6.2 Overheating Woes

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Milblazer

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Well after finally completing my serpentine conversion I got everything buttoned back up and took my truck out for a drive today. First thing is it did not want to start. Had to cycle the glow plugs a couple times and push the accelerator all the way to the floor until it starts and then I have to rev it a few times so it stays running or I will have to restart the whole procedure of cycling the glow plugs. Anyway I took my truck out to the local post office (4 miles) after getting it started and by the time I was there the gauge was almost in the red. Seems to idle right around 220 degrees which is not okay for me.

So here is my plan of attack:

Swap out the new fan clutch for the old one to see if the new one is not kicking on at the right temp.

Swap out the new fan and clutch with the old ones, see where that takes me.

Swap out the new fan and replace it with the new one. Doubt it will do anything but I have to make sure.

I really need to do a compression test too. Maybe I'll swap out the heads so I can see if it the valves and I can get a look at the pistons. ****, I really should just rebuild the motor.
 

Milblazer

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Just to add it is in the low 40s and somewhat windy
 

Milblazer

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I realized that I cant test using the old clutch/fan because the new water pump is CCW rotation and the old pump is CW rotation.
 

Milblazer

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I've decided to pull the heads off as I believe I have a cracked head or bad headgasket because the truck overheats, there is blowby coming out of the dipstick tube, and white smoke out of the exhaust (primarily on the driver's side). I'm getting together a list of what I need to do this.

Head gaskets
Exhaust manifold gaskets
Head bolts
RTV for valve covers
High temperature thread sealant
Tap to clean up head bolt threads
 

marks86

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is it a brand new waterpump?
 

Milblazer

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New waterpump, thermostat, reconditioned radiator, new coolant
 

Milblazer

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Intake is pulled, injector lines are off, alternator and vacuum pump are off. Drivers side bracket is off. Fun thing happened when I was trying to get the pulley off of the power steering pump The little grooved ridges that the puller grips onto, half of those pulled away from the pulley itself. I tried using a 3 jaw pulley puller but that didnt work. I have no damn clue how to get that pulley off the pump now and that pisses me off because that pump has less than 50 miles on it and all new fluid. Now I'm going to have to pull it and probably replace the bugger unless I want to spend a **** load of time cutting the old pulley off. I hate when fixing one problem causes another.
 

Milblazer

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Think I found my problem.
 

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Milblazer

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Rusty cylinder head help

:banghead: Head gaskets were good it turns out. Now I need to figure out how to clean up the other set of heads I have. These are the new ones. I have cleaned up one, the other is still a bit rusty. Should I get these professionally cleaned up? Thanks
 

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350runner

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Looking good

Sent from the dust in front of you!
 

Stroked

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I probably wouldn't pay to get them cleaned up if it's just that combustion chamber. You could probably clean that up pretty good yourself without too much trouble.
 

Milblazer

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Thanks guys. What I'm using to clean the heads is just a straight razor blade and some very fine steel wool. I'll be getting some brake cleaner to help get everything squeaky clean before reassembling. Only thing i'm worried about with these new heads is that the valves are rusted shut (if you cant tell I am pretty clueless when it comes to cylinder heads). Also since these heads came with stainless steel gaskets i'm going to be looking into getting some of those. I have regular fel-pro ones, time to do some research and see what makes them different.
 

Milblazer

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Getting closer to buttoning everything back up. Heads are cleaned up, still have a few spots to go over again. Bad news is my precups are cracked. I know its a common thing but one head is cracked more than the other and it's making me want to swap those out while everything is apart so I wont have to do this again.
 

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Milblazer

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I have the heads reinstalled and torqued down. Pushrods are installed and im ready to put the rockers on. Im using the CUCV TM and it now says I have to rotate the harmonic balancer to a specific point and then install the rocker arms. Why do I have to do that?
 

Stroked

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I have the heads reinstalled and torqued down. Pushrods are installed and im ready to put the rockers on. Im using the CUCV TM and it now says I have to rotate the harmonic balancer to a specific point and then install the rocker arms. Why do I have to do that?

Hmm, it was a while back when I put mine together, but I don't remember doing that. I had my brother helping me and we used a GM service manual. Maybe he did it while I was working on something else.
 

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