Valve adjustment question

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CRM

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I've seen two different ways to adjust hydraulic valves like the ones in my 250 I6. One was to set the Harmonic Balancer at TDC and adjust certain valves, then move the HB 180* and adjust the rest. The other way was to mark the HB at six equal positions starting at TDC and adjust each cylinder's valves at it's corresponding position.What are your thoughts on this?
 

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It can get complicated and confusing to do it either of those ways. The two easiest ways are what I call "the messy way" and "the easy way".

The messy way is to pull the valve cover and start the engine. Loosen each rocker until you just start to get a clatter, then slowly tighten until it gets quiet(the point where it gets quiet is zero lash), then go 1/4 turn more. Do this for all valves and you are done.

The easy way is to remove the valve cover and adjust each valve using the EOIC method. Hand turn over the engine and observe the valves. Adjust the exhaust valve when the exhaust is closed and the intake for the same cylinder has started to open. Then rotate more until the intake closes and the exhaust just starts to open, then adjust that intake valve. Then move to the next cylinder and repeat.

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Doing it with the cover off would be my last choice. Oil all over the engine bay is not something I want to deal with. I'll watch the video above and see if I can do it that way. I've got all the nuts loosened up with wiggle in the valves. Hopefully I can get to it tomorrow.
 

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I think I'm going to mark the distributor at every spark plug wire location and adjust both intake and exhaust on the cylinder that the rotor is pointing to.
 

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I did the TDC and move 180 degree method to do the rest. Worked fine on my 350.
Eric
 

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I have an old distributor cap so I thought I'd cut the top of it off, set the engine at top center, and mark each cylinder plug location. I can turn the engine manually until the rotor lines up with each cylinder, verify piston is at it's top position, and then adjust the valves. What do you think?
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Just an update:
I've adjusted the valves according to the service manual, hooked everything back up, and no start. I do have spark but it seems that there's no fuel. I'm considering taking out the new fuel filter and trying it that way. If I were to install an inline filter then it seems like I wouldn't need the filter installed in the carb.
 

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Use a spray can cap or other small container to measure out a few ounces of fuel. Hold the choke open and pour gas directly into the carburetor, and then try again to start it. If it fires (and maybe starts), you have a fuel delivery issue. If it still won’t fire, you need to recheck the distributor and ignition.
 

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I poured a cap full of gas into the carb. Got some large back fires. Removed the filter and hooked up the fuel line. More back fire. Loosened the distributor enough to move and rotated it back and forth, but only back fires. Is it possible that the distributor is in backwards?
 

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That 100% sounds like you have the distributor in 180* off.
 

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I did set the timing at 0* TDC and alined the distributor rotor at spark plug #1 when adjusting the valves. I guess I'll pull the distributor and move it 180*. Can't hurt I guess.
 

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I have an old distributor cap so I thought I'd cut the top of it off, set the engine at top center, and mark each cylinder plug location. I can turn the engine manually until the rotor lines up with each cylinder, verify piston is at it's top position, and then adjust the valves. What do you think?
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So first of all for me when I'm working on a customers car doing a valve adjustment with the engine running is NOT an option due to the mess.

I've long hated adjusting valves. It's not that I can't do it I just find it tedious and boring. TDC the engine, adjust valves, move the crank to next specified position adjust again, and so on. I just find it to be a PIA and time consuming. And if you get anything wrong you get to do it again, what fun. Often I find I'll under tighten valves in an effort not to over tighten them which puts me in there again.

The next valve adjustment I need to do I'm going to try the cap cutting method. If it works out ok and makes it easier on my I'll absolutely cut their existing cap and give them a free new cap and rotor. Maybe it could be a promotion at the shop get a free cap and rotor with every valve adjustment lol.
 

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I did set the timing at 0* TDC and alined the distributor rotor at spark plug #1 when adjusting the valves. I guess I'll pull the distributor and move it 180*. Can't hurt I guess.
Also if you overtightened the valves badly enough that could explain a no start and backfiring. Testing a cylinder or two with a compression gauge could give you an idea if that is what happened. Though personally I think it's unlikely I'm just throwing it out there as an idea.
 

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I've tried two different ways to adjust the valves (the service manual version twice). When I did the first one it wouldn't start and I thought I'd over tightened, so I remove the cover and do it again, but a little looser. No change. According to the service manual both valves on a cylinder are closed when spark takes place, so I don't think the distributor could be backwards 180*. When I used the cut cap I had the spark plugs out and verified the pistons were at the top of their stroke before adjusting the lash. Now I wish I'd have just left them alone and put up with the ticking noise. I'll eventually get it figured out though.
 

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