351 w water pump heater bypass

[Lloyd]

Thanks Roger I've emailed them for a usa distributor. I like the two speed capabilities connect the low speed to the current system thru a relay and put a manual switch for the high speed.
I'm definitely looking for quality when i do something i want to do it once i don't mind paying for good stuff.
LLoyd

 

[Ian Anderson]

How accurate is your gauge?
Example
My car day driving no lights gauge reads 82 to 85 degrees Fans kick in around 88 and back off at about 84. (Volt meter reads 14.5 volts or there about)
Now drive at night with lights on and my gauge shows about 4 - 5 degrees hotter but fans do not come on. Volt gauge has dropped to 13.5 ish when driving.

After searching I believe, though have never tested it with an IR thermometer or whatever, my gauge reads high as the voltage drops. In my case an ETB Gauge and matching sensor) that runs without a voltage stabiliser.

Are you perhaps worrying without cause?

Ian

 

[Lloyd]

Have not tested the gauge but i have a 180 degree thermostat and the current fans kick on right about the 180 mark. So I'm guessing the gauge seems to be correct.
At 220 i am not spewing any water out of the overflow runs fine has never gone over 220
i shut off the a/c and it will drop back to 180-185 range but it gets hot real quick inside the car.
the temp also drops if start moving at speed again, That's why i'm hoping bigger cfm fans will help
LLoyd

 

Hi Lloyd,
A few thoughts on temperature:
- at 13psi water boils at 244F at sea level
- with 50/50 anti freeze this will go up to around 251F
BUT
- as Ian says, gauges and senders are not 100% accurate
- also there maybe hot spots remote from the sender
- also you may get well above sea level
SO
- allow a decent safety factor when specifying a Thermoswitch to come on

I'm thinking no higher than 220F.
There is a huge volume of thermoswitches over here in UK but most have metric threads. I'm in the process of fitting a Hella 100/95C (212/203F) 2 pole switch in the inlet manifold water jacket port just behind the thermostat. The switch has a 14mm thread so I need to get an adaptor to the 3/8 pipe thread on the manifold. My current switch comes in at around 185F which is low and means that the fans are running most of the time. I have a manual override to switch on so really just need the auto as a fail safe.
I thought about doing some trick stuff with the high and low speed options but Kenlowe said just use high speed and keep it simple - suits me!
Cheers
Roger

 

Hi Lloyd,
Just an update on a thermo switch for the fans. I actually ended up getting a 100deg/95deg (212F/203F) switch made by Febi/Bilstein in Germany. All looked good but when tested on a rig the switch closed at 106.5 and opened at 90.5 deg (224F/195F) which is too far away from spec to be comfortable.
The rig is just a meter across the terminals and the switch suspended in a heated bowl of oil with a temperature probe in it.
The moral of the tale is carefully test everything that's critical ! As I'm in no rush I have sent a query to the switch supplier.
Cheers Roger

 

[Randy V]

Sometimes electrical sending units can drift from spec due to the method of installation. Because I have been bitten in the past - As a rule, I only put sealant on the upper half of the pipe threads of the sender. This will allow the bottom half to make good ground contact with the engine component it is threaded into.
This also requires a very good ground from the engine to the battery. I also run grounding straps from the intake manifold (where most senders are threaded into) to the chassis.
Not saying that this was your problem though...

 

I run a two pole switch. So in effect it's just a switch in the line and the body earthing is not necessary.
Cheers Roger

 

[Bob Putnam]

The ERA uses a fan switch that measures the temperature of the water returning from the radiator, not exiting the engine. That way, the fan doesn't come on until it's actually required.