Topic: Guys, Im Sorry...cam/crank/valve lash adj. kickin my ass AGAIN!

[timdhawk]

Trust me, I know!! I'm sorry fellas. I cant explain why i'm so dense on this topic. I've reviewed my other post on this very subject as well as many other "cam 180* out" posts and I seem to be more confused now than before.

My crank is at TDC on the 1.4 T mark. With my cam notch on the end oriented at 12:00, my #1 lobes are in the overlap ("V") position and the #4 base is pointer up...all per the manual! The manual says I should be able to set intake lash on #'s 1 and 3 but #3 is under tension and I cant adj it. I have stared at this for over an hour and I just cant see what im doing wrong... again!!!
My cam is a mild street grind one from web.

PLEASE be patient and understanding. I know this should be basic common sense, Ive done it 2-3 times in the past... but this is kicking my ass and I don't know what the hell am I doing wrong?

[tlbranth]

Well since nobody's answering......Mine's a '70 and here's how it goes: With timing mark on 1-4 T, right side of camshaft should be positioned with index line parallel to top surface of camshaft holder with key groove up. So # 1 has both cams sticking up and #4 has both cams pointing down.
From here, I adjust as follows: turn engine until a valve is fully open (rocker on top of cam) and adjust its opposite e.g. #1 exhaust fully open, adjust #4 exhaust, #3 intake fully open, adjust #2 intake. If you do it this way you don't have to remember any rules or tables. So #1 is opposite to #4 and #2 is opposite to #3.
Good luck.

[DH]

Well since nobody's answering......Mine's a '70 and here's how it goes: With timing mark on 1-4 T, right side of camshaft should be positioned with index line parallel to top surface of camshaft holder with key groove up. So # 1 has both cams sticking up and #4 has both cams pointing down.
From here, I adjust as follows: turn engine until a valve is fully open (rocker on top of cam) and adjust its opposite e.g. #1 exhaust fully open, adjust #4 exhaust, #3 intake fully open, adjust #2 intake. If you do it this way you don't have to remember any rules or tables. So #1 is opposite to #4 and #2 is opposite to #3.
Good luck.

Yep, I've even gone as far as picking a cam lobe, rotating engine till rocker arm of chosen lobe was on base of lobe (lowest point) and adjusted to spec, not worrying about any special sequence. It takes longer, but the result is the same.This was of course, when the valve cover was off and I could see the entire valvetrain. What matters most is that before any valve clearance adjustment is made for any valve, the corresponding rocker arm must be on the BASE of the corresponding lobe.
At least, I've never seen different.

[goldarrow]

In the honda shop manual, page 42, #3a down at the bottom of the page, it says "while slowly rotating the crankshaft..." Did you follow that?  When you install the camshaft, yes the notch is at 12 o'clock position, Ignition mark at 1-4 T.  Once that done and you're ready to adjust the valves, then turn the crank again,  as the manual stated to 1-4 T mark.  Then adjust the O.  Then one more revolution, then adjust the X

[iron_worker]

Here's my procedure:

1) Remove fuel tank, all the valve inspection covers, and points cover plate.
2) Rotate the crank (CW ... always CW) until the 1-4 T marks like up at the points.
3) Check the rockers on the #1 cylinders and #4 cylinders. One of which will be at the top of the compression stroke (and the other the top of the exhaust stroke). The one that is on the compression stroke will have both valves fully closed (IE should have valve lash). Wiggle the rockers to find which cylinder has both rockers loose. If you can see in you can also look to see which cylinder has both rockers running on the base circle of the cam.
4) Adjust the intake and exhaust lash of the cylinder you determined to be on the compression stroke in the previous step (rockers loose).
5) Rote the crank 360 degrees CW until the 1-4 T marks line up again. If you adjusted #1 in step 4 then adjust both intake and exhaust on cylinder #4 now (or vice versa).
6) Rotate the crank until the 2-3 T marks line up. As in step 3, check between cylinders #2 and #3 to determine which is on the compression stroke.
7) Adjust the intake and exhaust lash on the cylinder that you determined to be at the top of the compression stroke (rockers loose/on base circle of cam) in step 6.
8 ) Rotate the crank 360 degrees CW until the 2-3 T marks line up again.
9) Adjust the lash of the  intake and exhaust of the #3 cylinder if you previously adjusted cylinder #2 in step 7 (or vice versa).

It seems long now that I write it out but it's all about just making sure each cylinder is on the compression stroke and then you can adjust the intake and exhaust lash of that cylinder. It's a methodical way that helps me not to screw up or miss any valves.

IW

[Vinhead1957]

+ 1 on iron_worker. You can do it with just 2 turns of the crank but it is an acceptable way also

[timdhawk]

I swear to God I have taken this phuking head apart 25 times and still seem to get it wrong.

lets try this: lets do this from the standpoint of a fresh rebuild (which technically im doing) i.e. no tappets installed yet just the cam in place and all valves closed - no ability to find a compression stroke. With crank at the "T" of 1,4 and the cam installed correctly (theoretically) the base circles of #4 should be skyward and the lobes of #1 should make a "V" facing skyward as well - correct so far?

[goldarrow]

Yes, now install your rockers

[timdhawk]

ok, now ive installed rockers and nothing else... crank on "T" 1,4 and cam notch at 12:00 with #4 base up and #1 lobes at 45* pointing up.
according to manual I should now be able to set clearance on #1 I and E, #2 E, and #3 I.
Here's why I'm getting so frustrated - #1 I & E rockers are loose, but #2 E and #3 I are not!!!

