6.0/4L80e swap running hot!

Well guys about a week ago I took the plunge and pulled the 5.3/4l60e out, only to replace it with a 6.0/4l80e. I stuck a TR Blower cam in for good measures and a week later it was finished. I topped all my fluids off then drove uptown only to realize that my coolant temperature sensor was bad. I got almost all the way home before it died on me and I had to push it a couple hundred feet into the driveway. Right before it shut off I heard a valvetrain noise which was probably due to the low oil pressure since my truck was running so hot; my truck was also steaming out the exhaust really bad. The next morning I pulled the coolant temp sensor and saw that no water came out (air bound?).. so I cranked the truck up until water started coming out the sensor port. I put the new coolant temp sensor in and filled the coolant up to its correct level. It was still steaming really bad out the exhaust so I went and bought a bottle of Blue Devil treatment that's meant for sealing head gaskets and warped heads. Well believe it or not the exhaust doesn't steam anymore!! It was about $65 for a bottle and it mixes with coolant unlike most sealants that you have to flush out after treating. I let it idle for about an hour and it was staying right around 210 degrees without the thermostat. I drove it probably five miles (still without the stat) before it started getting hot again. I pulled over to let it cool and once it was cool I made it all the way home just as the temp was starting to climb again. I then heard that our trucks won't stay cool without the thermostat so I put that back in. I disconnected the crossover tube at the radiator and started up the truck to get more air out of the cooling system and also make sure the water pump was working. Once the t-stat opened up water was spitting out decently so I filled the radiator and crossover tube back up and connected them. I drove it down the road only to find out it was getting hot again. I have no idea what it could be?? It seems my water pump is working and belt isn't slipping.. but it is almost like the coolant isn't circulating probably. I'm not sure where to go from here.

Thanks,
Trevor

I would be worried about the engine. if it actually quit on you thats not good. (like you didnt know that right? lol). sounds like there may be an air pocket in the cooling system. what type of fan are you using? how many miles on the rad?

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Originally Posted by Wilde Racing

I would be worried about the engine. if it actually quit on you thats not good. (like you didnt know that right? lol). sounds like there may be an air pocket in the cooling system. what type of fan are you using? how many miles on the rad?

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Yeah, I'm worried about the engine. The radiator is a 34 inch I bought new last december when I put the 05 up truck e-fans on.

Are you sure both fans are coming on high? is the A/C on?

Yeah both fans are cycling right and when a/c is on the relay kicks them on high.

I would never recommend a "stop leak" for a head gasket, much less anything else. Sounds like you need to invest in a compression tester my friend.

I would check for air bubbles in the system.

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Originally Posted by r6z4o6

I would never recommend a "stop leak" for a head gasket, much less anything else. Sounds like you need to invest in a compression tester my friend.

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Well it's not exactly your conventional "stop leak".. Unlike most agents out there Blue Devil is a thin liquid that forms a chemical reaction with water when heated and creates a bonding gel that seals up leaks caused by blown head gaskets or warped heads(not sure if that's what happened). I've heard it used to be more of a commercial product and my dad used it in his isuzu box truck with great results so far. Even though it says it permanently seals, I'm sure results are temporary especially in a boosted application.

I would check for air bubbles in the system...

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Originally Posted by pl4yboy

I would check for air bubbles in the system...

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I pulled the crossover tube off while running and air came out.. I put it back on but still feel like there's air in the system. A buddy that works at GM said that the best way to get air out is to vacuum the system but that requires a special tool or getting the dealership to do it. I think i might get a pvc pipe and install it in the middle of the crossover tube (since it's the highest point of the system) and make a pressure release valve into the pvc pipe.. I would keep the valve open until coolant is steady streaming out.

Anybody think this would work? Or know a better way to get air out?

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Originally Posted by ThunderBolt

I pulled the crossover tube off while running and air came out.. I put it back on but still feel like there's air in the system. A buddy that works at GM said that the best way to get air out is to vacuum the system but that requires a special tool or getting the dealership to do it. I think i might get a pvc pipe and install it in the middle of the crossover tube (since it's the highest point of the system) and make a pressure release valve into the pvc pipe.. I would keep the valve open until coolant is steady streaming out.

Anybody think this would work? Or know a better way to get air out?

