Cooling down the 22RE

[centralman]

air dam is the pice below the bumper I riped the one off 1989 toy 4X4 truck and my milage went down and the temp went up

thx ken

Still not sure what it is, do you have a link or photo for illustrative purposes?

Thank you for your advice.

[victorg]

WME, what's your update?

No hydrocarbons. So the head gasket it ok. I've replaced the thermostat and radiator cap, and that helped a little, but no much. I think I'm gonna get a new radiator; it's more expensive to rod it out than to buy a new one. I'll keep you posted.

Victor G.

[centralman]

No hydrocarbons. So the head gasket it ok. I've replaced the thermostat and radiator cap, and that helped a little, but no much. I think I'm gonna get a new radiator; it's more expensive to rod it out than to buy a new one. I'll keep you posted.

Victor G.

What do you think if we use 16psi cap instead of the 13psi one and give it a try?

[Maineah]

What do you think if we use 16psi cap instead of the 13psi one and give it a try?

That maybe pushing it I think I would worry about my 20+ year old heater core.

[85mirage]

i'm not mechanically inclined in any way but had similar issue long time ago. my mechanic put in in different temp thermostat maybe not even for 22re and problem solved.

[centralman]

That maybe pushing it I think I would worry about my 20+ year old heater core.

I understand your concern, I think about that too and I would just do a moderate test on the vehicle see what happens.

i'm not mechanically inclined in any way but had similar issue long time ago. my mechanic put in in different temp thermostat maybe not even for 22re and problem solved.

Did you know what he put in?

[Derek up North]

He might have simply put in a different one, just to make sure it was operating correctly. Just because a new one has been installed does not mean that it is operating correctly. Have you placed the current one in a pot of water to watch to see that it is opening fully before the water reaches a boil? No matter the thermostat rating (160*, 180*, 190*), they should all be fully open by 212*!

[Maineah]

I understand your concern, I think about that too and I would just do a moderate test on the vehicle see what happens.

Did you know what he put in?

If you want to try a higher pressure cap why not loop the heater core hoses. There were two different temp thermostats but I don't think in your case that's a problem because it's opening at operating temperature and if it's running hot it is unlikely that it's closing. I would guess at this point you probably have tried running it with out a thermostat any way. Just an off the wall ideal is the thermostat installed properly? They are off set to one side and I think the by pass port can be blocked open if it's not lined up.

[Gulfstream Greg]

I would guess at this point you probably have tried running it with out a thermostat any way.

If I remember my 22R thermostat, isn't the thermostat a part of the gasket. Mine had a rubber ring around the outside edge of the thermostat itself. This also brings back a memory with that 22r in an 81 pickup. The thermostat failed, it would open but apparently would partially close at high rpm, such as pulling a steep grade. I remember being on the road far away from home and having to tear the inside out of the thermostat when I decided to take it out so I could get home because of that rubber ring around the outside edge.

[Maineah]

Yes they have a kind of "O" ring that fits around the outside edge of the thermostat that is the gasket for the housing. They are off set and it has a round disk that closes the bypass port when it opens I can't remember if it is not where it belongs weather it fouls up closing the bypass if it does it will not get full flow to the radiator.

[centralman]

He might have simply put in a different one, just to make sure it was operating correctly. Just because a new one has been installed does not mean that it is operating correctly. Have you placed the current one in a pot of water to watch to see that it is opening fully before the water reaches a boil? No matter the thermostat rating (160*, 180*, 190*), they should all be fully open by 212*!

Yeah my mechanic friend tested the thermostat before putting in, it was ok.

If you want to try a higher pressure cap why not loop the heater core hoses. There were two different temp thermostats but I don't think in your case that's a problem because it's opening at operating temperature and if it's running hot it is unlikely that it's closing. I would guess at this point you probably have tried running it with out a thermostat any way. Just an off the wall ideal is the thermostat installed properly? They are off set to one side and I think the by pass port can be blocked open if it's not lined up.

The thermostat installed properly, in fact, I have tried 3 different types of thermostat already, and in the end the coolant still spills out from the expansion tank when driving at interstate speed. No, I haven't tried running the truck without a thermostat.

[Maineah]

Yeah my mechanic friend tested the thermostat before putting in, it was ok.

