how can u tell if TDC is on the intake or exhaust side?
06-09-2005, 04:03 AM
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how can u tell if TDC is on the intake or exhaust stroke?
my orginal question was way too confusing. here's my revised question.
because honda motors are 4 stroke engines instead of 2 stroke, even if number 1 piston is on the tdc, the head could be on the exhaust stroke or the intake stroke. i just wanted to know how u can tell. as far as replacing timing belts, ive done quite a few for my friends and my customers. i also built my motor myself (see signature). but thanks for all ur inputs. and sorry for the confusion again.
Modified by 98B00STED at 1:04 AM 6/10/2005
because honda motors are 4 stroke engines instead of 2 stroke, even if number 1 piston is on the tdc, the head could be on the exhaust stroke or the intake stroke. i just wanted to know how u can tell. as far as replacing timing belts, ive done quite a few for my friends and my customers. i also built my motor myself (see signature). but thanks for all ur inputs. and sorry for the confusion again.
Modified by 98B00STED at 1:04 AM 6/10/2005
06-09-2005, 05:16 AM
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Re: how can u tell if TDC is on the intake or exhaust side? (98B00STED)
you confused me.......
before you removed the timing belt you set it to TDC?? This would be both of the cam gear arrows pointing up. If the arrows where pointing anoy toher direction then no you would not be at TDC.
before you removed the timing belt you set it to TDC?? This would be both of the cam gear arrows pointing up. If the arrows where pointing anoy toher direction then no you would not be at TDC.
06-09-2005, 05:21 AM
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Re: how can u tell if TDC is on the intake or exhaust side? (98B00STED)
TDC is TDC, nothing to do with intake or exhaust sides as such. It's either right or its not.
Line up the marks on the crank pulley, then see if the cams are lined up, if not turn the crank 360 and they should be right...providing you haven't broken your belt that is of course, and it's still on there.
If you're not sure how to do a t-belt, get a professional to do it; bent valves=lotsa cash
Line up the marks on the crank pulley, then see if the cams are lined up, if not turn the crank 360 and they should be right...providing you haven't broken your belt that is of course, and it's still on there.
If you're not sure how to do a t-belt, get a professional to do it; bent valves=lotsa cash
06-09-2005, 07:29 AM
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^^^ Hes dead on
Hopefully that will explain a little more
Position the crankshaft and the camshaft pulleys as shown before installing the timing belt.
Set the crankshaft so that the No. 1 piston is at TDC. Align the groove on the teeth side of the timing belt drive pulley to the V pointer on the oil pump.
Align the TDC marks on intake and exhaust pulleys. NOTE: To set the camshafts at TDC position for No. 1 piston, align the holes in the camshafts with the holes in No. 1 camshaft holders and insert 5.0 mm pin punches in the holes
Modified by 97tegGS at 8:42 AM 6/9/2005
Hopefully that will explain a little more
Position the crankshaft and the camshaft pulleys as shown before installing the timing belt.
Set the crankshaft so that the No. 1 piston is at TDC. Align the groove on the teeth side of the timing belt drive pulley to the V pointer on the oil pump.
Align the TDC marks on intake and exhaust pulleys. NOTE: To set the camshafts at TDC position for No. 1 piston, align the holes in the camshafts with the holes in No. 1 camshaft holders and insert 5.0 mm pin punches in the holes
Modified by 97tegGS at 8:42 AM 6/9/2005
06-09-2005, 08:55 AM
#5
Re: (97tegGS)
^^printed for future use^^
The pin punches. Can they be used to hold everything while trying to remove or tighten the crank pulley bolt?? Or are they just to be used to hold the cams in place while removing and installing the belt.
The pin punches. Can they be used to hold everything while trying to remove or tighten the crank pulley bolt?? Or are they just to be used to hold the cams in place while removing and installing the belt.
