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Boulder Cruiser
08-23-2010, 06:34 PM
97 fzj80 with 168k miles. I have searched and checked the Faq on Mud but can seem to find any answers to my problem.
According to my scanguage II It was running around 190-200 in the city but if i went up an incline at highway speed or in the city It would shoot up, i had to put on the heaters a few times because it would get to 215-220 and keep going if i didn't stop.
I started trying to diagnose, first thing was a new rad cap and it didn't do anything. Flushed the rad (looked fine inside) and temps went down a few degrees but still very hot.
So i went ahead and bought a new Radiator (performance radiator), Thermostat, and fan clutch and did a complete coolant flush with Toyota red.
My temps have gone down alot but im still getting hot up bigger inclines. Its running around 185-193city but going up hills like canyon or lee hill its getting up to 215 and doesn't seem to stop.
I have not done a compression check but i did replace the plugs a week ago and all were dry, also im not having any bubbling in the overflow so i don't think it's the HG.

Im at a loss of what else to do, could the water pump cause these symptoms? Any other suggestions?

wesintl
08-23-2010, 06:41 PM
fan clutch? are you losing any coolant?

Boulder Cruiser
08-23-2010, 06:44 PM
No leaks and replaced the fan clutch.

wesintl
08-23-2010, 06:51 PM
sorry missed that. I don't have a scan guage so I dunno what I hit on the hills. I think 220 is when the stock guage starts to tilt up. that's still Ok. maybe robbie has some idears

treerootCO
08-23-2010, 06:56 PM
Is your exhaust restricted? The cats could be clogged.

coax
08-23-2010, 07:12 PM
What kind of fan clutch did you replace with? Is the mixture of coolant/water where it should be? Anything blocking the "radiator infront of the radiator" like dirt or other 4wheeling debris? Just a few thoughts.

Boulder Cruiser
08-23-2010, 07:21 PM
I have not checked the cats, dont know how??
Blue fan clutch, i believe i did 50/50 for the coolant, maybe a little more water. I sprayed the all the rads to clear debris, i do have PIAA up front and tried taking them off but it makes no difference.

60wag
08-23-2010, 08:22 PM
If the cat is restricted, the manifold vacuum should drop to near zero well before wide open throttle and make the truck noticeably slower than normal.

An issue that could show up on 60s (not sure about 80s) is a collapsing lower rad hose that restricts flow. A new lower hose or adding the internal spring to it solved that issue.

Uncle Ben
08-23-2010, 08:40 PM
Is your exhaust restricted? The cats could be clogged.

:eek: http://www.everydaynodaysoff.com/wp-content/uploads/2010/03/Cat-Suppressor-From-Movie-Postal.jpg :thumb:

nakman
08-23-2010, 09:26 PM
Are you running the AC when it gets hot? does turning the AC off have any effect?

Boulder Cruiser
08-23-2010, 09:43 PM
It does help with the AC off (doesnt heat up as quickly) but it will overheat either way.

Bikeman
08-23-2010, 09:44 PM
When you say the temps keep going up and won't stop, maybe see if they will stop. X2 on the AC.

Romer
08-23-2010, 09:44 PM
Did you replace the fluid in the fan clutch? There is a thread on mud about the Mod. I did not change the temp setting screws, but replaced the fluid with 8,000 CST I bought at a Remote Control model shop. Noticed a big difference. I would use 10,000 CST next time.

Do you have dual batteries, lights or something else in front of the grill to restrict airflow?

You can add an aux fan, I did because I have a packed engine bay with dual batts and an SC

Edit - I see you took off your PIAAs. I use to have to take mine off when towing over the mtn passes before I got my aux fan

Boulder Cruiser
08-23-2010, 09:45 PM
If the cat is restricted, the manifold vacuum should drop to near zero well before wide open throttle and make the truck noticeably slower than normal.

An issue that could show up on 60s (not sure about 80s) is a collapsing lower rad hose that restricts flow. A new lower hose or adding the internal spring to it solved that issue.

I read about the lower rad hose, is there a way to check it or do i just have to replace it?

Romer
08-23-2010, 09:47 PM
also, is your overflow bottle filled to the line with rad fluid?

Boulder Cruiser
08-23-2010, 09:54 PM
When you say the temps keep going up and won't stop, maybe see if they will stop. X2 on the AC.

