Overheating has got me!

Alright guys and gals, I'm having some overheating issues with my 97 taco 2.7 4x4. I bought this truck as a project in December 2014 and have almost got it to perfect but I'm overheating again.

This is what has been done to it recently (not all necessesairly to do with cooling system):
* thermostat (twice)

* Flushed cooling system before the second therm

*triple checked all hoses and clamps

*flushed overflow

*new fuel injectors
*cleaned throttle body

*new air filter

*new power steering pump

*new acv

*new plugs and wires

*oil change and filter

Any ideas? Its killing me! I'm new to the tacomas and I have only had 22r's/re's. Decided to upgrade my playtoy to a truck with ac!

Any ideas or long shots will be greatly appreciated!

Thank you all in advance,

Dustin

 

Possible head gasket leak or bad water pump. Are you losing coolant? If so maybe headgasket. If you can rev it to bring temp down maybe water pump.

 

I was really hoping it wouldn't get to that. Im losing a little coolant, but when I changed the oil last I couldn't detect any coolant in the spent oil. That's what gave me a small amount of hope for the head gasket.

 

I just took it for a test run because I have driven it in about 2 weeks now. It kinda seems like it's a circulation problem to me. It start going from half to hot until you hit about 3000rpms (I know the air is cooking it off some but it's doing it in all gears not solely at high speeds). It is a drastic drop at 3000 rpms it will immediately drop from hot to below half. Idk I could just be in denial.

 

Overheating again...? What was wrong the first time? - might be a hint to what's wrong this time. Do you have stuff like lights, or other accessories mounted in front of the grill blocking the radiator?

If I'm not mistaken, you can have a head gasket leak without the oil being contaminated. The coolant could be leaking directly into the cylinder and converted to steam during combustion. If it's bad I think the exhaust will be white colored. Might be able to see a puff of white come out of the exhaust first thing in the morning after it's been sitting all night. Just have someone else start it for you while you watch.

I once had a car that blew a radiator hose and I lost all my coolant in about a minute. After I fixed all the hoses and tried refilling it, the system was air locked so the full capacity of coolant wouldn't go into the block, leading me to think it was full. The temperature rose pretty fast after I started it (~5min or so) and I realized what happened. I ended up repeatedly squeezing the radiator hoses to get the coolant moving. Seems like the radiator flush could have lead to the system being empty during that process, possibly causing air lock.

Good luck.

 

You know, I never thought of airlock. Brilliant! It wouldn't take a full jug of coolant when I filled it up after flushing. Just didn't think much about it. I will take a look at it once it cools down a touch lol.
I should also add I put 33s on it after I got running good with the new parts. I haven't tourtered it off-road yet, wanted to make sure everything was still holding up well before I did.

But when I first got it, it was bad. It's a one owner truck, but the one owner was the absolute worst vehicle owner imaginable. It had cracked headers, exhaust holes, needed fuel injectors, overheating, and a few more things. But the interior was probably the worst. I had to end pressure washing the entire inside with seats and all just to be able to get in it without vomiting.

 

Sounds like air in the system.

 

I appreciate yall. I'll probably wait for a little daylight. I'm here in nc so we ain't got too much longer to wait but I'll keep yall posted.

 

Have you washed out the fins on the radiator? Actually taken the radiator out and sprayed the the fins with water? That is one of the first things I did when I got my truck. All kindss of crap came out. Grass seeds,mud, little stones.

 

Check the radiator for possible cracks and the heater core. Do you smell coolant inside the cab or in the engine bay after running the truck?

 

Check the fan clutch also.