So as we all know, Ford temp gauges are garbage.

All my diesels have real temp gauges in them, and also keep my dash gauge working.

But on the diesels, theres 2 ports in a head, one for the temp light, and the other for the gauge, I just use the port for the light for my real gauge. Light doesn't work no more, but dash gauge does.



Now for both my '89 and '94 300 EFI inline 6's, that has that electrical connector on the heater core outlet on the thermostat housing, I am assuming that's where the gauge gets it's reading? How would I go about putting a real gauge in this engine, and keep my dash gauge working as well?


Thanks!

 

No one? Did some research on this, hardly any threads on it, and non showing pics or having any good explanation.

Only 1 I found, that it was a challenge on the 300 cause the real gauges only had 6' of wire, and said something about the sensor being on the passenger side of the engine?

 

John,

On my 4.9, the PO installed an aftermarket sending unit in the stock location, which is on the RH side of the block, just under the rear-most (#6) intake runner. Because I like to have working gauges in my dash, I'm going to put the stock sending unit back in. However, I also like the option of an aftermarket gauge, so I was able to score a thermostat housing with a port for adding a gauge, sending unit, whatever. If you need me to, I can find a picture of it for you.

Does this help you out?

 

Here, like this one: More Information for FOUR SEASONS 84913

 

Something like this might work:

Greddy Radiator Hose Adapter with Temp Gauge Fitting 38mm at RallySportDirect.com

 

That's the engine coolant temperature sensor used by the computer.

As mentioned the factory temperature gauge uses the sender below
the number 6 lower intake runner.
There is nothing wrong with accuracy of the factory temperature sender/gauge.

It's the oil pressure gauge that was basically a idiot light. Replacing
the oil switch with a real sender, cutting a resistor out on the back
of the dash cluster and soldering in a jumper wire corrects that problem.

 

Thanks alot for the links and pics!!! Just what I was looking for!


I really like that custom thermostat housing. But that brings me to a question.

Can one simply put a T where that computer sensor plugs into on the outlet for the heater core, and run a real gauge from there, or would that affect optimal performance of the engine computer coolant sensor if it's not in direct flow of the coolant?



As for the gauges not being the problem. I won't argue for the 92+ trucks as I don't know much about their clusters yet, however, 91 and older trucks, and vans till 1991 have unreliable gauges, all of 'em.

I'll give you a perfect example. In my '89 F150. I swaped cluster. It originaly had a basic non tach cluster. I swapped in a tach cluster, and reset the mileage to keep the original mileage of that truck going.

The original non tach cluster in that truck, the temp gauge would reach and sit inbetween the N and O of NORMAL. (cooling system has been completely re done)

Since i've swapped the cluster with the tach in it (from an '87 6cyl F150), the temp gauge, rides inbetween the 2nd COLD line, and N. It doesn't even get close to the N.

And btw, since this was an 87 cluster, I had to swap the oil pressure sender on the engine, for the oil psi gauge to work, and it works just like a real one, it goes up as the revs come up, and goes down when it returns to idle.

 

Here's a picture of a 87-91 cluster. One without a tach and one with a tach.

The letter screening is different for the temperature gauges. Also the gauge lettering is in a slightly different position relative to the pointer. This could be the reason why you say the pointer appears to be in a different position after you swapped clusters.

 

The pointer in my non tach cluster never sat that far down. Dead cold, it sat 1/4" under the first Cold line, and fully warmed up inbetween the N-O of NORMAL.


My tach cluster now sits inbetween that 2nd Cold line, and the N. So it doesn't even reach the N.


In my 1990 F250 Diesel, it sat exactly at the same spot as in that 2nd pic, just a tad under the N.




My '85 E350 Diesel van, rides right on the O and my real gauge on 192*

My '87 E350 Diesel motorhome, rides on the M-A of NORMAL and real gauge reading around 190*



Heres a shot of my '89, fully warmed up on the highway doing 55. (this was before changing the oil sender unit on the engine, witch is why my gauge wasn't working).

 

No, you can't put a T where the computer guage is at because there won't be enough flow for it to be accurate. A new housing is super cheap and probably your best option. I found a practically new one at a salvage yard for $3.

 

You found one of those thermostat housings with that other port on it in a salvage yard? Didn't know Ford had these.

 

I sure did. Got lucky as it was brand new. I recommend getting one at a local aftermarket parts store of your choice if you don't fancy ordering items online.

 

Will look into it! Thanks alot!

 

You're welcome, sir. Let us know how it works out for you.