You mean just keep driving it and see how hot it will get? I'm worried ill blow the HG? I went on a night run to Switzerland two nights ago and i had both heaters on high going up sugerloaf, i got up to 220 before i pulled over and let it cool down.

powderpig
08-23-2010, 09:55 PM
You state that the cooling was better with the new Radiator from Performance, is it the aluminum single row radiator they sell? I would also up grade the Fluid in the Blue fan clutch. Typically the water pump does not fail in the manor that you are thinking about, where it does not push fluid.
As for the lower radiator hose, if the hose is real old and soft, then I think they could suck it close, but for the most part, the hose is short and sturdy. I have not seen any 80 series stuff suck the lower hose to the point of closeing off.
But I do think you have a different issue. How long did you perform the Bubble test and at what RPM?

Romer
08-23-2010, 09:55 PM
How about an air pocket, did you "burp" the system?

Boulder Cruiser
08-23-2010, 10:04 PM
Did you replace the fluid in the fan clutch? There is a thread on mud about the Mod. I did not change the temp setting screws, but replaced the fluid with 8,000 CST I bought at a Remote Control model shop. Noticed a big difference. I would use 10,000 CST next time.

Do you have dual batteries, lights or something else in front of the grill to restrict airflow?

You can add an aux fan, I did because I have a packed engine bay with dual batts and an SC

Edit - I see you took off your PIAAs. I use to have to take mine off when towing over the mtn passes before I got my aux fan

I didnt mess with the fan clutch, i've read about the fluid but figured i wouldn't need it with all this new stuff. Guess ill have to look into it, i can feel it kick in so i know its locking up, it would help if it locked up earlier i suppose. Truck is totally stock, i really didnt see any difference when i took the PIAA's off.

also, is your overflow bottle filled to the line with rad fluid?

Yep its a little less than full (line).

Boulder Cruiser
08-23-2010, 10:10 PM
You state that the cooling was better with the new Radiator from Performance, is it the aluminum single row radiator they sell? I would also up grade the Fluid in the Blue fan clutch. Typically the water pump does not fail in the manor that you are thinking about, where it does not push fluid.
As for the lower radiator hose, if the hose is real old and soft, then I think they could suck it close, but for the most part, the hose is short and sturdy. I have not seen any 80 series stuff suck the lower hose to the point of closeing off.
But I do think you have a different issue. How long did you perform the Bubble test and at what RPM?

Definitely the new radiator helps. Its the only radiator they sell 93-97, it's plastic/Aluminum. I'll go get some fluid for the fan clutch and try filling it up.

As for the bubble test, I got the truck up to temp pulled over, and watched for bubbles i would rev the motor but never saw any. My oil is clean, and so is the coolant.

Boulder Cruiser
08-23-2010, 10:15 PM
How about an air pocket, did you "burp" the system?

I did, but i dont know if i did it right. I had it running with all the heaters on (front tires on jack stands to raise the front), waited for the thermostat to open and filled the radiator as needed. I did this for awhile to make sure there weren't any air pockets.

powderpig
08-23-2010, 10:45 PM
One of the best times to do the bubble test is like pulling Lee hill(it sounds like you may live in that area). When you see the high temps. Pull over(in a safe area), rev the engine to 3-3500 rpms and hold the revs for a few minutes(usually best to have a helper to make it easier). See what you can see.
Anyhow, the other way is to make sure you truck good on coolant, run until the T-stat cycles a few times. Then hold the RPM at 3-3500 for 4-5 min or less if bubbles appear.
It sounds like you burped the system well.
Do you have a stock T-stat in the truck?

corsair23
08-24-2010, 12:29 AM
226F is AC cutoff so that is when I would really start to worry :)

x2 on replacing the oil in the fan clutch (although I have not done that yet myself) vs. just filling it up. Lots of opinions on MUD re: this. Tools R Us seems to have done some pretty extensive testing and has come to the conclusion that the new blue hub fans aren't as good as the old ones with the stock fluid and therefore really need 10K+ CST fluid depending on where you live. IIRC they are running 20K CST + down in AZ.

Your in town temps are pretty close to mine although with the hot weather I've been hitting 200-202. A month + ago I hit 220F heading up I70 in the hot afternoon temps. I've also installed an aux fan but Robbie suggested that straightening the fins on the AC condenser (or is the radiator?) would have helped just as much. If yours are boogered it might be worth the time to buy a radiator comb and straighten them.

