roverdrive overdrive

I'm waiting on delivery of a laser thermometer, so I can get preliminary temps on all components, before I start installing temp gauges and coolers. I've got the Roverdrive with the finned sump.


My hypothesis is that after awhile the gearbox and transfer case will be running at the same temperature, as one will become a heatsink for the other. If that's the case, then it may be easier to install an oilcooler to the R380 and thus reduce the latent heat on the transfercase.

If heat is a problem, then this may be effective enough. Otherwise one may need to disengage the o/drive in extreme heat, much like one needs to back off the accelerator when EGTs get too high on a refuelled diesel.

Just thoughts at this stage, I'll post results as I get them.

Davo, can't find a duty cycle on these ?
http://www.earls.com.au/files/4af0e2...NSFERPUMPS.PDF
Available from Earls.

Other race suppliers would have similar.

One thing I didn't mention earlier and may make a difference is the radiated heat from the exhaust beside the g/box and t/case.

In my case the exhaust is wrapped from the dump to the crossmember and (subjectively) this reduced the temps radiating through the floor into the cabin.
It would stand to reason that if this did actually happen it would also allow the driveline to reject heat more easily and so run cooler, but I have no numbers to back this up.

I am looking at fitting my temp gauge for the roverdrive extra capacity t/case sump cover and am now wondering if there is any reason why it cant be fitted to the side of the t/case where the bung is now for a factory one?
I would be interested if there is any reason why not?

What models actually have a t/case temp sender fitted?

Any comments appreciated,

cheers,
Paul.

Quote:

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Originally Posted by rick130

Davo, can't find a duty cycle on these ?
http://www.earls.com.au/files/4af0e2...NSFERPUMPS.PDF
Available from Earls.

Other race suppliers would have similar.

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That's more like it! No duty cycle mentioned, but obviously meant for hard work. The only thing is that racing use is generally hard use for short periods while our use would be not so hard but for very long times. But those pumps could be worth looking into and, after all, if it failed then it's not like your car would stop instantly.

I don't think the radiant heat from exhausts or otherwise makes much difference to the Roverdrive. It's a compact little unit that does a lot of work and doesn't have a good way to throw off the heat it generates. And I'd bet that during intial testing in damp, soggy British Columbia they didn't realise this.

You can put a gauge sender wherever you want, but it has to be immersed in the oil, and obviously not going to be hit by any gears - get your brother-in-law or neighbour to stick his finger in the hole while you turn the rear driveshaft and wait for any screams. I think you're referring to the filler hole? That won't be low enough for the sender to be immersed. Can you put up a photo?

Quote:

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Originally Posted by Davo

That's more like it! No duty cycle mentioned, but obviously meant for hard work. The only thing is that racing use is generally hard use for short periods while our use would be not so hard but for very long times. But those pumps could be worth looking into and, after all, if it failed then it's not like your car would stop instantly.

I don't think the radiant heat from exhausts or otherwise makes much difference to the Roverdrive. It's a compact little unit that does a lot of work and doesn't have a good way to throw off the heat it generates. And I'd bet that during intial testing in damp, soggy British Columbia they didn't realise this.

You can put a gauge sender wherever you want, but it has to be immersed in the oil, and obviously not going to be hit by any gears - get your brother-in-law or neighbour to stick his finger in the hole while you turn the rear driveshaft and wait for any screams. I think you're referring to the filler hole? That won't be low enough for the sender to be immersed. Can you put up a photo?

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It is definitely a hole for the temp switch which is fitted to some lt230's.
The switch is set to about 145c and a light comes on the dash from what I have read. It looks like it is fitted to the D2 v8 discos.
The hole is a lot higher than the filler plug and some have actually overfilled the t/c using this hole.
I agree the sensor wont be fully immersed but how does the switch work? It is electric with wires by the look of the sensor for it.
Does the sensor on a mechanic temp gauge have to be fully immersed?
Hope someone knows, it might save me drilling and tapping the cover.:)

Cheers,
Paul.

