Retroanaconda Posted January 19, 2012 Share Posted January 19, 2012 When my 110 goes back together, it's going to be housing a Mazda SL35Ti engine. According to the workshop manual I've acquired for this lump, it has an water-oil engine oil cooler built on to the side of the block (similar to the Td5). This is all well and good, but it does mean that my radiator's oil cooler (as used by the previous 200Tdi) is now defunct. (the engine also appears to have an engine oil lubricated injection pump and vacuum pump, which strikes me as a good idea!) I know that I could get a different radiator that doesn't include the cooler, or I could just blank off the ports. However, I wanted to fit an oil cooler to the R380 gearbox that I'm planning to fit to help it cope with the extra torque of the Mazda engine. What I'm wondering is, what is the construction of the radiator-mounted oil cooler that my 200Tdi rad includes? And would it be suitable for pumping MTF94 through in order to help keep the gearbox oil temperature in check? Any thoughts much appreciated, cooling is one of my main issues with this build plan. Got to find room for engine radiator, gearbox oil cooler, intercooler and air conditioning condenser! Hence if I could combine the first two it would save me some space! Quote Link to comment Share on other sites More sharing options...
minimaquinas Posted January 19, 2012 Share Posted January 19, 2012 hi would you need a pump to pump the oil around the rad as the rad will be higher than the gearbox just a thought brian Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 19, 2012 Share Posted January 19, 2012 The R380 has a built in pump IIRC. I see no reason why not to do this, it should have enough flow as the ports are roughly the same size as the R380 ports, and it's nothing more than a tube in the end of the rad, iIIRC. Bonus is you will get quicker warm up time as well as the cooling effect, as the water will warm faster than oil, meaning smoother changes earlier. As anything you do will be an improvement to the current gearbox cooling, and behind a V8 or TD5 they are OK, the extra torque shouldn't be a problem... how much extra torque we talking about....? Can't see a downside TBH Quote Link to comment Share on other sites More sharing options...
Ex Member Posted January 19, 2012 Share Posted January 19, 2012 Is it really a good idea to heat up the gearbox oil? Under the condition the cooling is needed, the radiator would be hot and the "cooling" for the gearbox would be in hot coolant. I think an air cooler is a better choice. Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted January 19, 2012 Author Share Posted January 19, 2012 hi would you need a pump to pump the oil around the rad as the rad will be higher than the gearbox just a thought brian Yes, I was planning on using the standard R380 pump housing which bolts to the side of the gearbox if I recall correctly. The R380 has a built in pump IIRC. I see no reason why not to do this, it should have enough flow as the ports are roughly the same size as the R380 ports, and it's nothing more than a tube in the end of the rad, iIIRC. Bonus is you will get quicker warm up time as well as the cooling effect, as the water will warm faster than oil, meaning smoother changes earlier. As anything you do will be an improvement to the current gearbox cooling, and behind a V8 or TD5 they are OK, the extra torque shouldn't be a problem... how much extra torque we talking about....? Can't see a downside TBH The engine puts out 277 pounds-feet of torque, so a bit more than a standard Td5, but there are plenty of tuned versions of those kicking about without blowing up gearboxes. It works out as 375 Newton-metres, so just about under the 380Nm the R380 was reputably rated for Red90: That's a valid point. Assuming the engine working temperature is about 90 degrees, as long as the gearbox oil's working temperature is higher than that then passing the oil through the cooler will have a beneficial effect. If course if the gearbox oil operates at 60 degrees then it'll be no good. I would think the oil pump housing adaptor for the R380 would have a thermostat in it. Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted January 19, 2012 Author Share Posted January 19, 2012 Okay, a bit off Googling turned up this post on AULRO. The chap states: searching for something else and dug this one up from the archives.....Interesting quote from LRA (Land Rover Australia) The operating temperature of the R380 box and/or transfere case on a 1998 Disco 300TDi 5speed is approximately 72 degrees C. I've been concerned about operating temps in summer (35*+) of my gearbox when I had the gear oil start to thin excessively resulting in reduced shift quality. My Defender doesn't have a gearbox oil cooler, like early 300Tdi's had, or TD5's have. I obtained the bolt on oil cooler adapter and pipes from Triumph Rover Spares in SA which came off an early 300Tdi, and pulled apart the thermostat to check it. It was rated at 86* or 87*, which I checked in a pot on the stove (shhh, don't tell SWMBO :wink: ) No, I haven't fitted it yet. I think this gives an indication how hard your gearbox works. Perhaps this puts the idea out of the window, since the cooling medium (the water in the radiator) might be - at least in part - at a higher temperature than that of the oil being cooled. Is the oil cooler within the main radiator designed to do it's job via water-oil or air-oil cooling? Ie. is it the cooled engine coolant or the airflow that does the cooling? Quote Link to comment Share on other sites More sharing options...
