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Old 02-14-2003, 08:51 PM   #1
tkeduk8r
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Help!!!!!

well lastnight i went to put my rod from the air horn to the fast idle cam back on so my choke will work properly (the tang that locks it on to the fast idle cam is worn, so it slipsout occasionally) and i had a small oil leak in the rear of my valve cover gasket, so I figured as long as i had the garage warm I would fix that too. So in order to put the rod back on the carb the airhorn must be removed so i did that (i removed the carb to do it on the work bench, much easier) and before i placed the valve cover with new gasket on (i had just had the head in for a valve job) I re- tourqued the head bolts, and turned the rocker arm nuts down 1/8 additional turn to snug everything up (I had heard some light ticking with the new lifters i installed). Put everything back together, and ran it and now i have no ticking, but a constant miss, and i cant get any more than 15-16 inches af vacuum, where b4 i had 22-24in. The vac hoses are all new and I even blocked each off to systematically check each vac circuit. My timing is right on fac spec and does NOT jump around, and i have spark to each cylinder. Tonight i pulled the airhorn off again to check the gasket for any cracks or bad spots. replaced it and i still have the missing... Could my adding 1/8 turn to the rocker arms cause that prollem???? Or retourquing the head bolts??? I thought i had adjusted teh rocekr arms correctly b4... Im puzzled out ofmy mind!!!! I fi did something stupid PLEASE tell me!!! by the way its a 250-6 with original Rochester MV carb set up, although i did add an HEI.... thanks agin,
--Mike
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Old 02-14-2003, 08:57 PM   #2
cableguy0
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seems to me like u have one of the valves too tight causing your miss and low vaccum. i would back em all off and readjust with the engine running until they stop ticking and just go another 1/2 turn
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Old 02-14-2003, 09:01 PM   #3
Jackal2k9
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that is strange you should have 1/8 turn left in all of them with ut messing anything up. Might as well readjust them though. if they are hydraulic its easy. pull the covers start it up and with it idling as low as you can get it run each valve out one at a time until it barely begins to tick then go back down 1/4 to 1/2 a turn.
1/4 turn = horsepower tune, 1/2 = torque tune.
then the vavles will be right for sure. To keep oil off of you either use an old set of valve covers and cut/drill the tops out so you can adjust vavles, or find a set off sbc valve adjsuting clips taht fit over the oiling holes in the rockers.

How long has it been driven that way? if they were too tight it could have wore a lobe off(1/8 of a turn wont make a good adjustment too tight)... that will make it idle rough and seem to miss because it continually increases the duration and lowers lift and then at one point the valves ceases to open at all.
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Old 02-14-2003, 09:09 PM   #4
tkeduk8r
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I only drove it about 10 miles round trip to get to work and back, thats it.. i figured a hydraulic lifter would take that minute touch, i know i would never attempt it with a solid lifter, but im definetly second guessing that move right now.... any other ideas??? or is this a pretty open and shut case????
--mike
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63 C20 2WD, 230/SM420/4.11 73K
68 C30 dump truck, 327,SM425,4.56 66K original
68 C10 2WD SWB Stepper, 250/3-tree/3.73 66K.... Wifes
68 Buick Skylark Custom Conv., 350/TH400/2.56 In our family since '79
69 GMC 1500 SWB 2WD, 350/TH350/3.73 posi...
70 K10 SWB 4X4 4-sp,ps, pb, tilt, buckets, console, sliding back window (Need AC parts) WIP
72 Chevy K20 4x4 350/350/205/4.56 donor
72 Vette 350/M21/3.70 posi, triple black and super fast
84 Olds Cutlass Brougham 350/2004r/4.11 was Dad's
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Old 02-14-2003, 09:11 PM   #5
tkeduk8r
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OH!! and ive seen those clips in summit and jegs, but does a regular auto parts house carry that sorta thing (Like National Bushing/Auto Value, Champion, etc.)????
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63 C20 2WD, 230/SM420/4.11 73K
68 C30 dump truck, 327,SM425,4.56 66K original
68 C10 2WD SWB Stepper, 250/3-tree/3.73 66K.... Wifes
68 Buick Skylark Custom Conv., 350/TH400/2.56 In our family since '79
69 GMC 1500 SWB 2WD, 350/TH350/3.73 posi...
70 K10 SWB 4X4 4-sp,ps, pb, tilt, buckets, console, sliding back window (Need AC parts) WIP
72 Chevy K20 4x4 350/350/205/4.56 donor
72 Vette 350/M21/3.70 posi, triple black and super fast
84 Olds Cutlass Brougham 350/2004r/4.11 was Dad's
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Old 02-14-2003, 09:14 PM   #6
Jackal2k9
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i doubt it i have never owned a set, just borrowed until i found a set of rusted out valve covers and drilled them blasted and repainted so i could adjust through the holes in them. The guy i borrow them from has been racing since the 70's his are probably antiques by now
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Old 02-14-2003, 09:19 PM   #7
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o ya make sure your chocke isnt stuck close or anything.... that might do it.... and if it is stuck closed youll have to clean the plugs afterwards too. sometimes you can just take it for a high rpm run to clean them.
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Old 02-14-2003, 09:24 PM   #8
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Valve 2 tight

that is more than likely the culprit.been there done that with the same results as you have.Yes the clips work great but the oil will still pool up and cause a fricking mess.Put the clips on then take a piece of cardboard and put at the bottom of the head(by the exhaust)it will work as a dam and wont splash on the exh. causing smoke,stinky smell. The cardboard from the valve cover gasket set works great
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Old 02-14-2003, 09:27 PM   #9
Jackal2k9
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lol kaycee.... never tried the cardboard.... couldnt find a good sized piece im thinkin about marketing my valve cover with holes in the tops lol i could make plugs for the holes and then it would really be some trick stuff. someone's surely done tht already..... damn
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Old 02-15-2003, 08:28 PM   #10
tkeduk8r
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Thanks guys!!!! well i went out readjusted teh valves today and that was definely the ticket.. runs smooth as glass right now!!!! I was able to find valve clips for the oil spurt holes for 7.95 at auto value for a set of 16 and in conjunction with the cardboard box from the valve cover gasket, no oil burnin... all the trix worked well, so thanks alot again...
--mike
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63 C20 2WD, 230/SM420/4.11 73K
68 C30 dump truck, 327,SM425,4.56 66K original
68 C10 2WD SWB Stepper, 250/3-tree/3.73 66K.... Wifes
68 Buick Skylark Custom Conv., 350/TH400/2.56 In our family since '79
69 GMC 1500 SWB 2WD, 350/TH350/3.73 posi...
70 K10 SWB 4X4 4-sp,ps, pb, tilt, buckets, console, sliding back window (Need AC parts) WIP
72 Chevy K20 4x4 350/350/205/4.56 donor
72 Vette 350/M21/3.70 posi, triple black and super fast
84 Olds Cutlass Brougham 350/2004r/4.11 was Dad's
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