TheSamba.com :: View topic - Oil temperature sender swap in place of oil pressure sender

Fri Mar 07, 2014 6:51 am

Curious if anyone knows if I would have the internal clearance within the case to use a oil temperature sender in place of the oil pressure sender. The picture is of the temp sensor I wish to use. As you can see, it extends farther than the pressure sender. I have converted the oil cooler on my 40 hp to the later dog house version. The oil cooler I am using has a port where I can relocate the oil pressure sender. I can't mount the oil temperature sender on this oil cooler since it will impede the flow of oil through portions of the oil cooler. I have some vintage Porsche 912 gauges I intend to use, and the oil temp gauge inclusion will be a big bonus. Any help will be greatly appreciated.

Fri Mar 07, 2014 10:53 am

I say if it screws in and doesn't leak you should be good, there is no fear of restricting the passageway since it dead ends up there anyway. Did u have to modify the shroud to get the sender in the cooler?

Fri Mar 07, 2014 11:00 am

Not really best place.... Anything that penetrates "port" beyond threaded area may block oil galley, and that would cause destruction of lower end because of lack of oil flow......

Best place for oil temp sender would be directly in main oil sump or fitting/device specifically designed to take oil temp sender ...

Dale

Fri Mar 07, 2014 11:11 am

keep in mind that the factory VW oil pressure sending unit was/is in a gallery that is not exposed to flow, only pressure. This will significantly delay/change your temperature readings.

Fri Mar 07, 2014 11:50 am

Thank you for the replies. Two good points made. 1) The stock port for oil pressure is at a dead end and not exposed to the flow of the oil. 2) This the main reason I asked. I don't want to block off any oil channels. I really don't want to disassemble the motor to drill and tap a hole in the sump, so I guess that leaves me with three options. 1) Dipstick oil temp sender. 2) Drain plug oil temp sender. 3) Make an extention out of aluminum or brass so that I can utilize the port on the oil cooler. Just need enough of an extention to compensate for the length of the probe. Will need to die a male 10 mm on the port end, and tap a female 10 mm on the sender end. I will need to modify a channel in the rear of the dog house for this to work. Will also need to plug this channel once installed.

Fri Mar 07, 2014 11:55 am

vugbug68 wrote: I say if it screws in and doesn't leak you should be good, there is no fear of restricting the passageway since it dead ends up there anyway. Did u have to modify the shroud to get the sender in the cooler?

It does not Dead end up there at the OP switch location. Here is a cut-away done by Jaycee Ent. to show the path.

Also I would not put it in that port because it will abstruct flow. There is an adapter that can be used to move it out. Here is the photo of what's on my engine for this purpose. Don't pay attention to the red arrow. That was another post about the restrictor plug I was discussing.

Fri Mar 07, 2014 12:05 pm

Like the cut away photo. Looks like you used the adapter for an oil pressure sender for a gauge. Any chance you remember where you got your adapter? I know I need 10 mm on the male end for this to work on the port of the oil cooler.

Fri Mar 07, 2014 12:23 pm

I also fed my turbo oil from this adapter. since it has an 1/8" NPT port coming out of it.
http://www.cbperformance.com/ProductDetails.asp?ProductCode=2355
Made by VDO

Fri Mar 07, 2014 1:22 pm

yamaducci wrote: vugbug68 wrote: I say if it screws in and doesn't leak you should be good, there is no fear of restricting the passageway since it dead ends up there anyway. Did u have to modify the shroud to get the sender in the cooler?

It does not Dead end up there at the OP switch location. Here is a cut-away done by Jaycee Ent. to show the path.

The location of the port is not in the flow of oil so blocking it would not restrict flow to the cooler, would it give an accurate oil temp? Probably not

Fri Mar 07, 2014 1:53 pm

The oil temp switch that is shown will protrude into the pressure sender port and into the flow of oil that is directly headed to the oil cooler. Now if you want the temp measured after the cooler going to the bearings then you may want a different location. As far as moving the sensor out a little bit with the adapter I listed above then it might be a few degrees cooler but lets face it; any analog gauge is just giving relative temp and not very precise. Since I run a turbo oiler out of that adapter port there is always a lot of post full-flow cooler oil passing the sensor to go to the turbos oil line. For that reason it may be a little bit more precise.

Fri Mar 07, 2014 2:12 pm

The port is a half inch to the right of the galley leading to the oil cooler.

Anyway, There is also a sender that replaces the relief screw, But I believe that 40 hp cases have a smaller relief plug and screw.

Fri Mar 07, 2014 2:33 pm

You're right. I see what you mean I would still measure to be sure it's where it needs to be.

Fri Mar 07, 2014 6:15 pm

The oil temp sender I am using replaces the drain plug.

Fri Mar 07, 2014 6:26 pm

You can get a T-adaptor that screws into the OG oil pressure sender location that allows you to run both the oil pressure light sender and a temp sender. It moves the sender outside the engine block, which isn't the most accurate place to monitor temperature, however...

Fri Mar 07, 2014 10:23 pm

why cant you use the oil relief temp sender ?
there is nothing to drill, just replace the relief plug cap with the sender

http://www2.cip1.com/ProductDetails.asp?ProductCode=VDO-323-064

Sat Mar 08, 2014 2:51 am

The relief plug sensor is great if your gauge is just bling, but there is almost no oil flow over it at that point so what it shows would be quite meaningless - even worse than the pressure light switch location. Best place is to tap the plug for the oil pickup - tons of room for oil to pass, and you have oil that has been averaged through the engine. Might not read as high or low as some locations, but it is about the most meaningful.

Sat Mar 08, 2014 4:16 am

Quokka42 wrote: The relief plug sensor is great if your gauge is just bling, but there is almost no oil flow over it at that point so what it shows would be quite meaningless - even worse than the pressure light switch location. Best place is to tap the plug for the oil pickup - tons of room for oil to pass, and you have oil that has been averaged through the engine. Might not read as high or low as some locations, but it is about the most meaningful.

This is the ideal place to do it if you are not setup for full flow.
And as Quokka42 stated about putting it at the oil pickup. I have done that Works well Just make sure that you are not blocking the oil passages. And exposing the sender helps too. I drilled out the adapter and tapped it to get the sender deeper into it.

Sat Mar 08, 2014 7:28 am

I don't think you could fit that to any full flow fittings without causing a restriction. I make my own sensors that are so small it isn't an issue and are much more accurate.

Sat Mar 08, 2014 8:06 am

Big IF here

IF one is using a universal case that
has the hole for the type 3 dipstick

drill and tap the block off plate
and install the oil temp sender at that location

Sat Mar 08, 2014 8:15 am

Mine is in the oil relief plug new the clutch. It does work and I will admit a lil slow to respond. For me it is a guide line of engine operation.