Tanuki Posted January 19, 2012 Share Posted January 19, 2012 Is it really a good idea to heat up the gearbox oil? Under the condition the cooling is needed, the radiator would be hot and the "cooling" for the gearbox would be in hot coolant. I think an air cooler is a better choice. Putting the transmission oil through an oil-water heat-exchanger in the bottom tank of the radiator is SOP for a whole lot of current-generation automatic gearboxes. It makes sense too for a manual-box if you really feel it needs a cooler. Though whether you're doing a transmission-oil/coolant heat-exchanger or an oil/air one I'd want to put an in-line thermostat in the transmission-oil pipework so the transmission-cooler doesn't become active until the oil's above 100 Centigrade. Modern engine/transmission systems usually combine engine-coolant, engine-oil and transmission-oil heat-exchangers - the primary heat-dissipator being the coolant-radiator. The object is to exchange heat and bring bulk engine- and transmission-oils to the ideal temperature (85-150 Centigrade) before you start dumping any heat from the coolant. In the case of an automatic transmission, this can involve deliberately raising the road-speeds at which gearchanges happen, in order to get more heat into the system. Some won't allow torque-converter lockup to happen until everything's hot. A side-effect of this is that since the system is seeking to get the engine/transmission to its optimum working-temperature as fast as possible, the cabin-heater is bypassed. Hence the likes of Eberspacher cabin-heaters to cover the gap between cold-startup and 'the system' having any heat that can be spared to warm the driver. --Tanuki. Paranoid? Is that what they're saying about me now? Quote Link to comment Share on other sites More sharing options...
Tanuki Posted January 19, 2012 Share Posted January 19, 2012 Okay, a bit off Googling turned up this post on AULRO. The chap states: Perhaps this puts the idea out of the window, since the cooling medium (the water in the radiator) might be - at least in part - at a higher temperature than that of the oil being cooled. Is the oil cooler within the main radiator designed to do it's job via water-oil or air-oil cooling? Ie. is it the cooled engine coolant or the airflow that does the cooling? The radiator oil-cooler is in the bottom of the radiator: so if your radiator is within capacity, it will still be providing cooling to the transmission. Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted January 19, 2012 Author Share Posted January 19, 2012 That's good news. I think it can only provide a benefit, since the thermostat in the gearbox oil cooler adaptor plate would prevent it heating up the oil further than spec! Definitely going to be fitting the transmission oil temperature warning light though Quote Link to comment Share on other sites More sharing options...
rick Posted January 19, 2012 Share Posted January 19, 2012 Is it really a good idea to heat up the gearbox oil? Under the condition the cooling is needed, the radiator would be hot and the "cooling" for the gearbox would be in hot coolant. I think an air cooler is a better choice. John, the crack temp for the radiator and engine t/stats are 74*C (IIRC they use thesame t/stat) but I agree, I'd rather use a dedicated air/fluid cooler. Quote Link to comment Share on other sites More sharing options...
