ATTN Cooling guros - Rig running warm at HWY speeds (1 Viewer)

[FloridaFJ80]

So for those that have followed my build thread. I rebuilt my FZJ engine, and I put all new cooling components:
All new OEM coolant lines, new OEM Water pump, New OEM thermostat, New OEM 3 core Radiator, New OEM Fan Clutch also filled up with Toyota RED.

So here is my issue. At highway speeds the temp starts climbing on a recent trip back from Tampa, the rig climbed up to 220*. but when I am idling at a light or somewhere temps go down fairly quickly back under 200* but at HWY speeds it just continues to climb. I dont have any leaks that I can think off. I burped my coolant system for over 30 minutes. Using this product as seen on a few youtube videos.

http://www.amazon.com/gp/product/B00A6AS6LY/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1

I did not put the front of the truck on any jack stands to burp the system. I also had clogged cats and some exhaust leaks at the y-pipe and manifolds. So this week I replaced the y-pipes with the magnaflow ypipe and cat.

http://www.amazon.com/gp/product/B004SH8CR4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

So now I have a free flowing system, replaced both cats and left the OEM catback exhaust. On a recent 20 mile trip, engine temps monitored via my ultragauge, would climb over 200 within the first 3-4 miles on the hwy and then reached a top operating temp of 208*. I did see a jump a few times from 208 to 204 to 208. But the temp would not go below 200 unless I am parked idling. Outside temp was 85* and I am going 65 mph.

Any ideas..

I have an ARB bumper with 2 Lightforce 240's upfront.

On my LX450, I had the same ARB bumper with lightforce 240's up front and never had any cooling issue always running 194* on the ultragauge. Only once it went over 200* and it was because I had a bypass hose leak. Again I am not seeing any coolant loss anywhere.

 

[NLXTACY]

On the other end of the scale...

 

[NLXTACY]

What is the temperature difference between the upper and lower hoses? Is the coolant staying in the radiator too long? Thus staying in the block too long? Did you test your thermostat to be sure it opened how it was supposed to? There have been reported defective thermostats. A large temperature differential could also point to a clogged radiator.

 

[FloridaFJ80]

Great questions. I haven't dove into any troubleshooting other than burping the system. Wasnt aware of faulty thermostats. How could I test functionality?

 

[NLXTACY]

Great questions. I haven't dove into any troubleshooting other than burping the system. Wasnt aware of faulty thermostats. How could I test functionality?

Unfortunately it means pulling it out and putting it into a bot of slowly heated water to view the opening and the opening temp range. Is the jiggle valve at 12 o'clock?

 

[scottryana]

Off topic seeing your scan gauge is set to ignition advance @NLXTACY could you make a mental note of what your ignition advance is at idle when the truck is at around 110-150 degrees FWT and let me know.

Thanks!

 

[FloridaFJ80]

Yes the thermostat is at 12 o'clock. Is their a technique to open the thermostat or get it to to open quickly while on the truck

 

[NLXTACY]

Yes the thermostat is at 12 o'clock. Is their a technique to open the thermostat or get it to to open quickly while on the truck

You mean while its on the truck and in the housing? How would you know? MAAAAAYBE checking the hardness of the hose at cold vs at operating temperature. At cold there would be water block by the thermostat and at open it should be free flowing. BUT this won't tell if its happening at the correct temp or if its happening in stages or if its opening completely.

 

[NLXTACY]

Off topic seeing your scan gauge is set to ignition advance @NLXTACY could you make a mental note of what your ignition advance is at idle when the truck is at around 110-150 degrees FWT and let me know.

Will do.

 

[Chester]

Take off the lights and pull the horns off, see if there's a difference.

 

[CruiseOrlando]

I found an interesting "phenomenon" when riding up to GSMTR in another 80.

While driving thru Atlanta, his temps started climbing - to the point that the A/C cut off. I was asking a bunch of questions, but nothing made any sense for this particular issue.

So I had him back off of the guy we were following - we were kinda close because we were trying to keep people from getting between us thru Atlanta.

As he backed off, the temps dropped. I think there was some kind of wind vortex going on. I also think his fan clutch needs work - and that might be your issue as well Frank. His temps were just fine at idle, but not so much while moving. His fan didn't have much resistance to it either. And I know "not much resistance" is subjective, but if you feel a fan from an 80 that's in good working order and then try yours, you'll probably notice the difference immediately.

 

[landtank]

stock blue hub clutches are junk as far as I'm concerned. When the engine temps are over 200*, pull over shut off the truck and feel the resistance of the fan clutch. I'll guess there is very little.

 

[FloridaFJ80]

I still have the old fan clutch i will put that on and go for Drive before i start removing the thermostat

 

[1973Guppie]

first bet like rick said would be fan clutch, those lights can't help either for sure, I would look into an led alternative, from my experience things on the bumper really drive air away from the front of the car. Eventually I plan to remove my bumper light bar and go with a curved roof rack mounted one.....

 

[FloridaFJ80]

I can understand the lights but i had the exact same setup on my lx and never had any issues with temps.

 

[bloc]

Transmission could be putting more heat into the coolant in this rig vs the older one. Just because one rig did something you can't assume the other will too.

I agree.. try ditching the lights, even if temporary.. if for nothing other than a data point. If it still runs hot without lights, you can be confident something else is going on. Even if the lights were an issue, a very well operating fan and clutch should keep things cool. Your mileage would take a hit from the HP loss to the fan on the freeway, but it'd stay cool.

 

[FloridaFJ80]

If i have a faulty fan clutch or thermostat why at idle does the temps go down?? What differs other than rpms causing the engine to cool. I am just thinking out loud or its probably to late and i should go to bed. But the cooling system is working to a point because it eventually does cool the engine. From what I understand the fan clutch draws air into the engine cooling the coolant via the radiator. The thermostat opens and closes to allow cooler coolant to enter the engine and the water pump pumps the system . So at idle it operates normally and during normal city driving but during hwy temps climb.

I will remove the lights and go for a drive on the hwy to test. I think that even if they do keep the temps lower than with them on there is still another culprit.

 

[NLXTACY]

Temperature differential between upper and lower hoses?

 

[FloridaFJ80]

Excuse my ignorance but how do i measure that

 

[SmokingRocks]

by feel. Or a cheap infrared temp gun.

Is your fan shroud intact?