Cam timing questions. Is the Honda Manual Correct?

[misterguitar]

Ok so I have the engine out. I replaced the timing belt night before and today went through all the valve adjustments and shims. In doing this I removed all the cams. Not a big deal right? Well I started putting it all back together per the service manual. When I went to do the left side, wham ran into problems! The manual says to line up t1 and the line son the right side and punch marks on the left side will all line up. Now it took me 30 minutes to realize the "punch marks' they referred to were little dots and not the actual lines. So I got the intake cam on no problemo. Can;t put the exhaust on in this position becasue the front lobes are down and pushing on the buckets. Am I doing something wrong or is this manual wrong?

 

[dwalby]

Its been a long time since I've pulled the cams, and I recall there being punch dots, but the Honda manual doesn't provide info on how the punch dots should align.

edit: found this with a web search:

Yes, the Honda manual is incorrect. Set the crank pulley at T1 with both camshaft pulley marks lining up. At this point you can install the right hand side camshafts all as per the manuals instructions. The manual is correct up to this point. Now turn the crank pulley clockwise until the T4 mark lines up and install the left hand side cams. Make sure the cam lobes for no 2 cylinder are facing each other and the lobes for no 4 cylinder are facing away from each other. The two dots on the cam gears will align up with the cylinder head surface. Cylinder identification as seen from sitting on the bike. Right hand side front is no 1, Right rear is no 3. Left front is no 2 and guess which one is no 4? Hopethis helps

and another reference about the manual being wrong suggests that the two dots should face inwards, which wasn't specifically mentioned by the first quote.

 

[John OoSTerhuis]

Good catch, Doug! I was studying my manual and couldn’t figure out what was wrong to start with, much less how to respond/help. I’ll save your quote and paste a copy in the manual. Where’d you find it?

Edit (28Sep’19): the web clip is wrong, the Honda Service Manual instructions as written are not in error. The punch marks (“dots”) are not used during the reinstall of left side camshafts with the crank at T4. The dots are only noted when the crank is at T1 (#1 @ TDC)! Follow the Honda Service Manual carefully and use the camshaft Index Lines as instructed.

Good luck, miSTerguitar

John

 

[misterguitar]

Thanks! Gonna try this at home tonight! I was going crazy trying to figure this out. I did it by the manual but slowly turning the engine over afterwards I would hit resistance. Next time I'm using a marker to make SURE everything goes back! I repairs stereos as a hobby too and there are entire books worth of information about stereo makers errors in service manuals! I shoudl realize mtorcycle FSM's are no different lol.

 

[dwalby]

John, these are the two references in my first post, I found them with a web search:

SOLVED: The timing marks in the honda manual didn't work. - Fixya

The timing marks in the honda manual didn't work. I need the timing marks for a 1995 honda ST1100 - Honda 1995 ST 1100 Pan European question

www.fixya.com

https://www.tapatalk.com/groups/ukpanclan/error-in-st1100-manuals-t1167.html (specifically post #4)

When I removed my own cams for valve adjustment I vaguely remember there being alignment marks, but did it so infrequently over the years I don't recall the specifics. I must have either not looked at the Honda manual because it was so obvious doing them one at a time, or I noticed the discrepancy and ignored the manual because it didn't make sense and quickly forgot.

I also seem to recall that somewhere there is a compilation of Honda manual typos/errors. If you know where that is then adding these links would help.

 

[John OoSTerhuis]

Thanks, Doug. When I have pulled my cams I marked all the meshing teeth and did one bank at a time. Nothing wrong with the lobes touching the buckets as you tighten down the cam holders as long as the marks are correct.

I don’t know of an errors list. The erroneous moly grease icon instead of paste icon on the rear wheel schematic that has led to a lot of consternation over the years comes to mind. Also the lube for the left front caliper bracket needle bearing. I don’t recommend the manual’s instruction to turn the crank backwards to move the tensioner pulley during a belt R&R! Just use your hand instead of risking the belt jumping teeth on the drive pulley. BTDT

Better get back on topic.

John

 

[John OoSTerhuis]

Hmmm... rereading the two references, John Hudson’s valve clearance worksheet, and my annotated, well-marked-up Honda Manual, I’m wondering about the contention that the left cam index lines should be facing in.

When I replaced the cams after changing shims I followed the manual, and as I said matched up the splines markings; however, I made a note in my manual at the end of Left Cylinder Head procedure (p.8-7): “left cams index lines should face out.”

So.. I’m wondering if they shouldn’t face out if the crank is still at T4 after 1 1/4 turns CW from T1 after finishing the right side. Where are they after turning to T1 after doing the left side? Where are they at T1 on a correctly set up and running ST?

I’m not going to remove Front Covers right now to find out. Anyone else....?

John

 

[dwalby]

Hmmm... rereading the two references, John Hudson’s valve clearance worksheet, and my annotated, well-marked-up Honda Manual, I’m wondering about the contention that the left cam index lines should be facing in.

When I replaced the cams after changing shims I followed the manual, and as I said matched up the splines markings; however, I made a note in my manual at the end of Left Cylinder Head procedure (p.8-7): “left cams index lines should face out.”

So.. I’m wondering if they shouldn’t face out if the crank is still at T4 after 1 1/4 turns CW from T1 after finishing the right side. Where are they after turning to T1 after doing the right side/on a correctly set up and running ST?

I’m not going to remove Front Covers right now to find out. Anyone else....?

John

The source of this confusion lies in how you arrive at the T4 alignment mark.

Starting from the T1 mark when at TDC #1, rotate 90 degrees to reach the T4 alignment mark, at TDC #4, and the cam markings should face inward.

Another option is to rotate the crank 450 degrees instead of 90, you reach the same T4 alignment mark, but you're at TDC #2, and the cam markings should face outward.

