replaced timing belt, question... - Honda Prelude Forum

munscher · 05-11-2005, 08:27 PM

Well I'm almost done but I can't seem to get the cams to line up perfectly. With the flywheel at TDC, this is what i'm getting right now...

Now, it seems off obviously.. almost like i need to adjust the intake cam by one tooth. The thing is, if i turn the intake cam clockwise to take up the little bit of slack in the timing belt b/w the two cams then they ALMOST line up, but still not perfect.... SO, in turning the crank counter-clockwise to TDC, should it line up exactly then? with no need to take the slack out? Seems like everytime i think i've got it figured out, its just a little bit off in one direction or another. Is this supposed to be perfect? or is there a little bit of play in there due to the belt? (I tensioned the belt according to Helms instructions)

Also, I lined the front balancer pulley as best i could with the alignment arrows, but man thats a ***** when its in the car! My balancer belt still looks kinda loose to me even after i adjusted the tension per Helms instructions. I noticed that it was equally as loose before i took the old belt off, is this normal?

I replaced both belts as well as both tension pulleys/springs.

Everything is together as of now but i'm waiting til tomorrow to crank it up... and waiting to see what you guys have to say. I just need someone with experience to give it the go ahead, i'm always nervous about these things.

munscher · 05-11-2005, 08:35 PM

Oh, and it definately needed changing... there were belt shavings all over the place inside there and it had obviously been rubbing the cover as well.

Gerhard · 05-11-2005, 09:10 PM

We did mine when the engine was outside of the car... and that was a pain in the ass.

However, we did use a kevlar timing belt.... so I will not need to replace that any time soon... They are supposed to last for the life of the car, but it's the other parts like the water pump, balancer belt, and auto tensioner I'm more concerned about.

Anyway... with all of the trouble you are going through... I highly recommend you replace the water pump, balancer belt, and the auto tensioner while you are there. Get the latest part for the 5th gen tensioner and you'll be very happy.

In so far as the answer to your question, you need to line everything up again. Then you need to turn the whole thing one revolution to get all of the slack out between the two cam gears (counter clock wise). Things should line up without a problem, and you want to use a straight edge of some sort with the two hash marks on the pullies that face each other. (Like your picture above.)

They do make a tool that holds the two cam gears together so they do not more in relation to each other, Joon525 has one.

They also make a tool that slips into the intake cam and creates a beveled edge to slide the timing belt over so that the cams don't move due to excessive force needing to be applied.

munscher · 05-11-2005, 09:21 PM

Yeah, i replaced the water pump while i was in there (forgot to mention that). I also replaced the tensioner pulleys and springs (h23 is manual however, not auto).

I can keep the two cam gears stationary at TDC by placing a "5mm pin punch" (a T20 torx driver in my case) through the bracket and into the small hole in the camshaft as outlined in the Helms. The only problem with this is that I can't get the belt on while they're locked into that position... they're like 1/2 a tooth off, so i either have to spin the crank half a tooth or spin the cams half a tooth each. (This is a common problem from what i've read and i've seen a couple procedures to try to overcome it.) But in any case that shouldn't allow one cam to move in relation to the other. I'm not sure what point i'm trying to make anymore... but also, i did tension the belt per Helms instructions and then made one whole revolution back to TDC before taking that picture.

Gerhard · 05-11-2005, 09:33 PM

Yeah, I've got an H22A... so it's a little different... but not much.

The key is getting the belt on without letting anything more... the ring tool that slides into the intake cam would solve your problem.

hawkze_56 · 05-11-2005, 11:59 PM

The best way that worked for me was actually making small marks on the TB that show where you want the arrow on the cam gears to be once it's all tight. Then just put it together according to those marks and you don't have to guess and **** around....it's hard to explain....

Joon525 · 05-12-2005, 05:23 AM

What you need to do is redo the whole thing or lock the tensioner, slip the belt off and do the following....
With the belt off of the cam gears you need to put a socket on the intake cam and have a friend rotate it clockwise a little and then you slip the belt on. Without the tension from the belt the valves will want to push the cams a certain way. Basically you anticipate the cam advancing a little so you retard it a bit.
I make mention of this in my write up.
Write Up: Timing belt, cams, cam gears, thermostat, fan switch

munscher · 05-12-2005, 07:28 AM

hrm, i remember reading that writeup... and i just re-read the installation of the belts section and see no mention of this. I must be missing it.

So leave the exhaust cam at TDC and turn the intake cam "a little" clockwise. What is "a little?" I'm assuming just enough to match up with the teeth, since TDC seems to match a peak with a peak instead of a peak with a bottom.

But in any case3, the intake cam is off a little and we all agree on that, haha... back to work i go.

munscher · 05-12-2005, 07:59 AM

OH yeah, just to be sure, the marks on the flywheel.... I'm using the white CROSS as TDC, there's also a line with a red '15' next to it and then another line beyond that. All lines are in white, but the cross (+) is TDC, correct?

hawkze_56 · 05-12-2005, 08:54 AM

YES!, use the cross. I learned that lesson the hard way...

munscher · 05-12-2005, 03:42 PM

finished it up earlier today, got it aligned perfectly. Was still a little nervous starting it up, but it runs 10x better than it did before. Thanks for the help.