[Nic]

Whenever I do tappets I simply turn the engine over so the tappet I want to do goes down then comes up, roll the engine a bit further and just set that one. Do the same for the rest of em. If your cam timing is right what's the problem, I think you're over thinking it really.

[tlbranth]

To borrow from your spelling book, phuck the manual. Better you UNDERSTAND what you're doing. 1&4 pistons move together. 2&3 pistons move together. It's a 4 stroke per cycle engine so 1&4 are 2 strokes apart, 2&3 are 2 strokes apart. When #1 exhaust is all the way open (look through the hole 'til it is, #4 exhaust is all the way closed - adjust it. Do the same for the rest. On a piece of paper, draw a bird's-eye view of the engine with a circle for each valve. Slowly turn the crank and eyeball all the rockers until one is all the way (close is good enough) on top of a lobe (just watch its movement). When that happens, adjust its opposite (e.g. #2 intake on top of lobe, adjust #3 intake). Then on your piece of paper, check off the valve you just adjusted. If you go slow you can adjust all of them with 2 turns of the crank.
Chuck the manual and take time to understand what's going on.

[goldarrow]

Now that your rockers are installed, and your camshaft V still on 1, turn the engine 360 and set the O if you're looking at the manual

[timdhawk]

goldarrow - ok, I did that. #1 base circles are up (more or less) and #4 lobes are now in the overlap (45* V)... but I cant set the light circle O's cause they're under tension.  Im beginning to think Web cams put my notch 180* off (although I recognize its more likely an issue with me).

When I spin the cam so the notch is pointing down THEN I can adjust the valves per the book:
1 I&E, 2E, 3I (dark circles)

tlbranth - I am trying very hard to understand this (conceptually I do get it) but I think im getting to the point where I cant see the forest for the trees for some reason.

[goldarrow]

The notch on the shaft is there so you can set the sprocket and shaft correctly.  When you set the valves, don't worry about the notch, just be sure the ignition plate is where it's suppose to be at T

[DH]

Whenever I do tappets I simply turn the engine over so the tappet I want to do goes down then comes up, roll the engine a bit further and just set that one. Do the same for the rest of em. If your cam timing is right what's the problem, I think you're over thinking it really.

+1....forget the sequence, just turn the engine till one rocker is on base circle of cam lobe (no matter which one) and adjust to spec. Repeat till you've done all 8 valves.

[timdhawk]

so if #1 compression is happening when the notch on my cam is down, even though the manual says it should be up; it doesn't matter in relation to overall timing? Here's a short video as an example...

[tlbranth]

Offhand it looks like you're correct, that the compression on #4 is with the notch up.

[DH]

My Clymer manual says to line up the t1-4 mark, ( that will bring BOTH cylinders 1 AND 4 to tdc,) and install the cam with the notch pointed at 12:00. It DOES NOT specify which cylinder is on its compression stroke with the cam is installed in that position. It is up to you to determine which is at compression and which is on exhaust. The cylinder at compression will have its cam lobes high point pointing away from the rockers.

[DH]

so if #1 compression is happening when the notch on my cam is down, even though the manual says it should be up; it doesn't matter in relation to overall timing? Here's a short video as an example...

correct, except about the manual being wrong, you may have mis read?

[timdhawk]

both service manuals (not Clymers or Haynes) say notch up... that's why I'm so thrown. the last web cam I had in (same grind) had the notch up...

[goldarrow]

The notch on the shaft is there so you can set the sprocket and shaft correctly.  When you set the valves, don't worry about the notch, just be sure the ignition plate is where it's suppose to be at T

[timdhawk]

Thanks goldarrow.
And all others to...I'll let ya know how it turns out.

[Davidov]

Well since nobody's answering......Mine's a '70 and here's how it goes: With timing mark on 1-4 T, right side of camshaft should be positioned with index line parallel to top surface of camshaft holder with key groove up. So # 1 has both cams sticking up and #4 has both cams pointing down.
From here, I adjust as follows: turn engine until a valve is fully open (rocker on top of cam) and adjust its opposite e.g. #1 exhaust fully open, adjust #4 exhaust, #3 intake fully open, adjust #2 intake. If you do it this way you don't have to remember any rules or tables. So #1 is opposite to #4 and #2 is opposite to #3.
Good luck.

Yep, I've even gone as far as picking a cam lobe, rotating engine till rocker arm of chosen lobe was on base of lobe (lowest point) and adjusted to spec, not worrying about any special sequence. It takes longer, but the result is the same.This was of course, when the valve cover was off and I could see the entire valvetrain. What matters most is that before any valve clearance adjustment is made for any valve, the corresponding rocker arm must be on the BASE of the corresponding lobe.
At least, I've never seen different.

This was also my suggestion so you can learn without trying to adjust multiple cylinders.

Turn the crank until one cylinder (start with #1) is on the lowest part of the cam lobe.
If you can wiggle the rocker, the cam isn't applying pressure yet.
Adjust to spec.
Move to next cylinder.

Like the other dudes said, it's slower but you'll understand what is being achieved.

[Nuffsa Fugginnuff]

Everyday a schoolday. Once again I find myself on the 'fat' side of the learning curve. I too am looking at putting a 'milf' cam, so, all the above is grist for the mill.

[iron_worker]

Tell us more about this "milf" cam...   

Agree with others. Forget about the notch. The notch is only for timing the cam to the crank. You don't need it for adjusting lash. If you were setting valve lash on a 750 with the engine in the bike (most likely maintenance scenario) you can't see the notch. With it at TDC 1-4 you've got a 50:50 shot of finding which of the #1 and #4 are are at TDC. It's not rocket surgery or even brain science. lol

IW