I just finished doing head gaskets on my 91 Toyota 4Runner. I'm having a problem with it overheating when I put a load on it. Like accelerating up a hill. It also seem to have a little miss to it . I just pulled the timing cover back off and my marks line up. I put new plug wires on. The water pump I replaced about 8 months ago.Any ideas as to why I'm over heating ?
Radiator flow restricted, radiator hoses collapsing under high flow, head warped, head gasket put on wrong, cooling fan pushing instead of pulling air.
I would look at the radiator being plugged, or thermostat hanging up..
I took the thermostat out , 2 weeks ago I was driving it with no heating problems . I triple checked the gaskets before I put them on . It just blew a head gasket , the temp never got to hot to warp anything. I checked them with a straight edge.
I watched the water flow with the cap off , It seemed to move ok . The fan is on correctly.
So you took the thermostat out and the overheat problem went away, that would tell me that you have a faulty thermostat.
No the heating problem did not go away when I removed the thermostat
Then have the radiator flow tested. It may look like it is flowing but when the load comes on it is not.
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