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Pretty sure I explained well enough for most people.
 

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Discussion Starter #103
How? Difference? Yes. Obvious? Obviously not! Brapp would have figured this out long ago.

Cooling System Diagram in first post.
Updated Coolant Line Diagram (changed for many mods) - NASIOC

Oil Cooler is in a bypass in in the passenger side loop. But it's not the only path or the primary path. The only thing the thermostat controls is radiator flow. It has nothing to do with this.




Coolant changes little if at all from getting hot or even boiling.

We have symptoms - and a logical diagnosis. Shouldn't have taken us this long! :(
Removal and replacement of oil cooler results in hot oil. Oil cooler not working should have been the primary suspect right off the bat.
It's an interesting thought. I don't know enough about that system to comment, so it's definitely seeming like a good thing to investigate.

I tested the sensor tonight. Took boiling water, transferred it to a metal can, and within 1 minute had the sensor in it. The elevation at my house is 7700 ft and according to online sources, it seems like water should boil at about 196 degrees here. The submersed sensor read 190 degrees. I have to imagine the water lost a degree or two due to the thin metal can it was in as well. So to me that seems like a working sensor.
 

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Discussion Starter #104
How? Difference? Yes. Obvious? Obviously not! Brapp would have figured this out long ago.

Cooling System Diagram in first post.
Updated Coolant Line Diagram (changed for many mods) - NASIOC

Oil Cooler is in a bypass in in the passenger side loop. But it's not the only path or the primary path. The only thing the thermostat controls is radiator flow. It has nothing to do with this.




Coolant changes little if at all from getting hot or even boiling.

We have symptoms - and a logical diagnosis. Shouldn't have taken us this long! :(
Removal and replacement of oil cooler results in hot oil. Oil cooler not working should have been the primary suspect right off the bat.
I don't know enough about the system to say one way or another... but it's an interesting thought. Would you think the cooler itself would be the issue or one of the hoses/connections going to it?

I tested the sensor tonight. Took boiling water, put it in an aluminum can, and within 90 seconds or so had the sensor in it and was reading off the gauge in the car. According to online sources, water at this elevation (7700 ft) boils at about 196 degrees. The sensor read the water temperature at 190 degrees. I'd also assume the can absorbed a small amount of heat. So it seems like the sensor is accurate within about 5 degrees.
 

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Discussion Starter #106 (Edited)
So it seems right now that the only thoughts remaining from anyone (on here or otherwise) is the tune or the oil cooler.

I've reached out to my tuner to get his thoughts. Considering going for an aftermarket oil cooler kit that would replace the stock one. If that is the issue, it'll solve it as well. If not, it should at least let me keep things cool.
 

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Unless something got into the cooler, it's the plumbing which is just a couple hoses.

When external coolers are installed in is normal to keep the stock one too? Then you need to fix it anyway, and it's not going to be difficult or very expensive.
 

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Discussion Starter #108
Unless something got into the cooler, it's the plumbing which is just a couple hoses.

When external coolers are installed in is normal to keep the stock one too? Then you need to fix it anyway, and it's not going to be difficult or very expensive.
It still seems like if the hoses were blocked then the coolant system would be acting odd and getting hot as well. In fact the cooling system is working super well as even with 260 degree oil temps, water temps stayed normal.

But, good point about easy to swap. Probably worth just trying it.

And even if it isn't the hoses, I wonder if the cooler could have a blockage or have gotten less efficient somehow.

I believe when installing external oil coolers, it is normal to delete the stock one. And in my case, it would definitely be necessary as the extra height from the sandwich plate would otherwise push the oil filter into the headers.

One thought I got from a friend at autocross today was that perhaps the oil pump is struggling and is not pushing oil through the system as efficiently as it should. Thus leading to the oil getting hot.
 

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It still seems like if the hoses were blocked then the coolant system would be acting odd and getting hot as well. In fact the cooling system is working super well as even with 260 degree oil temps, water temps stayed normal.
NO!!! It's in a bypass dedicated to the cooler and only the cooler. You couod removed the cooler and block it off. I posted a link showing the routing. Once you realize it's in a bypass, and consider the size of the cooler. That bypass can not do cooling significant enough to affect the overall system. The plumbing is simply to small.


And even if it isn't the hoses, I wonder if the cooler could have a blockage or have gotten less efficient somehow.

Yes, I'd be concerned about that. look in the ends. Blow it out with compressed air - in both directions.


One thought I got from a friend at autocross today was that perhaps the oil pump is struggling and is not pushing oil through the system as efficiently as it should. Thus leading to the oil getting hot.

OK. That is a plausible explanation - no wait - wouldn't that cause low oil pressure?

But from a previous post:

Removal and replacement of oil cooler results in hot oil. Oil cooler not working should have been the primary suspect right off the bat.
 

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Discussion Starter #110
NO!!! It's in a bypass dedicated to the cooler and only the cooler. You couod removed the cooler and block it off. I posted a link showing the routing. Once you realize it's in a bypass, and consider the size of the cooler. That bypass can not do cooling significant enough to affect the overall system. The plumbing is simply to small.
Hmm. I think I see what you mean. The diagram to me looked like the cooler was in the same route as the passenger side heads. But I'm not too good with reading diagrams for such things.

What do you think could actually be causing the restriction? I'm trying to think of what could cause a hose to not pass sufficient fluid without leaking or anything.


mheyman said:
OK. That is a plausible explanation - no wait - wouldn't that cause low oil pressure?
I would imagine it would. I don't have an oil pressure gauge so I can't be certain. Perhaps the pressure is low but not enough to cause other immediate issues so it is only being noticed by the high temps.
 

