Blown Head Gasket repair cost?

[Scooterwrench]

Scooter, what temp Tstat are you running in your truck? I’ve been told that 180 is what’s recommended. But if you have proof positive otherwise, I’ll give it a try

195deg. If you run a cooler T-stat on these trucks the ECM thinks the engine hasn't gotten up to operating temp and causes it to run rich. Hurts your pocket at the pump. A trick I use and many others is to drill a 3/32" hole in the T-stat flange. It will drop the temp a couple deg. but the main reason is to bleed air off and make it easier to fill the system with the engine running.

 

[Grandpa_truck]

195deg. If you run a cooler T-stat on these trucks the ECM thinks the engine hasn't gotten up to operating temp and causes it to run rich. Hurts your pocket at the pump. A trick I use and many others is to drill a 3/32" hole in the T-stat flange. It will drop the temp a couple deg. but the main reason is to bleed air off and make it easier to fill the system with the engine running.

Very interesting thanks! I’ll have to pick one up

 

[Schurkey]

drill a 3/32" hole in the T-stat flange.

Actual thermostat engineers do not drill gigantic holes in the flange.

At most, the Robertshaw thermostats have a tiny stamped vent. Plenty big enough to "bleed air" during cooling system service, not big enough to affect the running temperature, or to slow warm-up.

1/8 or 3/32 3/16 drill bit compared to Robertshaw vent size and #72 drill bit.

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[Scooterwrench]

Actual thermostat engineers do not drill gigantic holes in the flange.

At most, the Robertshaw thermostats have a tiny stamped vent. Plenty big enough to "bleed air" during cooling system service, not big enough to affect the running temperature, or to slow warm-up.

1/8 or 3/32 drill bit compared to Robertshaw vent size and #72 drill bit.

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3/32"(.09375) not 1/8"(.125) or 3/16"(.1875)
If you're gonna be a grumpy old fart at least get your measurements right.

 

[PlayingWithTBI]

195deg. If you run a cooler T-stat on these trucks the ECM thinks the engine hasn't gotten up to operating temp and causes it to run rich. Hurts your pocket at the pump.

You can run a 180° but, you'll need to tune for it, as mentioned above. Plus you can add a couple degrees of SA to it.

 

[Road Trip]

Mine never moves past the cold line..Used to before swapping thermostat,radiator cap and water pump.....
Was under the assumption this means my system is operating normally?
Just sits around @)@* or lower usually....Unless I'm stuck in idle like I was at landfill for 30 minutes...climbed to 225* before I got moving...

Hello scott2093,

Across several vehicles my overflow tank expectations have been conditioned to seeing the following:

1) Before starting vehicle: Coolant level right at sharpie marker. (Full Cold line)

2) After driving ~10 minutes or so, the level in the overflow tank is higher than the Full Cold line.

3) After returning to home base, right after shutoff coolant is still above Full Cold line.

4) After cooling off completely, coolant level has returned back to Full Cold line.

If I'm not seeing any water level movement, this normally means that the overflow tank
doesn't have a watertight/airtight connection to the radiator. Which can actually lead to
a false sense of security in coolant land, for you might be losing coolant through a
marginal connection/split in the line, so after the coolant gets hot, dumps a little
coolant overboard, and then when the system cools down, *air* gets sucked back
into the radiator.

See if you can't get that overflow tank securely coupled to the radiator. And once you
are 100% sure that zero coolant is being lost, and 100% sure that no air is being
sucked into your cooling system, then consider upgrading your clutch and fan
package from wherever you currently are to whatever L31MaxExpress is advocating.
(11 blade and matching clutch?) And do you have the original fan shroud in place?

And when the fan/thermostatic clutch kicks in, is 100% of the air pulled through the
radiator, or are there any places where the shroud allows air to bypass the radiator
from the sides? In English, these Texans have persuaded me that you don't have to
watch the temp gauge climb just because you are stuck in traffic.

Don't get me wrong, for I've fought the 'wants to overtemp' fight many times over
the years, but every time once I put the laser focus on the coolant consumption,
fan/clutch performance, and air mgmt. optimization, my cooling issues go away.

For what it's worth --

 

[Schurkey]

3/32"(.09375) not 1/8"(.125) or 3/16"(.1875)

Mia Culpa. Somewhat fixed in previous post.

If you're gonna be a grumpy SENILE old fart at least get your measurements right.

FIFY.

 

[scott2093]

See if you can't get that overflow tank securely coupled to the radiator. And once you
are 100% sure that zero coolant is being lost, and 100% sure that no air is being
sucked into your cooling system, then consider upgrading your clutch and fan
package from wherever you currently are to whatever L31MaxExpress is advocating.
(11 blade and matching clutch?) And do you have the original fan shroud in place?

Will check. Yeah everything used to work where the overflow tank would rise and then fall back to the cool level before installing the new water pump and thermostat.
I check my radiator (cold) often and it's right at the very top every time and the overflow just doesn't budge from the cold mark. Even after lots of driving.. Will put some serious focus on it. Maybe it's sneaking some action in when I'm not paying attention but I'm fairly certain nothing is going on.
Yes original fan shroud is in place.

 

[Road Trip]

Will check. Yeah everything used to work where the overflow tank would rise and then fall back to the cool level before installing the new water pump and thermostat.
I check my radiator (cold) often and it's right at the very top every time and the overflow just doesn't budge from the cold mark. Even after lots of driving.. Will put some serious focus on it. Maybe it's sneaking some action in when I'm not paying attention but I'm fairly certain nothing is going on.
Yes original fan shroud is in place.

Well, the expansion variable may be due to now smaller temp swings in your cooling system? Obviously,
a system that sits rock-solid at 195° isn't going to push as much coolant into the expansion tank
as the same truck getting up to 225+ degrees due to a cooling system working with suboptimal
components?

Even so, I'd expect to see some movement. Good on you for paying attention to your cooling
system like this. A bad overheat can really shorten the useful life of an engine, so it makes sense
to ensure the cooling system can move more BTUs to the atmosphere than the engine can generate.

Here's to cool runnings...

 

[scott2093]

Well, the expansion variable may be due to now smaller temp swings in your cooling system? Obviously,
a system that sits rock-solid at 195° isn't going to push as much coolant into the expansion tank
as the same truck getting up to 225+ degrees due to a cooling system working with suboptimal
components?

Yes. The scenario of sitting at a creeping idle for over 30 minutes and reaching 225 at the landfill was when I became more suspicious because when I arrived back home I checked the overflow and it was still at the cold line. I thought for sure it would have had some action?
I realize the temperatures are within safe range but I'm not convinced I wouldn't have pulled over and shut the truck down had I not got moving 10 minutes later. The trajectory was a steady climb to 225 and maybe 227..... really felt it was going to continue.

The truck stays around 202 usually. 195 t-stat..... it'll drop down when moving but it doesn't cycle like it used to. It's more of a, when the truck is moving thing. If it isn't moving like at decent speeds , it'll definitely camp around 202-204....
it's very different behavior than I've ever been used to but who knows, maybe I've been used to less than optimal...
will figure it out....

Surely if I got a bunk water pump, things would be much worse and obvious...?