The thermostat installed properly, in fact, I have tried 3 different types of thermostat already, and in the end the coolant still spills out from the expansion tank when driving at interstate speed. No, I haven't tried running the truck without a thermostat.

The only problem with no thermostat is the bypass port will remain open. If you have an old one jamb it open and try it.

[chopinman]

The only problem with no thermostat is the bypass port will remain open. If you have an old one jamb it open and try it.

I solved my problem centralman! It was a tired fan clutch and a partially plugged radiator. I've driven my rig up the mountains in 90+ weather and over 65 mph, and it stays below half, a little obove 1/4. New radiator from Auto zone ($115.00) and new clutch fan ($52.00). I'm ready to hit the road with very little fear.

[centralman]

I solved my problem centralman! It was a tired fan clutch and a partially plugged radiator. I've driven my rig up the mountains in 90+ weather and over 65 mph, and it stays below half, a little obove 1/4. New radiator from Auto zone ($115.00) and new clutch fan ($52.00). I'm ready to hit the road with very little fear.

Good for you! I am not so lucky. I have changed both the fan clutch and a brand new 3 row radiator already, but still the same.

[Gulfstream Greg]

I solved my problem centralman! It was a tired fan clutch and a partially plugged radiator. I've driven my rig up the mountains in 90+ weather and over 65 mph, and it stays below half, a little obove 1/4. New radiator from Auto zone ($115.00) and new clutch fan ($52.00). I'm ready to hit the road with very little fear.

I think the clutches are thermally activated. At least that's what it seemed like with our 22r turbo. After pulling a grade for awhile the fan would ramp up. High engine rpm but slow road speed. I never remember it ramping up at 65 mph though. If it had I would have heard it because it was loud. The noise was actually a bit annoying but I suppose to move that much air any fan would be loud. With the V6 I have not noticed that the fan ramps up, perhaps its quieter. I have not had a overheat problem so maybe the fan clutch is different in the V6.

[motoyhomme]

I travel between Northern Virginia and East Tennessee quite often on I81/I40. Usually I average 65-70 mph on the trip in my 83 Sunrader R22. The temp guage always sits in the 1/3 to 1/2 range. It will go to the 1/2 mark if I run for any length of time around 75 mph. On one trip averaging about 65 mph it rose toward the red, slowing down to 55 brought it back to the 1/2 range.

After arriving home I checked it out and found two things out of the ordinary. Some of the exhaust manifold bolts were loose. Don't know if that had to do anything with the problem or not. But the other thing I did was replace the fan belts. They looked new, but I did install 2 new ones of a higher quality, and tightened them just a smidge tighter than the recommended deflection. I have never had the heating problem again, and didn't have any bearings go out on the alternator or water pump. It seems the fan belt would slip at the higher RPMs but it didn't squeal when first starting up.

Allen

[centralman]

I travel between Northern Virginia and East Tennessee quite often on I81/I40. Usually I average 65-70 mph on the trip in my 83 Sunrader R22. The temp guage always sits in the 1/3 to 1/2 range. It will go to the 1/2 mark if I run for any length of time around 75 mph. On one trip averaging about 65 mph it rose toward the red, slowing down to 55 brought it back to the 1/2 range.

After arriving home I checked it out and found two things out of the ordinary. Some of the exhaust manifold bolts were loose. Don't know if that had to do anything with the problem or not. But the other thing I did was replace the fan belts. They looked new, but I did install 2 new ones of a higher quality, and tightened them just a smidge tighter than the recommended deflection. I have never had the heating problem again, and didn't have any bearings go out on the alternator or water pump. It seems the fan belt would slip at the higher RPMs but it didn't squeal when first starting up.

Allen

Hi Allen, Sorry for the late reply ... I would like to update my progress here.

The belts were replaced by the previous owner a couple of years back, since then it had put on 13,000 miles.

I took the MH to my mechanic to tighten the belts just before going on a trip from Vancouver, BC.

Coolant no longer spills out, but at constant speed around 60-65mph on the interstate, the coolant temp indicator will go up to 3/4 way from Cold to Hot, at lesser speed around 55 mph, the indicator will stay at half.

