8V overcooling project

I would say a Temp Gauge of some sort is essential on any Oil Cooled Engine.
I can't imagine many people would be happy running a Water-Cooled Bike (or car) without a Temp Gauge, so why do we put up with it on an Oil Cooled Bike?

They're not too expensive, or difficult to fit.

temp gauge is indeed a good idea, see my previous post about my workshop being all crated up at present.. This is a temporary fix...

beetle wrote:

The ECU monitors engine temperature and intake air temperature. The only way to monitor the engine temp is via some sort of OBD tool. The only two that work with Guzzi are GuzziDiag and ScanM5X. ScanM5X is good because it's an Android app, and you can use a phone. Only works with the 5AM ECU.

The ambient air temperature sensor is part of the dash electronics. It only for rider use. It's not used in any way by the ECU. You can see it via OBD too. However, having it display engine temperature would require re-programming the dash and ECU software. Or a 3rd party dash.

The stock ETS isn't all that accurate, due to its location. Meaning, the measured temperature isn't necessarily the actual engine temp. The accuracy of the actual sensor isn't in question. I relocated mine because I could. The 1400 barrels have a better location. There's a resistance v temperature chart in the service manual.

I monitor the oil temperature coming from the sump to the cooler.


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Weeding through this interesting thread I noticed this post regarding scanM5X. If it's android based it could be usefull when applied to Carpuride display:
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I've been searching for a workable navigation solution and noticed this display mirroring the cellphone screen.

Since I am on a learning curve regarding this topic and understand a thermostat is recommended, is the temp gauge position described here for "research" or is this location good for a "consumer" shameless copy?
My GRiSO is at the mechanic right now nearing the completion of rollerise mod and have no good visual how to intergrate a thermostate in correct plumbing but Having 8K on the dash makes it still worth adding this item.

Thank you for highlighting this topic!

Kind regards, Erik

ErikdeBrabander wrote:

. . . is the temp gauge position described here for "research" or is this location good for a "consumer" shameless copy?
My GRiSO is at the mechanic right now nearing the completion of rollerise mod, and have no good visual how to integrate a thermostat in correct plumbing but Having 8K on the dash makes it still worth adding this item.

Thank you for highlighting this topic!

Kind regards, Erik

I would say the Sump is the best location for a Temp Sensor, that's where the bulk of the Oil is during running.
Having the Sensor in the Oil draining back down from the Heads would, I think, give a false view of Oil Temps.
It will be plenty hot enough at that point, but only for a few seconds, the Sump Temps could still be much lower than ideal.

As for the actual 'plumbing' of the Thermostat, I'd just copy Mark's set-up, all done with off-the-shelf parts as I recall.

As I've previously mentioned, I don't see any point in monitoring the actual engine temperature via the ECU. The location of the ETS combined with the ECU ADC and somewhat dubious voltage converter will never be pinpoint accurate.

The Carpuride would be great for Navigation, if you've got room for it. Using it with Scan5mx would provide some very interesting data like GPS speed, gear position, fuel consumption, throttle position, lambda, air pressure, and both intake and engine temperature.

As for oil temperature? Monitoring as it goes into the oil cooler would be best I think. I had it going into the cooler and out of the cooler, but that's just me being me.

Wow, 5yr anniversary on this and it hasn't blowed up yet, SUCCESS

Oh ye of little faith!

Why would it 'blow up' Steve, we're all sensible and mature adults here . . .  [You must be registered and logged in to see this image.]

Just a phrase as to nothing happened detrimental to the motor from adding the regulator. I was watching this when Beetle was installing on his bike. Not a naysayer, factory should have done this before production.

Ah, I thought you meant that this Topic/Thread hadn't blown up!  

It is sort of an Oil Thread after all . . .

beetle wrote:

As I've previously mentioned, I don't see any point in monitoring the actual engine temperature via the ECU. The location of the ETS combined with the ECU ADC and somewhat dubious voltage converter will never be pinpoint accurate.

The Carpuride would be great for Navigation, if you've got room for it. Using it with Scan5mx would provide some very interesting data like GPS speed, gear position, fuel consumption, throttle position, lambda, air pressure, and both intake and engine temperature.

