Oil and Temp senders to square body manual gauges finally

[LSSierra]

Ok. I spent hours searching this site as well as LS1Tech and could NOT come up with a viable solution to keeping my factory gauges for OIL and TEMP while using some kind of senders in the LS motor to keep my stock gauges. SOLVED. Here is what you will find:

Most tell you to drill/tap the passenger side head or water pump. I didn't want to do this...cause why would you. Others use a T in a heater hose or something to that affect...why do that? I ordered the Summit Adapters and realized pretty quick that my stock 87' senders didn't fit through the new adapters because those adapters are for ELECTRIC gauge senders. I wanted MANUAL.

So...I found a place called "FASTENAL" here local which has all kinds of fittings. After all this research, head scratching, avoiding tapping/drilling because my motor is together and running - gauges were the last step for me -I ended up with a simple, one piece adapter for both the OIL and TEMP senders.

Stock OIL sender thread is 1/2" and I simply got 1/2" to 3/8" adapter. I know this sounds crazy cause it isn't "Metric" but the threads matched up and I put thread sealer on there. What do you know...I have a working, stock, oil pressure gauge with a simple adapter NOT sold by Summit for 500% mark-up. Don't get me wrong, Summit is awesome, but they don't have adapters to use for an Gen III/IV motor to a square body gauge setup using stock senders for manual gauges.

For Temp, I simply got the same kind of single piece adapter (looks just like all the ones from Summit etc but different size) and went from 3/8" for stock temp sender end to 1/4" to put in passenger side of head. Now I have a temp reading. Once I get the coolant back in tonight, I'll update on where my gauge reads hot since it's the original sender, but funny enough, it always ran a one third level with my 305 hot, so I'm gonna go on a limb and say it'll be near center.

I wrote this lengthy thread because I'm sure there will be other square body swappers wanting to use stock gauges and senders. I'll post pics of my adapters tonight or tomorrow. Good luck all.

[mongocanfly]

if it works for you then ok...but I'd be careful about forcing standard threads Into metric holes..not a good idea especially in aluminum

As a side note at work we have some water cooled rolls..one end has standard right handed pipe thread and the other end has left handed pipe threads...I know it may sound impossible but you can screw left handed npt into right handed npt holes and vice versa...but they will leak like crazy..

And some metric bolt threads are very close to a standard thread so much so that they'll screw in part way..but that's not a good idea either..sometimes just because you can doesn't mean you should..

[1970 CST Short Wide]

Originally Posted by LSSierra

Ok. I spent hours searching this site as well as LS1Tech and could NOT come up with a viable solution to keeping my factory gauges for OIL and TEMP while using some kind of senders in the LS motor to keep my stock gauges. SOLVED. Here is what you will find:

Most tell you to drill/tap the passenger side head or water pump. I didn't want to do this...cause why would you. Others use a T in a heater hose or something to that affect...why do that? I ordered the Summit Adapters and realized pretty quick that my stock 87' senders didn't fit through the new adapters because those adapters are for ELECTRIC gauge senders. I wanted MANUAL.

So...I found a place called "FASTENAL" here local which has all kinds of fittings. After all this research, head scratching, avoiding tapping/drilling because my motor is together and running - gauges were the last step for me -I ended up with a simple, one piece adapter for both the OIL and TEMP senders.

Stock OIL sender thread is 1/2" and I simply got 1/2" to 3/8" adapter. I know this sounds crazy cause it isn't "Metric" but the threads matched up and I put thread sealer on there. What do you know...I have a working, stock, oil pressure gauge with a simple adapter NOT sold by Summit for 500% mark-up. Don't get me wrong, Summit is awesome, but they don't have adapters to use for an Gen III/IV motor to a square body gauge setup using stock senders for manual gauges.

For Temp, I simply got the same kind of single piece adapter (looks just like all the ones from Summit etc but different size) and went from 3/8" for stock temp sender end to 1/4" to put in passenger side of head. Now I have a temp reading. Once I get the coolant back in tonight, I'll update on where my gauge reads hot since it's the original sender, but funny enough, it always ran a one third level with my 305 hot, so I'm gonna go on a limb and say it'll be near center.

I wrote this lengthy thread because I'm sure there will be other square body swappers wanting to use stock gauges and senders. I'll post pics of my adapters tonight or tomorrow. Good luck all.

Speedway.com sells the correct adapter for the water temp to go from the metric size in the LS head to 1/4 pipe like you need for your sender

[NC_John]

Originally Posted by LSSierra

So...I found a place called "FASTENAL" here local.......

I can't stand the local Fastenal store here. Bunch of kids working there that don't know which end of a screwdriver you hold. I went in there last week looking for a blind flange and they were acting like I was from outer space....

BUT, if you have the catalog and can find what you need, they do carry a lot of stuff.

[LSSierra]

Speedway does sell the same ones I got from Summit...problem is...unless I'm missing something here, is that the stock senders for manual gauges don't thread into the adapter because the male ends are too large and the adapters aren't long enough to grab the thread of the senders. I'll post pics tonight. Here is the link to what you are talking about correct?

http://www.speedwaymotors.com/Auto-M...Kit,66172.html

[mongocanfly]

That's probably the one..same one I got..only adapter fitting I could use for my mechanical gauges was the oil sender adapter bushing.it goes from metric to 1/8" npt.. that can be bought seperatly..my truck had idiot lights and I swapped over to mechanical...but I did have to drill and tap the pass head so the temp probe would fit..the ls head threaded hole was to small..but its no big deal to drill and tap.

[Houston Ben]

Look up glocks build. I used what he did and didn't have to tap/drill the existing hole.

[MalibuSSwagon]

Here's what I did for my swap.

Autometer 2268, is an adapter meant to replace the stock oil pressure sender behind the intake manifold. Adapts the metric threads in the block to 1/8" NPT and even has a sealing ring. $12 to $15 from the usual sources.

I turned down the OEM temp sender to 12mm x1.5 to fit the passenger side head. Just chucked up the sender in my hand drill and ran it over a flat file for awhile until it was the correct diameter. Then threaded it with a 12x1.5 dye and dropped a copper sealing washer on it. It's easy to do because it's brass.

Gauges work mint now. Make sure in your swap that you connect the ground from the firewall to the back of the head so your gauges read correctly! I had all sorts of funky gauge bouncing issues until I hooked up that strap.

[LSSierra]

My oil pressure gauge is good, temp is low but I just saw your thread and was going to check that ground tonight...good call. I connected all grounds but we all know how we "know" we did something.