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Thread ID: 123616	2012-03-07 04:26:00	Mitsi L300 van.	tut (12033)	PC World Chat

Post ID	Timestamp	Content	User
1263513	2012-03-07 04:26:00	My very old L300 is having water problem and I a wondering about the radiator cap. Cant find what pressure it is supposed to be and it is also has .9 on it. I am more used to PSI. What does the.9 equate to? I recently blew a radiator hose and checking now I see that the overflow when heating is not going into the header tank or sucking back when cooling. No visible leaks. Thanks if anyone can help here.	tut (12033)
1263514	2012-03-07 04:28:00	0.9 Bar, about 13 or 14 psi.	R2x1 (4628)
1263515	2012-03-07 05:09:00	0.9 Bar, about 13 or 14 psi. Thanks, I thought it might be bar. 13-14psi seems about standard but I will see if I can find what the van needs. I suspect it might be too high a pressure.	tut (12033)
1263516	2012-03-07 05:25:00	Sounds more like the cap (or something else) is leaking. Only takes a very tiny leak to put the kibosh on the self-replenishing feature.	R2x1 (4628)
1263517	2012-03-07 06:15:00	13 PSI would be the usual cap pressure for a Mitsubishi L300 (1980's-90's). Petrol eng? Antifreeze added? Check bypass pipe for pinholes, check for splits in plastic tanks (if fitted) in radiator (also tubes in core), possible leak in heater core?; a pressure tester is the best tool for this (your local garage may/should do this for free, especially if they get to fix it :)), also check for emulsified oil/water deposits in the rocker cover/oil filler cap (indicates coolant loss into the oil (blown head gasket/cracked head, corroded head/block (through lack of antifreeze)). en.wikipedia.org	feersumendjinn (64)
1263518	2012-03-07 06:28:00	The cap is a recovery cap which means it seals in 2 places on the top of the cap and in the neck. When the water cools down it reduces in volume causing a vacuum which will then suck the water from the overflow or recovery tank o the radiator. When engine heats the water expands and blows back into recovery tank. A faulty cap not sealing the neck or a blocked hose from the tank to the radiator will stop the water flowing back and forth. A cracked head or blown head gasket will pressurize the radiator and blow the water back and sometimes overflow the recovery tank. Can check for that scenario by watching for bubbles in the radiator or getting the water sniffed for hydrocarbons. The cap has absolutely no effect on what temperature your engine reaches it only raises the boiling point. Anti freeze actually raises the temperature of the coolant, it may stop rust, icing and raise the boiling point a little but being denser than water the additive increases temperature. On my plane engine I used to run 100% glycol in the winter and 50 50 in Summer to try and get more control on the temperature. Feer correct get a garage to blow up the radiator and look for leaks, get an infra red temp sensor reading on the top of the radiator and a hydrocarbon sniff	prefect (6291)
1263519	2012-03-07 20:53:00	As noted above a pressure check should reveal. Not sure if a semi closed/sticking thermostat would cause your issues as well. Once drove a delica van (similar or same engine as L300), that was getting slightly low in water, but no obvious leaks. Until a long hard 150 km drive, then parked for a rest, then water instantly leaked heavily from the water pump. The giveaway beforehand was a "fish" type smell from the passenger side, which was the coolant slowly leaking I think, but evaporated during short distant driving.	kahawai chaser (3545)
1263520	2012-03-08 09:28:00	As noted above a pressure check should reveal. Not sure if a semi closed/sticking thermostat would cause your issues as well. Just had the same sounding problem in our son's Mazda Capella and it was the thermostat stuck shut. Replacement cured all ills. Your mileage may vary. The main clue was one side of the radiator system was hotter than the other, and the system was losing water fast but there were no visible leaks at all. Cheers Billy 8-{)	Billy T (70)
1263521	2012-03-12 15:34:00	Thanks for all the sugestions which I have worked through except for the pressure test which would have probably been the important one. (Our local garage burnt down so no access to a pressure tester) What I cant understand is how the cap works. I can understand that as the water heats and pressure builds up then excess water would lift the cap seal and allow the water into the overflow tank. I cant see any way the cap would allow water to be sucked back into the radiator. Does it have a one way type valve in the cap gaskets? prefect, what sort of plane do you have and what engine (Rotax?)	tut (12033)
1263522	2012-03-12 18:16:00	Thanks for all the sugestions which I have worked through except for the pressure test which would have probably been the important one. (Our local garage burnt down so no access to a pressure tester) What I cant understand is how the cap works. I can understand that as the water heats and pressure builds up then excess water would lift the cap seal and allow the water into the overflow tank. I cant see any way the cap would allow water to be sucked back into the radiator. Does it have a one way type valve in the cap gaskets? prefect, what sort of plane do you have and what engine (Rotax?) The vacuum from the cooling and shrinking volume of water lifts the valve off the seat. Yes a 582 on a B22	prefect (6291)
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