Over Heating
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Date: Thu, 26 Sep 96 09:15:00 PDT
From: barney@flowpoint.com (Barney McNamara)
Subject: Truck Overheating
To: TLCAL@tlca.org
I'm looking for help on a minor problem that bothers me when I drive my
'83 pickup on the highway for more than a hour or so. It starts to overheat
when there is anything more than empty bed, flat road, and cool air temps.
The engine is stock (rebuilt) 22R, the cooling system is tight and all new.
The truck has 31" tires and stock diffs, so it revs low. It has 2" extension
shackles, and 3" body lift. The radiator is lowered back in front of the fan,
and all the air deflectors are in place. It seems to develop an air bubble in
the pump, or somewhere that blocks flow. If I stop for just a short while, the
temp goes back down to normal, then climbs again after another hour or so. I
think it may have something to do with the body lift, as the hoses to the
heater core are a couple inches above the top of the radiator. I have a "T"
fitting in the top hose with a screw cap that I can open to release air. The
only air left in the system is that trapped under the cap when I screw it back
on. This problem was with the truck before I installed the rebuilt engine, and
it is still there now.
Any ideas?
Thanks - Barney
------------------------------
Date: Thu, 26 Sep 1996 12:51:24 +0000
From: "Mike Graham"
Subject: Truck Overheating
To: TLCAL@tlca.org
> on. This problem was with the truck before I installed the rebuilt engine,
> and it is still there now.
>
> Any ideas?
Does the temperature drop if you turn the heater on with the fan on
full blast (you'll want to keep the windows open for this test. 8-)
If so, then your problem isn't likely a bubble, it's insufficient
coolant flow. Was the water pump replaced when the engine was
rebuilt? How about the thermostat? There might be two different
thermostat ratings available for your truck (summer, and winter).
You might be running the winter thermo (higher temperature so the
heater works better) year 'round, which could be contributing to the
problem. Lastly, it might be that your fluid coupling is shot. When
you're booting along the highway and the temperature is getting
uncomfortable (not dangerous, just hotter than you think it should
be) then pull over, shut off the engine (this is why you don't want
it too hot; don't want to warp the manifolds) and try to turn the rad
fan by hand (don't touch anything hot in there!). If it spins
freely, the coupling is probably shot.
//////////////////////////////////////////////////////////////////////////
// Mike Graham
//////////////////////////////////////////////////////////////////////////
// 1981 BJ42 24V Diesel LandCruiser, "New brakes, new problems."
//
// "Smell? What smell?"
//
//////////////////////////////////////////////////////////////////////////
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Date: 26 Sep 96 11:18:37 PDT
From: Norman.Goetz@directory.Reed.EDU (Norman Goetz)
Subject: Truck Overheating
To: TLCAL@tlca.org
I just had a lot of work done after gasket failure from overheating. The fix
was just a reverse radiator flush for me, and that might fix your suspected
air bubble too, if that's actually the problem. The thermostat also got
replaced. They don't last forever. They may continue to open but at too high a
temperature, or not wide enough. Another possibility is clogged radiator
tubes.
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Date: Sat, 28 Sep 1996 17:37:47 -0800
From: jbarron@uvic.ca (John Barron)
Subject: ?Bad engine fan clutch?
To: TLCAL@tlca.org
Alfonso;
The viscous coupled fan on Toyota pick-ups and LCs will often change its
sound as it engages and disengages. It will go from a gentle "whirrring"
sound to a really loud "roar." Often the loud roar of the fan is noticeable
for a few moments just after the engine has been started and then it
quietens down considerably. This is *normal*.
The fan on my LC almost never engages and so I don't often hear the roaring
noise BUT the fan on my GF's pick-up (2L-T) does engage willingly and roars
like crazy when the engine is running a little hotter than normal (ie:
towing monstrous trailers up mountains in the summer)...the sound is always
associated with a very prompt drop in the operating temperature of the
engine down to the low side of normal--at which point the noise subsides.
