[old-school-ram-van]

hi everyone,
I got a 1990 b350 5.9
got an issue with over heating. not sure if it's the gauge on the dashboard or it's actually over heating. when I leave it ideling it stays near the middle but if I drive it goes way up. there is no signs of over heating. no steam or lights on the dash. antifreeze is at correct level in rad and over flow container.
unfortunately I only been able to drive for a few blocks since it's not plated.
what would be the best way to know for sure if it's over heating?
also the radiator was changed 4 years ago.....any help would be appreciated thanks

 

[punkstarkitch]

I have a 98 5.9.
Check to see if the belt is turning your water pump. Also, your impeller could be shot and not circulating the coolant, and maybe it could be the thermostat and temp sensor

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[old-school-ram-van]

I was thinking to start with thermostat and water pump/sensor as you mentioned.
It's just strange that it could sit idling fine. Will definitely check all you suggestions. Thanks .Will update soon as I get in there.

 

[Pntyrmvr]

Start with the factory service manual and follow the flow chart for overheating.

Remember the van is over 30 years old.

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[old-school-ram-van]

I been trying to fine the service manual. I order one online and it wasn't the correct model or year they don't have it anywhere. Need to find a paperback original. ...if anyone can provide a copy of that section would be very helpful and appreciated...thanks

 

[Pntyrmvr]

For $30 - 40 on eBay.

Got your Rock Auto under your year and model. Under literature I think and order the FSM on CD.

Ez.

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[Pntyrmvr]

Go to Rock...

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[thedarbs]

Start with the factory service manual and follow the flow chart for overheating.

Remember the van is over 30 years old.

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If it is 30 yr. old the radiator is more then likely 3/4 plugged

 

[halfbreed1951]

hi everyone,
I got a 1990 b350 5.9
got an issue with over heating. not sure if it's the gauge on the dashboard or it's actually over heating. when I leave it ideling it stays near the middle but if I drive it goes way up. there is no signs of over heating. no steam or lights on the dash. antifreeze is at correct level in rad and over flow container.
unfortunately I only been able to drive for a few blocks since it's not plated.
what would be the best way to know for sure if it's over heating?
also the radiator was changed 4 years ago.....any help would be appreciated thanks

It sounds like a stuck closed thermostat

 

[guyonearth]

It sounds like a stuck closed thermostat

No, it doesn't, or it would just overheat.

 

[guyonearth]

Possibles:
0. LOW COOLANT.
1. Plugged radiator, can't circulate enough coolant to cool engine at speed.
2. Front of radiator plugged with lint, dirt, leaves, bugs, etc.
3. Water pump belt slipping.
4. Water pump impeller rusted away.
5. Fan clutch not working at all.
6. Fan installed backward or wrong fan (don't laugh, I've seen this, it does exactly what he's describing).

 

[old-school-ram-van]

-coolant is at correct level
-radiator is 4 to 5 years old and clean all around
-thermostat not sure about but it's worth replacing, but also believe it would over heat all the time if closed as mentioned
-water pump belt will need to check it
-the fan cluch will need to check it, rockauto has 2 different ones thermal and non thermal not sure which is better
-not sure about fan installation or not correct one

will probably replace most of these prices for parts seem very fair ..

 

[44MagLeo]

One thing you can try is to pick up an after market temp gauge. Hook it up , then drive it around same as you ha ve been.
If it reads ok then try replacing the stoock sending unit.
Leo

 

[JamesI]

My guess is the wax in the thermostat has gone wonky, and the thermostat is stuck half open.

 

[LTDLTD]

hi everyone,
I got a 1990 b350 5.9
got an issue with over heating. not sure if it's the gauge on the dashboard or it's actually over heating. when I leave it ideling it stays near the middle but if I drive it goes way up. there is no signs of over heating. no steam or lights on the dash. antifreeze is at correct level in rad and over flow container.
unfortunately I only been able to drive for a few blocks since it's not plated.
what would be the best way to know for sure if it's over heating?
also the radiator was changed 4 years ago.....any help would be appreciated thanks

Get a thermostat that is about 10 degrees Fahrenheit lower than the one installed. Vapor lock
( if in the future it were to occur means a too hot gaseous condition within the gas tank. Loosen the gas cap.....relieves the locked in vapors so to speak. Expired tags only occur 6months and one day after supposed expiration date at DMV.
That's why they let you pay late for up to 6 months with a penalty of course. Get a "Red Tag"from DMV for your rear windshield if you can't get pass smog.