What if your radiator is plugged up? You mentioned you flushed the
system and it needed it - perhaps silt/rust has plugged up the
passages in the radiator. You might take it to a shop and have it
boiled out.
Silly questions, but it pays to cover the bases - is there a cooling
fan, and does it turn? Is there some sort of cowl missing that may
be preventing the fan from drawing air through the radiator? Is the
water pump belt tight? Is the thermostat in the right way around?
What if you run without the thermostat?
Does it still overheat if you put a box fan running full tilt right
in front of the radiator?
Is it possible your valves aren't closing quite all the way? Gummed
up valves or gummed up seats or damaged somehow?
How are you measuring overheating? You mentioned that the manifolds
were red, so that's a pretty good indicator, but ... I chased
'overheating' problems in my Spitfire for two years before
discovering it was the gauge that was faulty, not the cooling system.
Anyone else have any other thoughts?
HTH,
Dan
>I have been going around in circles on this problem and am becoming
>convinced that I am missing something obvious.
>It is with a tractor but I'm going to claim LBC content as it is a Vanguard
>derivative...and the folks on the tractor lists are less scientific than
>you guys...
>1. Needed timing chain. Took great care to line up very faint marks on
>crank and cam gears, ensuring chain was tight on the side that is under
>tension when doing so.
>2. Set valve stem gaps.
>3. Found TDC and installed distributor with rotor pointing at cylinder #1.
>4. After flushing some old gas through, started up and ran well, but
>overheated severely, quickly.
>5. Thoroughly flushed cooling system; it needed it.
>6. Checked thermostat; it's fine.
>7. Started again, still overheats - like in three or four minutes.
>8. Played with ignition timing, retarding and advancing so now I don't know
>where it is. There is no timing mark.
>9. Got to be evening and tried again; noticed exhaust manifold and muffler
>glowing red; shut it off.
>11. Thought it might be an air leak in the intake, so took off manifold,
>looked fairly OK but cleaned mating surfaces thoroughly and replaced gaskets.
>12. Still no luck.
>
>Now, I have always thought too hot would be from timing too far advanced,
>but then I was reading where overheating can be caused by timing too far
>retarded as fuel burns late i.e. in the exhaust manifold. but if I advance
>it to try to fix that, it seems to run far too fast
>
>Any thoughts?
>Confused in Ontario
--
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Dan Buettner - Des Moines, Iowa
1957 TR3 TS15098L 'O', going back together with glacial speed.
Fiberglass is the word of the day.
1977 Spitfire FM64159U 'O', in storage, waiting for its big brother
to free up room in the garage.
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