Both methods are mentioned I believe in the Honda manual in various places, but I don't have it in front of me now to confirm. Since the two methods differ by 360 degrees of crank rotation, and the cam orientations differ by 180 degrees it all makes sense.

Also, in the quote I provided in post #2 he mentions the cam lobes for #4 cylinder should be pointing away from each other after rotating 90 degrees from T1 to T4, as I recall that lobe orientation is consistent with TDC #4.

 

[Jim Van]

I'm a little disappointed since every time ( three times, so far ) I have checked my valve clearances they all have been dead-nuts right in the center of the spec. Sounds like I've been missing out on some fun.

In a situation like this, I would say some common sense over-rules the tech manual.

 

[dwalby]

I'm a little disappointed since every time ( three times, so far ) I have checked my valve clearances they all have been dead-nuts right in the center of the spec. Sounds like I've been missing out on some fun.

In a situation like this, I would say some common sense over-rules the tech manual.

I'm disappointed in you Jim, I would have bet money that you change out the cams for PM every other year.

 

[John OoSTerhuis]

The Honda manual camshaft installation procedure:

NOTE
If the right camshaft has been removed, install it first, then turn the crankshaft clockwise 1-1/4 turns (450 degrees) and align the T4 Mark with Index Mark.

Edit: During a simple valve clearance check, you rotate the crank to TDC of cylinder #1 (T1 mark, RHS camshafts’ index lines face out) and measure its clearances. The sequence then is to rotate the crank only 1/4 turn further to the T4 mark and measure the #4 cylinder’s clearances. At that time the LHS cams’ index lines should face in. Then 3/4 turn to T1, #3 clearances, RHS cams’ index lines in. Finally a further 1/4 turn to T4, #2 clearances, LHS cams’ index lines out.

 

[Jim Van]

I must admit, I have been bummed-out every time I have checked the valve clearances and found them to be dead-nuts in the center of the range.

In fact after I did the check, I measured my feeler gauges with a micrometer to make sure they were correct , then I measured them again with my neighbors micrometer to be absolutely certain. But no joy , the feeler gauges were dead-nuts on too !!

BTW, the extra timing belt guide plate that I installed a few years ago hasn't chewed-up my new timing belt either, and my rebuilt water pump seems to be working just fine.

 

[dwalby]

I must admit, I have been bummed-out every time I have checked the valve clearances and found them to be dead-nuts in the center of the range.

In fact after I did the check, I measured my feeler gauges with a micrometer to make sure they were correct , then I measured them again with my neighbors micrometer to be absolutely certain. But no joy , the feeler gauges were dead-nuts on too !!

Jim, to help improve your mood, next time pull the cams and replace some of the shims with the incorrect size. Then check all the clearances and re-adjust them correctly. And buy a 2nd micrometer, no sense bothering the neighbor again, you can never have too many measuring tools.

 

[misterguitar]

ok I may have just realized my error. when the manual says right cams does it mean right side from the drivers seated perspective or right side from facing the front of the engine? (they never say in the manual which is which!) Becasue int he manual for the cam installation the picture they give when they say do the left cams is a picture of the cam on the right side from facing front. I'm starting to think I have the cams on the wrong sides! OK yep after walking down the cams on the right side from the front of the engine are stamped R. Guessing those should be stmaped L?

 

[dwalby]

ok I may have just realized my error. when the manual says right cams does it mean right side from the drivers seated perspective or right side from facing the front of the engine? (they never say in the manual which is which!) Becasue int he manual for the cam installation the picture they give when they say do the left cams is a picture of the cam on the right side from facing front. I'm starting to think I have the cams on the wrong sides! OK yep after walking down the cams on the right side from the front of the engine are stamped R. Guessing those should be stmaped L?

all left/right references are sitting on the bike facing forward.

 

[misterguitar]

crap. I know what the problemo is! But after I got home I did finaly realize there wer every tiny round PUNCH marks on the timing gears and now knwo the difference between index and punch marks and now I know the orientation of right and left! Off to fix my mistake!

 

[Jim Van]

Jim, to help improve your mood, next time pull the cams and replace some of the shims with the incorrect size. Then check all the clearances and re-adjust them correctly. And buy a 2nd micrometer, no sense bothering the neighbor again, you can never have too many measuring tools.

Doug : I seriously doubt the clearances will ever be anything except dead-nuts in the center of the allowable range. They haven't changed in 50K miles.

But I bet when I do the first valve clearance check next year on my '08 Concours C-14 I will have to pull the cams and change some shims. Can't wait for that !! I had to get the Concours because I ran out of stuff to do on the ST1100. Kinda sad, isn't it ? BTW, doing a throttle body balance on the Concours is an absolute PITA compared to a carb balance on the ST1100.

 

[John OoSTerhuis]

in the manual for the cam installation the picture they give when they say do the left cams is a picture of the cam on the right side from facing front.

Careful reading shows that the line drawing of the right side head illustrates the Right cylinder head section of the instructions. If it helps, draw a straight horizontal line across that page in the manual just below that illustration. Then you’ll note the next section which is titled: Left cylinder head and the illustrations to the right of that section’s text refer to it.

I have to admit that in all my years this is a firST. No harm done though, thankfully.

John

 

[John OoSTerhuis]

When you start over, be sure the #1 cylinder (right front from the view sitting on the ST looking forward) is at TDC. Left front is #2, right rear is #3, and left rear is #4.
As long as the cams are out, pull each bucket and record the three digit number marked on each shim. Then when you do a valve clearance check in the future you’ll know what’s in there and if necessary what size replacement to get.

John

 

[dwalby]

OK, here's 3 different pages from the Honda manual, all talking about cam installation. In one of the pages it does mention the punch marks on the left cams, on the other two it does not. Use info at your own risk.