Author | Topic |
Location: toowoomba qld
Registered: May 2003
|
overheating cressida
|
Thu, 22 May 2003 12:34
|
|
can anyone help me. i have a mx73 with a 5me that overheats. never around town only on trips, but only on the way back. toowoomba to gold coast {200k} temp stays normal, 5 hours later on the way back around 100 to 150k temp goes off the gauge within 200 meters. i have replaced water pump,thermostat,radiator, hoses and cylinder head. mechanic, radiator shops and toyota have no answer. any ideas or should i cut my losses and sell it.
|
|
|
Location: Brisbane
Registered: May 2002
|
Re: overheating cressida
|
Thu, 22 May 2003 12:58
|
|
Dodgy gauge/temp sensor is a possibility... are there any signs that it's overheating apart from the reading on the gauge?
|
|
|
Location: toowoomba qld
Registered: May 2003
|
Re: overheating cressida
|
Thu, 22 May 2003 13:26
|
|
it is boiling it head off. once it has cooled down it only takes a litre to top off the radiator. there are no coolant leaks. i check the radiator daily and it only is down about an eggcup full. header tank is ok. the head was replaced as the old one corroded out at number 6 cylinder. it is driving me mad.
|
|
|
Location: Sydney
Registered: July 2002
|
Re: overheating cressida
|
Thu, 22 May 2003 15:39
|
|
What radiator fluid are you using? Toyota long life?
Also is the radiator cap holding the pressure? Pressurised water has a higher boiling temp than normal.
Is there enough oil/oil pressure? If there is an oil problem it could also cause the engine to get hot.
|
|
|
Location: toowoomba qld
Registered: May 2003
|
Re: overheating cressida
|
Thu, 22 May 2003 23:43
|
|
coolant not toyota but good quality although getting diluted from topping up with water after it boils. radiator cap has been replaced and is ok. engine oil level and pressure ok. auto trans oil level correct and no shift problems or slippage. the engine is not under load when it overheats ,last time coasting along at 80kph on a slight downhill section of the highway. it is getting dangerous to drive because i am always looking at the temp gauge.
|
|
|
Location: Perth
Registered: May 2003
|
Re: overheating cressida
|
Fri, 23 May 2003 00:52
|
|
i had a simlar problem in my corona - ur radiator will be blocked - mine was 60percent blocked bring it to a r afiator place they flush it out it will be as good as new - it costs like $80 max.
|
|
|
Location: bris
Registered: February 2003
|
Re: overheating cressida
|
Fri, 23 May 2003 03:37
|
|
coronamark2 wrote on Fri, 23 May 2003 10:52 | i had a simlar problem in my corona - ur radiator will be blocked - mine was 60percent blocked bring it to a r afiator place they flush it out it will be as good as new - it costs like $80 max.
|
i was gonna say - have you cheacked your radiator lately?
|
|
|
Location: Brisbane
Registered: May 2002
|
Re: overheating cressida
|
Fri, 23 May 2003 03:51
|
|
See the top post; he says he's replaced the radiator.
|
|
|
I supported Toymods
Location: Epping, Sydney
Registered: May 2002
|
Re: overheating cressida
|
Fri, 23 May 2003 04:42
|
|
simple solution... pull everything out and insert a 1j!
in all seriousness tho, I'd be tempted to either do an engine conversion, or buy another car (an mx73/83 if you're attached to them)
|
|
|
I supported Toymods
Location: I renounced punctuation
Registered: May 2002
|
Re: overheating cressida
|
Fri, 23 May 2003 04:58
|
|
Despite you having had the head checked, I'd be suspicious of the head gasket. Simple enough to have a coolant CO2 test done at a radiator place.
|
|
|
Location: Darwin
Registered: April 2003
|
Re: overheating cressida
|
Fri, 23 May 2003 05:30
|
|
Norbie wrote on Fri, 23 May 2003 13:51 | See the top post; he says he's replaced the radiator.
|
Was it with a brand new radiator though?
|
|
|
Location: Brisbane
Registered: May 2002
|
Re: overheating cressida
|
Fri, 23 May 2003 06:56
|
|
Yeah I remember getting mine "Rod cleaned" and had the same overheating problem 6 months later!
(I don't think I'd ever get a radiator cleaned again, might as well just get a new core the first time, save the hassles)
Also check to see if there is much crap in the AC condenser, mine was filled with lots of tiny bugs and rocks that I picked out with wooden tooth picks (took a while I might add!) which wouldn't help cooling.
