3.4 overheating

I have a 1985 4Runner with a freshly re built 3.4 installed.
New water pump installed with re build.
New Champion 3 core radiator (fits the 85 mounts)
New clutch fan
New fan
Toyota factory t-stat.
runs great and cool down hill.(I have installed aftermarket digital gauge and it shows as low as 150 down hill on hot days) Factory gauge rides in the middle at this time
Uphill, it gets hot 206-221. Sustained uphills will see 220-230 especially at lower rpm and at 55 or greater.
Installed a .9 cap and got boil over. installed a 1.1 cap and no boil over but still raising temps.
I have had the hydrocarbon test performed and none.
Installed a modified fan shroud to allow the larger fan blades of the 99 motor with the space of the 85.
Also a note, I tried drilling extra holes in the t stat in case of air bubbles.
I have burped the system on an incline with heater on as well.
Anything Im missing?
Seems to get hot at freeway speeds on flat ground as well at lower rpm's.
H
E
L
P

 

The OEM thermostat for the 3.4L has to be installed with the jiggle valve at the 6 o'clock position, contrary to the common position of 12 o'clock for the bubbler. It's been tested and shown to run 10+ degrees hotter when installed incorrectly. Do you know if your thermostat is correctly installed?

 

It is installed in the 6 position plus 3 extra holes drilled at this time

 

You’ve been pretty thorough in your effort but you didn’t mention if the T stat is verified not in backwards. Your symptoms are similar to that. It would open enough when no stress like downhill but wouldn’t get enough flow to cool when uphill. You could even try running without a T stat to eliminate that issue.

 

Spring towards block

 

Did it run cool/normal before the rebuild? I see it's a swap into an 85? Is the engine positioned properly to the shroud/radiator for maximum efficiency?

 

Not sure of condition of motor other than it had just shy of 200k
Fan sits inside of shroud and looks to be in the correct position

 

Have you ever seen it run without getting hot?
I'm trying to figure out where we're starting here, that's all. You've provided great details by the way, definitely helps the internet troubleshooting to have as much info/details as possible

 

Cool, need all the help I can get. Ran warm ever since I’ve gotten it back from the build. Runs good in the winter.
I also have a Warn power plant winch in front of the grill??
There is also a power steering cooler that was mounted directly to the radiator but now is moved 2” toward the front of grill mounted with brackets.
Do you think the 3 core radiator is dropping coolant to fast?

 

Cool thanks for the extra lil bit of info.
The engine resides on the frame/in the engine bay as it did before the rebuild?
So you're positive all the air is out of the system? Have you actually seen/put eyes and ran with the radiator cap off to see the coolant circulate and see that has good strong flow?
Accessories or other things positioned in front of the radiator like the winch can definitely affect air flow

 

It seems to flow good
I should see a good stream flowing through the top when the t stay opens, correct?

 

Yep.
Touched the lower radiator hose to make sure the radiator is actually cooling the coolant properly? Is the coolant getting too hot in the block for some issue/defect or is the radiator not transferring enough heat out of the coolant for some reason?

 

I’m not sure if this helps, but in the winter, the rig runs often at 140-150°

 

It never warms up? Like running without a thermostat?

 

Yup
That’s what it seems like

 

T-stat is verified to be working? It's not sticking closed or open? 140-150 seems super cold for a 3.4 to run even in winter.

 

I will replace tomorrow
This time, no added holes

 

Oh shit yeah that's right, I forgot about the thermostat mod. Yeah that's why it doesn't warm up in winter

 

Anything to do with the overheating you think?

 

Yeah that's what kinda gave me a bit of pause from responding right right away, I was typing and I had think that out and reword it as to not imply it could be the cause of the overheating as well. Just because I don't know. You would think it wouldn't, right? But man I also wouldn't have thought the jiggle valve would go in at 6 o'clock. Know what I mean?