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Fill it to the top with coolant with the vehicle running. The air bubble will likely end up in the crossover. Squeeze the crossover in a pumping manner until the bubble is pumped out. Keep filling the system as it runs down. EVENTUALLY, the bubble will come out.

park it on a hill, engine off, with the front end higher than the rear, take the air bleed hose off, remove the upper radiator hose from the radiator, pour water into the hose until a steady stream of coolant comes out of the air bleed hose fitting on the engine side. Reconnect everything.

Hope u get everything right

You need an air lift...yes, what we have at the dealer. Then again, it's prolly hurt.

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Originally Posted by pl4yboy

Fill it to the top with coolant with the vehicle running. The air bubble will likely end up in the crossover. Squeeze the crossover in a pumping manner until the bubble is pumped out. Keep filling the system as it runs down. EVENTUALLY, the bubble will come out.

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Originally Posted by RedHeartbeat

park it on a hill, engine off, with the front end higher than the rear, take the air bleed hose off, remove the upper radiator hose from the radiator, pour water into the hose until a steady stream of coolant comes out of the air bleed hose fitting on the engine side. Reconnect everything.

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I tried both of these methods but it's still overheating. I even found a good article about the GM coolant fill procedures which RedHeartbeat was describing.. We've had complaints of overheating on some late model GM truck engines; any clue why this is happening?: Engine Builder

I'm going to take the water pump off and check it out; something tells me there is something blocking my water passages not letting it circulate properly.

I just took the water pump off to inspect it and everything looked okay, and there was nothing blocking the water passages. Just to be on the safe side I put the water pump off of the 5.3 on because I knew that it worked but still no luck. This truck just won't stay cool!!

How hot is it getting. 220 230 240? If the truck only gets hot while driving sound like the engine has issues. The fact that it got so hot it died says it most have been really hot.
Does the truck smoke any after it cools down and you restart it.?

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Originally Posted by Turbo6.0L

How hot is it getting. 220 230 240? If the truck only gets hot while driving sound like the engine has issues. The fact that it got so hot it died says it most have been really hot.
Does the truck smoke any after it cools down and you restart it.?

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First time when it died the coolant temp sensor wasn't working, so it had to get really hot and I didn't even know it. It did steam a lot until I put the Blue Devil treatment in. Motor doesn't steam out exhaust anymore but it does steam a little out of the valve covers.. feels a little rough to me but maybe its the cam. It will get as hot as you will let it, although I shut it off when it gets around 230.

Compression test your cylinders first.
Are your fans turning the right direction?
Any water in your oil?

I don't think it's air bubbles.
That may have been it in the beginning, but i'm going to say you have a multiple problems now. You have an even BIGGER problem with the engine, yet you haven't tried to figure out what could have happened when it got so hot that it turned itself off. You sure are working hard at getting an airbubble out to fix it all, but.....

Seriously though, running rough, overheats, and steam out the valve covers? Does that really sound like an air bubble to you, or are you just avoiding the possibility of headgasket or worse in the hopes that it will go away?

I am not trying to be an a$$. Steamy exhaust and valve cover are not symptoms of "air bubble." I think you know what it is, so why not look into that? The Blue Devil is just making you feel better about a problem it can't permanently fix.

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Originally Posted by r6z4o6

Compression test your cylinders first.
Are your fans turning the right direction?
Any water in your oil?

I don't think it's air bubbles.
That may have been it in the beginning, but i'm going to say you have a multiple problems now. You have an even BIGGER problem with the engine, yet you haven't tried to figure out what could have happened when it got so hot that it turned itself off. You sure are working hard at getting an airbubble out to fix it all, but.....

Seriously though, running rough, overheats, and steam out the valve covers? Does that really sound like an air bubble to you, or are you just avoiding the possibility of headgasket or worse in the hopes that it will go away?

I am not trying to be an a$$. Steamy exhaust and valve cover are not symptoms of "air bubble." I think you know what it is, so why not look into that? The Blue Devil is just making you feel better about a problem it can't permanently fix.

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Fans are turning in the correct direction and there isn't any water in the oil. I'm convinced that air was in the system at first and that's why it ran really hot.. also the malfunctioning coolant temp sensor which is why I didn't realize it was hot at first. The first time when it ran really hot it had to damage the headgasket or warp the head.. I mean the oil was so hot it was barely holding oil pressure resulting in valvetrain noise. It didn't run very long like that so hopefully nothing is damaged internally. The Blue Devil did stop it from steaming out the exhaust; however, I know that it cannot permanently fix the problems I have. I'm hoping that it will only take a couple of head gaskets to fix instead of the heads being warped. Wouldn't you say the gaskets would blow or burnout before the heads would be warped? And if the heads were warped, wouldn't you think the motor would skip more than being just a little rough?

