350 temp switch

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woody

woody

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Worked on installing a primary electric fan...everything going smooth until I prepare to pull the plug from the passenger side head to put in the temp switch...and discover that the sender will be either WAY too close or actually contacting my hugger headers....

Leaves me with two options....1, put in a L pipe on there and point the sender up or (better) 2, put the sender in an existing spot on the intake manifold.

Any opinions? I'm leaning manifold, figger as long as it switches on and off, I don't care....
 
Depends on what manifold you have, but for the stock TBI I want to say your options are:

In the heads on either side - close to the headers, I run the temo guage off of the left one
In the rear heater hose location - that's where mine is on the 40
In the water pump - dunno how the flow would affect the switch and a PIA with the serp belt from the van
In the location just to the right of the T-stat. I think this is the best place for the ECM sender though
Some manifolds have another one just to the left of the t-stat - that'd be good
Get a t-stat housing that has one cast into the housing. They did that a lot in the era of TVSVs
T off of the ECM sender or the guage sender. The guage would be better -neither would be all that good, IMHO

Putting in a thermal switch is way better than a manual one. It's no good to forget to turn it on.
 
I had my fan and temp gauges "T"ed off the drivers side head. The contraption stuck out so far that tha air movement on the road dropped the temp gauge to cold even though it was not. I would try to keep the switch tight to the engine. JL8)
 
OEM GM switch turn the fan on at 220-225 on most Cruisers in our area this is too hot, we all just use a toggle.
Butch
 
I agree, that's why I use a 180* turn on 160* turn off Hypertech switch. I hate concentrating on something and notice that my temp has climbed too high when I wasn't paying attention. I do have the relay set up with an over-ride switch as well.
 
"JET GM Fan Switch
Keep your engine cooler.
We bet you didn't know that your GM computer doesn't switch the fan on until your engine gets to 225 degrees. That's not the best thing for engine power or life. This JET fan switch turns on at a much cooler 200 degrees and cools until the engine is back to 185 degrees. Comes complete with installat... "

This is the Jet switch I purchased from Summit....IMO, it outta work....

In looking at my setup, the best spot appears to be a threaded spot on the back of the intake manifold behind the TBI unit....

Good idea, adequate idea, or really poor location??
 
Woody,

Because of temperature differences I'd suggest going with the front of the intake manifold so you're getting temp just before the water returns to the radiator (i.e. highest temp readings). Do not use the water pump since that's the cold water coming into the engine. The cylinder heads are an ok place for one except they fluxuate in temp much more as cylinder output goes up and down (i.e. temps jump up as soon as you put your foot in it). Good luck.

Rice
 
hey, I know it's different but, I installed a flex a lite dual fan kit in my F150 2 weeks ago and their temp control module has a probe that goes into the radiator hose inlet. works good and accurate and no space problems. I am pretty sure they are adaptable to others and not hard to wire in either.
 
I wouldn't hesitate to install the sender in the "cool water inlet" of the water pump... in fact, that's where my sender is, because the fan only need to run when the radiator can't dissipate the heat on its own, meaning... the 'cool water inlet' isn't so cool anymore... I'm using the flex-a-lite sender in the lower rad hose, and the temps stay more consistent now... And no, I'm not worried about the bulb breaking off and getting jammed in the water pump.

Anyway, Woody... I vote for in the top of the thermostat housing, if you can't put it anywhere else... Since they're all interchangable, I'm sure you can find one with a threaded hole in it... Mine looks to be some kind of stock one, and my temp gauge is threaded into it...

I can snap a pic if ya want...
 
looks like it might be junkyard hunting time....my guess is, if the fan gets installed prior to CM04, it will end up on a toggle for now...and upgrade to a autoswitch later.

Great input! Always nice to have LOTS of ideas.....lol
 
I purchased a speedwaymotors.com item # 91064013, and i removed a silicon plug and it was fully adjustable. installed in the the intake, as the temp gauge is in the left head.

Many different companies make adjustable or non adjustable temp switches, and the are pretty cheap.

I liked the speedway as it is a single wire hook up (it grounds my relays). I have three switches, one is slow, one is fast and the other is manual override ground. Wired to illuminate when the fan kicks on.

dont know if you have all your other componets, but i found really good relay holders in reliants or renaults (foreign boxy thing i think that is what they are called) and bosch relays from 30A - 75A in other german cars, audi has lots. Older or mid 80's cadilliacs have a weatherproof holder for these same bosch relays.

BTW i finished my toreass fan install about 2 weeks ago, under $40 to do it all.

The cast in thermostat housing would work. Also toreass have a thermo switch located in the thermostat housing, 2 wire, i have one but have not set it up to test temp opening or closeing on it yet.
 
More.....
 
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