jpmountainboy

So Im just getting my 3.0 back on the road after a long block reman installed.
it overheated the first time. so I put another new thermostat in there(one with little bleeder hole to let air bubbles out. I also replaced the two temp sensors as one was bad (erratic electric timing advance). and replaced the alternator (which was also brand new bosch) because it was charging at 17.2 volts...when I reved the enigne, the temp gauge would go hot to hotter (this is after the new sensors)...anyways so replaced it and now the gauge doesnt do that anymore but it seems to show its warm rather quick, and now fluctuates from hotter than normal, to right below overheat.

the fan clutch is not new, but they are $$$ for the real aisin ones...like $200.

how can I tell the fan clutch is bad??? does anyone want to sell me one???

any ideas on what this could be??? I know I can test the sensors, and might try tomorrow, but they are brand new!! But I guess I had two bad brand new alternators so it could happen. seems fine now though...so I dont think it was a short that caused the bad alternators.

I dont have a shroud as it broke (would buy one of those too), but that didnt seem to be a problem before I changed the engine.

any idears?

PS. I know about the ford fan mod...but just not ready to do that yet...Ive been working on this beast for 2 months now and really just want to stop spending money and wrenching in my freezing cold carport. My girlfriend officially hates my toyota now as it takes all my time.

stagger_lee

You can tell the fan clutch is bad by turning the fan by hand with the engine off of course. You should have/feel a significant amount of resistance upon turning it by hand. If little to no resistance, fan clutch is bad. I would definitely go find a shroud from a junkyard. Did you flush radiator or test it? They go bad, get clogged up too. Did you burp the cooling system properly?

jpmountainboy

ya so the radiator is under a year old, but it did sit out dry for a month, I was thinking about that and if it rusted a little inside during that time. I filled the engine from the top, started/warmed it/ topped it off then let it cool for the night and did that again...even squeezed the bottom tube to burp it. I also have the thermo with the little burp hole too.

the fan has a little bit of resistance, it seems the same as when I got it, however, now that the hood is off when im driving i can see the fan slow down a bit after its warm...its strongest when its cold, which seems backwards, but Im not sure if it always been that way because I never drove with my hood off, but I do know that it would quiet down after it got warm so I think it has always done this.

new water pump too.

Im going to test the new sensor tomorrow, as I have a suspicion thats what it is. It seems like the gauge read it was at a normal operating temp way before I am normally used to it saying so when waiting for it to warm. i just figured that it was a new gauge so it was reading better.

stagger_lee

You should get a good amount of resistance. Why not just grab a Napa or other fan clutch. I could almost guarantee with a good radiator, fan shroud, solid clutch, and an airless system, you will run cool. Find a laser thermo temp gauge and point it at the top hose. Usually most pep boys, shops will have one. Ask them to point it at your top hose real quick, and bring em a 40oz for their troubles. Check water temp there. That will tell you if sensors are f-in with you.

Just passing on proper burping technique. I just did this. But start with the front end lifted up or parked on an decent incline. If all possible getting that lower hose even with the water pump. Top it off and start her cold with the radiator cap off and let her burp herself. Keep the heater on/open as well to get the water flowing through the heater core.

If your gauge fluxuates, thats typical of air in the system. I didn't have so much a problem burping because I didn't run a thermo. Apparently from what I read a thermostat can trap a pocket of air (correct me if Im wrong, GURUs). Being in So cAl, thermos not soo important. I just let her warm up a while longer.