You can check the fan clutch operation by spinning [by hand] the fan when
the engine is cold [and OFF]: it should spin about 1/3 to 1/2 a turn or so
and then stop. There should be a bit of resistance to the movement. If the
engine has just been run and is [a little] warm the fan will spin quite
freely--this is okay. If the engine is really *screaming hot* AND there has
been good flow of air over the radiator then the fan clutch *may* be
engaged and should provide a decent amount of resistance to spinning.
There are no really definitive tests for this procedure AFAIK.
If your fan doesn't ever engage [no roar] and your engine runs hot you may
have either: a defective fan clutch OR a blocked radiator OR a defective
thermostat OR a combination of these three problems. The fan clutch needs
hot air flow over the rad to engage...
To check rad performance [in your back yard] you can drive until your
vehicle has reached normal operating temperature and then mist the rad with
water. If all the water evaporates then the rad is probably alright [as in
not blocked]. If there are areas where the water evaporates and others
where it doesn't [cold spots, usually vertical sections of the rad] then
the rad needs to be serviced [power flushed or rodded-out]. You can also
check for cold spots by using your hand but there is often not a lot of
space between the grille and the rad --> and you could burn your hand. Be
careful.
A rad shop can remove your radiator and check the flow for you if you think
that it's blocked.
A sticking/dead thermostat will also cause the engine temperature to be
higher than normal --this is another issue-- but it will also prevent the
fan clutch from doing its job as very little hot coolant will be entering
the radiator and no hot air will be passing over the fan....Your interior
heater will be really hot [when temp set on high] and your rad cool-ish if
this is the situation...replace the thermostat with a new one that is right
for the climate where you live.
Lastly: if the fan clutch is screwed you may be able to see the silicon
fluid leaking from the clutch housing...then again, maybe not. A very few
clutch fans I have seen are permanently engaged [jammed inside, bad bearing
etc...]. In any of these situations you need to replace it. See your local
Auto-Wrecker, Auto Parts store or Toyota parts person.
- --------------------------
And in the "Oh man, that's a bummer..." department:
I have seen one clutch fan on a Ford Ranger [Isuzu diesel engine] where the
bearing disintegrated and the fan chewed-out the rad...about 10 kms from
the nearest paved road and late at night. The poor guy was on a first date
[going to a lake] with a youg lady whom he had met a few days earlier...she
was *not* impressed at having to walk-out in the dark. (My buddy, Wayne,
and I found them and went back and field-repaired the truck so that he
didn't have to leave it for the midnight thieves).
j.
______________________
Return-Path:
From: Scott Muir
To: "'barney@flowpoint.com'" ,
'TLCAL'
Subject: Truck Overheating
Date: Fri, 27 Sep 1996 11:19:09 -0700
I'd like to know when you first noticed this?? Is it likely the result of
the rebuild? Is there some kind of event that you can link it to? (changing
the tires maybe???)
I would first assume that the thermostat is wonky (even if it is new)
although I can't account for your air bubble. I did have an experience where
suddenly (actually I think it was because of a highway trip towing a boat)
I started sitting at the start of the red on the temp gauge. If I remember
correctly, I had the dealer replace the 'stat and they did, but claimed the
old one seemed to be operating properly. The problem went away. (I was
annoyed because I hate not knowing "fer-shur")
I've never tried this, but the motoring shows suggest getting a cooking
thermometer and cooking your thermostat on the stove in a pot of water to
test its properties.
I recently flushed out my cooling system (I'm no pro but I did the best I
could) in order to put in new prestone. I took out the engine drain plug
and it was bone dry. Using a piece of coat hanger I stabbed it in there
and managed to disturb the sediment enough to get some flow. Eventually
I got a really good rate of outflow. There was a lot of sediment down there. I'm sure if the engine was
rebuilt this would have been cleaned up at that time, but who knows?
Lastly, I would suggest maybe the temp sender is wrong?
As Mike suggested, try using the cab heater to see what effect it has.
I remember that my heater during the boat trip was working REALLY REALLY
WELL. It was noticably hotter then what it was at normal operating temp.
I doubt this is possible, but could the engine be plumbed wrong??
