the next 3 oil changes. I feel I caught the problem very early and that the heads were not leaking badly, but enough to show the signs.

 

As far as lifters, if none are stuck, should I just run them? The GMPP ones I am looking at are like 140 a set, which isnt bad considering there are 16 of them. These are the same ones that I run in my 91 vette.

 

I spoke to the ebay seller and all of the heads he is selling are castech reman's. I found a local machine shop that can transfer all of my valves, springs, etc into a bare head which I would buy from GM. IF anyone has a part number for that, it would be very helpful. I will reuse the valve with a 3 angle valve job, but should I replace the springs? I'll ask the shop the same questions, just wondering what you guys who have been through this think.

 

I'll look for those block drain plugs. I have the Z71 option so I am sure that they are buried underneath the skidplates.

 

I'll buy a thread chase for the head bolt holes and clean them up good for the right Torque value. I'm not really sure what torque to yield is but I will go look it up and figure it out. A service manual is on the way also.

 

Thanks for the plug recommendation. I'll grab those.

 

Thanks for all of your help. ANy other info/comments/concerns are definately welcomed.

 

Mike

[jblakeney]

One of my gmt800's had ngks from the factorty with ngk numbering as well as GM. If I was pulling my heads off my truck I'd make sure I didn't end up with castech ones I put back. I would our a set if aftermarket ones one before that.

 

Felpro is felpro as long as it is the same part number, doesn't matter where you buy it.

 

You have two drain plus in the block one above the starter and one above the oil filter... takes a large hex key or bit.

 

Plugs, wires, thermostat, waterpump come to mind. As some things you will have to remove that are high wear, for your mileage.

 

Jbo

[rdnkcpa]

I have only noticed sludge one time, my last change, and I have been changing it ever since I owned the truck. I have under 500 miles on the oil in there now, and I will change it out when I am done with the repair and add AMSOIL sludge cleaner the next 3 oil changes. I feel I caught the problem very early and that the heads were not leaking badly, but enough to show the signs.

 

As far as lifters, if none are stuck, should I just run them? The GMPP ones I am looking at are like 140 a set, which isnt bad considering there are 16 of them. These are the same ones that I run in my 91 vette.

 

I spoke to the ebay seller and all of the heads he is selling are castech reman's. I found a local machine shop that can transfer all of my valves, springs, etc into a bare head which I would buy from GM. IF anyone has a part number for that, it would be very helpful. I will reuse the valve with a 3 angle valve job, but should I replace the springs? I'll ask the shop the same questions, just wondering what you guys who have been through this think.

 

I'll look for those block drain plugs. I have the Z71 option so I am sure that they are buried underneath the skidplates.

 

I'll buy a thread chase for the head bolt holes and clean them up good for the right Torque value. I'm not really sure what torque to yield is but I will go look it up and figure it out. A service manual is on the way also.

 

Thanks for the plug recommendation. I'll grab those.

 

Thanks for all of your help. ANy other info/comments/concerns are definately welcomed.

 

Mike

 

The machine shop should test the springs. If the springs are out of spec the machine shop should replace them. IIRC valve springs are not very expensive. I think I paid right around 140 for my lifters as well. I got them from the machine shop that did my heads. I don't recall what brand they were off the top of my head, but they seem to be working just fine. I replaced my lifters becuase I was getting a pretty bad lifter clack at start up due to the catech problem. I thought that was the solution. Right now I have a quiet valve train, all is good.

[DeePa]

I am ready to order a bare casting from GM. This is the part number I came up with from the catalog. 12578925

 

Is this correct? There is another one listed but it is much more expensive. Where is the best place online to purchase this?

 

Thanks,

 

Mike

[rdnkcpa]

I am ready to order a bare casting from GM. This is the part number I came up with from the catalog. 12578925

 

Is this correct? There is another one listed but it is much more expensive. Where is the best place online to purchase this?

 

Thanks,

 

Mike

 

Send a PM to MS3DALE, he'll hook you up.

 

Also, are you ordering 1 or both heads? My driver's side head was full of the DEXCOOL snot passenger side looked brand new. However after pressure testing both heads were cracked.

[DeePa]

I ordered both heads. The drivers side was bad with the butterscotch/tar in the valve cover. The pass side looked good, but I am not risking it. I plan on keeping the truck another 60k so i want this done correctly.

 

Rich really helped me out with parts. Thanks again.

 

I'll let you guys know when it is all said and done. Heads will be in Tuesday, probably back from the machine shop on Friday, and then I can start reassembly. I bought a service manual so I should be set.

 

One thing i noticed is that the manual said the alternator bracket must be removed for reinstallation. It came off just fine leaving that bracket on, but pulling the bolts that support it to the head.

 

I decided not to do the hoses, but I am doing the water pump and AC belt with the 3 tensioners. The serp belt is almost brand new. I may go run to the store at the last minute for a set of hoses, just couldnt justify it at the time i guess. THey both feel very good and look good too.

