Adjusting Rockers 4.3

jdtower23

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Trying to get the rockers adjusted on my '88 4.3 OMC....most of them threaded down close to where they were before(have a pic) but one rocker on the #5 cylinder won't thread down as far as the others.....it seems snug also...I've double checked it and it seems to be in the lifter.....that pushrod is up so I guess that valve is supposed to be open.....it's a TDC #1....

Is this normal? will I be able to adjust it better by turning the motor to a different spot?

Thanks
 

Coors

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Re: Adjusting Rockers 4.3

Run a die down all the way on the rocker stud, then retry it
 

Don S

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Re: Adjusting Rockers 4.3

What method are you using for valve adjustment?
 

jdtower23

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Re: Adjusting Rockers 4.3

Adjusting them at #1 and #6 at TDC...what my manual says....I got the cylinders adjusted with #1 at TDC......now I tried turning the motor over by wrench one revolution....it turned ok little by little then stopped! Didn't get it all the way around....probably 50% to 75% of a revolution

I did have a couple of rockers too loose so the valves probably didnt open....

What can i do?
 

jdtower23

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Re: Adjusting Rockers 4.3

Anyone have an idea? I'm really worried what's causing this...please help
 

Don S

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Re: Adjusting Rockers 4.3

My guess, you were on #6 when you thought you were on #1.
Have you ever worked on an engine before owning this boat??????
 

jdtower23

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Re: Adjusting Rockers 4.3

You mean initially? Honestly, i've never done anything like this....I've worked on cars, but only simple bolt-on stuff.....

Don't know if this tells you anything but it appeared before I moved it that both valves on #1 were closed and the #3 piston's exhaust valve was open.....when i turned the motor a little #3 exhaust was suddenly a lot looser and #5 intake

Thanks
 

Coors

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Re: Adjusting Rockers 4.3

And ,as usual, I won't say anything about a factory manual...
 

jdtower23

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Re: Adjusting Rockers 4.3

I know, stupid.....well worth the $105 now.....

Anyone know what's stopping the motor? I won't be able to sleep tonight until i figure this out....
 

Coors

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Re: Adjusting Rockers 4.3

Wrong, is one turn on yours.
Put on #1 , use finger to feel the pressure, get the balancer to read 0
Exhaust @ 1,5.6
Intake @1,2,3
then turn balancer to;one revolution, to 0 again (this is # 6)
exhaust 2,3.4
intake 4,5,6
 

WAVENBYE2

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Re: Adjusting Rockers 4.3

Maybe this will help.
 

Attachments

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  • rocker arm2.jpg
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jdtower23

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Re: Adjusting Rockers 4.3

Coors,

What I don't get is when I initially set it to what I thought was TDC #1....I really wasn't sure....but I pulled the cap and it was pointing to the #1 locations....I moved the motor slightly while apart.....but put it right back.....

Can I turn the motor backwards like this?

Thanks a lot
 

Don S

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Re: Adjusting Rockers 4.3

Anyone know what's stopping the motor? I won't be able to sleep tonight until i figure this out....

Yea, I know what's stopping the engine from turning. The pistons are hitting the valves.

To strart with, back off all the rocker arm nuts till they are flush with the stud.
I don't even know if you if the valves will move at this point. But, after you do this, see if the engine will turn by hand without hitting something.
 

Coors

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Re: Adjusting Rockers 4.3

Hope you didn't try to start it, if not you are cool.
 

jdtower23

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Re: Adjusting Rockers 4.3

Coors,

Didn't even hook up the battery.....but I tried what Don said.....motor turned back a little....still wouldn't go forward and now it won't do a damn thing! I am so pissed at myself for this....is there anything else i can do other than taking it apart again?

Thanks for your advice
 

Coors

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Re: Adjusting Rockers 4.3

Coors,

Didn't even hook up the battery.....but I tried what Don said.....motor turned back a little....still wouldn't go forward and now it won't do a damn thing! I am so pissed at myself for this....is there anything else i can do other than taking it apart again?

Thanks for your advice

Motor turned back
How?You do have the plugs out?
 

Don S

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Re: Adjusting Rockers 4.3

Did you get ALL the valves backed off?
 

jdtower23

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Re: Adjusting Rockers 4.3

Yes, all the nuts are flush with the top of the stud....
 
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