_______________
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Date: Tue, 1 Apr 97 08:32:29 PST
From: barney@flowpoint.com (Barney McNamara)
Subject: damn! I always put ".com" instead of ".org"!
To: Toy4x4@tlca.org
On Mon, 31 Mar 1997 PSHENG@SCUACC.SCU.EDU wrote:
> decide it wants to run hotter now? I don't think the gauge is faulty,
> 'cuz when it was near the red, I turned on the heater and I was
> afraid it was going to melt my dash! Any ideas? thermostat maybe?
My '83 has heated up since I got it. Every time I drive steady for a couple
hours on the freeway, and everyday when I go over Hiway 17, a 15 minute climb
of 2000 feet over about 5 miles in traffic, the things heats up and the needle
climbs into the red. It seems to cool quickly, if I stop for gas on the
freeway, it drops again a stays down for another few hours.
So far I have changed: radiator, water pump, fan belt, engine, heater core,
water hoses, temperature sender, dash gauge, fan clutch and thermostat twice.
The first thermostat was a 190 degree job that really gave me a lot of heat
but it just ran too close to the top all the time, the second is a 160 degree which
gives a little more room for the eventual climb.
I've decided that the thing is just keeping me on my toes. I always keep a
close eye on the gauge. It has never overheated, never belched steam (at
least since the head gasket blew on the old engine.) It doesn't lose any fluid,
it moves in and out of the overflow tank as it heats and cools. I think it
has something to do with the body lift causing excessive wind resistance
or screwing with the water flow. I've got a "T" fitting in the highest
point in the heater hose where I can bleed air. When it's hot I can crack
the screw-on lid and it spurts fluid, so I'm pretty sure there is no air in
the system.
I just live with it.
______________________________________________________________
Barney McNamara 83 Toyota Short Bed
( barney@flowpoint.com ) stock 22R motor ; 3" body lift
Santa Cruz, Ca. 8" alloy rims; 31" BFG A/Ts
______________________________________________________________
------------------------------
Date: Tue, 1 Apr 1997 16:47:06 -0500 (EST)
From: Ironmenn@aol.com
Subject: damn! I always put ".com" instead of ".org"!
To: Toy4x4@tlca.org
In a message dated 97-04-01 11:29:31 EST, you write:
<< Subj: damn! I always put ".com" instead of ".org"!
Date: 97-04-01 11:29:31 EST
From: barney@flowpoint.com (Barney McNamara)
Sender: Toy4x4-request@tlca.org
Reply-to: Toy4x4@tlca.org
To: Toy4x4@tlca.org
I think it
has something to do with the body lift causing excessive wind resistance
or screwing with the water flow. I've got a "T" fitting in the highest
point in the heater hose where I can bleed air. When it's hot I can crack
the screw-on lid and it spurts fluid, so I'm pretty sure there is no air in
the system.
I just live with it.
______________________________________________________________
Barney McNamara 83 Toyota Short Bed
( barney@flowpoint.com ) stock 22R motor ; 3" body lift
Santa Cruz, Ca. 8" alloy rims; 31" BFG A/Ts
______________________________________________________________
Hey Barney
Just a thought, did the radiator get moved back down to its origanal height
when the body lift was installed? If it didn't moving it down should make a
big difference.
John
------------------------------
Date: Tue, 1 Apr 1997 19:22:49 -0500 (EST)
From: DRM033@aol.com
Subject: damn! I always put ".com" instead of ".org"!
To: Toy4x4@tlca.org
In a message dated 97-04-01 11:29:31 EST, Barney writes:
> I've decided that the thing is just keeping me on my toes. I always keep a
> close eye on the gauge. It has never overheated, never belched steam (at
> least since the head gasket blew on the old engine.) It doesn't lose any
> fluid,
> it moves in and out of the overflow tank as it heats and cools. I think it
> has something to do with the body lift
I would say the body lift is your problem. As someone posted recently, the
location of the fan in respect to the radiator is VERY important. If you did
not lower the radiator, that could be it. Also, cutting the shroud could
cause the fan not to be able to do its job. replacing all those parts will
do nothing if the fan is not in a position to do the work.
