Temp and oil sender locations for LS engines

[sambo]

With the engine loom on the way, I need to decide on locations for the oil and temp senders for my gauges. The factory senders go to the ECU and in a Commodore the signal is forwarded to the gauges, but my VDO gauges don't work that way.

For the oil sender, perhaps tap a thread into the block just above the oil filter? It has been suggested that the temp sender be fitted into a metal sleeve inserted into the lower radiator hose.

Just wondering what path other LS Cobra owners have taken. Of course any pictures would be a great help.

Cheers

Sambo

[Tenrocca]

Sambo - My temp sendor is plugged into the header tank - Got a bung welded in when I had it built- probably not ideal but OK once water is circulating. Oil pressure I have a sandwhich plate for the remote filter and oil cooler which had an extra port that I put the sensor into. I have heard of tapping into the domed bit just above where the filter screws in. Think saw that in LS1tech.com - do a little search on there and Im sure you can find a pic.

Cheers

[sambo]

Thanks Andrew. I found out that "domed but" is called an OFAC (oil filter adapter cap) and an aftermarket shop has a PDF showing how to tap it for their sender.

SCSS Oil Pressure Sender PDF

Otherwise something premade like this, although freight from the States will be the greater cost!

LS1 LS2 LS6 Oil Pan Routing Block Off Plate Threaded

[stiffy]

SAMBO,


I got my gauges from Howard's and they came with the adapters.

My water is in the header tank and I think the oil is in the pan you sourced for me.


Hope it helps,,,,


STIFFY

[sambo]

Thanks Stiffy. Same gauges/senders as mine and I have the same pan, so do you know where the oil pressure sender is mounted in the pan? You mentioned adapters but did you mean senders? The water and oil ones are very similar except for a white or yellow bead around the top (oil is the yellow one).

[CHANMADD]

The temp guage (coolant) should be in the intake manifold just before the thermostat, or in the thermostat housing.
The Oil pressureguage should be on the side of the block closest to the oil pump location. the pressure sensor has to be in the oil passage just after the pump.
John

[sambo]

Thanks John. The LS (Chev) thermostat housing hangs off the water pump and it's a little difficult to get the temp sender in there. I guess what you're suggesting is that if the thermostat fails to open and the sender is in the radiator hose, it won't see the motor boiling?

[Tenrocca]

Sambo, In that scenario you will get a check engine light as a backup.

Cheers

[Gav]

I have my oil pressure pick up just above the oil filter, and drilled and tapped an 1/8" port into the underside of the water pump 50mm back from the thermostat housing.
Works well thus far.

[Aussie Mike]

Hi Paul,

Temp sensor locations are easy on the LS motor.

The factory coolant temp sensor is in the front of the passengers side head just next to the exhaust flange. If you check the back of the drivers side cylinder head there is a corresponding hole with bung threaded into it. This has a 12mm thread and you can make an adapter to take it down to 1/8 NPT or BSP depending on the sender you are using.

I'm using mechanical gauges and the temp senders have a capilary tube with a bulb on the end. This required a bit of messing round to get them into the LS motor but it's do-able. Here's the back of the drivers cylinder head where I've drilled out that 12mm hole and re tapped it larger to take a larger adapter I made. A M12 to 1/8" NPT wouldn't just screw straight in without the extra work. You get the idea. I made one for Phil Neall some time back.


Oil pressure is easy too. There is a crossover above the oil filter where oil is ducted out of the sump and back in again. I reckon it is an adaptor for an oil cooler. It already has a boss cast into it that can be drilled and tapped to 1/8" NPT. I used mine with an AN#3 adapter so I could run a braided line back to the mechanical gauge. An electric sender could be threaded in just as easily.



Oil temp is easy depending on which motor you have. If you have a US crate motor it is likely the sump is already drilled and tapped for an oil heater. In extreme cold temps there is an option to plug your car into an electrical outlet and keep the oil in the sump warm overninght in freezing temps. I just unscrewed this heater and made an adapter to take my mechanical oil temp sender.



If it's an Aussie motor it may still have the boss in the casting. Otherwise the sump is plenty thick enough to drill and tap a hole directly into it. I would take the sump off to do it but even that is an easy job due to the reusable O-ring gaskets.

Hope this helps.

Cheers

[boxhead]

Sambo, sorry for not having better pictures but I found these 2.
This first picture is where I located my Water temp sender, I drilled and tapped a hole straight into the top section here.


And for my oil pressure gauge I drilled and tapped a thread into this part of the oil filter adaptor, I think if you run an external cooler you could use this fitting.


Mike beat me to it, I wanted to fit my temp sender in Mikes location but the adaptor I made did not have enough meat in it and it split when tried to tighten it up.
And I wanted to get it working that day and had no access to a lathe so I just drilled and tapped where I circled in above pic.
The oil pressure switch is in the same loaction as Mikes.

[sambo]

Thanks guys, the photos really help. I changed over to the LS2/corvette sump so I can put the oil temp sender in place of the oil heater. From memory the heater is a plastic gadget inside the sump so it will have to come off.

Is there a gasket behind the oil crossover thingy? I plan taking it off to tap it properly.

Andrew - do you know what temp triggers the MIL to come on? I guess I prefer to see it steadily rise than having it come on suddenly in heavy traffic.

[Aussie Mike]

The sump heater just unscrews. I think it has a large metric fine thread 18 or 20mm.

There is an O-Ring behind the oil crossover.

Cheers

[gjkrv8]

Hi Paul,

I put the Oil Temp and presser senders on an Oil Filter Sandwich Plate which had 1/8 NPT holes in it. (found it hard to find one with 13/16 UNC Oil Filter thread though - had to combine two - long story)

Water Temp was using a 1/8 NPT to 12 mm adapter into the drivers side head, which has a bung in it.

Be careful with the adaptor though as Boxhead said there's not much meat left on it. I broke the first one and had to get an Esayout to get it out. Replaced it very gently and used locktite. Doesnt leak.

Rgds

Gregg

[sambo]

Thanks guys. I need to scrub up on all this NPT stuff and practice my thread tapping before I tackle this job.

[boxhead]

I just noticed in the pics for the oil pressure sender, Mike's pic has the Corvette sump (Oil reservoir at rear) and mine is the Holden (Oil reservoir at front).
So Mikes filter and housing is at the L/H rear of engine and mine is at L/H front of engine, so it will depend on where your reservoir is but my sender is just below the alternator.

[sambo]

Yeah mine's the same as Mike's so I'll go off those pics. Cheers.

[Aussie Mike]

NPT = National Pipe Thread
BSP = British Standard Pipe

The 1/8" actually refers to the bore of the pipe. The fitting itself is probably closer to 7/16" in diameter.

Taper threads are designed so that the deeper the fitting is screwed in the tighter it gets (Stiffy will have fun with that one) The idea is that the fitting forcing itself into the sides of the threaded hole makes for a better seal. Especially when combined with some thread sealer.

You will find the fitting is slightly tapered and the tap for threading the hole is tapered too. You have to be careful when running the tap in to make a thread that the fitting will seat to the right depth. It takes a bit of practice and a bit of trial fitting to get it right.

I've got both NPT and BSP taps and you are welcome to borrow them. Pop over one weekend and I'll show you how to use them too.

Cheers

[sambo]

Fantastic offer, thanks Mike. Could you PM me your mobile number please? Meanwhile I'll try to work out what tap is needed for my senders.

[Beejay]

I just put a spacer under the existing oil pressure switch at the back of the engine.

Really easy and neat if you have the right tools.

My coolant temp is the same place as Mike.

Ben