Uninformed posted
I know it is a personal thing, but I cant understand why people by LR etc to tow 3+ tonnes. You would be much better off with a small Isuzu truck etc.

I could not agree more that a small truck would make a much better tow vehicle, but I am going to be spending 3 months towing a 3 ton van from Vic to the Northern Territory, and, after unhooking the van I do not wanted to be limited as to what I can see by the lack of a suitable 4 wheel drive vehicle .
When I bought my 130 ( 18 months ago)4 Wheel drive dual cabs that could legally tow more than three ton were few and far between. I did not want an F250 or a Chev.
There is never a perfect vehicle for every thing we want to do.

Davo posted
It would be nice to use a 12-volt oil pump but I can't find anything that has more than a 30-minute duty cycle. Using the existing drain and fill plugs as the inlet and outlet would be handy but the pump is the bit without the easy answer. But what a lot of trouble to protect a very expensive bolt-on.

Food for thought
I have a wood heater in my shed which also very efficiently heats the water in about a 20 gallon tank.
It does this by circulating the water from a small tank in the firebox to the larger tank by the "heat rises" principle ( I’m sure you have all seen it ). So I wonder if this can be applied in reverse to circulating hot oil from the transfer case through an oil cooler.
I believe this is how water was circulated through the radiator on early cars, before they were fitted with water pumps.
Dave

Yes, temperature gauge senders have to be in coolant to work. I've heard stories where people have lost their coolant and didn't know their engine was cooking as the gauge didn't move. (I haven't had personal experience of this . . . yet.) As for your transfer case, I can't say as I'm not familiar with these modern new-fangled motor cars.

Also, I've thought about an oil cooler that would be gravity or heat-powered but I've just got a feeling you wouldn't get the flow you'd need.

I remember there's a drain plug on my old Roverdrive - if someone's game they could take some oil flow off this and run it down through a cooler and then into the transfer case, but that's not an experiment you'd want to get wrong!

Quote:

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Originally Posted by Davo

Yes, temperature gauge senders have to be in coolant to work. I've heard stories where people have lost their coolant and didn't know their engine was cooking as the gauge didn't move. (I haven't had personal experience of this . . . yet.)

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I have x 2. Lucky for me it was both on work cars. Skewered my rad with a bit of U/G mesh flicked up by the front wheels U/G. Came to a sudden stop, gauge read normally. Second time was a pin hole crack in the rad plastic top and metal core and had been ejecting steam for the 90km trip home. I only noticed when I pulled up at home and steam was hissing out the front. Gauge read 50% to 75% (it was 39*C outside) so was not overly worried. Turned out I only had 2L of coolant left. Engine let go a week later. Low coolant alarms were fitted, but there not fool proof either....

...sorry I digress.

I have fitted the Roverdrive and the finned Roverdrive larger sump and taken a few short drives to compare transfer box oil temps.
The first drive was with only the sump fitted. and I drove about 40 Ks on an undulating road .
The air temperature was 18 - 19 C
oil temp 63 C.

Second drive was with The Roverdrive fitted and overdrive engaged. and the same road.
The air temperature was 27 - 28 C
Oil temp 75 C

Third drive was with the Roverdrive disengaged and again same road.
The air temp was 16 - 17 C
oil temp 64 - 65 C

Fourth drive I turned around and drove the same route again but this time with the Roverdrive engaged.
Air temp still 16 - 17 C
Oil temp 73 C

On first impressions I have a fair bit of gear whine which I had been told to expect until the new gear beds with the ones in the transfer case, This is mainly noticeable at lower speeds and seems to decrease as the oil gets warm. ( maybe I just get used to it )

The Defender now just lopes along at 100 kph 2000 RPM with only fraction of the noise I was getting in the cab.:D:D

It may just be an illusion but I do not think 1st overdrive is as high as 2nd with no overdrive as there does not seem to be any need to disengage the roverdrive when coming to a stop, the vehicle pulling away again quite easily even on a slight incline.
Dave :D:D

What oil are you using Dave ?