Your running no stat? No stat usually makes the coolant flow too fast and has no time to cool in the rad. I didn't really read the whole thing, just saw no stat.

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Originally Posted by ThunderBolt

Fans are turning in the correct direction and there isn't any water in the oil. I'm convinced that air was in the system at first and that's why it ran really hot.. also the malfunctioning coolant temp sensor which is why I didn't realize it was hot at first. The first time when it ran really hot it had to damage the headgasket or warp the head.. I mean the oil was so hot it was barely holding oil pressure resulting in valvetrain noise. It didn't run very long like that so hopefully nothing is damaged internally. The Blue Devil did stop it from steaming out the exhaust; however, I know that it cannot permanently fix the problems I have. I'm hoping that it will only take a couple of head gaskets to fix instead of the heads being warped. Wouldn't you say the gaskets would blow or burnout before the heads would be warped? And if the heads were warped, wouldn't you think the motor would skip more than being just a little rough?

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Usually head gaskets go becuase its warped. OR lifted basicly a temp. warping issue.
Might ought to pull the heads and check it out before something expensive lets go?

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Originally Posted by tanz45

Your running no stat? No stat usually makes the coolant flow too fast and has no time to cool in the rad. I didn't really read the whole thing, just saw no stat.

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I took the t-stat out to run the Blue Devil treatment, but I put it back in after I was done.

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Originally Posted by Turbo6.0L

Usually head gaskets go becuase its warped. OR lifted basicly a temp. warping issue.
Might ought to pull the heads and check it out before something expensive lets go?

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So your saying chances are my head gasket blew because my heads are warped?
Or because the gasket itself is warped?

I will tell you this, and this goes for ANYONE pulling heads with the slightest possibility of gasket/head issues. If you do not remove the heads and take them to a machine shop to get checked, they WILL be warped when you put them back on with new head gaskets and nothing will have changed lol. Murphy says so.

As far as the motor running more rough than it is, you are talking about something that has infinite degrees of being "out", blown, or warped. A water pump is good, or bad.(or failing) A head gasket/head can have so many degrees of failing, maybe it causes a big problem, maybe it doesn't. Depends on the severity...which is impossible to tell from the outside looking in.

When the rad is filled up with the proper amount of water, can you see any "steamy bubbles" or anything coming out? Refresh my memory, does your radiator have a cap or is the cap on the filler bottle thingy? Did you play with the heater any, you should def put it to HOT to let the water go into the heatercore.(once the headgaskets have been addressed) Is that the same radiator that was cooling the truck before?

You should do a compression check.

EDIT: Are you running the turbo setup right now?

My truck has the cap on the overflow tank and when the cap is off it does make "steamy bubbles" which shows it is presurizing.

The heater acts funny though.. sometimes it will blow really hot air then all of a sudden blow cool air. Not sure what's up with that..(maybe air in the heater core?)

Yes, same radiator as before and its a 34 inch. Also I am running the turbo setup.

Compression test is a waste of time in this instance. Do a block test and if it fails then do a leak down.

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Originally Posted by ThunderBolt

My truck has the cap on the overflow tank and when the cap is off it does make "steamy bubbles" which shows it is presurizing.

The heater acts funny though.. sometimes it will blow really hot air then all of a sudden blow cool air. Not sure what's up with that..(maybe air in the heater core?)

Yes, same radiator as before and its a 34 inch. Also I am running the turbo setup.

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You have a blown head gasket or cracked head or block. Steam bubbles are a small clue (can be caused by an airlock) but the heater doing that is combustion in the cooling system hence no need for a compression test....block test will prove exhaust gases in the radiator. If from there you wanna know which cylinder it is and where the leak is leaking into...do the leak down test. Compression tests are only good for the START of misfire diagnosis.

Well I took the heads off monday and saw a few bad spots on the gaskets. I went to a machine shop to get my heads checked and sure enough they were warped! Got them resurfaced and I also leak checked the valves. Finally got it running tonight and.. so far so good.. it's not overheating like it did before. Hopefully if the rain slacks off I'll be able to drive it more tomorrow. Thanks to those who helped.

Trevor

Hope its fixed man