nm4runner

quick question. i replaced my radiator and waterpump in june and everything was fine. i was in the southwest so a/c ran all the time. fast forward and add move to east coast (delaware) truck tonight starts to overheat. i come home and check oil/ water... needed about 1/2 gallon of water to fill radiator and quart of oil to make everything fine. could low oil/ low water be the problem. also i havent added any coolant since i did the radiator/waterpump. could some evaporate over time. i did drive the truck out east with the a/c on the whole time. doesnt look like its leaking also no water in oil. thanks in advance

ChickenLover

Did you replace the thermostat as well? A 1/2 gallon short has never made me overheat.

enthalpy

Hate to tell ya - I am going through the exact same thing. The oil was low, so I topped it off. The coolant was a little low when I changed the water pump and timing belt, but I just didn't really worry about it. Last week the temp gauge was flirting with the red and I managed to pull over before it got too high. Drove the truck home later that night with the heater on and the temp gauge was fine (should note that the coolant level was fine)!

Took it to the mechanic the next day - temp gauge was fine. The thermostat was replaced (he wanted to replace that first incase it was something simple). I didn't drive it much over the weekend - but today it was hurting in a bad way. It's getting a lot of white smoke outta the tailpipe and runs pretty rough. The smoke smells acrid and I think that means burning coolant - which is not good. Needless to say this means I get to visit the mechanic tomorrow in the AM and I am pretty sure it's not going to be good news



I dunno - I say check the thermostat for sure as a cheap first step - but keep a close eye on the coolant level...

jimbo74

coolant wont evaporate over time, however if none was ever added since the replacement its possible a bubble in the system cuased it to be low.... as for oil... hmmmmm does your truck burn oil or you dont know?

normally both low coolant/and oil means one is contaminating the other and usually means a blown head gasket, which isnt fun nor cheap to fix..... hopefully thats not the case

nm4runner

just wanted to add a couple of things. its a 95 with 140k miles 3.0 of course. the oil doesnt bother me that much since it is about time for an oil change and i do burn some oil over time. i checked the fan this morning and the clutch seems to be good still. it wasnt smoking that i saw and it was cold outside. the temp went down as i drove just when i came to idleing for a while. ill have to check again later it was dark by the time i looked at it...looks to be some oil/ gunk buildup by the lower hose that connects to the block...wonder if my tstat took a crapper...any other ideas..thanks for the previous msgs...

PirateFins

I'd say change the T-stat first. Could also be air in the system. Check it out

ekim121

Yea, thermostat first, but it sounds like you're burning coolant. If you're burning it slowly then there won't be all that much smoke, but it will overheat because just as water is getting into the cylinder, exhuast gases are getting into the cooling system and creating air pockets that are messing everything up even though it's relatively close to the correct level. For your sake I hope it's just a thermostat...I've never worked in a 3.0, but it seems as though it'd be a pain in the butt to change a head gasket. Then there's also the problem of figuring out which cylinder is burning it so you don't have to pull both sides. Anyways...good luck.

Rick F.

Ummmm... Can you say "head gasket recall"?

nm4runner

i think i found the problem let me know if it sounds plausible...i was able to look at the engine today in the light and noticed a small puddle on the ground. i traced it up to the bottom radiator hose..i noticed that the hose was lower than it should have been and the hose clamp was not very tight. is it possilbe that it would leak out of that. the hose was about a quarter of an inch away from the flange thing that it should be next to. i havent seen a leak since ill keep checking..now i have to go buy some toyota red to put in and drain some of the water i put in it..its cold on the east coast and my poor truck is used to the southwest...

enthalpy

FYI my 4runner is a 94 with 138K - the head gasket was covered under the recall and performed at 78K miles. Of course, my mechanic has my car in pieces and the block/heads got machined today. It's supposed to get put back together tomorrow. Good news is that he went over the valves since he had everything apart. The price was steep ($1200) - but still better than car payments.

Good to hear that it might simply be a loose hose, my problem never gave outward leaks of coolant - so that's a definite plus!

KevyWevy

when my thermostat went out, it was leaking from the lower hose, i thought mine was loose as well. i noticed the leak before it every started to overheat. the water pump had already been replaced, so i just went ahead and changed the t-state for like $25 myself. it fixed the problem.

i agree with some of the other guys that said there was probably an air bubble in the coolant system, thats probably the reason for the low coolant. if i were you, i'd just change the t-stat or have somebody change it for you, but its more fun and cheaper to do it yourself. i did mine by myself, and by no means to i have any experience working on engines.
as for the oil, do you change every 3,000 miles? my 4runner burns about 1 quart every 5,000 miles, i use synthetic.