Boulder Cruiser
08-24-2010, 10:35 AM
One of the best times to do the bubble test is like pulling Lee hill(it sounds like you may live in that area). When you see the high temps. Pull over(in a safe area), rev the engine to 3-3500 rpms and hold the revs for a few minutes(usually best to have a helper to make it easier). See what you can see.
Anyhow, the other way is to make sure you truck good on coolant, run until the T-stat cycles a few times. Then hold the RPM at 3-3500 for 4-5 min or less if bubbles appear.
It sounds like you burped the system well.
Do you have a stock T-stat in the truck?

Ok i'll go try that today and see if i get any, lee hill has been one of my main test roads. The t-stat is stock, i believe it opens at 185

Boulder Cruiser
08-24-2010, 10:40 AM
226F is AC cutoff so that is when I would really start to worry :)

x2 on replacing the oil in the fan clutch (although I have not done that yet myself) vs. just filling it up. Lots of opinions on MUD re: this. Tools R Us seems to have done some pretty extensive testing and has come to the conclusion that the new blue hub fans aren't as good as the old ones with the stock fluid and therefore really need 10K+ CST fluid depending on where you live. IIRC they are running 20K CST + down in AZ.

Your in town temps are pretty close to mine although with the hot weather I've been hitting 200-202. A month + ago I hit 220F heading up I70 in the hot afternoon temps. I've also installed an aux fan but Robbie suggested that straightening the fins on the AC condenser (or is the radiator?) would have helped just as much. If yours are boogered it might be worth the time to buy a radiator comb and straighten them.

Where do you get fluid for the clutch? Does Toyota sell it? I'll look at the condenser and see, i have power washed it a few times to make sure there wasn't any debris in there.

Hulk
08-24-2010, 10:46 AM
Where do you get fluid for the clutch? Does Toyota sell it? I'll look at the condenser and see, i have power washed it a few times to make sure there wasn't any debris in there.

You can get it from Toyota or from an RC shop. Go in and ask for 10,000 CST silicone oil.

coax
08-24-2010, 11:12 AM
Where do you get fluid for the clutch? Does Toyota sell it? I'll look at the condenser and see, i have power washed it a few times to make sure there wasn't any debris in there.

Make sure if you go to a hobby store you go to hobby TOWN and not hobby LOBBY. I tried hobby lobby first and its the arts, crafts, material store. Hobby Town will have the oil. :\

Boulder Cruiser
08-24-2010, 12:51 PM
One of the best times to do the bubble test is like pulling Lee hill(it sounds like you may live in that area). When you see the high temps. Pull over(in a safe area), rev the engine to 3-3500 rpms and hold the revs for a few minutes(usually best to have a helper to make it easier). See what you can see.
Anyhow, the other way is to make sure you truck good on coolant, run until the T-stat cycles a few times. Then hold the RPM at 3-3500 for 4-5 min or less if bubbles appear.
It sounds like you burped the system well.
Do you have a stock T-stat in the truck?

Just went up lee hill. Got it up to 215F (AC on) and pulled over and had my dad rev it to 3k while i checked the overflow. After a few min of no bubbles i called it good.

Boulder Cruiser
08-24-2010, 12:53 PM
You can get it from Toyota or from an RC shop. Go in and ask for 10,000 CST silicone oil.

Make sure if you go to a hobby store you go to hobby TOWN and not hobby LOBBY. I tried hobby lobby first and its the arts, crafts, material store. Hobby Town will have the oil. :\

Boulder Toyota and Mountain states dont have so ill go check Hobby town. Thanks for the info.

rover67
08-24-2010, 01:47 PM
it's the oil that goes in the little shocks for the RC cars if they look at you funny when you ask.

corsair23
08-24-2010, 02:32 PM
Dealerships I believe will only have the lighter weight oils...Best to just head straight to a hobby store that sells RC cars and parts :)

Uncle Ben
08-24-2010, 05:34 PM
it's the oil that goes in the little shocks for the RC cars if they look at you funny when you ask.

Actually anything over 5000 would be used for diff fluid to create bias (viscous lock up) on an RC.

rover67
08-24-2010, 06:08 PM
Actually anything over 5000 would be used for diff fluid to create bias (viscous lock up) on an RC.

dang.

