Question Regarding Coolant Temperature

[centralman]

Hi there, I have a 1987 Toyota Dolphin MH. It has a 22REC engine and 4 speed automatic transmission. As you know the coolant temperature guage has a wide normal area (indicated by within the white boundary). My question is this: My MH usually stays only 1/3 of the guage when operating in moderate speeds (below 40mph). Once it gets faster than that the temperature needle begins to rise and if maintained at around 55mph the temperature guage will be at around 2/3 from the top. If it maintains at around or above 65mph it will go right up to the maximum operating temperature range (That white boundary on top), it won't go into the red zone, but it'll stay there.

The car had a major tune up last year and as far as I can tell everything's running fine except the behavior of the engine coolant temperature (It's most certainly different that from an ordinary passenger car, which will always be around the mid mark and stay there in any driving condition. So, is this normal on a toyota MH? Could there be any underlying probelm?

Many thanks for your reply and assistance.

[Bodybagger]

Once it warms up, the needle should stay put.

Your thermostat needs replaced. You need a 192 degree thermostat. Do not use a "fail-safe" type thermostat. The $4.99 thermostat is what you want. Have the cooling system flushed so the crud does not make the new thermostat stick.

There could be other issues, but a $4.99 thermostat is a no-brainer to try first. You don't even want to think about the other issues until you try that thermostat.

[centralman]

Many thanks. I have put the car into the garage for maintenance and will ask for the thermostat replacement, too. Will let you know once I have gotten it back to see if the symptom still persists.

Oh, by the way, there's one more thing I'd like to ask. The steering of the MH is not stable, I don't know if there's too much freeplay on the steering wheel or some other thing but when the MH is on the highway (especially higher speed) it tends to swing a bit when there's crosswind and hard to control the MH to keep it straight, I wanted to fix that too because it's kinda dangerous, any ideas?

[turtle]

Oh, by the way, there's one more thing I'd like to ask. The steering of the MH is not stable, I don't know if there's too much freeplay on the steering wheel or some other thing but when the MH is on the highway (especially higher speed) it tends to swing a bit when there's crosswind and hard to control the MH to keep it straight, I wanted to fix that too because it's kinda dangerous, any ideas?

You can add a steering stabilizer if it does not have one. If it does have one check to make sure it is still dampening. This is mainly to give a more solid feel when turning the wheel and to dampen wheel shimmy when hitting pot holes.

You are GOING to get blown around in a cross wind.

Stiffening the suspension with Bilstein shocks will help the lean but you will still get blown around in the lane even if you do not lean.

[nibs]

Just as a reference, my temp needle points to the T except on steep hills on hot days, it might go up to the M especially if the a/c is on, I don't normally turn off the a/c unless the hill is exceptional.

In an emergency, turn the heater on, full blast & hang your head out of the window.

As well, these units are light and large, great sails, you will get pushed around by passing trucks and wind gusts. If you are ever in a very windy situation and do not feel safe driving, park with your nose to the wind, or tuck in behind a building. I have done both in our 5th wheel, but never needed to in the Sunrader.

[centralman]

You can add a steering stabilizer if it does not have one. If it does have one check to make sure it is still dampening. This is mainly to give a more solid feel when turning the wheel and to dampen wheel shimmy when hitting pot holes.

You are GOING to get blown around in a cross wind.

Stiffening the suspension with Bilstein shocks will help the lean but you will still get blown around in the lane even if you do not lean.

Thanks for your suggestions. I don't know if it has a steering stablizer, I check the KYB catalog and finds that there's only one (steering damper) for 4WD pickups, will that fit?

[turtle]

Thanks for your suggestions. I don't know if it has a steering stablizer, I check the KYB catalog and finds that there's only one (steering damper) for 4WD pickups, will that fit?

You would have to call KYB and ask them if it will work on a 2wd.

Rancho lists one for Toyota 2wd

http://www.shockwarehouse.com/site/product.cfm/id/13885/adid/232?utm_medium=shoppingengine&utm_source=googlebase&cvsfa=1900&cvsfe=2&cvsfp=13885

[centralman]

You would have to call KYB and ask them if it will work on a 2wd.

Rancho lists one for Toyota 2wd

http://www.shockware...e=2&cvsfp=13885

Thanks, my MH is at 90,000miles and it is at the mechanic shop to have the timing chain done along with head gasket, water pump, oil pan gasket, valve cover gaskets etc ...

So, it's gonna be expensive everything added up together, so I think due to budget constraints I have to go with KYB Gas-A-Just (can't afford Bilsten:()

I hope after this major work done it can last another 5 years ... then I'd be happy!

[centralman]

Update: After a couple of weeks in the garage and a record breaking repair bill for me, I got the following done:

(1) Mobil 1 5W50 Oil Change + Liqui Moly MoS2 Oil Treatment

(2) Timing Gear Kit Replaced including Timing chain, gear, tensioner, gasket

(3) Head Gasket Set (This should include all those intake, exhaust, valve cover ... etc gaskets)replaced along with Head Bolts

(4) Oil Pan Gasket replaced

(5) Aisin Water Pump replaced

(6) Napa Medium duty ATF cooler added

(7) Thermostat and gasket replaced

(8) Coolant flushed and replaced with Toyota Long Life Coolant

(9) Eneos Synthetic ATF flush along with filter and AT Pan Gasket

(10) KYB Gas-A-Just shocks replaced for front suspension

(11) Aisin Oil Pump replaced

(12) Whole floor replaced with hardwood panels

(13) Bosch O2 Sensor replaced

(14) Bosal Header to Catalytic Converter exhaust pipe replaced

(15) Napa Fan clutch replaced

I know the car has this and that problem before and hopefully after all these I will be able to drive it for another 60,000 miles.

Took it for a spin today, roughly 120 miles. Engine temp will stay at 1/3 on the guage now when the speed is lower and will climb to 1/2 when climbing slope and above 65mph. Huge improvement from before. Also the MH doesn't tend to swing that much now after the front shocks replaced.