As for oil temperature? Monitoring as it goes into the oil cooler would be best I think. I had it going into the cooler and out of the cooler, but that's just me being me.

I think I'll settle down with the Beeline Moto2 which will be available within a few days. Adding a temp display makes a challenge in front of the bike as well.

Correct me if I'm wrong, placing a sensor to the cooler shows the thermostat being activated, meaning the engine temp has been stabilised?
Would it still be worth considering shielding off a part of the cooler?
I'm still a bit puzzled regarding the sensor location and I'm wondering if placing the thermostat onto the cooler makes less couplings and a cheaper result.

kr, Erik

Trailtech do a nice temperature gauge, you'd need to check that the temperature range would work for oil temperatures.


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ErikdeBrabander wrote:

Correct me if I'm wrong, placing a sensor to the cooler shows the thermostat being activated, meaning the engine temp has been stabilised?
Would it still be worth considering shielding off a part of the cooler?
I'm still a bit puzzled regarding the sensor location and I'm wondering if placing the thermostat onto the cooler makes less couplings and a cheaper result.

Ideally you could have a sensor going into the heads and into the cooler, this monitoring both sides. I had that combo for a while, but since the temps were always in a good range and nothing outrageous occurred, I removed the gauges for less clutter in the dash area. I suggested placing one going into the cooler as there seems to be a desire for monitoring sump temperature.

There's no need to shield off part of the cooler once the thermostat is installed.

There's room for the thermostat under the cooler cover, but the fittings are too bulky to allow the cover to fit.

evansnows wrote:

Trailtech do a nice temperature gauge, you'd need to check that the temperature range would work for oil temperatures.


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The Trail Tech Gauges (I have one in my CARC Unit too) are what I've been using.
They're perfect for the job, Battery lasts 4-5 years.
I read somewhere that you could replace the Battery, but I couldn't get the Casing open on my first one without destroying it.
Maybe earlier versions weren't so well sealed.

Thx for your inputs .
IMO placing the sensor in the OUT line into the heads does show sump temp and one can see the thermostat actuated and eventually settled on the 103C seems more informative. And as you noticed, head temp is more of interest vs sump temp. Either way one choses, it is a luxury item not really needed when having a thermostat. Prefering the IN or to Cooler seems identical but doesn't indicate the temp to the head...

It took me quite a while to source a decent gauge. The Trailtech is not my favourite because of the batterie. I always prefer a wired option. (I'm not keen of batterie powered lights on my bicycles as well using classic ball bearing dynamo) .
Seems to match our wishlist well:
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This the temperature gauge I fitted to my bike, I machined the housing from billet and mounted the gauge using instrumentation rubber mounts, I drilled and tapped into the banjo fitting on the right head post oil cooler so you can see the oil temp before it goes into the engine, I also have a dip stick gauge and the delta T across the two can be up to 30 degrees C. The housing has now been painter satin black to match the bike.
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Nice Job MGV.

Quote :

. . . head temp is more of interest vs sump temp . . .

Not for me.
We all know these Engines are overcooled, that's the reason this topic exists.
The Oil running too cool is the reason we're fitting Thermostats.
I'm only interested really in the temperature of the 'bulk' of the Oil (i.e. in the Sump), as I don't want it retaining any moisture.

Interesting... Getting jumpy on a high DeltaT (highly fluctuating reading sensor to the heads) is somewhat distracting. Measuring the bulk seems valid as well.
To end my confusion, Beetles "to cooler" suggestion might be spot on a well and worth considering after I have gotten very keen on his recent mapping I experienced last weekend. It's easy to incorperate before going the thermostate route. Winter mods are too distant now.

Over the years I have bult many high performance VW engines, the last made over 200 HP on the dyno running 48 DRLA Dellortos, oil temperature is something I know about as in my job I monitored all the oil conditions onboard an FSO, I never run the oil hotter than 100C as it degrades above that temperature, I always measure the oil in my engines after the cooler and have a controller linked to the fans so it can be maintained below 100C before it enters the engine, Pete tells me there is no cooling for the oil in the sump and this could be a problem as I have seen 115C in the sump while the oil after the cooler was 80C, in reality, I would like to see an oil temp of a maximum across the board of 100C as that is hot enough to get rid of the nasties and not to hot enough to change the structure of the oil.

