Hybrid_From_Hell Posted January 28, 2013 Share Posted January 28, 2013 Hmmmm Stack Water guage and matched semder fitted now tells me I am going to have a cooling issue with the 5.2 Yesterday a "Enthusiastic" drive saw temperature rise to too hot thats with a viscous Fan , proper cowling AND A SPAL 16" going like the clappers low Thermostat to bring te,mps down, and a oil cooler .... I have been thinking of options Water Wetter - have heard reports it makes a difference. and Ali Radiator, And thats me question, who out there has experience of fitting an Ali rad vs a Std rad ?, whiost mine is a large cored special, I belive somewhere in the dark resesses of my warped little mind that a direct "Copy" if Ali would see it around 20-25% increased in effieceny and as a result lower cooling ? Expereince and know please ? I would also prob have the rad made with its own cowling to suit it and prob go with Alisport rather than summit as its both UK and Alisport sqeauls quality and good reputation and I can have it custom made to size Thoughts please ? Nige Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted January 28, 2013 Share Posted January 28, 2013 https://en.wikipedia.org/wiki/List_of_thermal_conductivities Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted January 28, 2013 Author Share Posted January 28, 2013 Kin Hell....Me HFH Not Prof Stephen Hawkins, any chance of it being translated into "Idiot" ......I do "Idiot" well N Quote Link to comment Share on other sites More sharing options...
Dave W Posted January 28, 2013 Share Posted January 28, 2013 I run an aluminium rad on my 5.7, never have a problem with cooling, in fact in cool weather at cruising speed it pretty much sits at the bottom of the thermostat range. The biggest danger, which is probably worth mentioning with your history..., is that the top of the radiator is exposed on a Defender and on an aluminium rad it's at coolant temperature - putting your hand on an 80-90 degree C piece of metal smarts a bit. This is mine... electric fans only, they only get used when at very low speeds/stationary. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted January 28, 2013 Author Share Posted January 28, 2013 Dave Very nice Did you ever run same engine with a normal NON ali rad and can add on the difference as well ? I think this will have to be the route I go somehow N Quote Link to comment Share on other sites More sharing options...
Dave W Posted January 28, 2013 Share Posted January 28, 2013 I did run it with a normal defender TD rad for a short time (a week or so) but only because the Ali rad was delayed so it was only ever a temporary fitment and it was only used for running the engine up in the workshop. It was noticeable though that with the ali rad the time between the fans switching on and then switching off again when idling in the workshop, was a LOT shorter than it was with the traditional rad. I got the rad made up by a local radiator specialist, can't remember the exact prices but it worked out cheaper than the alisport one and included the two fans. It uses a much wider "mesh" than the original rad too and it seems a lot less prone to clogging with mud as a result. One thing I will admit to as it was a bit of an own goal, it's worth checking before spending loads of cash on a new rad... I have had overheating problems when moving at low speed. It only occurs in certain rare circumstances, sustained 10MPH crawling. I'd thought it was the fans as as soon as you get over 30MPH the temperature rapidly drops. The solution was much simpler and cheaper but took a while to figure it out. In short the way we'd plumbed the heater in was actually detrimental to the coolant flow through the radiator, something that was revealed when i got myself an infra red thermometer/laser thingy which showed that the water at the top of the radiator was actually cooler than the water at the bottom. The moral of the story is to check and double check the way you've hooked up the system in a custom install because you can produce some very odd cooling characteristics if you make too many assumptions. In my case it was the assumption that two pipes that went into a manifold were connected internally to the water pump inlet, when it actually turned out that one was connected to the inlet to the water pump but the other was connected to the output of the water pump so connecting the expansion bottle to it was probably not the best idea we've ever had ! Quote Link to comment Share on other sites More sharing options...
