Hi Dave, I remember you saying 2 years ago at the Classic that despite fitting an aluminium rad it didn't seem to have done much good and you were still running too hot. It is strange that it only happens when stationary though as a decent rad and fan should soon pull down the temperature. As Andy says, I would do all the basic checks first especially as the rad didn't fix the overheating. 1. Does the electric cooling fan still use the standard switch in the cylinder head or was it replaced with a switch that senses from the matrix - either way my handbook says the switch should be set to start the fan at 94*C and cut back out when temp drops to 86*C 2. Does the fan run at full speed, is it single or 2 speed fan? 5. Were your top and bottom hoses replaced and or in good condition and not collapsing at tickover. 6. System may not have been backflushed when radiator was replaced - do you know when it was last backflushed and filled with fresh 50/50 anti freeze - bottle of water wetter doesn't go amiss either (Red Line or Millers) 7. Have you checked the twater hermostat is opening - standard thermostat should be fully open at 88*C - don't just replace it as you need to test to prove this is or isn't the problem 8.Replace radiator cap if it is the original 9. Does the coolant stay up to the mark in the remote header tank - even if it runs hot it should not lose any coolant 10. Of course the water pump itself could be faulty - although they tend to get noisy and or weep a bit first before seizing - worth checking before replacing a pulley though. Don't know what it does to the belt adjustment if you fit a smaller pulley 11.Is aluminium rad a roadgoing version and not a full blown oversized 4.6 racing version as they need speed to generate maximum cooling and may not work so well in traffic as they aren't designed for that. 12. Do you run the engine with oil up to the mark and does the level have an affect on your problem - does dipstick fully push in and is it the correct dip stick length - low oil can make a difference to engine temperature if the level is marginal. Hope you sort it out Richard M800RGN+8
________________________________ From: Andy Garlick <[email protected]> To: mogtalk2 <[email protected]> Sent: Tuesday, 17 July 2012, 21:07 Subject: Re: [mogtalk2] Plus eight water pump. Technical Dave Before going down such a route consider some (debatably) easier options: 1 Is the car chipped? This will richen the mixture slightly and help it run cooler. Is the air filter clean? Are you sure it is allowing the engine to breathe sufficiently? Try a K & N type? Are you sure there are no air leaks allowing the engine to lean off? 2 Is the alloy radiator larger than the original , or the same size? My Mulfab one is deeper by several cms. 3 Are you sure you don't have any air locks in the cooling sytem? 4 Have you changed the expansion tank cap recently, they can age and allow the water to boil at a lower temperature. 5 Have you backflushed the system recently , crud in the bottom of the rad can affect water flows a lot. 6 Is the number plate or anything else impeding the air flow into the radiator core? 7 Are you positive that you don't have any head gasket issues? Regards Andy >________________________________ >From: Dave Ager <[email protected]> >To: mogtalk2 <[email protected]> >Sent: Tuesday, 17 July 2012, 20:43 >Subject: [mogtalk2] Plus eight water pump. Technical >Hi All.My plus eight has the normal problem of getting hot when stationary.I >have opened the rear of the bonnet 40mm and fitted an aluminium rad.Still have >a slight issue.Before fitting an oil cooler a guy at LeMans suggested fitting >a smaller pulley to the water pump to draw more water through the system.With >a standard 97 3.9 hotwire I believe I may have room on the pump to try this, >engine doesn't rev as high as a worked 4.6.However before I start machining a >billet I would like to check the pump characteristics to ensure I don't end up >with cavitation in the pump.Currently toying with a 10-15 % speed increase.Now >the point . Can anyone provide a spec for the water pump, preferably with >characteristic curves.Thanks in advance.Dave97 plus >8-------------------------------------------View posts on The Mail >Archivehttp://www.mail-archive.com/[email protected]/ >[http://www.mail-archive.com/[email protected]/]Modify Your Subscription: https://www.listbox.com/member/?&Powered by Listbox: http://www.listbox.com/ View posts on The Mail Archive http://www.mail-archive.com/[email protected]/ Modify Your Subscription 3. Is fan wired correctly and running the correct way i.e. pulling air through the matrix and not blowing it back as they are designed to work one way only - don't know if its possible for the rotor to be fitted backwards on the shaft either 4.. Do you know your temperature gauge actually displays the correct temperature ------------------------------------------- View posts on The Mail Archive http://www.mail-archive.com/[email protected]/ [http://www.mail-archive.com/[email protected]/] Modify Your Subscription: https://www.listbox.com/member/?member_id=22459785&id_secret=22459785-4a39ddf8 Powered by Listbox: http://www.listbox.com