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What do you think could actually be causing the restriction? . . .I'm trying to think of what could cause a hose to not pass sufficient fluid without leaking or anything.
Could just be a bend sharp enough to partially collapse a hose. They are formed, and at least on of them has a 90 in it


I would imagine it would. I don't have an oil pressure gauge so I can't be certain. Perhaps the pressure is low but not enough to cause other immediate issues so it is only being noticed by the high temps.
I don't think oil pressure is the issue - but if I did I'd be saying don't rive it till you are sure it is good.

You know the old saying "don't fix it if it aint broke". It comes from real experiences. I'm not saying not to do maintenance or mod, but when you do work on something and it stops working you should know where to look.
 

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Discussion Starter #112
Could just be a bend sharp enough to partially collapse a hose. They are formed, and at least on of them has a 90 in it
Great. I'll take a look at those.

mheyman said:
I don't think oil pressure is the issue - but if I did I'd be saying don't rive it till you are sure it is good.

You know the old saying "don't fix it if it aint broke". It comes from real experiences. I'm not saying not to do maintenance or mod, but when you do work on something and it stops working you should know where to look.
Totally. That's why my mind went to the headers, as they were the only thing that got worked on.

This wouldn't be the first time though that I put on a new part and something else happened to go wrong at the same time. Perhaps from the car sitting in the air without being run for a longer stretch, perhaps something else got bumped during the install, or perhaps the new part ended up putting extra strain on something that was already stressed enough.
 

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Totally. That's why my mind went to the headers, as they were the only thing that got worked on.
Perhaps you blown up my guess, but I took:

I do not have an external cooler, just the stock oil/coolant heat exchanger. From the research I've done... it doesn't seem like those really go bad. It did have a very slow oil weep at the seal, but I replaced that and it had no noticeable effect on the temps.
to mean you had worked on or with your oil cooler - which was my whole point. If not that makes it far less likely it the problem. Rereading I believe that the oil temps were already hot before you messed with it.

Other than that... the only things that changed around the same time were adding an AOS,
Water cooled AOS? If plumbed as in the diagram it should have made no difference.
 

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Discussion Starter #114
Perhaps you blown up my guess, but I took:



to mean you had worked on or with your oil cooler - which was my whole point. If not that makes it far less likely it the problem. Rereading I believe that the oil temps were already hot before you messed with it.



Water cooled AOS? If plumbed as in the diagram it should have made no difference.
Oil cooler was never touched. Oil temps were normal in the past.

Regardless, I think it's a good thought. One that has been shared by others among my racing friends.

Yes, water cooled AOS. I believe all was installed correctly... and I think if it was done wrongly it would have been pretty obvious from the start. But worth a thought.

I'm working 8am to 1am ish every day this week and hoping to run SCCA Time Trials this weekend at High Plains Raceway. Had a couple friends come through for me... picked up a spare stock oil cooler as well as a complete oil cooler setup with a 25 row Mocal cooler. Dropped it all off tonight at a good shop -- hopefully they can either find an issue with the stock cooler/lines and/or install the Mocal setup so I can still run this weekend.
 

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Discussion Starter #115
Well... after way more headaches and heartaches... still basically where I was before.

Due to poor work done by a shop that installed the cooler, I didn't get to drive the car more than 1 practice session at the TT event. When I did, in a cool morning session temps stabilized at around 255. Which is okay, but still seems high.

I was forced to redo the cooler -- now... running a Mishimoto 25 row cooler in the lower grill opening (about half exposed to full airflow) and I'm still seeing temps of slightly over 220 around town, rising to 230 pretty fast if I start giving it boost. This seems to be the case even when it's not particularly hot out... I hit 220 the other day driving on the highway in the rain.

I've done one autocross since having the cooler in. I'd go out for a run with temps about 210 and return with them about 220 which quickly rose to 230-240 when sitting in grid. Spraying water on the cooler got them back down to 210 again for the next run.

I'm pretty much completely out of thoughts at this point -- I was planning to run Gridlife at the end of this month but I can't imagine how the temps could stay cool enough when they don't even stay below 220 driving around town.

It's starting to seem to me like something is really wrong internally with the motor. It seems that most folks have trouble even getting the oil up to temp running a cooler of this size... and it seems to be fighting to keep up for me. I have been wondering how many others might have had an issue like this and just ended up spinning a bearing because they didn't know the temps got too hot. In any case... I just want my car back and it's starting to seem like tearing the engine down is becoming my only choice...
 

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Mishy thermal products are not known for being the most efficient out there. I'm not surprised by the somewhat marginal improvement. I would recommend a Mocal setup.


Also, just out of curiosity, have you had an oil analysis done?
 

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Discussion Starter #118
Mishy thermal products are not known for being the most efficient out there. I'm not surprised by the somewhat marginal improvement. I would recommend a Mocal setup.


Also, just out of curiosity, have you had an oil analysis done?
Funny enough, the 1st cooler was a Mocal 25 row cooler. Temps seemed similar to the Mishimoto. Unfortunately due to a shop's poor choices on the install that cooler is now fairly worthless.

Still... a 25 row cooler, even if not very efficient, seems like it shouldn't be fighting to keep up with a stock turbo, stock motor car...

I actually just took an oil sample to send to Blackstone earlier tonight.
 

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Discussion Starter #119
If you need a good core, I'd look towards the Fluidyne Therm-HX models. They are really effective, even at low airflow.
Appreciate the recommendation.

Question for you... as a tuner, can you see any possible way that the tune could be causing the high temps?

Basically 3 things changed and the car almost immediately started having high oil temp issues.
1) Stock header to Killer B
2) SPT intake to Grimmspeed intake
3) Tune

Coincidences happen... but it just seems strange. I feel like I've ruled out radiant heat from the header, the intake should be providing cooler air than before... so that leaves the tune.
 
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