Smego Posted January 28, 2013 Share Posted January 28, 2013 My Ali rad is great, doesn't act like a heat sink so the water is cooler faster. Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted January 28, 2013 Share Posted January 28, 2013 Kin Hell....Me HFH Not Prof Stephen Hawkins, any chance of it being translated into "Idiot"......I do "Idiot" well N Bigger numbers mean faster heat transfer. Copper is higher than aluminium - so in theory a copper radiator should perform better. If people are seeing better performance with an ally radiator, then there must be another reason for it - something to do with the construction maybe? Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 28, 2013 Share Posted January 28, 2013 Nige, I had this issue when I stuck the 4.0l in the Rangie, what was your eventual cooling layout of heaters pipes, thermostat housing, thermostat etc? I found with the horrid plastic thermostat arrangement I had issues keeping cold when cruising ~50mph... or using the loud pedal. Swicthe dit all back to '3.9 RRC' spec and sorted. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted January 28, 2013 Share Posted January 28, 2013 My Ali rad is great, doesn't act like a heat sink so the water is cooler faster. Um, surely the entire point of a radiator is to act as a heat sink? There's lots of stuff that affects rad performance - cores & fins-per-inch being two major factors, overall system capacity which helps slow down temperature fluctuations & absorb jumps. I believe Nige is running a very open-cored copper rad at the moment so it will not be as efficient as a more "normal" one, but the flipside is it doesn't clog up with mud and is more robust. There's also the question of the fans, their performance, switching point for the electric one, and what happens when you're chatting along at motorway speed and the fan powers up, is it running faster or slower than the air trying to get through the rad? I would pause & take a look at the whole system before spunking £500 on a custom ali rad. As TRE says, copper is a more efficient conductor of heat than ali. I went with copper for mine as it's also more easily field-repairable and less fragile. Quote Link to comment Share on other sites More sharing options...
Les Brock Posted January 28, 2013 Share Posted January 28, 2013 Would now be a good point to mention the Die-sels run cool anyway Quote Link to comment Share on other sites More sharing options...
reb78 Posted January 28, 2013 Share Posted January 28, 2013 I dont know if my posts here http://forums.lr4x4.com/index.php?showtopic=80260 on the M&D uprated tdi rad are helpfu for this topic? I know my rad was for my tdi - but it was a copper core, deeper with a different fin pattern to the original LR design - but they might be able to fit an uprated core to the wider rads used for the v8s? Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted January 28, 2013 Share Posted January 28, 2013 reb78 - that's pretty much what Nige (and me) are running. This is mine, with a 4.6 behind it it only gets proper hot if you give it serious abuse in low-box. It's quite small too, full-width in a Series but only about 36cm tall from memory. Quote Link to comment Share on other sites More sharing options...
reb78 Posted January 28, 2013 Share Posted January 28, 2013 Ah. Ok - that does look similar with the fins running vertically and containing the rows rather than fins concertinered between the rows. How deep is it? Could you go deeper with different tanks? (i can measure the depth of mine if its any help). Not sure increased depth would have as much effect though as increasing the front surface area? Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted January 28, 2013 Share Posted January 28, 2013 I don't think it's a rad problem at all, I reckon it's the arrangement of the fans or something like that. As I said, well worth doing some science before handing your arm + leg + spare kidney to Alisport for a shiny rad that doesn't solve the problem. Quote Link to comment Share on other sites More sharing options...
Team Idris Posted January 28, 2013 Share Posted January 28, 2013 Copper vs aluminium isn't any real difference on water, as the performance is driven by the air side, via; fin pitch, fin area and profile (plain vs wavy vs serrated vs louvered profile). The metal doesn't screw you untill you start on stainless steel. Steel seems fine (but fairly industrial). My self and Darren fixed guy up with a 100mm pace core He said it nearly needed the choke on tickover But beware of cavitation if you have a free flowing rad with no thermostat and the engine (pump) is running at high speed. It can be an any-V8 problem, not just modded RV8. I can do an open fin ideal for mud-dipping. I sell it for quarry work. But it will need to be deep (100mm) and I can't 100% garantee the perfomance as no one knows the pump pressure-curves for the RV8. And it will be expensive. If messing with the pipe work doesn't fix it, Andy Allisports brain and product is a really good place to start 1 Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted January 28, 2013 Author Share Posted January 28, 2013 OK By all means check the set up and comment if any ideas ? Rad Turbo diesel side tanks with 6 row gillet core (used in JCBs open and tough) Top hose from rad to thermostat Thermostat fitted 78 degree one additional 3x 3mm holes to Sid bleeding and save engine if therm jams Bottom hose from radiator to waterpimp Top of rad has 2 x small Hoses 1 goes into bottom hose the other to the outlet on the front of the inlet manifold Header tank biggish hose to bottom hose and bleed to top of radiator other goes to small pipe on pass side front of inlet Cowling made to be as good fit as possible Viscous fan SPAL 16" on front of rad and oil cooler on other side on front Antifreeze at 38% Ali header tank with std pressure cap Fan controlled by auto switch off bottom of rad via switch set to come on at 88 go off at 79 Vents x4 in sides of wings That's about it comment away !! N Quote Link to comment Share on other sites More sharing options...