One thing I find it odd is that the coolant level still drops a bit from top of the radiator the next morning after it cools down. It acts as if it doesn't suck the coolant all the way back in from the expansion tank when the engine cools down, but the rad cap is only a year old and I don't know why this is happening.

And the belts were replaced at a Toyota Dealer. I don't know if they are good enough, and what would be the ones with higher quality in your opinion?

[Maineah]

Hi Allen, Sorry for the late reply ... I would like to update my progress here.

The belts were replaced by the previous owner a couple of years back, since then it had put on 13,000 miles.

I took the MH to my mechanic to tighten the belts just before going on a trip from Vancouver, BC.

Coolant no longer spills out, but at constant speed around 60-65mph on the interstate, the coolant temp indicator will go up to 3/4 way from Cold to Hot, at lesser speed around 55 mph, the indicator will stay at half.

One thing I find it odd is that the coolant level still drops a bit from top of the radiator the next morning after it cools down. It acts as if it doesn't suck the coolant all the way back in from the expansion tank when the engine cools down, but the rad cap is only a year old and I don't know why this is happening.

And the belts were replaced at a Toyota Dealer. I don't know if they are good enough, and what would be the ones with higher quality in your opinion?

There is a little brass button on the cap in the middle of the gasket it has a small spring that holds it closed. When the radiator cools it draws a vacuum opens the little valve and sucks the coolant back in. Any leaks or a loose hose to the coolant tank and it won't work. You may also check and make sure the hose in the plastic tank is deep enough.

[centralman]

There is a little brass button on the cap in the middle of the gasket it has a small spring that holds it closed. When the radiator cools it draws a vacuum opens the little valve and sucks the coolant back in. Any leaks or a loose hose to the coolant tank and it won't work. You may also check and make sure the hose in the plastic tank is deep enough.

Thanks Maineah,

I have checked the hoses from radiator to expansion tank, they are tight, and the vertical hose has enough length to go all the way to the bottom. Before when the coolant is spilling out, the expansion tank will empty out after the engine cools down overnight completely.

I am not sure how to check the radiator cap. Maybe I tried to have it replaced and see what happens. Thanks for your suggestion.

[WME]

Is the bottom radiator hose soft?? Some have a coil spring in them and others are built very stiff.

If the hose is soft the water pump can make enough suction at high RPM to cause the lower hose to collapse and greatly reduce the coolant flow.

[centralman]

Is the bottom radiator hose soft?? Some have a coil spring in them and others are built very stiff.

If the hose is soft the water pump can make enough suction at high RPM to cause the lower hose to collapse and greatly reduce the coolant flow.

Thanks for your opinion. I have had all 3 rad hoses replaced earlier this year, so they are still ok.

[WME]

DID YOU check lower hose? I've seen the coil spring left out.

[centralman]

DID YOU check lower hose? I've seen the coil spring left out.

Yes, I have checked my mechanic used Goodyear #361 (Outlet-Engine Side) and Mackay #CH2426/16572-35030 (Radiator To Pipe) for the bottom rad hoses, they don't have coil spring on it.

[WME]

OK if you say so.

This is getting so weird that when you find the problem you are going to start banging your head against the wall, cause it was so simple.

[centralman]

OK if you say so.

This is getting so weird that when you find the problem you are going to start banging your head against the wall, cause it was so simple.

Probably you are right. But the two rad hoses I replaced didn't have coil springs on them either. From reading all the posts here, I have learned a lot. The only other thing I found odd with my MH is it's fuel consumption. I average 60-65 mph (more likely around 61-62mph) on the interstate or highway, and my MH is around 12mpg on fuel consumption. I have heard people here has upwards of 15mpg, that's the norm, could the two things be related?

[mmtoy1]

I had the same problen with the same motor in a sunrader. I changed hoses, belts, thermostat and went to half and half anti freeze or so I thought turns out mechanic put in straight water. However when I took the MH to montana from NY last year after the work no problem gauge stayed at a quarter way whole time. MH sat all winter with no anti freeze in it unknown to me I nevered checked it was on the bill and I trusted mechanic. Took MH out for the first time after winter and took a trip and I have the same problem as you heats all the way up at 60 ,65 and cools down at around 50, 55. I have no leaks and I dont think I had a freeze up but I have been watching this thread hoping you would find a solution before I started spending money. As for the fuel mileage I never did that well as some say they do I get 11 to 12 steady. I have heard these motor homes only get 17 to 20 when your selling them and when your owning them 11 to 14 is more realistic.

mm

[Derek up North]

I've a feeling that the 15mpg figure occurs when the speeds are kept to 50-55mph. Aerodynamic drag varies with the square of the vehicle speed, so if I remember my aerodynamics right, increasing your speed from 55 to 65mph will increase your aerodynamic drag by 40%.

