Topic: Radiator/Cooling issues

[wslytoy]

Hey guys,
I've got an issue that's driving me crazy. I've got an 85' 4Runner w/ a 3RZ that I swapped in, I can't keep that thing from wanting to run hot. I had an e-fan on it, but it just steadily crept up to warm, and I'd have to shut it down. The engine isn't even broken in yet, it's a newly rebuilt motor, so I'm trying to be super careful w/ it. I've got maybe 200 miles on it. Anyway, I pulled the e-fan off b/c it just wasn't cutting it, I put the stock fan and clutch back on, hoping that would solve the issues. Well, I had to swap the radiator out at the same time b/c I put 1 of those 2 row all aluminum eBay radiators in(it leaked, had to warranty it)... I got everything buttoned up, filled it all back up w/ coolant, now the motor is wanting to run hot after only a couple minutes, and the radiator isn't even getting warm. What gives? I squeezed on the upper and lower radiator hoses(both new), and you could hear the coolant sloshing(technical term) around in the radiator. I'm thinking there must be an air pocket of some sort in the coolant system that's keeping it from flowing. Does that sound legitimate to anyone else? How do you "burp" the system? I've never had to do this before. Any insight would be appreciated! Thanks, Wes

[emsvitil]

remove thermostat and see what happens

[wslytoy [OP]]

remove thermostat and see what happens

I hadn't even thought of that... I'll give that a shot.

[79coyotefrg]

drill a 1/8th inch hole in the thermostat

[kneedownnate]

That's a bandaid glen, he needs to find his real issue first.  If all thermostats needed a 1/8th hole in them, they'd come like that from the factory.

[66cobra]

check the water pump you may have a restriction like a rag or a wasp nest that the rag was supposed to prevent while the motor was sitting around just a thought if the thermostat checks good

[wslytoy [OP]]

check the water pump you may have a restriction like a rag or a wasp nest that the rag was supposed to prevent while the motor was sitting around just a thought if the thermostat checks good

Well, I pretty much had everything sealed up w/in a couple of days when I installed everything. I'm gonna check the thermostat first, if that's not the issue, then I'll start looking at the water pump. I'm just confused as to why the radiator was basically "cold" while the engine was clearly getting hot.

[emsvitil]

You didn't put the thermostat in backwards did ya?

[wslytoy [OP]]

You didn't put the thermostat in backwards did ya?

I'm almost positive I didn't... but,  when you're doing an entire drivetrain swap, there's a lot of room for little mistakes that can drive you crazy trying to figure them out. I'm gonna dive into it tomorrow night, hopefully I'll get it figured out pretty quick.

[Cheesemaker]

Definitely try the t-stat. 
Also check the water pump. 
Park it on a steep hill and get all the air burped.
Another thing is, what type of gauge you using?  Since you got a 3rz swap, did you put in aftermarket gauges, or did you convert things over to get the factory dash to read the info?  I know most guys here really don't trust the factory gauge, and install aftermarket gauge.   
Alot of times the temp gauge will climb higher than normal and then drop down after the t-stat opens.

[emsvitil]

......... I'm just confused as to why the radiator was basically "cold" while the engine was clearly getting hot...........

I think this is the biggest clue....

[Steve_925]

my 2rz runs at 210 give or take 5degree at all times. ive had a 3.0 rad in it now an aluminum, and 2 different e-fans and nothing has changed more than a couple degree. i remember i tryed taking the t-stat out and it would run 180-190 so im thinking of doing that again

[wslytoy [OP]]

my 2rz runs at 210 give or take 5degree at all times. ive had a 3.0 rad in it now an aluminum, and 2 different e-fans and nothing has changed more than a couple degree. i remember i tryed taking the t-stat out and it would run 180-190 so im thinking of doing that again

Well, I pulled the t-stat out tonight, but it's got an o-ring around the t-stat, and it just doesn't seem like a good idea to remove the t-stat leaving the o-ring in there by itself. It doesn't seem very secure. I had the t-stat in there correctly, now that I looked at it again, I remember that it was pretty much idiot proof. With in minutes, like 5, the engine is wanting to run hot, the radiator is cold to the touch, and I still haven't resolved the issues. I was doing better when I was running the electric fan. Only problem is, it would eventually work its way up to hot even w/ the e-fan running all the time. I'm trying to sell the thing, but I can't set it anywhere w/ it in this condition. I'm tired of throwing money at it.

[possume22]

it ur radiator in not getting hot the water is not circulating its has to be the pump or stat radiator my guess is stat is stuck if you wanted to test the stat put it in water boil on the stove in a pot and get it out see if it opens up but i would just buy a knew one there cheap

[herpestes]

sounds like you got air trapped back of t-stat...............as posted earlier drill a 3/16 hole to bleed air out of block.

[possume22]

what will the  3/16 hole do if the stat opens it will not have are trapped you said it crept up to warm how warm you sure your letting it get warm enough to open and circulate on my dodge it gets up 2  230 then the stat opens and  then it cools and stays at 200

[jimbo74]

what radiator are you running in it?