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  1. #1
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    88 Blackmax v6, cylinder 3 running hot

    There is no bleed line going to cylinder 3, it's a 5 hose bleed system. Cylinder 3 is running up to 20 deg higher than any cylinder on the port bank, and 10 deg higher than cyl 1 and 5 as measured with a ir temp gun. Would the lack of bleed line running to cyl 3 cause it to burn that much hotter, or am I looking at a lean condition that needs to be addressed?


    Thanks!

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    Shouldn’t make any real difference. Are you measuring with a temp gun?


    '95 STV "The Blue Goose"


  3. #3
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    Quote Originally Posted by mach351 View Post
    Shouldn’t make any real difference. Are you measuring with a temp gun?

    That's what i was afraid of. So 5-10 deg hotter would be normal? Yes, measured with a temp gun. I've tried the propane thing looking for a vacuum leak, didn't really tell me much. Have checked the pulse feeds to the fuel pump, and the blocked off oil injection feed (could these cause a vacuum leak?). Have recently chem dipped and rebuilt the carbs, & reset the floats. Haven't checked the plugs yet.

    Carb base gasket?

    Thanks

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    How hot are we talking? Are the thermostats and poppet working properly? Is it a salty motor? Does it run rough like it has a lean condition?


    '95 STV "The Blue Goose"


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  6. #5
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    Quote Originally Posted by mach351 View Post
    How hot are we talking? Are the thermostats and poppet working properly? Is it a salty motor? Does it run rough like it has a lean condition?

    Not overheat hot, at idle c3 141 c4 128 so it's gotten better since I tightened things up. No thermostats at the moment, was overheating with them in. Poppet working. Salty yes. First start after sitting sneezes once and then not again till first start of the day. Not really running rough. Cylinder 3 spark plug was a bit black and sooty, so I'm starting to think the other cylinders are running rich? Haven't read them yet.

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    if its over heating' with stats ya got something wrong goin' on in it somewhere.............. ya haven't said actual temps?.. alarm?
    Last edited by tlwjkw; 08-02-2021 at 01:20 AM.

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