[centralman]

I had the same problen with the same motor in a sunrader. I changed hoses, belts, thermostat and went to half and half anti freeze or so I thought turns out mechanic put in straight water. However when I took the MH to montana from NY last year after the work no problem gauge stayed at a quarter way whole time. MH sat all winter with no anti freeze in it unknown to me I nevered checked it was on the bill and I trusted mechanic. Took MH out for the first time after winter and took a trip and I have the same problem as you heats all the way up at 60 ,65 and cools down at around 50, 55. I have no leaks and I dont think I had a freeze up but I have been watching this thread hoping you would find a solution before I started spending money. As for the fuel mileage I never did that well as some say they do I get 11 to 12 steady. I have heard these motor homes only get 17 to 20 when your selling them and when your owning them 11 to 14 is more realistic.

mm

Thanks for your input. I always thought my MH's fuel consumption is worse than everybody else's. My Toyota MH is actually my first MH, so let's say the fuel consumption is about average at 12MPG, how does that compare with the other MH's (North American chassis ones)?

PS I will keep updating this thread as I will try to resolve the coolant temp problem, of course anything I find out I will let you know.

Also, I tried putting in Water Wetter additive by Redline, it doesn't have a noticeable improvement on the coolant temp.

[centralman]

I've a feeling that the 15mpg figure occurs when the speeds are kept to 50-55mph. Aerodynamic drag varies with the square of the vehicle speed, so if I remember my aerodynamics right, increasing your speed from 55 to 65mph will increase your aerodynamic drag by 40%.

Thanks, at least I know my MH's fuel consumption is not too far off from everybody else's!

[Maineah]

Thanks for your input. I always thought my MH's fuel consumption is worse than everybody else's. My Toyota MH is actually my first MH, so let's say the fuel consumption is about average at 12MPG, how does that compare with the other MH's (North American chassis ones)?

PS I will keep updating this thread as I will try to resolve the coolant temp problem, of course anything I find out I will let you know.

Also, I tried putting in Water Wetter additive by Redline, it doesn't have a noticeable improvement on the coolant temp.

Plain water will absorb more btu's then a mix of antifreeze distilled water even more the only problem is rust inhibiters etc. Know any one that works for the rail road? Locomotives use no antifreeze but they must use some type of additives. Yeah my 87 does 13-14 if I run 60-65 on the highway but that's a lot better they our friends with a V8 class C at 6-10!

[centralman]

Plain water will absorb more btu's then a mix of antifreeze distilled water even more the only problem is rust inhibiters etc. Know any one that works for the rail road? Locomotives use no antifreeze but they must use some type of additives. Yeah my 87 does 13-14 if I run 60-65 on the highway but that's a lot better they our friends with a V8 class C at 6-10!

Would taking the fuel injectors out and cleaning them by a professional company make the fuel economy better?

[Maineah]

I doubt if you would see much difference. We really are asking a lot of a 2.4 liter engine.

[minicruisin eric]

Nothin that hasnt been said but,

My '87 22RE was runnin hot (around 3/4) so I thoroughly flushed the system and added japanese anti-freeze. Its been staying under the 1/2 mark ever since.

[Derek up North]

I can see the flushing having an effect, but I don't think there's anything magical about 'Japanese antifreeze' that defies any of the Laws of Thermodynamics.

http://en.wikipedia.org/wiki/Laws_of_thermodynamics

[Diesel_Aggie]

Long interesting thread.

Is it possible that you have detonation? Since it only happens at high speed that equates with heavy load. Was the head milled when it was off slightly raising the compression ratio? Maybe try a few tanks of Super Unleaded or an octane booster and see if there is any change.

Is it possible that you have an exhaust restriction, maybe in the catalytic converter, that could cause the overheating under heavy load?