In the "Spotted" thread chrisselby suggested that leaving, or somehow holding the engine lid slightly open during a long journey helps the cooling. (Thanks to chrisselby for bringing this up Does anyone have an opinion?
You go to all that trouble to seal your engine bay against the hot air around/under it that it doesn't make sense to leave it open
Keep the lid shut. You'll find stuck in a jam is when your a/c engine is coolest unlike our water-cooled friends. It'll only get too hot if you go too fast for too long.
When stationary hot air and exhaust fumes are sucked into the cab ventilation system as well. The flaps on the Hexs are never airtight when closed One way to overheat the engine and get a stinking headache as well.
Did about 50 miles after leaving open after a short stop and a check. Ooops! Wondered why we were getting some funny looks from folk overtaking.
Really Zed ? You're not jesting ? I thought that a stationary van in traffic would just suck warm air in and a moving van would suck cold air. You are pulling my P****r are you not ?
No, it's only a bit air-cooled. Really it's oil cooled. Hot oil when doing 50, very hot oil when doing 90. Warm oil at tick-over in traffic.
^all of the above. Keep your engine lid firmly shut. I have heard tales from folk who've measured that temps actually go up with the lid ajar. Sitting in traffic, you're probably overcooled, given than you've still got that big fan going round.
The cooling fan runs at the speed of the engine, the faster you go the more the engine is cooled. No need to worry about extra cooling unless your running larger than stock. Remember these 40 year old buses run happily all day long in the clogged sweaty streets of Mexico etc so the uk weather won't cause problems
I have ze oil temp guage and sat at tickover even after a good thrashing it cools down lovely. However if you're running close to the cooling limit it appreciates slowing down by 10mph for half a mile if you know you're going to stop and switch it off. In fact it runs at a steady oil temp until you hit the magic speed that the cooling can't keep up with, then it gets hotter and hotter until you slow down or blow up. That speed depends on the type and state of your engine/carb/tin/thermstat/flaps etc and likely to come down a bit in hot weather compared to winter. IMHO the only way to avoid going over disaster speed is from experience of overdoing it and stopping in a cloud of oil smoke because the thin oil has leaked out onto the heat exchangers (if you're lucky), or having a temp or pressure guage. Up to the point where the oil gets too hot, which is quite sudden, the pressure remains more or less constant. When it crosses the line it suddenly thins and the pressure plummets so either guage will tell you it's too hot. If you want to push it get a pressure guage rather than a temp guage, because the temp guage won't show you the point the oil thins, but by showing you how thick the oil is, the pressure guage will tell you when it's too hot if you see what I mean.
Thanks zed. I was trying to avoid the 'worry' guages and was relying on the light only, as I tend to only drive around 50-55 mph anyhow ! This has been a good lesson for me so thanks bryandsi for starting the thread. Better start looking at guages then ! I guess if I drive fairly sedately at 50-55 (60mph downhill), i can get away with a temp guage and dipstick oil temp sender.
You're not pushing it lofty, you'd know if you were without a guage TBH and if it's all stock and in good order it'll be happy doing what you do. Guages are more use if you have twin carbs, and/or non-stock engine, where you might be a bit into the unknown with the cooling/jetting and can easily go too fast for it's own good. Then again I know someone who's 1600 with slightly rich Dells would cruise at 70 all day long, so there is no definitive max speed to keep under. It also depends on hills, wind direction etc. With my standard 1700 could always smell when I was overdoing it...
Getting a temp guage for a type 4 engine is very difficult for some reason. Unless anyone can advise?
That'd be me But with the Porsche cooling, I'm over cooling at idle, regardless of the outside temp and hot exhaust gasses!!