rick Posted January 19, 2012 Share Posted January 19, 2012 Putting the transmission oil through an oil-water heat-exchanger in the bottom tank of the radiator is SOP for a whole lot of current-generation automatic gearboxes. It makes sense too for a manual-box if you really feel it needs a cooler. Though whether you're doing a transmission-oil/coolant heat-exchanger or an oil/air one I'd want to put an in-line thermostat in the transmission-oil pipework so the transmission-cooler doesn't become active until the oil's above 100 Centigrade. Modern engine/transmission systems usually combine engine-coolant, engine-oil and transmission-oil heat-exchangers - the primary heat-dissipator being the coolant-radiator. The object is to exchange heat and bring bulk engine- and transmission-oils to the ideal temperature (85-150 Centigrade) before you start dumping any heat from the coolant. In the case of an automatic transmission, this can involve deliberately raising the road-speeds at which gearchanges happen, in order to get more heat into the system. Some won't allow torque-converter lockup to happen until everything's hot. A side-effect of this is that since the system is seeking to get the engine/transmission to its optimum working-temperature as fast as possible, the cabin-heater is bypassed. Hence the likes of Eberspacher cabin-heaters to cover the gap between cold-startup and 'the system' having any heat that can be spared to warm the driver. --Tanuki. Paranoid? Is that what they're saying about me now? The R380 cooler plate has a t/stat inside it that, as I mentioned in the above post, cracks at 74*C. It's standard fitment outside the EU for TD5's. I've run tests on a non cooled Tdi 'K' spec R380 and it hit 75*+ in about 7km of highway running @ 100km/h. Auto tranny's run quite a bit hotter than a manual gearbox, once the fluid gets hot shifting goes to hell IME and obviously gear rattle and noise increases. (35*+ ambients, high load/speeds) Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted January 19, 2012 Author Share Posted January 19, 2012 Well I reckon it's worth a shot. I can always put a temperature sensor in to check the operation of the system in the early days. The vehicle may well be expected to do long journeys in hot climates, so it will pay to be sure. Worst case scenario I'll put a small oil cooler in there, but it would be mighty handy if this is a viable solution, all I've got to do then is find a home for the air con condenser that isn't in front of the rad/intercooler and job done! Quote Link to comment Share on other sites More sharing options...
Howitzer Posted January 20, 2012 Share Posted January 20, 2012 I only have experience of the LT77 but what will regulate how much oil is inside the gearbox? If your oil cooler rad is higher than the fill plug on the gearbox would this not mean you will have too much oil in the box ? If you filled the gearbox in the standard way (Presuming you do it the same way as the LT77) then when you start the engine your gearbox will be low on fluid as most of it is in the radiator? Or when you stop the car with the gearbox hot, the stat will be open and the oil will drain back into the gearbox overfilling it and until the stat opens again the box will be overfilled and running. Dave! Quote Link to comment Share on other sites More sharing options...
reb78 Posted January 20, 2012 Share Posted January 20, 2012 I think thats a good point ^^^^^^^^ re height of the cooler relative to the box. What height are normal gearbox oil coolers set at relative to the box? Are they the radiators that you occasionally see mounted beneath the height of the front bumper? Also, i think someone mentioned that the thermostat would protect from overheating earlier - that wouldnt be the case since the stat will just stay open beyond the temperature at which it is meant to open. Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted January 20, 2012 Author Share Posted January 20, 2012 I'll have a look at my radiator assembly this afternoon and see what sort of height the cooler is at. At the bottom according to a post above, but one of the pipes goes in at a reasonable height. Bear in mind that it's a sealed system though, so the oil would only be able to drain back if it was vented to allow air in behind it. Otherwise you'd just get a vacuum. Quote Link to comment Share on other sites More sharing options...