Cheers
Wilbo
|
|
|
Location: toowoomba qld
Registered: May 2003
|
Re: overheating cressida
|
Fri, 23 May 2003 11:49
|
|
thanks for the suggestions. radiator is clean, ac condenser clean, new head and gasket, coolant tested. had this same problem before head replaced. when old head corroded out i thought i had found the cause of the overheating, no such luck. this an ex brisbane car and i am starting to think it doesn't like toowoomba, as it never overheats going away only going back. sorry for the weird but this car is really getting to me.
|
|
|
Toymods Board Member
Location: Sydney
Registered: September 2002
|
Re: overheating cressida
|
Sun, 25 May 2003 22:12
|
|
What about the clutch fan? Maybe it;s not enganging... When it overheat is the fan pulling plenty of air through.. Or is it just free spinning.. I had a similar problem on the Mark 2..
|
|
|
Location: Brisbane
Registered: May 2002
|
Re: overheating cressida
|
Mon, 26 May 2003 00:00
|
|
Yeah I remember checking the clutch fan as well, at high speeds my theory was that the fan might be creating like a "wall" for the air hitting it, increasing pressure being the radiator stopping a fair bit of air flow?
Anyway I ripped the fan off and took it to Toyota and bought the special "Viscous Silicon Clutch" fluid ($12?) or something and one of the guys out the back even put it in.
After that you could "feel" the fan switch on and off when driving through medium traffic.
Cheers
Wilbo
|
|
|
Location: toowoomba qld
Registered: May 2003
|
Re: overheating cressida
|
Mon, 26 May 2003 11:54
|
|
thanks guys, the silicone clutch seems ok but it won't hurt to get it refilled. i will take it for a run on the weekend and let you know the results. if it overheats again i guess it's trade in time.
|
|
|
Location: Brisbane
Registered: February 2003
|
Re: overheating cressida (sorry - v.long)
|
Mon, 26 May 2003 14:57
|
|
before you dump the motor, why not try a few more checks (sorry if you've already done them)?
- are all the plugs burning the same (maybe one of more pots is running lean - could be dodgy injector or ignition) (is motor running ok before boil-off?)
- any oil in the water? or when it boils over - any sticky/smelly foamy shit? (head gasket?)
- any water in oil (off-white gack on underside of oil filler cap, or on dipstick (head gasket)
- maybe thermostat is starting to fail (might be suddenly closing after being heated up for a few hours)
- have you tried it without any thermostat (not advisable for long term) - or with a thermostat with a few extra [small] bypass holes drilled in it (longer to heat up but safer if spring/wax-pellet fails)
- clutch in fan centre buggered (is constantly slipping and when heated too much slips even more) - tho've you've already addressed this - i thought they were sealed units?
- fan belt? is not too loose?
- at high or low revs? maybe a combination of fan belt, fan, radiator & corroded vanes in water pump - not enough cooling capacity after everything is at highway temps - and when coasting at low revs.
- is fuel lines getting too hot (heat soak from something) or fuel pressure regulator failing from heat? so engine runs lean?
- is fuel tank near to empty when overheating? so returned fuel heats it up, or is sucking air (either making engine run lean)
- maybe overflow tank is letting air return instead of water only - so when radiator sucks in enough air, pressure in cooling system drops and water suddenly boils? this would only happen after cooling system has pushed out a fair amount of water (e.g. a long drive)
- leak in piping feeding heater?
- was radiator reverse flushed? a few overheats/boil-overs will refill the radiator with rust/particulates/crap from the engine block? Plus regular occurences will remove oxide coating from iron block leading to greater production of oxide material (e.g. the more boil offs, the more corrosion, the more crap released into water)
- after a boil-off event, you should dump the coolant as it will have picked up excessive amounts of rust/particulates - retaining that liquid will further add to any radiator blockages. Coolant also not perform at well (lower ethyl glycol %)
- if you refilled from tank/bore water or toowoomba tap water, it may have too much crap that's reacted with the coolant or alloy bits.
- clean motor down with soapy degreaser and H/P water (to remove any rust stains) then stop and look for leaks as soon as temp starts to rise (e.g. don't wait for steam)
just city driving is losing small amount of water - then point finger at recovery system. Proper recovery system should keep radiator at 100% full at all times.
sudden rise in temp probably rules out electrical (ign or efi) or fuel. I would concentrate on plumbing... or maybe it's just some Toowoomba curse... the place really does suck (having been a poverty-stricken student there).
thechuckster.
|
|
|
Location: Montrose, VIC
Registered: May 2002
|
Re: overheating cressida
|
Tue, 27 May 2003 00:01
|
|
Mate of mine with a Landcruiser recently had a similiar problem - he'd gone to Toyota and bought a new rad when he replaced the engine, hoses, thermostat, etc. - thought he'd go over the thing before he went on a long holiday. After that, it seemed to always be cooking. Eventually he pulled that radiator out again, got it opened up, turned out it was seriously blocked, even though it was 'new'.
|
|
|
Location: toowoomba qld
Registered: May 2003
|
Re: overheating cressida
|
Sun, 01 June 2003 13:09
|
|
thanks for all the help guys, but i give up. drove from toowoomba to brisbane saturday, highway speed and peak hour crawl, no problem. traveled brisbane from southside to northern outskirts from 9am to 3-30 checking caryards for possible replacement, temp never went above mid-range allday. almost back to toowoomba and temp went off the scale while running at 60kph. let the damn thing cool down for 20 minutes and continued home with the temp gauge never going above mid-range. checked the header tank and radiator this morning , no loss of coolant. the cressida goes this week, it's being traded.
|
|
|