Doc. wrote:

Nice Job MGV.

Quote :

. . . head temp is more of interest vs sump temp . . .

Not for me.
We all know these Engines are overcooled, that's the reason this topic exists.
The Oil running too cool is the reason we're fitting Thermostats.
I'm only interested really in the temperature of the 'bulk' of the Oil (i.e. in the Sump), as I don't want it retaining any moisture.

beetle wrote:

It's not the sump oil temperature that's the issue. Oil is pumped directly from the cooler heat exchanger to the heads. This is where the issue lies.

The oil in the sump has been heated by the heads and cylinders, and can be as hot as 130 degrees. What we are trying to do is keep the oil that's pumped into the heads at around 100 degrees.

Weeding through this thread again after MGVirgin post.
Beetle post shows a DeltaT=30C With an intended Tsump=100C  to prevent sludge in the heads with FSC-215 thermostat.

A little googling showed Engine oil temp is best at 110-126C. I assume this is head temp.
Thermostat FSC-205 ,slightly colder as Beetle tested (stabilisatoin205ºF (96ºC), activation200ºF (93ºC), full flow221ºF (105ºC)) would give the max head temp 126C thus the average head temp 111C which is still hot enough to prevent sludge without breaking down the oil.


Now after the test results Beetle made, could we prefer a slightly colder 96C thermostat or even a 85C version would be best?
The 85C and 96C version would still vapour moist in the head and clean the sump of moist as well.

I also noticed locally, most thermostats are 82C for a reason which is food for thoughts IMO.
The thermostat brand Beetle used isn't locally available which adds additional S+H and custom fees.
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kr, Erik

I have been doing this since I was 21 and in my job as a senior mechanical technician offshore, I was involved in oil analysis and the management of all the associated machinery, if the oil remains under the 100C in the sump, it is hot enough for the nasties to be removed though the oil vapor and not hot enough to reduce the life of the oil, After fitting the gauges, I am beginning to believe the cooler oil temp going to the heads is not an issue as the temp in the sump can get too hot to do its job and is not managed, the heat is generated by the friction of the crankshaft bearings, the bore and the returning oil from the heads, I have no idea who thought it was a good idea to only cool the oil going to the heads which is quite effective. Every high performance VW engine I have built has a full flow system with a larger pump, thermostat, filter, cooler with fans with a goal of maintaining 90C so the oil lasts at least 5000KLM as oil deteriorates in service after that amount of miles and was borne out by the oil testing we used to do as we changed oil on condition, not hours or kilometers, I would never in my wildest dreams just cool the oil going to the heads, it makes no sense as the oil is the life blood of an air/oil cooled engine and I have seen 120C in the sump on one occasion and have been pondering on how to fix the elephant in the room.

As soon as there's a hint of rain or a wet road the sump temperature plummets. I actually prefer to keep the temperature above 100*C simply to make sure all the moisture sublimes off. With a modern full ester synthetic multigrade there is no concern about the oil degrading as they will function perfectly well at way higher temperatures for way longer than oils of yore.

Really though I don't think the lack of a stat is a tremendous concern unless you live and ride somewhere constantly cold and damp. I've yet to see an 8V that has failed due to oil degradation or water contamination.

Stop overthinking it.

If this "I've had more Sunday dinners than you" bullshit keeps up, I'll lock this thread.

Valid reason to install a temp Gauge and experience what is happening on my personal favourite weather conditions and enjoy summer first before tinkering[You must be registered and logged in to see this image.]

As Pete wrote I'm under the impression that the modern fully synthetic oils will handle high temperatures.
Considering the temperatures created in turbo and supercharged motors I can't see that not being the case.
Personally when I was considering where to place the temperature probe. I felt tapping a hole in the sump plug and having a bullet connection to disconnect the sensor when removing the sump plug for oil changes seemed the simplest solution and easily remedied if not felt necessary.
I decided to do without the gauge and fit a thermostat. New Zealand fitting Petes cold and damp conditions often.