David
DRM033@aol.com
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Date: Wed, 02 Apr 97 09:29:37
From: "Fisher, Gary"
Subject: overheatin'
To: toy4x4@tlca.org
> I have a strange problem w/ my '85 4runner (22RE, 135K miles, bone
stock)-
> my temp. gauge usually stays in the bottom 1/4 of the dial, but will
> venture farther up if I take a long drive on the freeway or the
weather
> all week. The weather here's been pretty warm, but not super hot-
> there's plenty of fresh coolant (changed less than 10K miles ago),
> overflow tank is full, no leaks, oil is fine... why would my truck
I had the same problem. It turned out being that my radiator fins were
full of mud. I took the radiator out. Hosed it down until I could see
through it again and now all is fine. Before I hosed it, I could only
see through about 10%!!
Gary Fisher
********************************************************
* garyf@hpa.com.au *
* '89 Toyota Hilux Extra cab 2.8 turbo diesel *
* 32' BFG, ARB bars all round *
********************************************************
------------------------------
Date: Tue, 1 Apr 1997 11:53:51 -0500 (EST)
From: SKeene8194@aol.com
Subject: overheating 22re
To: Toy4x4@tlca.org
In a message dated 97-03-31 18:42:47 EST, you write:
<< PSHENG@SCUACC.SCU.EDU wrote:
> I have a strange problem w/ my '85 4runner (22RE, 135K miles, bone
stock)-
> my temp. gauge usually stays in the bottom 1/4 of the dial, but will
> venture farther up if I take a long drive on the freeway or the weather
> is really hot. The other day I noticed that the needle goes at least
> halfway up during normal driving, adn I drove down to big sur last
> weekend, and it was running just below the red zone. What would cause
> the water temp to go up all of a sudden like that? It's been like that
> all week. The weather here's been pretty warm, but not super hot-
> there's plenty of fresh coolant (changed less than 10K miles ago),
> overflow tank is full, no leaks, oil is fine... why would my truck
> decide it wants to run hotter now? I don't think the gauge is faulty,
> 'cuz when it was near the red, I turned on the heater and I was
> afraid it was going to melt my dash! Any ideas? thermostat maybe?
Yes, its likely the thermostat. On the 22RE, it takes maybe 5 minutes and
$5 to replace - I'd try that before anything else. Fan clutch would be the
next place to look given what you've said.
--
-- ej@blarg.net >>
When the head gasket blew on my 81 22R I replaced the thermostat as a
precaution. My radiator also had a big crack in it so that was replaced to.
Before all this my guage always ran at the bottom 1/4 of the guage no matter
what the driving conditions. After I got it running again I ended up with
the same problem you described. Over a year I tried replacing the thermostat
again with a better brand name. Then I went and bought the genuine Toyota
thermostat. Then the fan clutch. Nothing made any difference. I then went
back to the radiator shop and accused them of selling me an inferior radiator.
He said that he had 2 Toyotas himself and that the stock recommended
thermostat of 95 Deg. is too high. He gave me Stant brand 80 Deg.
Thermostat to put in which I did. Problem solved. The truck now runs
at the lower 1/4 of the temp. gauge again.
Since my radiator was new you will have to get yours checked out. It may
need to be roded out. Also, the radiator shop told my never to use stop
leak. It is made to stop water from flowing through small holes. Since the
radiator is made up of small flat tubes then these tubes will become clogged
by the stop leak as well. The powdered type can cause you to lose 10 or 20 %
of your cooling capacity right off the bat.
Stop leak should be the tool of last resort to get you back to civilization.
Then flush it out of the cooling system compleatly, and get the real leak
fixed properly.
Steve Keene
skeene8194@aol.com
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Date: Tue, 01 Apr 1997 21:15:16 -0700
From: Tony Bartlett
Subject: overheating 22re
To: toy4x4@tlca.org
Replace your thermostat. In my opionion stock t-stats suck. My
brothers went bad and warped his head. Mine went bad but luckly I
noticed the signes because of my brothers problems.
