my van is a 92 lite ace on a 5k engine. i already replaced the radiator,thermostat, hoses, water pump,
aux fan, rad caps. there are no signs of leaks and the cylnder head just fine. . Theres no problem when i get stuck in traffic and the temp just holds at 82C. but when i go cruising on the highway, the temp rises and which forces me to stop and top off with water. i'll treat lunch to anybody who solves my problem. thanks
- (#14547) boogie, 13 Dec 04 19:14
Does your van run a Viscous coupling ? If so you will hear the roar of the fan when the motor starts-up and when the motor is hot.If you can't hear the fan the Viscous coupling is u/s.If running an electric fan ,make sure it's running when motor is overheating or hot.Check for air bubbles in the coolent as well,as head gasket may be u/s
- (#14547) paul, 13 Dec 04 19:59
Also, if your vehicle does have the viscous fan, have you done a visual check with the passenger seat up, at speed, with a hot engine? Paul is correct that the fan "roar", caused by the viscous coupling driving the fan instead of allowing slippage, should be able to be heard but, it is not always recognisable, especially in traffic and with wind noise.
- (#14547) John Davis (Leics), 14 Dec 04 02:44
I had similar problem with my spacecruiser. Whenever I tried to check the fault with the engine cover open, it never overheated!! I suspected an air flow problem - air buffeting or something?
I've read similar problems before in Ace Answers, overheating on a run, especially on a hot day. I found that if I slowed down to around 50-55mph the temp would come back down again.....So that's what I used to do! Pity, I never knew this site existed then, till I bought my Townace.
I can also remember someone commenting on the front number plate. The UK positioning is directly in the line of air flow. They had done tests and found that the number plate position did effect the cooling efficiency. Evidently the Japanese put it somewhere else so it wasn't a consideration during manufacture.
Just another thought.....A previous owner hasn't removed the fan cowling, have they? That would effect the air flow.
Stewart
- (#14547) Stewart, 14 Dec 04 16:41
A good indicator that your Viscous coupling is suspect is every time you start the motor,even when cold,you can hear the noise of the fan. The noise will then die-off after about 20 seconds if cold ,or keep on running if motor is hot.Toyota vans seem to have very little natural flow through air to the radiator,so on a hot day,or running at speed, the fan is a must.
- (#14547) paul, 14 Dec 04 17:04
I forgot to say if you can't hear the sound of the fan that the Viscous coupling is likely to be u/s.
- (#14547) paul, 14 Dec 04 17:21
after a lot of research about overheating and having
thoughts about selling my van, i gave it one more chance and replaced the head gasket myself. the old gasket seems fine,no burn marks or whatsoever except that it looks old and original. to make the story short, it was the head gasket after all!!!!! I haven't added a drop of coolant for a month now. Thanks for all
the help. also i get to keep the lunch to myself.haha
- (#14547) boogie, 15 Feb 05 00:38
Boogle
is your 2 wheel drive or 4 x 4
- (#14547) dennis, 17 Feb 05 13:28
If your van was needing to be topped up after its high speed overheat, and there was no visual leak or sign of water from radiator cap, then the head gasket/cracked head is most probable. Overheating without loss of water would indicate possibly radiator or fan etc
- (#14547) Frank, 17 Feb 05 14:39
Us fallas down here speak bad enggrish
- (#14547) Frank, 17 Feb 05 15:03