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hellride731
06-27-2009, 03:02 AM
My engine is all apart. Is it possible to set the timing a 180 degrees out the wrong way? I mean if I set the valves chain mark zero at 12:00 and the timing mark as Smithers has his in his assembly post. Can it be on the wrong stroke? Always firing at the wrong stroke? Do they fire at the same time or does the timing fire everytime and so that one piston gets the wrong spark at the wrong stroke everyother time? If anything im having a lot of fun with this project

RobG
07-11-2009, 03:10 AM
There is only one points on this engine so both sparks always fire simultaneously. Only one cylinder is firing at a time so basically you are just sparking in the exhaust stroke on one side. Having the timing 180 out will just change which cylinder fires 'first' per rotation cycle. The shop manual (I just packed mine! I am moving) should have a diagram, but I think I am actually running mine 180 off from the pictures on here. I don't remember.

ghoti10
07-23-2009, 06:32 PM
In a related timing question...is it possible to bolt the cam sprocket to the wrong holes? There's supposed to be a difference in the spacing of the 3 bolt holes but I can't see it in my motor. But I can't seem to get the valve clearance right and I'm starting to get suspicious about my rebuilding ability. I haven't made any progress in a couple of months. Thanks for the help.

RobG
07-24-2009, 06:32 AM
I don't believe you can. Two of the holes should be closer to each other than the third hole. At least this is how it was on mine. If you are having valve clearance problems, check the alignment of the two sprockets. You can get 1 tooth off and have the valves just tap the top of the pistons but the engine will still turn over. 1 in the other direction and they mash pretty hard.

If all else fails, send pictures! : )

Smithers
07-24-2009, 03:41 PM
Yeah you can't screw up the install of the cam gears. Just pop off the cam gear cover and check the marks on the crank. It's kinda hard to not get them lined up if you are taking your time. Now my Acura Integra on the other hand was REALLY hit and miss when I put on the timing belt last month. I had to redo it as I was one tooth off on the belt. I know all the tricks and everything - but the marks are just still really hard to get perfect. It was either to the mark on one side... or you put it on the next tooth and the mark would be to the other side! So I had to do it twice which is no fun. But I can do a timing belt on that car in about 25 minutes now! =]

Just be glad you aren't doing the timing on this little pain in the butt... the angle the picture was taken makes the marks look off, but they actually line up really close. Move the belt one tooth and it looks that far off in the other direction.
http://lh4.ggpht.com/_M_ebNyNrvFw/Skjh-WKKOFI/AAAAAAAADXI/oHL7x8cOjYw/IMG_8374.JPG

ghoti10
07-24-2009, 04:26 PM
The photo shows the cam sprocket timing mark on the top. At the same point the "T" on the crank is lined up with the timing mark on the rotor and both pistons are at tdc or very close. I can adjust both intake valves to specs but when I rotate the crank 180 degrees, I cannot adjust the exhaust valves. Ain't this fun? Plus, do I adjust both intake valves then rotate the crank and adjust the exhaust valves? Or do I adjust one intake valve and the exhaust valve on the opposite piston then rotate 180 degrees and do the other intake and opposite exhaust? I'm gonna go take a couple excedrine and go lay down now. Ya'll have a great weekend.

ghoti10
07-25-2009, 07:52 AM
Ok, here,s a couple shots of what I was talking about last night.The first one shows cam sprocket mark on the top while the rotor mark is lined up with the "T". The second shot shows the alignment of the timing sprockets. I used a silver Sharpie to highlight the sprocket marks. Thanks to everyone for their help on this project.

Smithers
07-25-2009, 08:42 AM
I changed the name of the proper thread as it wasn't so easy to see. So here is all the info you need. It's easy! SOrry I didn't point you in the right direction before. I couldn't remember what thread the Honda timing information and pictures were in.

Old Honda timing and cylinder head installation: http://www.fourwheelforum.com/showthread.php?t=108

ghoti10
07-26-2009, 05:39 PM
Ok, I took the cam sprocket off and made sure it was bolted in properly. I made sure the cam sprocket timing mark was at the top of the sprocket and the timing mark on the crankshaft sprocket was at the bottom of that sprocket. In other words the marks are as far away from each other as they can be. That's the way I interpreted the service manual. Now, I set the tappet clearance on, let's say the left intake valve. Do I also set the right exhaust valve at the same time? Then rotate the crank 360 degrees and set the right intake and the left exhaust? Or do I set the tappets all at the same time or do I do both intakes then rotate the crankshaft and do both exhausts? This is my last set of questions on this subject. But you can bet I'll find more subjects. :)

RobG
08-10-2009, 04:35 AM
I just got out my service manual (I found it after doing my rebuild) and I have a picture showing that the official way of setting the timing marks is 'up'. The cam sprocket mark goes toward the top of the head. The crankshaft sprocket mark also goes to the top of the head. The book's wording makes it sound like it is as you said, as far as possible. Though as we have said, 180 out makes little difference. Both sparks fire simultaneously.

That said, the manual doesn't say much about the valve assembly. I will say that rotating the crank 360 won't change anything. When the pistons are at top dead center, you should have 2 valves closed on one piston (the power piston) and an exhaust valve just slightly open on the other. (Yes, even at TDC one valve is slightly open on one side. This is why the valve timing is so damn tricky). If you know which is the power piston, I would adjust both valves on this side simultaneously, then go 180, and do the two on the other. You can check for the power piston by pushing air through the exhaust of both cylinders at 180 or 360 to see which one seeps. That is provided they actually seal : p

ghoti10
08-11-2009, 06:35 PM
Thanks much RobG. My cam sprocket mark is at 12:00 but the crankshaft mark is at 6:00, as far apart as possible. I'll change the position when I get time. I understand that 180 out just changes cylinders firing but something is not quite right with my motor. Kinda like my brain most days. Later and thanks again.

Smithers
08-11-2009, 08:47 PM
It's super easy. Just follow my pictures and you got it made. Mine started on the first kick remember... LOL. seriously though... :)

RobG
08-12-2009, 02:37 AM
Before you search the timing problem too far, it probably isn't the timing. I would guess you have it right. I messed with the timing for 3 weeks only to find out that there was a wire out of place elsewhere and I was missing 1 half of the coil under firing. The timing light made it look like something else. Maybe you can start a thread with the syndromes you have? If the engine cranks and the valves don't tap the cylinder, you probably have the sprockets right.