Coolant Temperature - random spike (1 Viewer)
- Thread starter Cruiserhead05
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- Thread starter
- #22
Got it! Although we won’t know definitively that this is the issue, it appears I have a hefty coolant valley leak. There is quite a bit of built of pink crust so my assumption is that its been going for some time and I’ve lost enough coolant that the temps can no longer stay controlled. Will likely incorporate a few other obvious coolant system updates while we’re in there but I think we can assume this is the primary culprit. Thanks @bloc for the tips on which foam to pull.
bloc
SILVER Star
Damn. Yeah, this is a bigger issue than the radiators. Less common, way less likely to be spotted, and slow enough that people often don’t see anything on the ground or even smell anything.
Still, with those high temps get your coolant tested, or maybe send off an oil sample for analysis. They’ll catch coolant in the oil far earlier than you’d see sludge under the cap. IF you need a head gasket and it’s at that early of a stage you can often get by without any work to the block or head beyond a good cleaning.
Still, with those high temps get your coolant tested, or maybe send off an oil sample for analysis. They’ll catch coolant in the oil far earlier than you’d see sludge under the cap. IF you need a head gasket and it’s at that early of a stage you can often get by without any work to the block or head beyond a good cleaning.
Interesting thread, came across it because I have been wondering if my temp gauge movement is normal. My specific concern I’m noticing is that upon acceleration, my temp gauge needle swings to the halfway or slightly past halfway mark. Typically it sits at 1/4 of the way towards the low range, but when I have normal acceleration, the needs swings higher, but then swings back down the moment I let off the gas. Is this normal? Thanks.
Sounds like you’re looking at the oil pressure gauge....
haha! What a newb I am. Blaming it in new father sleep deprivation! 
thanks
- Thread starter
- #27
So I’m going to check fluid levels again this AM to see if it takes any more fluid and drive it some more to see if temps continue to remain happy.
Assuming they do, and given the leak has clearly been small enough to go unnoticed, wondering if it’s safe to drive the next few days until I can get it in for repair. Doubt anyone is going to feel comfortable suggesting that, just thinking out loud.
Assuming they do, and given the leak has clearly been small enough to go unnoticed, wondering if it’s safe to drive the next few days until I can get it in for repair. Doubt anyone is going to feel comfortable suggesting that, just thinking out loud.
bloc
SILVER Star
Actually since you seem to have identified both the cause of the temp swings and the cause of the low coolant (and it’s a slow leak) I’d feel fine driving it, but I’d be paying close attention and keeping the coolant full. If it starts rough or smokes white after start, potential HG issue.. so in a way driving it is good to help identify other problems.
These engines are tough and as long as everything runs normally until you get the leak fixed, you’re good to go.
- Thread starter
- #30
Agreed. If not for the AC that stopped blowing cold the other day, truthfully I wouldn’t even know this was happening. Truck runs totally normal. There’s almost a hidden danger in how much abuse some of these motors can take.
Now that I’m aware of it and have an scanner connected I’ll be watching it like a hawk to avoid any long term damage.
Now that I’m aware of it and have an scanner connected I’ll be watching it like a hawk to avoid any long term damage.
At the risk of being the outlier here, and looking at your first posting, I think there is something else going on. The valley leak is messy but ultimately it is relevant only in that it reduces coolant available. "Rowing" through gears to 55 mph is not a serious heat strain on this motor. Down two quarts does not lead to a pegged temp gauge though I have never had that happen actually. So I think there is something else going on. I would drive it, monitor it closely, and expect to find something else. A collapsing hose would be my first guess. Good luck. It would be great if I am wrong.
If you have a known leak in your cooling system and you need to keep driving, then I would top off the radiator when it is cool and leave the cap loose a 1/4 turn open but still locked in place. The cooling system will not build pressure, just expand and contract with temp.
The location of the slow leak is low enough to create a void of cooling fluid that moves from the block to the radiator causing the hi temp spike when you get on the throttle that is connected to the water pump that runs out of fluid then gets fluid back after gravity returns the fluid level back to the pump.
This is the same thing happening when a cracks opens up on top of the radiator except that this leak is within the block.
Remember this method when out on the trail or away from service on any water cooled engine.
The location of the slow leak is low enough to create a void of cooling fluid that moves from the block to the radiator causing the hi temp spike when you get on the throttle that is connected to the water pump that runs out of fluid then gets fluid back after gravity returns the fluid level back to the pump.
This is the same thing happening when a cracks opens up on top of the radiator except that this leak is within the block.
Remember this method when out on the trail or away from service on any water cooled engine.
Good advice from 4gotalot. Coincidentally, a friend brought a vehicle by our place to use a rack to find a coolant leak just last week. It leaked badly. We could not really find it. He loosened the cap, thereby reducing pressure (lowering the boiling point and heat transfer capacity of the coolant) and the leak stopped. Permanent fix. Of course not, but it might get you home without damage.
cc93cruiser
CRUZAHEAD
Dude, just jump on it and fix it.. Not too bad of a job, just takes time and some hard to reach bolts/nuts.. Only the toyota gasket maker is the expensive part.. Here is my thread I started years ago :
Kind of "Mystery" Coolant leak back of engine (heat exchanger valley leak)
Hey guys, I had another thread going on on my 09 Lx puking out coolant from what I thought was the waterpump.. But after taking wheels off and a bunch of other plastic crap off of the front of engine (more than I want to remember) waterpump area is completely dry and is coolant drip free (no...
forum.ih8mud.com
- Thread starter
- #35
I know, i know. It's shameful. Between work, small kids and other responsibilities, wrenching on the cruiser has become a back-burner thing. It doesn't help that @OTRAMM is 15 mins down the road and a reliable source for trusted work. Ryan and his team will be knocking it out next week, along some other components of the cooling system (water pump, t-stat, belt, etc.)Dude, just jump on it and fix it.. Not too bad of a job, just takes time and some hard to reach bolts/nuts.. Only the toyota gasket maker is the expensive part.. Here is my thread I started years ago :
Kind of "Mystery" Coolant leak back of engine (heat exchanger valley leak)
Hey guys, I had another thread going on on my 09 Lx puking out coolant from what I thought was the waterpump.. But after taking wheels off and a bunch of other plastic crap off of the front of engine (more than I want to remember) waterpump area is completely dry and is coolant drip free (no...
As for more data, I've now driven the truck ~90miles/day to and from work with no issues and temps never going over 195*F. Right now, the priority will be for the repair next week, and then an oil analysis as well.
cc93cruiser
CRUZAHEAD
I hear ya bro.. I am just forced to find time and work on my junk because I am too poor to pay someone else to repair my stuff...
32cls6speedmt
SILVER Star
Please do share how many billable hours if you are having this completed by mechanic. Well be a great future reference.
- Thread starter
- #39
I think I read once that the dealership showed 11hours by “the book”.
I’m looking at more like 8 ish I think
I’m looking at more like 8 ish I think
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- Thread starter
- #40
Duplicate post
