Check to upper radiator hose for hardness!

 

I just checked the hose and was kind of hard but I could still squeeze it. I also took the cap off the overflow tank and there was still a little bit of pressure in there. Does that confirm its the head gaskets?

 

Somewhat firm hose, a new $10 tank cap is worth a try.

 

My hose has been hard since late spring early summer. My low coolant light came on back on Nov 10th. Added about 1/2 gallon of coolant and H20. Hasn't come on since. I know mine needs doing, but I haven't driven much this fall as I had knee surgery. Hoping that once I am close to 100% I can plan to get this done. Not very Mechanically inclined these days & I don't have space to do this type of work. Not driving it much these days and keeping track of fluid level in the overflow. If I can get by until late January or Feb, I'll get the gaskets and some other work done then.....

 

Ok so I refilled the coolant to the correct level and drove the truck about 30 miles. No overflowing coolant or bubbles in the tank so I really don't know what to think now. The water temp holds at about 180 degrees after it warms up and does not fluctuate.

 

Mine only leaked under heavy boost. Some mornings it was only somewhat firm, others it was rock hard and coolant would explode out of the resovoir after removing the cap. I didn't have any other symptoms, it ran nice and smooth and didn't overheat. Not having many symptoms is pretty common. When I disassembled, I saw where number 7 was leaking into the rear water jacket.

 

aren't you supposed to squeeze the upper radiator hose when cold in the morning and if its hard it needs HG!

 

Yes, that is what I have been told, from here and other sources.

 

What about this one. Coolant coming out of the overflow tank. Heater blows cold. Until temp reaches 220+ then goes back down. When temp goes to normal. Coolant stops coming out of burp tank. Thermostat has been changed. Worked on ford diesels for ever and switched over to Chevy's less headaches and way better truck. Any suggestions on my problem

 

Dunno Boogerfide........maybe somebody with some more knowledge can chime in.....

 

Turned out to be head gaskets. The top radiator Jose was hard after sitting all night and confirmed with combustion tester. Thanks

 

Mine held pressure for days and kept puking coolant so its the head gaskets. I just started taking it apart today. I bought a kit with grade C gaskets and ARP head studs. Once I get the heads off what exactly should I have the machine shop do to them? Any advice or tips on the whole job?

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Yeah jay make sure the machine shop knows what they are doing. me sure they know what the specs are before they start milling your heads. I.E. just sent a set of ford heads in for one of my customers. And they machined the heads .027 and .019 which the max on them is .010. So now I have paper weights. Can't even get a core out of them for new head purchase.

 

You would pretty much want the machine shop to recondition the head.. Have them pressure tested and mag'd for cracks, decked, have the valves lapped, have them check valve guides and put new guide seals in. They should know the routine if their a reputable speed shop. IIRC they cannot take more than .0079 off the head before they're junk, but they should know that. I just had mine done and they charged me around $300 bucks.

Also be sure to back off on the valve lash before removing the rocker shaft. When reinstalling use the info merchant has to offer via pdf file. Heres the link:
http://merchant-automotive.com/tech/valveadjustment.pdf


if you have any questions we should be able to help

 

Thanks, that really helps. What should I set the valve lash at? I read people put it anywhere from .009 to .013. Since I have everything apart and the whole front clip off, what mods should I do and what parts should I replace? So far I'm doing a full EGR delete, PCV reroute, down pipe, high flow manifold, water pump and thermostat.

 

Sounds like your on the right track, I did a new fpr while mine was apart also. Valve lash should be set at .012. Some say a little tighter to quiet down the motor but that's your call, I set it at .012 like GM says.

A few tips on tear down:
the power steering pump can just be unbolted and pushed aside, no need to disconnect any lines.

I labeled everything on how it came out, especially the push rods, injectors, rocker shafts and valve bridges.



When removing the heads, unbolt the 2 upper bolts and 2 lower nuts from the driver side y-bridge to intake runner and remove the passenger side head first with intake runner and y-bridge still attached and without the exhaust manifold attached (you can if you want but its difficult with the dipstick going through it)


Then remove the driver side head with the intake runner and exhaust manifold still attached.

when unbolting the heads, take the 4 smaller upper bolts out first, then start in the center of the head and work your way out. I'm not sure if it is totally necessary but I feel like it'll help prevent warping when removed.

 

Chevytothefloor has some good tips. And it is important to stay organized when doing this. As far as the push rods and injectors staying in the same order, it really don't matter. I have been building engines for 19 years and I did this at first. But honestly it don't matter. Just make sure everything is in spec. I.E. push rod run out. .008". That's when you take a feeler gauge and roll the push rod over it. So don't get your self all jacked up cause something got put out of order. I got manuals if you need them.

 

Definitely stay organized during dis-assembly as Boogerfide said. Keep us posted on your progress!

 

Well after working on it for a few hours each night after work, I removed everything needed to pull the heads except the manifolds. I read its better to unbolt the passenger side manifold from the head and let the drivers side attached but I cannot seem to get the bolts out on the where the manifold connects to the up pipe. Could I just double nut the studs to get them out of the head and leave the manifold? I bought a high flow manifold and need to install it. Is it easier to remove the drivers side manifold after the head is off?


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Ok so I just got the heads off and I can't really tell where the gasket was blown but maybe that's because I don't know what I'm looking for. Anyway, what should I do to the block to prepare it for the new gasket and is there anything else that should be done before I install the heads? Also, the bottom of my overflow tank was covered in oil so I'm guessing that was due to the head gaskets?

Here are some pics

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For the block and heads GM Service Bulletin says to use 600gritt wet/dry sand paper and a moisture dispersing fluid (WD40).

Get you a piece of square tubing or something very firm that you can wrap the sand paper around. Make sure its the sane length as the heads/block is wide (6-8")Work front of motor to back of motor til surface is clean. Use plenty of WD40. Use of scotch brite or Roloc's will ruin your motor. Just keep it moving, keep it wet, and keep it even.

I just done the same thing to my LLY with Grade C's & Studs. Took about 30min for each section. Just be sure to stuff clean rags or something in the lifter valley to keep debris from falling in there. Id make a few passes, wipe it clean, then repeat with lots of WD40 on the block/heads and sandpaper.

 

Thanks that helps!

Are you doing any other mod's or replacing of parts while y have the top end apart?

I'm doing an EGR delete, down pipe, high flow manifold, water pump, thermostat, PCV reroute and of course ARP head studs

 

Are you doing any other mod's or replacing of parts while y have the top end apart?

 

I figured while i had mine down it would be a good time to do driver side LML manifold and a few other things. I wanted to have my water pump welded and replace my passenger up+pipe but time was my enemy

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Horrors of the EGR! This stuff is like tar and is on there so thick! I can't wait to see how much better my truck will be running with all this crap out of the intake.

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clean the injector holes prior to putting the heads back on. This will give you a nice clean sealing surface for the copper washer. I used a little vaseline on the injector o-rings for re-installation. Follow Merchants instructions for finding TDC on the right cylinders. I set my valve lash to 10 thou. definitely runs quieter.

 

Holy Popballs Batman! That looks gross! I guess mine is going to look like that when my heads come off. Good list of mod's to do. ARP head studs are a no brainer....