 

Last thing on my list is a trip to the hardware store to get a set of Stainless Steel exhaust manifold bolts. That should cover all of my parts list.

 

Thanks,

 

Mike

[dlewis1111]

I ordered both heads. The drivers side was bad with the butterscotch/tar in the valve cover. The pass side looked good, but I am not risking it. I plan on keeping the truck another 60k so i want this done correctly.

 

Rich really helped me out with parts. Thanks again.

 

I'll let you guys know when it is all said and done. Heads will be in Tuesday, probably back from the machine shop on Friday, and then I can start reassembly. I bought a service manual so I should be set.

 

One thing i noticed is that the manual said the alternator bracket must be removed for reinstallation. It came off just fine leaving that bracket on, but pulling the bolts that support it to the head.

 

I decided not to do the hoses, but I am doing the water pump and AC belt with the 3 tensioners. The serp belt is almost brand new. I may go run to the store at the last minute for a set of hoses, just couldnt justify it at the time i guess. THey both feel very good and look good too.

 

Last thing on my list is a trip to the hardware store to get a set of Stainless Steel exhaust manifold bolts. That should cover all of my parts list.

 

Thanks,

 

Mike

 

Are those heads aluminum? I ask because if you put stainless steel bolts into aluminum you may create a corrosion problem caused by dis-similar metals contacting each other. This will in turn seize the bolts into place. Not sure if this is true in your case, but just be aware if not already. good luck with the reinstallation

[flhusa1]

if this is the case just use a good quality anti-seize compound.

[rdnkcpa]

For the exhaust manifold bolts, get the GM bolts. They are cheap and come with the locktite already on them. I think I paid around $23.00 for the set.

 

I don't know what advantages the stanless bolts would get you.

[DeePa]

For the exhaust manifold bolts, get the GM bolts. They are cheap and come with the locktite already on them. I think I paid around $23.00 for the set.

 

I don't know what advantages the stanless bolts would get you.

 

 

Stainless are less likely to seize due to heat if I am informed correctly. I do have a very good quality high temp antisieze that I purchased from McMaster so I should be all set there.

 

My new heads are at the machine shop getting all of the goods swapped over. I am hoping to install Friday/Saturday. I have a new H2O pump also but I decided not to replace the hoses. I may end up just buying them at the last minute.

 

Thanks for all of your help.

 

Mike

[Black02Silverado]

DeePa, you have gone this far, I would go ahead and change the hoses and be done with it. If you have my luck as soon as you get it all done and go about 10k miles of driving time one of the hoses would let loose. Plus it could happen at it's time of choice, like when you are in the middle of nowhere and it is 2 in the morning an nothing is open.

[rdnkcpa]

DeePa, you have gone this far, I would go ahead and change the hoses and be done with it. If you have my luck as soon as you get it all done and go about 10k miles of driving time one of the hoses would let loose. Plus it could happen at it's time of choice, like when you are in the middle of nowhere and it is 2 in the morning an nothing is open.

 

Upper and lower radiator hoses should be around $50.00 or so. I forget how much they were, but they are not too bad. I had to replace the bleed air hose. It runs from the intake to the pipe that runs between the heads on the front of the engine. I was impatient and cut the end so I could get it off.

 

I also replaced the hose clamps with all stanless steel clamps. Next thing to be replaced are the heater hoses. I'll do those this summer sometime.

[DeePa]

Well I made some progress at the repair yesterday and last night. The rain kind of slowed me down. Have about 5 hours into the reassembly so far, not counting cleaning up gasket surfaces and such.

 

All is going really well. The lifters went in really easy, heads are on and torqued, all pushrods installed and rockers adjusted, valve covers, plugs, wires, coil packs all installed and tight. Was able to do the waterpump and rad shrouds/fan/belts/hoses and the alt is back in. Exhaust manifolds are bolted to the heads but not yet bolted to the front y pipe. I also replaced all pulleys and the AC Belt. The Serp belt was only 6 months or so old and was fine.

 

All I really have left is the intake and airbox install with the routing and connection of all the electrical stuff. Jack the truck up, install oil drain plug and filter, finish the ex manifolds, throw a couple of shrouds back on, then drop it and fill with oil and coolant and see if it decides to start and run.

 

It really wasnt all that hard, just time consuming and I finally bought an air ratched which speeds up the process a lot. Hardest thing was being careful not to damage or break anything. Torquing the heads takes some patience because you are in an akward position to tighten the bolts and they get pretty tight at the 3rd pass of 90 degrees.

 

I found it funny that my new set of bare heads were manufactured by castech. They had the marking on them just like my old heads. I really hope it is an updated design...As long as I get 60,000 out of them I am happy.

 

Thanks,

 

Mike