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Re: Not a restoration.
Posted: 07 Aug 2018, 22:49
by 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.
Re: Not a restoration.
Posted: 08 Aug 2018, 09:28
by 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.
Re: Not a restoration.
Posted: 08 Aug 2018, 10:32
by 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 ?
Re: Not a restoration.
Posted: 08 Aug 2018, 11:41
by itchyfeet
bigbadbob76 wrote:
itchyfeet wrote: got a one...... here going cheap if you are interested?
YES PLEASE paul!! I'll PM you.

As discussed the old memory has faded and it's a new pump that I oringed with minimal compression so that the oil channels didn't cut the ring but I was not entirely happy with it so I cut the old pump in the end with more compression on the oring.
Not doing any good in my shed so as you are prepared to spend sevewral hours fitting it to see if this works it's on me, it would be good to know for future ref.
20180808_080040 by
Paul_Barr, on Flickr
Re: Not a restoration.
Posted: 08 Aug 2018, 13:16
by bigbadbob76
Thanks Paul.
A free pump already o-ringed!!! you don't get an offer like that every day.
Very kind of you and It's worth the fitting time to see if it helps and I'm more than happy to be the guinea pig to test the deeper groove.
When fitting piston seal O-rings in underwater housings I never make them so tight that you have to hammer the piston in, just a firm shove is fine for 100M+ H2O.
So I'm pretty confident it will seal.
Re: Not a restoration.
Posted: 08 Aug 2018, 13:37
by itchyfeet
bigbadbob76 wrote:
So I'm pretty confident it will seal.
wait until you get it and decide its not a firm shove more of an easy push fit.
Re: Not a restoration.
Posted: 08 Aug 2018, 14:24
by bigbadbob76
Still better than an easy slide without the o-ring though?
Re: Not a restoration.
Posted: 08 Aug 2018, 17:36
by itchyfeet
Don't fit the o ring on it, it's been into a case and out again so probably scuffed.
Hopefully you will get an extra Bar from a Barr

Re: Not a restoration.
Posted: 08 Aug 2018, 19:42
by bigbadbob76
Cheers Paul. That would be spiffing.
Oil n filter change tonight.
15W50 fuchs titan mineral.
That's good.
Up 1/2 Bar on the 15W40.
And ties in with Pauls findings.
Sent from my iPhone using Tapatalk
Re: Not a restoration.
Posted: 08 Aug 2018, 19:52
by 937carrera
What's that 2.8 bar at 80 deg C @ 2000 rpm. Compares to my 2.2-2.5 bar readings for comparable conditions.
Looks like you will be able to fit a white 1.8 bar DOPS pressure switch and have silence, I'm delighted for you.
Re: Not a restoration.
Posted: 08 Aug 2018, 20:04
by bigbadbob76
I'm delighted too, and with Pauls pump I'll be blowing the seals out.
I forgot to check the cheapo gauge at 80*C but I won't re-calibrate it, vertical needle is normal, that's good for a quick glance check without actually reading the gauge.

Not a restoration.
Posted: 09 Aug 2018, 14:14
by bigbadbob76
Pump came today. Thanks Paul.
That'll keep me busy at the weekend.

Re: Not a restoration.
Posted: 09 Aug 2018, 21:12
by bigbadbob76
I did some hot runs tonight and got the oil temp gauge into the red.
Did a thermocouple check when I got back-

Re: Not a restoration.
Posted: 10 Aug 2018, 08:12
by RogerT
“Hot runs”? Too much vindaloo?
Seriously though, is that achieved by thrashing it up a hill, or are you just reliant on your buses exemplary handling and brakes, and a lack of speed cameras in Skye?
Re: Not a restoration.
Posted: 10 Aug 2018, 12:14
by bigbadbob76
Better than that Roger.....From my other thread-
bigbadbob76 wrote:Well THAT was fun....
I got on the airstrip for a few quick sprints. (friends in high places)

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