06-09-2005, 04:03 PM
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Re: how can u tell if TDC is on the intake or exhaust side? (98B00STED)
maybe my question was too confusing. it confused me a little when i re-read it. because honda motors are 4 stroke engines instead of 2 stroke, even if number 1 piston is on the tdc, the head could be on the exhaust stroke or the intake stroke. i just wanted to know how u can tell. as far as replacing timing belts, ive done quite a few for my friends and my customers. i also built my motor myself (see signature). but thanks for all ur inputs. and sorry for the confusion again.
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06-09-2005, 04:16 PM
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Re: how can u tell if TDC is on the intake or exhaust side? (98B00STED)
Scenerio:
1) Car comes in a with broken timing belt, engine only needs a new timing belt.
2) Rotate intake cam so arrow is up.
3) Rotote exhuast cam so arrow is up.
4) Rotate crank so arrow is aligned with notch on oil pump.
5) Everything is aligned and at TDC
6) Install the belt.
1) Car comes in a with broken timing belt, engine only needs a new timing belt.
2) Rotate intake cam so arrow is up.
3) Rotote exhuast cam so arrow is up.
4) Rotate crank so arrow is aligned with notch on oil pump.
5) Everything is aligned and at TDC
6) Install the belt.
06-09-2005, 04:42 PM
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Re: how can u tell if TDC is on the intake or exhaust side? (98B00STED)
okay, here you go: take out the spark plug of the piston you want at TDC. then put in a compression test hose. crank the engine like a tenth of a second at a time, and when you hear the pfffft of air rushing out of it, and see the hose jump a little, the cylinder is at or near TDC of the compression stroke.
06-09-2005, 05:16 PM
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Pay no attention to all these work-around methods 
Look at the cam lobes and the valves of the #1 piston. At the top of the exhaust stroke, all 4 valves will be open, or partially open (valve overlap). The cam lobes on both intake and exhaust will be pointing downward and towards each other.
At the top of the compression stroke, all valves will be closed, and the cam lobes will be pointing upwards and away from each other.
Now, if you have the engine now and it has no timing belt, then just set the crank so that #1 is at the top and the mark on the lower sprocket lines up with the oil pump. The cam shafts are what's important. Make sure the lobes on the #1 piston are oriented as I described for TDC. Of course the cam gears can only go on one way, and have the UP arrow, so it shouldn't be too hard.
Look at the cam lobes and the valves of the #1 piston. At the top of the exhaust stroke, all 4 valves will be open, or partially open (valve overlap). The cam lobes on both intake and exhaust will be pointing downward and towards each other.
At the top of the compression stroke, all valves will be closed, and the cam lobes will be pointing upwards and away from each other.
Now, if you have the engine now and it has no timing belt, then just set the crank so that #1 is at the top and the mark on the lower sprocket lines up with the oil pump. The cam shafts are what's important. Make sure the lobes on the #1 piston are oriented as I described for TDC. Of course the cam gears can only go on one way, and have the UP arrow, so it shouldn't be too hard.
06-09-2005, 05:23 PM
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Re: (PatrickGSR94)
and always...patrickGSR94 to the rescue. thanx pat. i was thinking too hard and didnt see the tree thru the forest. i should have thought about looking at the lobes and seen if they were open or closed on either end. i was way too busy trying to explain my question i never thought about figuring it out myself. thanx again pat and everyone else who got confused. 
06-09-2005, 06:42 PM
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Re: (98B00STED)
Just to add to Pat's response, you can also take off the dist cap while rotating the crank and when the button lines up with the corresponding "point" if you will, that cylinder is on the compression stroke, ie if the button is pointed around 7o clock and is lined up with that point, cylinder #1 would be on the compression stroke...
