Proper way to adjust vavles

Big-E

Petty Officer 2nd Class
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May 2, 2005
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135
I thought i saw a post on here about how to adj the vavles without running engine and have oil get everywhere but am unable to find it. <br /><br />I got them very close before i even started the motor but it sounds like a couple of them aren't 100%. <br /><br />1988 3.0 L mercruiser 4 cyl (just rebuilt)<br /><br />any help is appreciated as hopefully this saturday "sometime during the day" I will drag her out to the lake and give her a proper break-in. <br /><br />thanks, <br /><br />Big-E
 

Don S

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Re: Proper way to adjust vavles

This is from the Mercruiser service manual for your engine.<br /><br />
Valve%20adjustment%203.0.png
 

Laddies

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Sep 10, 2004
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12,218
Re: Proper way to adjust vavles

With the engine on #1 cyl. TDC adj, 1-I&E, 2I, 3E,4I -turn 1 revolution then do, 2E, 3I, 4E
 

Big-E

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May 2, 2005
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Re: Proper way to adjust vavles

Thank you very much guys, Thats what i was looking for. I really need a FSM. My Clymore manuel says to adj with engine running. <br /><br />thanks again, <br /><br />Big-E
 

Silvertip

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Sep 22, 2003
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Re: Proper way to adjust vavles

The following technique is beneficial for a shop where the procedure is done frequently but for the do it yourselfer it may be a little "over the top" (but equally effective). Buy a valve cover from a junk yard. Drill holes in the top of the cover in-line with each of the rocker pivot nuts. Size the holes just slightly larger than the socket you will be using but such that you can buy plastic hole plugs that fit. Head to the hardware store and buy eight plastic hole plugs. Install seven of them in the holes. Install the cover and fire the engine. Adjust the first lifter by loosening the nut til the lifter rattles. SLOWLY tighten the nut til the lifter just quiets. Then give the nut (SLOWLY) 1 to 1-1/4 turn. Install a plug, remove the next one and repeat for each valve. This process makes sure things are quiet and you don't have a messy engine bay. I also saw a cover that had a slot cut the full length of the cover over the adjusting nuts. A heavy rag laid over the slot would stop any oil that might otherwise get out. You would obviously use a deep socket for the adjustment and preferably weld it to the extension so there is no chance for it to pop off and make additional parts.
 

rodbolt

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Sep 1, 2003
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20,066
Re: Proper way to adjust vavles

follow the service manual procedure. adjust the valves on the engine stand, button it up and run it. no reason to adjust valves on a modern engine while running. just makes a mess and increases the chance of valvetrain damage. when using the #1 cyl TDC method make sure its TDC compression stroke. it will be at TDC twice per cycle but only TDC compression stroke once. compression stoke can be identified by the intake valve is closing, when it closes continue rotating the engine the correct rotation until the TDC marks lines up
 

PeteHarris

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Apr 19, 2004
Messages
47
Re: Proper way to adjust vavles

If you go to an auto parts store you can get little clippy thingies that deflect the spurting oil so you can adjust with the motor running without the mess ... pretty cheap and simple
 

Silvertip

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Re: Proper way to adjust vavles

I've used them and they still make a mess. They've been in a landfill for years.
 

Scaaty

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Re: Proper way to adjust vavles

Adjusting valves on a running motor is a heart surgeons job...the rest see post 1+2
 

Big-E

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May 2, 2005
Messages
135
Re: Proper way to adjust vavles

update : thanks Don S. for posting that tech for me. I adj them today and she ran even better. Just getting things ready for saturday when she will touch water for the 1st time in about 5 years. <br /><br />thanks again, <br /><br />Big-E
 
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