How hot to warp the head?
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How hot to warp the head?
With spring in the air, and the ever present D series head gasket issues, does anyone know just how hot the engine has to get to run a serious risk of warping the head?
In the winter my D16Y8 typically runs around 175-185f. In the summer with the A/C on, the fans keep the water temp under about 205-208f.
With a leaky head gasket and running low on coolant I have seen 220-225 max. I don’t know if the head is warped as it’s still being driven. I’ll be changing in a week or two and I’ll let you know if it’s still flat or not.
Does anyone know, or is there a stated “max safe operating temp” for our engines, or aluminum engines in general?
TIA
Sacto
In the winter my D16Y8 typically runs around 175-185f. In the summer with the A/C on, the fans keep the water temp under about 205-208f.
With a leaky head gasket and running low on coolant I have seen 220-225 max. I don’t know if the head is warped as it’s still being driven. I’ll be changing in a week or two and I’ll let you know if it’s still flat or not.
Does anyone know, or is there a stated “max safe operating temp” for our engines, or aluminum engines in general?
TIA
Sacto
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Re: How hot to warp the head?
no...
when most find out it is too hot, it was too hot... Need to look at the roads to drive... can't be full time looking into the temp gauge (which is not that accurate)
when most find out it is too hot, it was too hot... Need to look at the roads to drive... can't be full time looking into the temp gauge (which is not that accurate)
Last edited by sdaidoji; Mar 26, 2018 at 06:16 PM.
If you think a good mechanic is expensive, try hiring a bad one
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The head should be checked every time it's removed, period.
Gauges lie.
Owners/drivers lie.
Precision measurement tells the truth
Gauges lie.
Owners/drivers lie.
Precision measurement tells the truth
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It’s going to the machinist this week for checking/milling and new stem seals, I was just wondering out of curiosity how hot and “average” aluminum head has to get to warp, or how much heat the d series heads can tolerate.
I suppose, if it’s low on coolant and the temp gauge is sayin +\- 215-220, there’s no telling how hot the steam pockets in the head are
. We’ll see what the feelers and straight edge say pretty quick.
I suppose, if it’s low on coolant and the temp gauge is sayin +\- 215-220, there’s no telling how hot the steam pockets in the head are
. We’ll see what the feelers and straight edge say pretty quick.
Re: How hot to warp the head?
Check the head for warpage, they warp easy. Better to address it now than have to tear it apart again. A bit unrelated, but my D17A2 has been overheated to the point of boiling the oil, pinging, and stalling 3 times with no head or block warpage. It just blew the head gasket the first 2 times, and the 3rd time completely killed the engine. However, with the exception of the valve stem seals, the head amazingly was 100% fine. I guess I got very lucky.
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my FORD was programmed by a smart man to cut fuel and kill the motor at 242°. i can then restart the car and drive it for 12 seconds using the startup enrichment table. i have hit that 3-4x due to cooling fan issues, all times i restarted the car and floored it so i could coast and cool off. i never warped anything. i would check it since you're taking it apart anyhow, but to answer your question " does anyone know just how hot the engine has to get to run a serious risk of warping the head?" i would say when i exceed 260 is when i would start to worry
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Talking water temperatures not head temperatures.
If your coolant system is full of air your gauge is not telling you how hot the heads are getting.
Big difference in a full coolant system that’s overheating vs empty cylinder head.
Don’t do this but imagine a coke can full of soda put on a hot stove after a few seconds there will be almost no temperature change as the water has very high thermal mass. Now put that same can on the stove empty and it will heat up almost instantly.
If your coolant system is full of air your gauge is not telling you how hot the heads are getting.
Big difference in a full coolant system that’s overheating vs empty cylinder head.
Don’t do this but imagine a coke can full of soda put on a hot stove after a few seconds there will be almost no temperature change as the water has very high thermal mass. Now put that same can on the stove empty and it will heat up almost instantly.
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The head needed .006" shaved. Not too bad for 240,xxxx miles and having the hi leaking since last summer, almost 20k mi. ago.
All back together and better now.
BTW Slumpter, that' an excellent analogy. Most people don' understand how much energy water can absorb, or the difference between the temp of water in a head vs. A pocket of steam.
Thanks guys
All back together and better now.
BTW Slumpter, that' an excellent analogy. Most people don' understand how much energy water can absorb, or the difference between the temp of water in a head vs. A pocket of steam.
Thanks guys
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