Daan Posted January 28, 2013 Share Posted January 28, 2013 I reckon the open cored rad is hurting you. The expensive way is obviously the allisport or similar one. But I would have a look at modern OEM ones, they are aluminium, with the plastic tanks crimped on. They are very effective and lightweight. I bet a large enough one like a 4.6 rangerover will do you. I am sure there are now people shouting that the plastic tanks could split, but pop the bonnet on any recent car, and you will see they are all like that. Also, are you saying that it overheats at decent speed? You should only need fans at stationary or low speed IMO. I have spend quite a bit of time in the past to seal the air path between the grille and the rad, to make sure all the air that goes into the grille also goes through the rad. Polystyreen foam and tankape are your friend. Then you have the problem of air bleeding out again. It may be good to have some bleed holes in the bonnet, but you probs have that already. Daan Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted January 28, 2013 Share Posted January 28, 2013 Viscous fan SPAL 16" Is that a viscous unit and an electric unit? I'd have thought that they'd get in each other's way. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted January 28, 2013 Author Share Posted January 28, 2013 Viscous on inside of rad SPAL on outside Spal knocks 10 degrees off temp when stationary Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted January 28, 2013 Share Posted January 28, 2013 Daan - the open cored rad is undoubtedly less efficient, but Nige has probably ~20% more area than my open-cored rad of similar design and I'm pushing a low-geared 4.6 V8 along. Discussing this with TSD today, I said I reckon it's the fans but not sure why, TSD reckons the Spal is blowing so much through one patch of rad it's pressurising the cowling and "blowing back" through the rest or at the very least stalling the airflow. You may find it would drop if you pull the fuse and let natural airflow do it. You shouldn't need the fan on at speed, and the BHP of your engine is fairly irrelevant as it only ever takes X horsepower to move a 90 along the road at 60mph or whatever regardless of whether it's a 4.5 V8 or a 2.5N/A, it's only hard acceleration or (very illegal) speeds that require more BHP and hence more heat. How hot was it getting? Bear in mind a 78deg stat won't even be fully open till around 84 or more deg (the 88deg one is just fully open at 92deg according to RAVE if memory serves) so until then you're not even hitting full water flow. If only you had some way of posting a data-log sort of picture showing what the engine temps are doing and the driving conditons, eh Nige? Quote Link to comment Share on other sites More sharing options...
jad Posted January 28, 2013 Share Posted January 28, 2013 Is the electric fan blowing the correct way? I knew someone that connected the wires the wrong way and was sucking air out of the engine bay... Jad Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted January 28, 2013 Share Posted January 28, 2013 My bet is that the fans are getting in each others way. 2 x fans does not mean 2 x the flow. Pull off whichever one is easier and see what happens... Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted January 28, 2013 Author Share Posted January 28, 2013 Tried that needs both when slow and hard worked Nige Quote Link to comment Share on other sites More sharing options...
Ash.Witty Posted January 28, 2013 Share Posted January 28, 2013 Do you have a heater? If not and your running a serpentine V8 you need link the bottom hose to a port on the top of the inlet manifold before the thermostat. This allows the coolant to circulate round the engine until it reaches the point of which the thermostat opens then it flows through the radiator. Why have you decided to run a lower temp thermostat As this won't cure overheating as the cooling systems not up to scratch. Whatever you decide don't run an engine without a thermostat as you are asking for premature wear. Quote Link to comment Share on other sites More sharing options...
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