06-30-2005, 07:03 PM
#13
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ok i dont know if this is gonna help but,if the #1 cyl. is at TDC, take the dist. off and if the rotor is pointing at #4 spark plug wire then its on the exh. stroke...and something else ive learned is if the crankshaft is at TDC back it off a lil. this way none of the pistons are at TDC ...this way as the bring the cam to TDC you dont bend a valve
06-30-2005, 07:44 PM
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Re: (SniperRCivic)
its fairly simple...just simply look at your stock cam gear. You will see all the marks around them and one of them has a word "UP." That UP is supposed to be pointing upward and the crank pulley supposed to be at the WHITE mark at the crank...the easiest way to remember is to simply mark them with a pen...and that should be fine
07-01-2005, 06:03 PM
#15
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smkngsr you are right but what he was askin is how do you know when the crank is on the exh or intake stroke ...for every 1 time the cam turns the crank turns 2 time. once for intake once for exh.
07-02-2005, 06:35 AM
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Re: (AW)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AW »</TD></TR><TR><TD CLASS="quote">What if you have aftermarket cam gears i.e. Toda. Do they have the same marks to show TDC?</TD></TR></TABLE>
Not sure about toda cam gears, the gap between them seem to be a little bigger than standard aem degree. Im talking about the degree to adjust them
Not sure about toda cam gears, the gap between them seem to be a little bigger than standard aem degree. Im talking about the degree to adjust them
07-02-2005, 04:08 PM
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Re: (SniperRCivic)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SniperRCivic »</TD></TR><TR><TD CLASS="quote">ok i dont know if this is gonna help but,if the #1 cyl. is at TDC, take the dist. off and if the rotor is pointing at #4 spark plug wire then its on the exh. stroke...and something else ive learned is if the crankshaft is at TDC back it off a lil. this way none of the pistons are at TDC ...this way as the bring the cam to TDC you dont bend a valve</TD></TR></TABLE>
I doubt a human would be strong enough to turn the crank by hand such that a valve would bend. If a piston touches an open valve when you turn the crank by hand, it will just stop, and you'll know that you're touching a valve on one cylinder. Then you'll have to rotate the camshaft(s) in order to turn the crank some more.
I doubt a human would be strong enough to turn the crank by hand such that a valve would bend. If a piston touches an open valve when you turn the crank by hand, it will just stop, and you'll know that you're touching a valve on one cylinder. Then you'll have to rotate the camshaft(s) in order to turn the crank some more.
08-18-2014, 09:12 AM
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Re: how can u tell if TDC is on the intake or exhaust side?
I'm having a similar issue with my own D16Z6, and I'm wondering if it's okay to rotate the crank while the camshaft is at TDC?
08-19-2014, 08:38 AM
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Re: how can u tell if TDC is on the intake or exhaust side?
You're saying that it is ok to rotate the crank independently of the cam....as long as the cam is at TDC? Surely you jest. No...it isn't ok unless you're rotating the crank just a couple degrees to get it timed. Set the crank at TDC. Set the cam arrow pointing up and have the lines lined up. Put the T belt on. The reason you can't turn the crank freely with the cam at a single position is that you may interfere with a valve on another cylinder. This is why you smack valves when the T belt breaks.
Idk how much of an interference motor a D16 really is, though.
Unless the block is disassembled from the head. Then...why the hell would it ever matter?
Idk how much of an interference motor a D16 really is, though.
Unless the block is disassembled from the head. Then...why the hell would it ever matter?
Last edited by B serious; 08-19-2014 at 08:54 AM.
10-28-2021, 03:49 PM
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Re: how can u tell if TDC is on the intake or exhaust side? (98B00STED)
Scenerio:
1) Car comes in a with broken timing belt, engine only needs a new timing belt.
2) Rotate intake cam so arrow is up.
3) Rotote exhuast cam so arrow is up.
4) Rotate crank so arrow is aligned with notch on oil pump.
5) Everything is aligned and at TDC
6) Install the belt.
1) Car comes in a with broken timing belt, engine only needs a new timing belt.
2) Rotate intake cam so arrow is up.
3) Rotote exhuast cam so arrow is up.
4) Rotate crank so arrow is aligned with notch on oil pump.
5) Everything is aligned and at TDC
6) Install the belt.