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Thread: Holly Help. Re-jet Again Or Power Valve

  1. #1
    Senior Member
    Join Date
    Dec 2009
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    648
    When Would You Re Power Valve? Still Showing Lean And Ive' Re-jeted Richer At Leats 5 #'s.? BOTH PRIMARYS AND SECONDARYS.

  2. #2
    DUCKY
    All the power valve does is supply additional fuel to the main circuit. That fuel is still metered by the main jets. The number on a power valve refers to when it opens and has nothing to do with being rich or lean. There are several conditions that can fake you into believing your motor is lean. What are your determining factors? Do you have any pics of the plugs? What is your combo?

  3. #3
    Senior Member
    Join Date
    Dec 2009
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    648
    Hi Ducky. Two Saterdays Ago While On The Lake After About 30 Minutes I Melted Both Rubber Exaust Hoses And My Motor Never Got Over 140*.
    My 1st Chance To Look At Things Was Yesterday. Upon Pulling Off My Bassets I Noticed A Couple Of Tubes Were White Inside(by The Way The Rubber Was Fine On The Headers Not Melted, Looks Like Exaust Gas Temp Did All The Work) Exaust Valves Were Brown In The Center(tword Stems) And Then Turned White As They Went To The Edge. When I Drained My Bowls To Rejet Again ,fuel Looked Like Mostly Gas And Not Much 110.(it's My Spair Tank Left From Last Year) You Probably Remember I'm The Guy With No Timing Marks) I Did Back Off On My Timing A Little. Could E Mail Pics Of Plugs,cant Seem To Post ? By The Way Turning The Dist Clockwise Is Backing Off Adv. Right?

  4. #4
    fc-pilot
    An over rich condition can cause high exhaust temps due to the extra fuel still burning in the headers. Also late timing can do the same thing because the air and fuel are still burning while the exhaust is being released. I would try to make sure your balancer timing marks are right to begin with.
    Paul

  5. #5
    Senior Member
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    Dec 2009
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    Timing Wise, If You Were Lean, That Would Be Too Much Advance Right? I'LL KNOW WHERE I'M AT THURSDAY I'VE AN APPT. WITH MY MACHINIST TO GIVE ME AN ACCURATE TIMING MARK.

  6. #6
    DUCKY
    Sorry I didn't check back. I am really pleased to hear that you are going to get a good timing mark
    Anyways, I have trouble believing that your exhaust hoses would melt from a tuning only problem but I guess on the extreme ends it is possible. I don't know what your plumbing looks like but I can tell you from experience that those headers are a pain in the azz, especially on a v-drive with a magna-flow or similar water pump.
    Anyways, Paul is right. Excessively late timing could cause a seriously high EGT, as could an excessive over-rich condition but either way performance would be so bad that I think you would catch it beforehand. A blown out power valve will pour fuel directly into the engine through the valves' vacuum port, but the motor wouldn't idle or respond worth a damn and would be chugging black smoke. Please don't take this the wrong way, but I think that after you get your timing marks verified, you should have someone take a good look at your combination and get you to a baseline before you start damaging parts.
    BTW, yes. Turning the dist clockwise does retard the timing.
    You can post pics on the ***boat image center by going here...
    http://www.***boat.com/image_center/index.php
    after uploading your photo(s), right click on it and select properties. Highlight and copy the "location" line. Then when you make a post in the forums, click the little button that looks like a postcard with mountains and paste the location of you picture into the pop up. Have fun!!!

  7. #7
    steelcomp
    I've seen glowing headers, and guys thinking they were running lean, so they added fule. Big mistake! Both guys are corect, above, although I'd be more wary of the retarded timing than a too-rich condition. Retarded timing can burn ex valves in a hurry. A combination of both is asking for trouble, and since you've admitted playing with both the timing and jetting, my guess is that's what's going on here.

  8. #8
    steelcomp
    Timing Wise, If You Were Lean, That Would Be Too Much Advance Right? I'LL KNOW WHERE I'M AT THURSDAY I'VE AN APPT. WITH MY MACHINIST TO GIVE ME AN ACCURATE TIMING MARK.Timing is timing, and mixture is mixture. Too much lead (advance) will not automatically cause a lean condition, just as retarding the timing will not cure a lean condition.

  9. #9
    Senior Member
    Join Date
    Dec 2009
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    648
    I Got A Good 1 For Ya. My Machinist Determined Both Timing Marks Were Ok, But When We Set It At 37* Total , At Initial I'm Past Zero Like 7*after Tdc.
    Nice Eh. 40* Plus In Dist Mechanical Only(no Vac Adv At All) Going To Take To A Dist Specalist In The Morning To Have Him Dial 20-25*. I Was Running Over 60* Total. My Machinist Thought My Jetting Looked Ok? Said Exaust Tubes Were Supposed To Be White. As Far As The Rubber Exaust Tubes Nuking. I've Recently Installed A Thermostat Kit And I Had No Gate Valve On The Bypass Line To Adjust More Water To The Bassett's I PUT ONE ON YESTERDAY.
    I Guess Thats Ok? ANYONE KNOW HOW TO TEST THAT BASSETT VALVE?(10 MIN B-4 IT WENT UP IN SMOKE I SUCKED A BUNCH OF SEAWEED LOOKIN CRAP INTO MY INTAKE GRATE(JET BOAT) AFTER 5 MIN TRYING TO BLOW IT OUT BY PUTTING INTO REV. I GAVE UP AND GASSED IT AND SUCKED IT IN AND SPIT IT OUT. MABEY I PLUGGED SOMETHING.

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