ctrain22

I have a 68 400 and am thinking about installing a set of aftermarket temp and oil gauges. Not that I don't trust idiot lights, but.....I don't. I would like to keep the factory light setup and the mechanical set up. The oil pressure gauge is no prblem to install with a splitter for the sender and hose kit, but what about the temp sender? I have the factory sender in the passenger side manifold hole and the distibutor vacuum switch in the drivers side hole. Is there another place I could put an aftermarket sender for water temp? What suggestions do you all have?

joe_padavano

Unfortunately, the temp sender needs to be in the coolant flow. You can get an aftermarket sleeve that goes in the upper radiator hose and provides a bung for the temp gauge.

68conv455

I'm confused. Doesn't the coolant flow split at the front of the engine? A quick look at the lumps on the intake manifold suggest that the left side would be coolant too because the intake runners can be identified with 4 per side coming from the carb.
What am I missing?

joe_padavano

Not sure what you mean by "split", but the intake has a coolant crossover at the very front of the manifold. This is actually the coolant OUTLET, since the water flows into the block at the water pump and flows out to the radiator from the thermostat housing.

The problem in the original post is that there are not enough threaded bungs in that crossover to accommodate the TVS, the existing coolant sender, and the new one for the gauge. Oil pressure senders can be connected with a tee, but this does not work for coolant senders, which must be in the actual flow of coolant.

defiant1

I am looking to do the same thing with my 350, but I asked the guy at the parts place for a "splitter" for said application and he looked at me like I was speaking Swahili. So, what exactly am I looking for to hook up my oil pressure tubing kit and maintain my dummy light?

d1

Bluevista

There was just a thread on this , dude in Italy was looking for one.

1/8" NPT brass fitting, I got mine at Summit Racing, N.O.S. sells them to hook up that stuff. You can do the same thing with a short nipple and female tee but it just doesn't look as clean, that stuff you can get at the hardware store.

defiant1

Thank you very much, I will get one ordered tonight.

DSM

You should be able to get that brass fitting at any well stocked auto parts store. I got mine at my local O'Reillys for about $6. It's a Dorman 43026 http://shop.oreillyauto.com/ProductD...rtNumber=43026

Here is what it looks like installed...

defiant1

Hey Don,

Thanks for the photo, definitely helps visualize it better. I probably overspent on the one I got coming from Summit. My biggest concern is screwing it into the intake manifold. I got A/C brackets that hug the front of the intake and make it a chore to get at the sender/fitting.

Out of curiosity, on your motor what is the gray/silver sensor next to the water temp sender? Is that a mechanical water temp sensor? Also, for your oil pressure line, is that nylon line covered in rubber hose or did you use copper line?

Thanks again

d1

Lady72nRob71

Sure looks like it - I have an identical one on my Ford...
The aftermarket intakes seem to come with extra bungs for temp. sensors and switches for maximum flexibility.

DSM

Yes, the grey/silver thing next to the water temp sender is the sensor for a mechanical water temp gauge. The oil pressure line is nylon, but the sleeve is actually a high-temp silicon made for wiring harnesses. I wanted to hide the nylon tube, plus the sleeve offers some protection agains heat and abrasion.

1966_F85

Here is what you need for the temp sensor if you are using the stock manifold:

http://www.summitracing.com/parts/ATM-2280/



It installs into one of the heater hoses.

defiant1

So, it doesn't matter which heater hose? I'd like to keep my water temp dummy light so this is a good option.

Thanks for the link.

d1

DSM

There are a couple things to watch for when using the heater hose adapter.

First, if your car has A/C, then you have a shut-off valve on the heater hose circuit. I'm not sure how much coolant flow still goes through this circuit when the valve is closed (i.e. heater is off, selector set to "cold"), but it might not be enough to get an accurate reading on the gauge.

Second, the Autometer 2280 adapter (which fits 5/8" heater hose) only has a 1/8" NPT port. If you are planning to use an Autometer electric gauge this isn't an issue, but if you want a mechanical gauge it won't work.

If you decide to go with an electric gauge and use the heater hose adapter, you might want to use the #2281 adapter (looks identical to the #2280). It fits 3/4" heater hose. Location wise this is a better choice - the long run of hose from your water pump to the heater core is 3/4" (the short hose from heater to engine is 5/8") so it makes it easier to package. And, you ideally want the gauge to read before the heater core. The heater core is just a small radiator, so the coolant coming back to the motor will be cooler than the coolant going into the heater core. In other words, the gauge will read colder than true engine temp if it is in the 5/8" return hose.

Another option would be to use the #2282 or 2283 adapter in your top radiator hose. It comes with all the correct fittings for either electric or mechanical gauges.

1966_F85

I knew if i chimed in with an example, someone else would be able to fill in the blanks

defiant1

Great explanation. Looks like I will need a new water temp sender in order for it to fit the 3/8" adapter. Does anyone know what temperature rating the stock electrical dummy light is rated for? I see electrical sender in the 250 and 300 degrees range. Not sure if there will be any compatibility issues? Also, to clarify I already installed a mechanical water temp gauge in place of the original electrical sender.

d1