ECT spikes while towing
Posting Guru
Joined: Dec 2016
Posts: 1,284
Likes: 2
From: Bozeman MT
There are a lot of reported failures on the Mishimoto Thermostat having to do with the thermostat not sealing completely. The common advice is to boil the thermostat so that it resets itself and can seal properly - otherwise it is essentially stuck open and the motor will never reach good temperatures.
Postmaster
Joined: Aug 2015
Posts: 3,910
Likes: 18
From: NW IA
Keep in mind with a t stat that keeps the temps lower, your PCM is likely seeing that as too low and throwing extra fuel at things to warm it up, add to that you are throwing colder air into an engine in lower temps--taking away heat from the cylinders, heads, etc.
It's great if you are running a gas engine, since it's a denser and colder charge. With a diesel you want that extra heat, hence some guys going to the 200* t stat.
I noticed this bigly when I was taking flying lesson years ago. Over the winter months when it was around 0*, you could point the plane into the wind, go WOT and it would practically take off in it's own footprint(figuratively speaking)......when it was 60 or above took a LOT more runway to get off the pavement. Gas engines are that way, diesels sort of opposite.
It's great if you are running a gas engine, since it's a denser and colder charge. With a diesel you want that extra heat, hence some guys going to the 200* t stat.
I noticed this bigly when I was taking flying lesson years ago. Over the winter months when it was around 0*, you could point the plane into the wind, go WOT and it would practically take off in it's own footprint(figuratively speaking)......when it was 60 or above took a LOT more runway to get off the pavement. Gas engines are that way, diesels sort of opposite.
Tuned
Joined: Oct 2015
Posts: 392
Likes: 86
From: Roebuck, SC
I put in a 195 deg thermostat from Advance auto, at least that's what it said on the box. In the hot September we had, it was running about 200/204. In this cool weather we've had lately it'll go to 192/194 tops. That's with no load.
I just changed out the oil cooler and radiator in Sept.
I just changed out the oil cooler and radiator in Sept.
Thread Starter
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Freshman User
Joined: Jan 2017
Posts: 28
Likes: 0
From: Florence, South Carolina
1) Go back to stock thermostat
2) remove the tunes
3) in the tech folder is a procedure for doing a coolant system flush. Part of that procedure references an access port on the oil valve body that can be used to back flush the oil cooler. Use a WHITE pipe cleaner and stick it down inside that access port and move it around - IF the pipe cleaner comes out with orange goo/slime on it then you have a situation called "silicant drop out", research it. One solution is Restore.
2) remove the tunes
3) in the tech folder is a procedure for doing a coolant system flush. Part of that procedure references an access port on the oil valve body that can be used to back flush the oil cooler. Use a WHITE pipe cleaner and stick it down inside that access port and move it around - IF the pipe cleaner comes out with orange goo/slime on it then you have a situation called "silicant drop out", research it. One solution is Restore.
Postmaster
Joined: Aug 2015
Posts: 3,910
Likes: 18
From: NW IA
A clogged cooler will not make things spike and drop.
Senior User
Joined: May 2016
Posts: 107
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x2!
If the oil temps are recovering at a decent rate after getting warm, then you might surmise that the cooler is at least performing okay even if partially clogged. I would think twice about running Restore+ through your truck before you've tried the new tstat as mentioned. You might end up with an unwanted result of an extra dose of debris for your oil cooler.
Not sure if there is similar concern with Restore, but probably not as it appears to dissolve/dissociate silicate particulates rather than just dislodge them.
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Freshman User
Joined: Jan 2017
Posts: 28
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From: Florence, South Carolina
Posting Guru
Joined: Mar 2014
Posts: 1,468
Likes: 5
From: Salt Lake City, utah
Did you change the thermostat housing when you did the thermostat. My housing was worn to one side and would stick open/closed every now and again. However my temps never got quite that high.
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Thread Starter
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Freshman User
Joined: Jan 2017
Posts: 28
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From: Florence, South Carolina
yeah the new Tstat came with new housing.. i wont see that high of temps untill all day towing. That was on the way home, loaded after 8 hours of towing and about 3 pukes. so like i said before i know i had to be a little on the low side for coolant. iv been had the heads sent for magniflux and decked all by a rep machine shop OEM gaskets and arp studs.. Im hoping its not HG, just dropped $2200 on Transmisson rebuild from TC exploding..
Postmaster
Joined: Aug 2015
Posts: 3,910
Likes: 18
From: NW IA
yeah the new Tstat came with new housing.. i wont see that high of temps untill all day towing. That was on the way home, loaded after 8 hours of towing and about 3 pukes. so like i said before i know i had to be a little on the low side for coolant. iv been had the heads sent for magniflux and decked all by a rep machine shop OEM gaskets and arp studs.. Im hoping its not HG, just dropped $2200 on Transmisson rebuild from TC exploding..