And here I thought I knew something. :)

Romer
08-24-2010, 09:28 PM
I went to a place that was a remote control hobby shop called RC something. There is one in Highlands ranch and one in Aurora, maybe other locations

TIMZTOY
08-24-2010, 10:34 PM
Transmission fluid ! Whats your temps ? If your towing you might need a larger cooler. Or a secondary cooler. If your fluid is old and dirty you might want to consider changing it out with newer fluid. (Toyota only fluid) its claimed to be a lifetime fluid but if our putting your truck under "extreme" driving conditions . Ie. Towing and offloading, the fluid is no longer "lifetime" towing and offloading creates higher temps for the fluid. Which cause the clutches to slip more causing fluid break down. Which can intern lead to over heating cooling systems. Because the trans fluid is not dissipating the heat fast enough. Or the tranny is creating it to fast !

powderpig
08-25-2010, 07:12 AM
Your 80 does not have the life time tranny fluid, it is good old dexron III. As for your trans cooler, it does go into the raditor first and then to a secondary cooler(like a 20k size one).
You may want to use a infared temp sensor and see what the in and out temps on the radiator may be(you may well be under sized, Perfromance uses what is called a super single these days, it is only one row, big fat tubes, this may not be enough radiator). As well as the running temps on the tranny.
Did you check your engine timing, firing at the wrong times could have a effect on Temps(also may indicate some thing else is wrong).

Air Randy
08-25-2010, 10:14 AM
Dealerships I believe will only have the lighter weight oils...Best to just head straight to a hobby store that sells RC cars and parts :)

It figures that in order to make an 80 work right you have to buy stuff for it from a toy shop :lmao::lmao::lmao:

TIMZTOY
08-25-2010, 10:19 AM
It figures that in order to make an 80 work right you have to buy stuff for it from a toy shop :lmao::lmao::lmao:

Touché :lmao::lmao:

Boulder Cruiser
08-25-2010, 09:30 PM
Went and got the fluid, Im gonna drain the clutch tonight and fill it up in the morning.

I'm not sure what the temps are on the trans since the scanguage wont show it. Ive never seen the light on the dash come on though. The trans fluid looks and smells fine but im no expert. I'll do an oil change in the next couple days.
Thanks for the help guys.

Boulder Cruiser
08-26-2010, 06:34 PM
Ok filled the clutch up and flushed the trans per this thread http://forum.ih8mud.com/80-series-tech/19299-transmission-fluid-exchange-writeup.html.

Its running a lot cooler in town. I drove to Denver today for the first time with the new stuff on but still hit 215F (AC On) going up some hills. I haven't driven it up lee hill yet for comparison. What's too hot? I mean i've been thinking that 215-225 is warrant for stopping and 225-240F is when things start failing. Am i correct with those numbers?

Robbie, I don't know how to check the timing. I agree with you on the radiator, i think its a little small, Unfortunately i don't have the money to buy a Toyota rad. Do you think having the original all metal one re-cored is worth it? Anyone know what that costs? I'm running out of funds pretty quick.
On a positive note my trans shifts alot smoother :cheers:

corsair23
08-26-2010, 06:47 PM
Man you get after stuff :thumb:

226F is AC cutoff when the ECU starts trying to "protect" the truck so IMO that is when I start getting really worried - actually I'm with you that once I get over 210-215F I start watching the temps like a hawk. I'm not sure I've ever seen what Toyota says is the max temp when the engine goes boom...

I just had the radiator in my 80 done and it made a huge difference. But it was flow tested before getting done and it was only flowing at like 25% :eek: - Cost wise it was less than $100. Might be worth a call to find out if someone will flow test it for you first before going that route.

Only other things I can think of are making sure you got the t-stat installed correctly and did you test the fan clutch opening temp? Landtank on MUD says they ALL need to be tested before use because they are coming from the factory set wrong...Tool R Us says the ones he has seen have all been fine so take that all for what it is worth. Tools though is the guy that tested the old fan clutches against the new blue hub version and determined the newer blue hub versions aren't as good and sheer the oil quicker, thus the need for the heavier stuff. He also suggests that if you can get your hands on a known good old fan clutch to go with it. I can't remember if the old ones are "serviceable" or not :confused:

If you have some time...here is an interesting read over on MUD discussing similar issues to yours with lots of suggestions/opinions :)

http://forum.ih8mud.com/80-series-tech/408882-80-series-cooling-issues.html

powderpig
08-29-2010, 08:28 AM
I did not want to take time to re read all this, But how is your A/c condensor, can you see through it? Are the fins straight, and not plugged with dirt, mud etc? (what made me think of this is on the Woman's run, I saw a Ford with the fins all folded over on the condensor , got to know that no air is flowing through that puppy)
Also did you get a chance to take the reading of temps before and after the radiator when it is at it high point temp wise?