If you are driving and you notice the gauge going hot, then out of
nowhere it goes back to normal. Then it might be the t-stat. My guage
started going hot about once a month then got worse about once a week.
by the time a would pull over it would be back to normal. It was the
t-stat.
If you have the problem at low rpm and not highway it might be the fan
clutch. Please by Toyota, the price has dropped alot and I have gone
threw 3 fan clutches from checkers(last two under parts warranty) before
I spent the money for a Toyota clutch. Just put it in but my original
lasted 180,000 miles.
------------------------------
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Date: Wed, 2 Apr 1997 21:03:24 -0800 (PST)
From: barneym@scruznet.com (Barney McNamara)
Subject: 83 overheating
To: Toy4x4@tlca.org
Eric wrote:
>Have you replaced your radiator cap? If its releasing too early, that
>could be a problem.
I have not recently changed the cap, but if it was releasing, won't I loose
water and see steam?
>Have you pressure tested the system?
No, wouldn't a pressure failure cause coolant loss?
>Do you still have a fan shroud? That could be part of your problem.
Yes, fan shroud is where it should be, it is lowered back down around
the fan, in front of the engine.
John wrote:
>Just a thought, did the radiator get moved back down to its origanal height
>when the body lift was installed?
Yes, The radiator is down in front of the fan and engine.
David wrote:
>I would say the body lift is your problem. As someone posted recently, the
>location of the fan in respect to the radiator is VERY important. If you did
>not lower the radiator, that could be it. Also, cutting the shroud could
>cause the fan not to be able to do its job. replacing all those parts will
>do nothing if the fan is not in a position to do the work.
Yes, the radiator and shroud (not cut) are both where they belong.
Nick wrote and suggested an electric fan to replace the mechanical one.
Also several other letters discuss sticking thermostat issues. I can see
when my thermostat opens, the temperature climbs up to a point, then
stops, which I assume is where water flow starts. When I got the truck,
it had no thermostat (and the fan shroud was in the bed), and it never
warmed up at all. When I replaced the heater core and valve, I got no
heat due to lack of engine heating up. After adding the first thermostat,
I still had no heat. I found that my friend, the previous owner :-(
had used so much anti-leak gunk that the pipe under the intake manifold
which feeds the hose to the heater was completely blocked with the stuff.
I had to pull off the pipe and clear it out with a coat hanger to get any
water to flow to the heater core. I've got plenty of heat now, in fact,
a little too much. I also had a time when it really overheated after I'd
gotten stuck in a muddy puddle. The mud had filled in the bottom 1/4 of
the radiator fins, and was blocking all air flow. (Now that I remember
that episode, I'm wondering if maybe some of that mud is still in there,
still blocking air flow?)
I appreciate all the feedback. I think I'll try the radiator cap - that
seems cheap. I'll check on the pressure test, and also try feeling for
hot/cold spots on the radiator. I also have an electric fan I could try
hanging in front of the radiator for more air flow at low speed.
I'll let you all know what I find.
______________________________________________________________
Barney McNamara 83 Toyota Short Bed
( barney@flowpoint.com ) stock 22R motor ; 3" body lift
Santa Cruz, Ca. 8" alloy rims; 31" BFG A/Ts
______________________________________________________________
----------------------------
------------------------------
Date: Tue, 01 Apr 1997 22:57:02 -0600
From: Steven Benson
Subject: Overheating 22re
To: toy4x4@tlca.org
Didn't see the original thread to this one but one thing to keep a close
eye on with 22re's from past experience had been the timing. I've seen
similar problems in the past with members of my club who have advanced
the timing for performance reasons or simply setting the advance by ear
due to faulty electronic advance disconnect. Chances are it's something
else entirely but it's worth a check to see.
______________________________________________
Steven Benson
'85 Toy X-Cab | MNTOYX4 | MN4WDA | TLCA #4835
http://www.off-road.com/~MNTOYX4
mailto:toyx4@winternet.com
----------------
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