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Is a 270 degree cylinder head normal?

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Brickyard
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Location: North Florida

Is a 270 degree cylinder head normal?

Post by Brickyard » Sun Sep 13, 2015 5:50 pm

Trying to diagnosis a slow return to idle/ not returning to idle problem, I went out and bought a timing and temperature gun. Ensured timing marks at advance (3500 rpm) was within the advance lines. Also verified no air leaks in carbs and that my mixture screws were 1 1/4-1/18 open. Had a fan pointed directly at the engine.

More likely than not the rust particles I saw in the fuel lines were no longer there after fiddling with the timing, so I likely have clogged jets causing my not returning to idle problem, but thats beside the point....

Shot the temperature laser at the cylinder head while it was running, and it read 270 degrees!!! That seems WAY too hot for any engine! Please pitch in

OldScrambler
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Post by OldScrambler » Sun Sep 13, 2015 7:23 pm

Just warming up..................as measured at the exhaust port.

Blocked low-speed jets usually causes the motor to 'die'..........If the slides are closing properly, your fuel-level is too high in the bowls.

Brickyard
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Joined: Tue Mar 26, 2013 6:49 pm
Location: North Florida

Post by Brickyard » Mon Sep 14, 2015 3:59 pm

OldScrambler wrote:Just warming up..................as measured at the exhaust port.

Blocked low-speed jets usually causes the motor to 'die'..........If the slides are closing properly, your fuel-level is too high in the bowls.
OldScrambler, are you saying 270 degrees is normal temperature for a cylinder head? When i checked the exhaust pipes they were much lower, and the block was about the same.

rrietman
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Post by rrietman » Mon Sep 14, 2015 9:42 pm

B; CHT in the 450's are OK for air cooled motors. I have seen 550 on highly stressed VW/Porsche motors. get your head around the air cooled thing.
Randy

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