Switch placement?

[Tractorcedric]

Neighbor has a 1950 Chevy 2 ton with a 235 in it. Sometime in the past a good sized electric fan was placed in front of the radiator core. Power for the fan was just hooked right to the key switch. Last time I drove the truck it started to get hot and I noticed the fan was not running. So I had to hold the key in just the right place to get the fan to stay on. He just uses it to pick up small bales with a hay loader. I have replaced the key switch with a heavy duty Pollack switch. Now the fan runs when key is on. I would like to put in a relay and use a temp switch to run it. The heater has been unhooked. So I could put the sender/ switch in the thermostat housing or the side of the water pump. Witch would be the best? Thanks

 

[rustred]

I would clean the rad out then see how things go. Cant see how having a fan in front of the rad with the engine fan behind the rad. If its a must just wire it to an on and off switch and watch your temp guage as when to switch it on.

 

[timcasbolt]

I've seen switches like that at Summit Racing Equipment.

 

[redforlife]

What's the reasoning for an add on electric fan? Is it an additional fan to the factory one, or was the original eliminated for some reason???

Kind of a big difference in its importance between being an additional, or being the only fan for the system. And which of the two it is, plays a big part in how it should be rigged up.

If it's the only fan, it should be rigged up to operate as so. But if it's an additional fan, it should be rigged up to aid the original in overheating situations.

A hot summer day hauling hay will test out any radiator needing cleaned out. Both air and coolant passages. If you flush out, and blow out the radiator, you may find that you don't need an extra fan.

 

[tomturkey]

Those older trucks seemed to have hugmongous radiators with a large capacity. I would guess as rustred indicated that the radiator needs a flush. The common practice on the farm was to use water, well water, which tends to be very hard, and drain them before cold weather. I think it may be rusted and scaled up, losing its cooling capacity. BUTTTTT, if the heater is non functioning you could install a temp switch in the heater hose port, maybe. It WOULD be much easier than a radiator flush removal repair for no more than it probably gets used. gobble

 

[leroy in ne]

redforlife, Have seen 216's replaced with 235's where there is a problem with fan to radiator clearance. One way to fix was press the flange back on the water pump, use a pulley with different offset and a flatter fan. If I remember right a fan from an early 50's ford V8 was used. Hard to remember from 40 or 50 years ago.

 

[Geo-TH,In]

You asked about adding a relay.
I'm not sure you can find a 6v relay.
Here is a 12v relay you can buy from Amazon.

If you had a temp sensor that turns on an idiot light when it gets hot, you could use that sensor to turn on the relay.

 

[RJKeith]

No, do not use the sensor for the idiot light. The fan needs to run at a much lower temp to engine from getting hot. The idiot light is to warn you the engine has become much hotter than it should be. Most tractors I have seen has a temp sensor in the water jacket on the block.

 

[Hobo,NC]

Google this then you can pick you range.

FAERSI Fan Thermostat Temperature Switch 200 to 185 Degree Electric Engine Cooling Temperature Sensor Switch with 3/8" Pipe Thread for 10" 12" 14" 16" Fan

A radiator cooling fan is a ell of a load it needs to be hard wired in no push connections. Don't cheap out it will come back to haunt ya. This is the relay I use most all the time.

https://www.amazon.com/gp/product/B07SJVCW4P/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

And another

https://www.amazon.com/dp/B07T35K8S2/ref=syn_sd_onsite_desktop_0?ie=UTF8&psc=1&pd_rd_plhdr=t

 

[miangus]

Yes, I have one it just inserts into the radiator fins and is connected to a fan relay.

 

[DoubleO7]

Use a thermal switch for electric radiator fan like this.
No other switches or relays needed.

$13 switch

 

[Hobo,NC]

If that switch could tote a 30 amp circuit the blade push on connection won't. Even the one Geo posted the heat build up on the blade connection at the relay will come back to haunt ya.

This is a case the load needs to be hard wired no push on connections on the load side.

Why you don't play with this its not like the heater blower motor quits blowing, this can and will destroy the engine.

 

[Geo-TH,In]

What temp does the idiot light come on?

Above or below the boiling point of coolant under pressure?

The engine coolant temperature warning light is an important indicator that alerts you when the engine is overheating. The light usually illuminates when the engine coolant temperature exceeds the normal operating range, which is typically between 195F and 220F 1. However, the exact temperature at which the warning light comes on can vary depending on the make and model of your vehicle.

Antifreeze and water mix under pressure boils at a much higher temp. 230-240 or higher

Each to their own. Do what makes you happy.
Find a temperature sensor that is typically used to turn on the electric fan on today's cars.

Very few people are offering ideas on how to wire the car.

 

[Tractorcedric]

I don't know if the engine has been replaced. But the fan is small and is way low towards the bottom of the radiator. Also don't know if it needs flushed. I do know that someone else installed the big extra fan and just hooked it to the keyswitch. I have ordered a grounding switch to put in the water jacket and will hook it up with a good relay. When I drove the old truck for the neighbor this summer, if I could get the fan to run it would cool down. Truck is only used a few hours a year to haul small bales. thanks for your info.

 

[Rich'sToys]

I don't know all the specifics, but some of those engines used a different water pump which made the fan higher or lower. If the engine was replaced, it was sometimes necessary to change the water pump.
Go to stovebolt.com and do a search of their forums. This topic has been covered a lot over there.

 

[Geo-TH,In]

My relay is rated at 30-40 amps.
My relay is the same used in cars today.
You need a relay to keep power away from the ign
sw and to turn the fan off when you turn the car
off.

How amps do radiator fans use?
What relay would you recommend?

 

[Hobo,NC]

(quoted from post at 04:19:22 11/02/23) My relay is rated at 30-40 amps.
My relay is the same used in cars today.
You need a relay to keep power away from the ign
sw and to turn the fan off when you turn the car
off.

How amps do radiator fans use?
What relay would you recommend?

Com down brother Geo, the issue lies more in the connections. You know the weak link in the system. The relays I posted can be hard wired, hard wired correctly that takes the weak link out of the equation.

I have wired a few using's your replay they bit me : (. That weak link is the enemy. I like using the fan assy off a 1990 Ford Taurus they can be retrofitted to most anything and get'er done. They will pull in the mid to high 20's. That's quite a load so use 10ga wire solder the eyelet connections on and any where on the supply are load side and they will not be popping in the door with a wiring system malfunction.

There it is you can do it anyway you want too its yours's you accept the responsibility. Overkill it life will be good.

https://www.rockauto.com/en/catalog...531,cooling+system,radiator+fan+assembly,2181

 

[T.R.K.]

My first thought is why did they do away with the fan on the water pump? What engine is in the truck now?

My '53 1 ton 235 has a fan there, right on the water pump shaft. The thermostat in the water neck on the engine controls the engine temperature.

 

[Brown David]

(quoted from post at 13:22:50 11/01/23)
If that switch could tote a 30 amp circuit the blade push on connection won't. Even the one Geo posted the heat build up on the blade connection at the relay will come back to haunt ya.

This is a case the load needs to be hard wired no push on connections on the load side.

Why you don't play with this its not like the heater blower motor quits blowing, this can and will destroy the engine.

That switch would ground the relay which would provide power to the fan.

Very little current would be going through that switch.

Just about every car or truck produced today energizes the cooling fans via the properly rated relays.

This post was edited by Brown David on 11/01/2023 at 05:55 pm.

 

[Tractorcedric]

Yes the fan is way to low to do any good were the water pump is!