 Brain check - valve adjustment |
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| ThePaintedMan |
 Jun 4 2013, 05:18 PM
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#1
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Advanced Member  Group: Members Posts: 3,886 Joined: 6-September 11 From: St. Petersburg, FL Member No.: 13,527 Region Association: South East States 
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Okay, so I just need a logic/brain check here. I've been doing valve adjustments the Cap'ns way since I got the car, but Rich suggested I try a go/no go method to see if I can figure out what is causing my backfiring problem.
Basically, I need to get one valve open as far as possible, making sure that the OPPOSITE valve is as closed as possible. In this case, #1 exhaust and # 3 exhaust. So if I'm looking at #1 exhaust and it is open (the rocker has play in it) then the #3 exhaust should be closed solid, correct? Rich, sorry to post this for all to see, I'm just looking for an answer quickly so I can get this buttoned back up before it's dark. Thanks for your help! |
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| TheCabinetmaker |
Jun 4 2013, 05:44 PM
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#2
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
No. If the rocker has play, it's closed. When the rocker moves toward the center of the engine, it's opening.
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| ThePaintedMan |
Jun 4 2013, 06:50 PM
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#3
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Advanced Member Group: Members Posts: 3,886 Joined: 6-September 11 From: St. Petersburg, FL Member No.: 13,527 Region Association: South East States
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QUOTE(The Cabinetmaker @ Jun 4 2013, 07:44 PM)  No. If the rocker has play, it's closed. When the rocker moves toward the center of the engine, it's opening. Shoot, I said that wrong. Yes, when the rocker is fully compressed and isn't moving back up in either direction the engine is turned, the valve is fully open. What is interesting, and as it appeared to me, is that when I was at TDC for the cylinder (#1 in this case), the opposite cylinder's valve did NOT appear to be fully open. Ie, if I kept turning the engine, there appeared to be more inward movement of the rocker, as if it was not at the peak point of the lobe. I don't understand how this is possible, and it's probable that I was just "seeing things" but it's what I think is happening. |
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| TheCabinetmaker |
Jun 4 2013, 06:58 PM
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#4
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
You need to take a good look at a cam.
#1 intake being fully open does not mean the opposing valve is fully closed. The lobes are not opposite of each other. |
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| ThePaintedMan |
Jun 4 2013, 07:40 PM
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#5
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Advanced Member Group: Members Posts: 3,886 Joined: 6-September 11 From: St. Petersburg, FL Member No.: 13,527 Region Association: South East States
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(IMG:style_emoticons/default/agree.gif) and if I had the ability to attempt a teardown and rebuild, I would. But looking at a picture of a cam, it only has one lobe per cylinder.
http://www.socalautoparts.com/images/product/ENG_6210.jpg In my head, it is as follows: An intake valve on the #1 cylinder is fully closed at TDC, then the intake valve on #3 should be fully open, at the peak of the lobe, no? |
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| Dave_Darling |
Jun 4 2013, 08:53 PM
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#6
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914 Idiot Group: Members Posts: 14,982 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California
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There are four lobes on the camshaft. The forward pair of cylinders share two cam lobes (one intake, one exhaust) and the rear pair share the other pair of cam lobes. Intake and exhaust are offset from each other, but the intake lobes of the front cylinders are guaranteed to be 180 degrees apart from each other.
--DD |
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| TheCabinetmaker |
Jun 4 2013, 08:59 PM
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#7
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
This thread is full of brain farts. I just reread my post. I am full of it. Not sure what I was thinking. If one is fully closed, the opposite is fully open.
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| messix |
Jun 4 2013, 09:05 PM
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#8
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AKA "CLUTCH KILLER"! Group: Members Posts: 6,995 Joined: 14-April 05 From: between shit kickers and pinky lifters/ puget sound wa.north of Seattle south of Canada Member No.: 3,931 Region Association: Pacific Northwest |
time to buy a Camry..... (IMG:style_emoticons/default/slap.gif) (IMG:style_emoticons/default/happy11.gif)
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