tacr2man Posted January 20, 2012 Share Posted January 20, 2012 Once the system has cycled at least once you would need to recheck your oil level in G/box , but after that it should stay same whether cooler is operative or not , as mentioned previous with stat shut the oil in system isnt going anywhere ( same as using mil oil cooler on series diesel) , if you were really worried you could just make return pipe have a loop in it to stop a slight siphon effect . BTW I found Redline synthetic gear oil to be A1 out in Australia in 130 300tdi DCHCPU esp when running at GTW 7450KG in 40C HTSH Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 20, 2012 Share Posted January 20, 2012 There may be a non-return valve in the pump housing, or in the pump itself! Quote Link to comment Share on other sites More sharing options...
tacr2man Posted January 20, 2012 Share Posted January 20, 2012 Why not put aircon condensor on roof , saves pumping heat into airflow for rad , which is last thing you need when in hot conditions , this would do the trick http://www.rdac.com/sites/default/files/catalog/Ecat/Condensers.pdf I have my whole unit on roof Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted January 20, 2012 Author Share Posted January 20, 2012 I did consider that tacr2man, I have seen your setup and it looks very well done. However I want the vehicle to look reasonably standard, and even the lowest profile units would stick out a goof 6-7" from the roof line. Your vehicle has a roof rack that hides it well, but I'd rather not put anything permanently on top of mine - it will be high enough as it is! This is the radiator assembly as viewed from the engine's point of view. I will be swapping the rad and inter cooler round right-to-left, but they will stay the same way up obviously. Anyone familiar with what the pipes actually do inside the rad? Or do they literally just join up in the end coolant tank there? Quote Link to comment Share on other sites More sharing options...
mmgemini Posted January 20, 2012 Share Posted January 20, 2012 Yes I've seen insde the tank of the rad. All that's in there is a pipe with a 90 deg connection for the heat exchanger pipes from the engine.... There's an oil thermostat in the heat exchanger pips near the oil filter. Nothing inside the pipe in the radiator.I'm lucky. I could ask at my radiator specialist to see the radiator being stripped. The heat exchanger is in the right tank of the radiator. In the left hand tank, depending on the model specification there could be restrictors fitted. I just use a normal air to oil cooler on my Defender for gearbox cooling.... The transfer box area runs cooler with an X-Brake handbrake fitted. Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted January 20, 2012 Author Share Posted January 20, 2012 Thanks for that Mike. To clarify, you say there is a heat exchanger for the oil in the tank to the right. That is a water-immersed one correct? As in, it's a water-to-oil cooler rather than an air-to-oil cooler? Got an X-brake, prototype one too...though I'm not sure that would affect heat dissipation through airflow Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 20, 2012 Share Posted January 20, 2012 It would be worth looking at the RoW spec coolers I guess, see where they are mounted, to rule out the height being an issue. I don't know of anyone running one so can't contribute on this Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted January 20, 2012 Author Share Posted January 20, 2012 This is the ROW-spec cooler for the 2.8L Petrol (South African?) Defenders. Normal ROW-spec Defenders just had a loop of pipe to the engine bay and back, no cooler at all - just relying on the pipe itself. It's quite a slimline unit, the cooler, I reckon it might fit under the radiator behind the front panel. Where Td5s have all the perforated holes. Only problem is that this was the one place I could think to fit my air-con condenser, hence the above question about combining the gearbox oil cooler into the rad! Guess I could phone Ashcrofts and see if they have an opinion, I can't be the first person to have thought of this. Quote Link to comment Share on other sites More sharing options...
mmgemini Posted January 20, 2012 Share Posted January 20, 2012 Retroanaconda PM to you Quote Link to comment Share on other sites More sharing options...
TSD Posted January 20, 2012 Share Posted January 20, 2012 I have a tell tale label on the casing of my R380, thats been there since I fitted the gearbox. Despite a lot of high speed motorway work behind a TGV, it's never gone over 85 degrees in 3 years or so. In places like SA, where the ambient temperatures might be 20 degrees hotter, that would push the oil temps more than 20C higher, and I'd consider a cooler might be a good idea. In the UK, the only benefit I could see would be that possibly the oil gets warmed to a better operating temperature. The downside is the small additional risk of failure due to accidental oil loss. Quote Link to comment Share on other sites More sharing options...
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