Not a restoration.

[bigbadbob76]

My sandwich plate arrived today so I've tapped one port to M10x1.0 and cleaned the thread on another port for the temp sender.
Also cleaned some of the anodising off the centre boss to ensure a good earth connection.
The sender is right in the flow and not quite touching the centre boss.
Will fit it tomorrow and see how well it works.






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[itchyfeet]

what sort of seal does that use?
you have to change the threaded tube to fit that Some are stuck tight.

[itchyfeet]

And are your references to having previously replaced a 22mm pump with a 30mm one correct?
in which case replacing my 26mm pump with a 30mm one won't make as much difference.

26mm not 22mm, don't think anybody makes a 22mm

https://www.vwheritage.com/type-25-bus/ ... oil-system" onclick="window.open(this.href);return false;

[Cobra88]

Changing to a 30 mm pump fixed my hot idle oil light flicker

Approx 15 psi boost to hot oil pressure on mine

[bigbadbob76]

what sort of seal does that use?
you have to change the threaded tube to fit that Some are stuck tight.

There's a D section O-ring between the sandwich and the case.
Cheers for the warning about some being stuck tight but I don't have to remove it, the plate comes with an extension adapter.
Ok about 26mm.

Changing to a 30 mm pump fixed my hot idle oil light flicker

Approx 15 psi boost to hot oil pressure on mine

Cheers Cobra, I'll take an extra Bar for £45
Refreshing the engine cured mine.

[Cobra88]

My engine was already refreshed but used a cheap pump.

So I thought I would try the 30mm jobbie before I ripped it out as "I can't remember who" did a thread about the tolerances on here

[bigbadbob76]

Sounds good Cobra.

I fitted my sandwich plate and sender tonight.


Took it for a spin and the oil temp came up nicely in synch with the coolant temp and settled with the needle vertical.
Ignore the actual gauge reading, that doesn't matter, vertical needle is "normal" for my setup.

Just for interest, i compared it to the sump temperature.




All good, no leaks or drastic pressure drop. Haha.
Drove home and checked again-




And a quick pressure check at 92*C






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[itchyfeet]

Cheers Cobra, I'll take an extra Bar for £45
Refreshing the engine cured mine.

I forgot they were so expensive got a one year old 2000 mile one I took out here going cheap if you are interested? ( bought a new one so I could O ring and swap without delay)
I'm unlikely to build another with a 4 rivet cam soon as they are NLA

[937carrera]

Do you think that looks a bit low BBB, even for 93 degrees. Remind us what oil are you using, still the 15W40 ?

[bigbadbob76]

Yes, still 15W40.
This was it previously at 80*C


so there seems to be quite a difference betweek 80C and 93C.
Hopefully that'll improve with the 15W50.
Interesting to see it settled at 93*C after about 6 miles and didn't get any hotter in the return 6 miles or in 10 mins idle after that, not as hot as I thought it was getting so I definately don't need an oil cooler.
I didn't do any motorway thrashing as the nearest motorway is 200 miles away but I did get it up to ermmm... speed... in order to do another test on a circuit that I'm working on.

got a one...... here going cheap if you are interested?

YES PLEASE paul!! I'll PM you.

[937carrera]

Yes, I too saw how significant an extra 5 degrees or so oil temp made to the oil pressure in that area, from what I saw about 0.2 bar for 5 degrees so the drop of about 0.6 bar seems approximately consistent with that.

Your oil pressures look very similar to mine on 20W50, but it looks as though if you were to have a 1.4 bar DOPS switch fitted you might be quite close to that going off in hot conditions.

With all the work you did on the rebuild I am expecting that you'll see noticeably better pressures on the 15W50, what oil filter are you using ?

[bigbadbob76]

That pressure was measured at the LP point, not on the sandwich where my 1.4 Bar dops switch is languishing waiting for a wire.
But based on your pressure tests at the HP point there's not much difference.
Hence why VW went to a 0.9bar switch I guess.
If the 15W50 oil lifts the pressure that should keep it above the DOPS pressure.
I'm going to try Pauls pump after I've changed to 15W50, one change at a time.
Filter is a MANN.

[937carrera]

Thanks for confirming the position you measured from, that's what I thought anyway.

As was stated earlier in the thread, I think VW went to the 0.9 bar switch because the 1.8 bar ones were going off too frequently and causing nuisance in the main dealers - probably particularly in hot weather conditions as you have demonstrated oil temps on 90+ are easily achievable which isn't the oil pressure spec temperature.

Glad you are doing one step at a time, and you have a MANN filter, that's the same as me. When I wanted one I tried SAS (same group as GSF) who are very near me and they tried to sell me the Mann manufactured second label version. I wasn't interested.

[bigbadbob76]

Also interesting is that fact that I checked the sender/gauge combination in boiling water before I fitted it and the needle was vertical at 98*C on my thermocouple.
So my thermocouple reads slightly low by a degree or two.
but does this also mean my oil temperature at the filter is actually closer to 100*C when the sump temperature is 92*C?
quite possible as it's straight off the pump which will warm it up by a few degrees.

[937carrera]

I believe measuring temperature of boiling water is actually quite difficult as the water isn't necessarily heated uniformly and you then have bubbles of steam ocurring too. As you said yourself, you are only looking for an indication of temperature, not a precision measurement. I wouldn't be worried about a couple of degrees, or the temperature at the filter being different to the sump, the oil will get warmer. Are you going to adjust the resistance to calibrate back to sump temperature on the gauge ?