New head gasket, now truck overheats

Thanks for the backup keakar!!

 

The jiggler is located directly between the two 'arms' that make up the frame of the thermostat. Rotating the thermostat 180° will result in the same orientation of the arms, just with the jiggler at the bottom. So again it wouldn't make a difference to the orientation of the other parts of the thermostat.

 

All i can say is toyota didnt call for it to be that way because they were feeling frisky that day....do a little searching instead of trying to tell us we are wrong...

 

The 6 o'clock/10 deg thing on the 3.4 has been documented countless times then countless more times via SG readings on this and other forums for years. It makes no sense but it's a fact.
The valve on an OEM 3.4 stat is around 10 degrees from one of the "arms" but the orientation of the arms still stays the same with a 180 deg change.

 

Maybe the sake was very good that day.

Im not arguing what is printed in the FSM, I know what the FSM says regarding the valve, im saying i dont believe its going to cause your engine coolant temp to rise 10°. There would have to be some other variable causing this. If mine was a 3.4, i would still install it with the jiggler on top. So lets agree to disagree.

In any case, this is not going to cause a total overheat like the OP is facing. So lets move on.

 

Even after dirty pool s post youd still put it in upside down?

 

I scanned through the FSM shortly after i bought my truck. I revisited that page soon after your first post in this thread. Yes, I would install it with the jiggler at the upper most position. May a lightning bolt strike me if this is going to make any difference in the operation in the cooling system.

 

Well said..

 

I agree with you that it seems silly, but 10 degrees is a significant amount...that would raise your temp guage needle significantly... with the needle at the bottomof the guage to the mid point at normal operating temp is only like 15 degrees. So another 10 would jump that puppy right up there.

Edit** well that might not be right, id have to watch the temp rise to confirm but once the needle starts to move off the bottom it dosent take much to make it rise...

 

Maybe we should set up a bounty on Kickstarter or something. Find someone in LA with a 5vz engine, buy two identical OEM thermostats, hook up my Snap On OBD scanner (faster reporting than the Torque app and those bluetooth deals), and do a back to back comparison.

If theres more than a 5° difference after 15min warmed up, ill do something horrible, like put Hello Kitty decals all over my truck, or drink a Bud Light.

 

make sure you post pictures

my home grown mechanical skills say the jiggler is for bleeding air only and shouldn't ever (and I think couldn't ever) have any effect on temperatures or thermostat operation or engine cooling, but that said, if the FSM says its supposed to be 6 o'clock (on bottom) and they must have "some" reason for saying that.

if I ever change mine the jiggler will go up simply because that's what logic and physics of trapped air in a sealed water system dictate it should be, especially since these engines have a reputation for trapping air which I feel is maybe in part due to the jiggler mounted on the bottom not letting the air bleed out as it should. but I will watch the temps very carefully after installing the stat "incorrectly, according to the FSM.

so to wrap it up, I agree the "said" correct position is 6 o'clock (on bottom) and what I "think" it should be is 12 o'clock (on top)

 

Since the tstat us on the bottom hose not the top like most rigs i dont really see how much air would be trapped in that area anyhow...right?? Seems the air would either go up to the top of the engine or stay in the radiator...

Edit--well i guess thats not correct, if you did a full drain of the rad then filled there would be an air pocket there since the tstat is abouve the bottom port of the rad....

Sorry for thread jack OP!!!

 

Would not matter, trapped air rises to the highest point as long as there is gravity.

Poor @Elow007 is going to be heading to the Ford dealership after this thread.

 

You mean wouldnt matter which hose the tstat is on, inlet or outlet??

 

If i start discussing that, its going to take away from the rest of my plans for tonight, and i was about to go out for chicken and soju.

 

I got it from a diff forum that the thermostat being upside down might cause the problem, but I'm not sure why they suggested that. Now I know.

Before I go on I should clarify. The head gasket was replaced in 2010, due to my job and finances I had to let the truck sit for 4 yrs! I recently got the truck back and the first thing I did was change the coolant, oil, battery and gas. I also poured a little oil in the cylinders to soften up any rust and let it soak for a week. After that it fired right up. Sorry for not including this info in the op. So my coolant change probably caused the overheating in my driveway (cause I didn't do it right). However , when the headgasket was replaced my shade tree mechanic told me that the truck was overheating on the highway.

Today I had some time to work with the truck and have some new information. With the truck parked facing uphill on a slight incline I ran the engine with the rad cap off and heater on. As the engine warmed the coolant level at the rad swelled and I saw bubbles coming out. The heater was blowing hot air. Eventually the engine got too hot and I had excessive coolant loss. So I let the engine cool and repeated the process twice more but this time avoiding getting the engine too hot and loosing coolant as well as introducing more air to the system. The third time I ran the engine with the heater on and the rad cap off the temp stabilized about half way up the gauge (pre-repair level). When the coolant started to swell out of the radiator I capped it and then the truck started to overheat. The whole process of warming and cooling probably took about a half hour.

So I saw some improvement doing this (burping?) but once I put the rad cap on it starts to overheat again. I want to pick up a spill proof funnel and try again, before messing with the thermostat.

I drained the coolant at the radiator and the engine block (per the manual). But I didn't run the heater when I refilled, I just ran till hot and then topped it off the next day.

I think it's obvious at this point I'm no mechanic, and I should pay more attention to the manual and not rely on what I've learned from buddies. That's why I'm here asking this question. I'm also very greatful for the responses. I am sure I've left something out here and I'll follow up on this the best I can.

Thanks again.

 

I've seen this issue many times form aftermarket shops/shade tree mechanics. It is very easy to swap the head gaskets of one side to the other. The most common mistake is that people working from the front of the engine mistake what the real right and left of the engine is. When you swap the gaskets all the holes line up but one hole, that hole is a main passage to the drivers side cylinder. With that hole blocked it will be all but impossible to remove all air pockets and the flow will be very restricted throughout the engine. The gaskets, if factory should be marked with what side they belong to and be able to be read while installed.

Drivers side is left and passenger right.

This same issue plagues people with the 3vz also, another head gasket that will seal up when installed backwards.

 

That was a simple honest question dick... it required a yes or no, was just trying to confirm what you meant...

 

Engine sitting for 4 years... yea that may change things.

 

Fine, i have never bothered to look or care what direction the coolant flows in relation to the thermostat. I assume that its from the lower hose into the water pump, with the thermostat on the outlet. Its like this on 99% of the cooling systems out there. I believe (dont quote me) that some LT1s on Impalas and C5 Corvettes have the thermostat on the inlet side.


Whats correct (i dont care)? Depends on how its engineered (yes, i stand by my 12 o'clock jiggler position). Whats the pros and cons of each design? Not something im going to spend the rest of my Columbus Day off discussing (again, i dont care).


Also, as i just came back from dinner and am a couple sojus deep, im going to pretend youre not an ahole and didnt call me a dick for not responding the way you wanted me to.