Oil temp sender

[66 Käfer]

[Eric_S]

I use a stock T3 oil cooler with a bung on it for a sender. This way I can see the same oil temp that the bearings see. Fits in a dog house with minor mod.

[57 Rag]

I put (putting tomorrow) mine in the oil line with a T prior to the cooler. Yes yes I said prior. Earlier I was thinking of after the cooler to see what temp oil is going into the motor. CHanged my mind for the 3rd time.
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57 Ragtop
84x94 86C
IDAs

[fuscanet.com]

well i need your expertise then
im using megasquirt efi and a proper temp reading is needed.

now im starting to tune the ms i have put the sensor in the stock bulb place, but also bolted a brass piece next to sump (also have extra 1 1/2 sump) to hold the sensor later.

so my question is: is it really better to use near the sump?
how do you guys placed it? drilled the sump? or just by contact as i intend?

regards

[neil68]

I've also used the VDO relief valve sensor on several Beetles/Buses for many years. Very simple to install and allows for one wire to be kept tidy and out of the way of other hot parts such as exhaust:

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Neil.

Der Kleiner Rennwagens
68 Beetle 2332 cc, 204 WHP
12.5 seconds @ 107 mph
Dynojet Test: https://www.youtube.com/watch?v=M9B_H3eklAo

[fuscanet.com]

i really like your location there.
can u show me how big is the vdo sensor??

since i have gm coolant sensor and i think i will have to make a brass insert to use it

regards and thanks

[neil68]

That hex sender unit is actually a "single piece" just as you see in brass in the photo. Then just run a wire up to the gauge on the dashboard

Here's the correct part:

http://www.cip1.ca/ProductDetails.asp?ProductCode=VDO%2D323%2D064
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Neil.

Der Kleiner Rennwagens
68 Beetle 2332 cc, 204 WHP
12.5 seconds @ 107 mph
Dynojet Test: https://www.youtube.com/watch?v=M9B_H3eklAo

[Jimmy111]

That is really a bad place for it. The only time it will work is when your relief valve leaks. Then what is the point. The motor just overheats anyways
There is absoultly zero circulation of oil there.

[neil68]

The reading from the VDO relief sender actually is very accurate in my experience (similar temps to dipstick and sump senders when compared). I've been using them for over 20 years in many Beetles/Buses...with no overheated engines It also seems to jive perfectly with the thermostat operation as well.
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Neil.

Der Kleiner Rennwagens
68 Beetle 2332 cc, 204 WHP
12.5 seconds @ 107 mph
Dynojet Test: https://www.youtube.com/watch?v=M9B_H3eklAo

[fuscanet.com]

i will count on neil's experience but what about jimmys comments?
they sound reasonable, is there an explanation for how this sender at the relief location works ok?

what would be the problems for using it there?

thanks for your time

[neil68]

You will probably get arguments all over the place, recommending one method or another, such as tapping into the deep sump or the stock case or the oil pressure hole or the relief sender (like mine). I would say that once the engine warms up (over 180 degrees F), then the oil in and around the sump is pretty much the same temp, no matter where you locate the sender. Just pick a system and then get to know your engine. You can also just use the old dipstick test...if you can pull the dipstick after a 30-minute drive and still hold onto it continually without burning your hand, then you're probably okay for operating temp. Then, double-check it with your gauge reading, to get your comparison.

I think people get too carried away with monitoring temps and should just drive their Beetles...if they've got the stock doghouse cooling system, then they'll probably be fine
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Neil.

Der Kleiner Rennwagens
68 Beetle 2332 cc, 204 WHP
12.5 seconds @ 107 mph
Dynojet Test: https://www.youtube.com/watch?v=M9B_H3eklAo

[Jimmy111]

Hi Neil. Im not knocking you.
But think about it. Where does the oil come from to get into the base of the relief piston there??
Take a good look at the case and that area is completly seperated from the oil sump and any oil that is flowing at all. If your piston is leaking you can get some flow there thru the spring cavity and out the relief hole. But if you have a piston that is in good condition, then there will be no flow at all. You can remove the spring and piston, dunp the oil that is there and then drive aroung town and remove the plug again and most of the time, no oil will come out of the spring cavity again. The oil only gets sucked in little by little everytime the piston gets depressed and then reseats.
Try it and you will see what I mean.

[gerg]

I thought that without a super precision fit, at 30+ lbs constant pressure oil got past that piston to some degree.

I have one there and one in the sump. They run about 25 degrees apart (I pressume oil getting past the piston is cooler since it is return oil from the cooler).

They also climb at roughly the same rate as the engine warms up.

I am also not knocking anyone here, but mine seems to work well.
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Gerg

. . . I got 99 problems and my bus ain't one . . .

'65 Sunroof Beetle
'65 Vert
'60 Singlecab

[neil68]

That's my point...you just want a temperature that you know is a reflection of the crankcase temperature.

Maybe the VDO relief sender relies more on "radiated temp" than direct high-volume contact with oil, but my suggestion is that once the engine warms up, it doesn't matter...the temperature is still the crankcase (and oil) temperature.

Some people use a temperature detection gun on various parts of the crankcase to check temp (do a forum search) and they get various readings, but usually within 10-15 degrees variation. If they just pick the same spot, then they can still do comparisons under different driving conditions.

I guess I could contact VDO and ask them the theory behind this particular sender, but I don't think it matters.

Having been driven through Death Valley on a 100+ degrees F. July day, pulling a tent trailer in a '66 Beetle, I am amazed at the temperatures that the ACVW engine can tolerate
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Neil.

Der Kleiner Rennwagens
68 Beetle 2332 cc, 204 WHP
12.5 seconds @ 107 mph
Dynojet Test: https://www.youtube.com/watch?v=M9B_H3eklAo

[fuscanet.com]

well in my case, i will use the temps read for the warmup program of the MS ecu, so it will be interesting to have a good reading.

but if you say there are 15º between the best spot and the easier one, i wont brake my head, will use the easier one, the stock temp sender place.

thanks for your info, i found it very educating.

regards

[Bugmobeetle]

Hi, All:

I'm pretty new to Beetledom (just last year got my kinda ratty-but-runs-nicely '65 W/DP 1600 and Kadrons--kinda nifty) so my first post here will be a duh no-brainer to most if not all of you.

I got a temp sender designed for the forward pressure relief spot, but can't get the screw out.

So can I change my mind and use my new sender in the sump, or are the threads completely different.

If I hadn't just changed my oil I would try it and find out, but oil costs and I never put old oil back in my car once out (and exposed to grit and grim).

Let me thank all of you who post advice and opinions. This site has been a gold mine.

[ian c]

[TONYWILL1965]

in the sump,because the temp of the oil being pull up from there to bearings seems to be the most important,any heat pulled from the case is more than likely the temp of the oil,cause the oil is what made the case hot...i think?

[rossi46]

[disneymike]