Adjusting valves question please help!

Trying to get this mf 30 industrial rebuilt and back and running. Got everything back together, but it's time to adjust valves. And I need help!

We tried to go by book, however We don't really understand. We found the tdc 1 mark on fly wheel lined it up with dot and tried to adjust the gap to the .012 that's specified for both the valves on cylinder one. Then we turned the crank half turn the book calls for and adjusted cyl. 3. Then turned it another half turn (we were back to the tdc 1 mark) and adjusted both valves on cyl 4. Did it one more half turn and did cyl 2. Now what I don't understand is 1. We had to adjust them a long ways from where they were and we haven't moved them from where they were since taking them off the engine prior to rebuild.
2. When we went back around to check them after adjusting they weren't always in the same place.
3. Why can't you adjust both cyl 1 and 4 at the same time because once you make a full revolution (two half turns) and are back at tdc 1 you adjust cyl 4.

Any ideas?
How critical is this? I've heard of people adjusting them by the sound of the motor.

Thanks!
 
There are 2 TDC's, 1 for cylinder 1 and one for cylinder 4, the same goes for 2 and 3.

I it important to have it EXACTLY at these positions so the valves are closed.
 
Both Valves will be closed on that cylinder when it is NOT TDC, same goes when it is @ 180 degrees.

Set the valves on the cylinder with the valves closed.
 
David G is right. Best way I set valves on four and six cylinder engines is this, on a four for example pistons 1 & 4 are at TDC the same time, the CAM determines which one is ready to fire. I watch the exhaust rocker on #4, when it's about closed and the intake rocker starts to open you can set both rockers on # one. When they are on the overlap period on one set four. Same with two and three. It may help to also right down the firing order1,3,4,2, and place the 4 and 2 directly under the 1 and 3. That's how I learned years ago. If the rockers are on overlap on 2, then set three, overlap on 3, set 2.
 
I guess what I'm not understanding is how to tell. Are you watching the rocker arms as you turn the crank with a ratchet?
If i have adjusted them wrong will I still be able to tell what to do? I think maybe what I did was set the tdc 1 mark based on the mark on fly wheel and adjusted cyl. 1. I think possibly when I adjusted cyl one it WAS at tdc but it WAS not on compression stroke and rather cyl 4 was... How can I check this?

Thanks!
 
An important thing to remember is the cam rotates at 1/2 the speed of the crankshaft, so there is really 720 degrees in a full cycle.
 
(quoted from post at 20:39:11 03/27/16) An important thing to remember is the cam rotates at 1/2 the speed of the crankshaft, so there is really 720 degrees in a full cycle.
So, when the mark in fly wheel (tdc 1) lines up with dot. That means cyl 1 is at tdc compression stroke? Is this definitely the compression stroke for cyl 1?

Or is this mark the exhaust stroke every two rotations it comes around And the mark could be tdc 1 exhaust stroke?

I'm sorry I'm not getting this. I just can't wrap my little pea brain around how to determine when to adjust each valve because once I find tdc 1 and adjust cyl 1 and I turn crank exactly 720 degrees and adjust cyl 4 the mark on fly wheel is at tdc 1 again....

Sorry for confusion!
 

Correction::****

When I turn crank 360 degrees exactly I am back on the tdc 1 mark on fly wheel and adjusting cyl 4
 
(quoted from post at 20:39:11 03/27/16) An important thing to remember is the cam rotates at 1/2 the speed of the crankshaft, so there is really 720 degrees in a full cycle.

Ok. So after doing some research. I think I have a better understanding of how it works. My question now is: If I did adjust them to the .012 on their exhaust stroke:
How would I know? I'm thinking when I used the feeler guage I would have noticed if the rocker arms were one up and one down, but im not sure.

Also, I'm not sure that I got each cylinder at tdc because I was just turning the crank the "approximate half turn" with a ratchet. Is this close enough?

Ps

It did crank after I adjusted them. So, wouldn't that mean I couldn't have adjusted them backwards??

Thanks!
 
You can rock it back and forth a little on the 180 from TDC to see that both are closed on 2 and 3.

I have no clue what you mean by you set the valves on the exhaust stroke.
 
(quoted from post at 06:45:23 03/28/16) You can rock it back and forth a little on the 180 from TDC to see that both are closed on 2 and 3.

I have no clue what you mean by you set the valves on the exhaust stroke.

Ok. And 1 and 4 should be at tdc when mark on flywheel lines up with dot? One is on compression stroke and other is on exhaust.
And next time the line comes around it would be the opposite? Is this correct?
Thanks!
 
Watch your intake rocker on #1 as you turn the motor with the ratchet(making sure you are rotating the correct direction also). After it has opened continue turning until the tdc mark comes up again. When it lines up it is on compression and can be adjusted. After adjusting both valves turn it 180 degrees and adjust #3 the same. Then turn another 180 and adjust #4( should be tdc again only with #4 at compression). Turn another 180 adjust #2 and done. Whatever cylinder you are on both of the valves will be closed. If not on compression stroke one or the other valve may be slightly off of the seat. Another way to tell is bring it up on tdc and pull the distributor cap and look at where the rotor is pointing. It should be either 1 or 4 and which ever one it is pointed to is at compression stroke.

Steven
 
The easiest way for me is to adjust the valves according to the firing order. Set number one when it's on TDC compression. You then (On a 4 cylinder) rotate the crankshaft from 12-6 with a ratchet off the front of the engine. That gives you the second cylinder in the firing order to set since it's on TDC compression. Repeat. An 8 cylinder is 90 degrees or 12-3 on the crank. A 6 cylinder engine is 120 degrees. Four stroke cycle engines must fire all cylinders in a 720 degree cycle. Hope this helps.
 
(quoted from post at 03:39:20 03/30/16) The easiest way for me is to adjust the valves according to the firing order. Set number one when it's on TDC compression. You then (On a 4 cylinder) rotate the crankshaft from 12-6 with a ratchet off the front of the engine. That gives you the second cylinder in the firing order to set since it's on TDC compression. Repeat. An 8 cylinder is 90 degrees or 12-3 on the crank. A 6 cylinder engine is 120 degrees. Four stroke cycle engines must fire all cylinders in a 720 degree cycle. Hope this helps.

I'm pretty sure I have it adjusted right. Thanks!
 

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