2001 GS-R: Engine rebuild, other refreshments

[Dave7CDMTYPER]

I'm working on the timing now. Was able to torque the crank pulley bolt. I'm a little uncertain about some things. The cam gears are generally at TDC, but they aren't both at exactly the same orientation in terms of the their markings. The intake gear is a little to the left. But these positions seem to be how they want to sit (when I was adjusting them without belt on).

I tested the timing by rotating the crank pulley counter clockwise several times. It seems to rotate smoothly with no evident interference. Does that mean it's ok?

Also I'm trying to add tension with the tensioner. I followed the FSM instructions, but it didn't seem to make any difference in the tension.

I'm wondering if these things are all generally fine. And when I take the car to a dyno shop, will they be able to adjust the timing if needed? I know cam gears are adjustable. But as far as I can tell it wouldn't be too hard to adjust the timing belt when the engine is in the bay.

[shuttlepilot]

Can I suggest looking at page 6-12 of the 98 service manual. Although it is in the B18B1 section, It shows using pin punches to lock the cams at TDC using holes through the camshaft holder/overhead oil galley plates . I know the factory cams have holes to allow punches to lock the position. Looking at TODA's page, I don't see holes in their cams so this may not work. I haven't used the punches method myself as I do the marking transfer method, but noticed they are there as a possible assembly aide.

2-10-2025 11-03-20 PM.png (254.09 KiB) Viewed 8598 times

Alternately, there are marks on both sides of the cams at 3 and 9 o-clock so you can run a straight edge between the two cams to level the hash marks out in a line. That is probably what the designer intended. Here is what my alignment looked like on my car

2-10-2025 10-55-16 PM.png (852.94 KiB) Viewed 8599 times

[Dave7CDMTYPER]

Can I suggest looking at page 6-12 of the 98 service manual. Although it is in the B18B1 section, It shows using pin punches to lock the cams at TDC using holes through the camshaft holder/overhead oil galley plates . I know the factory cams have holes to allow punches to lock the position. Looking at TODA's page, I don't see holes in their cams so this may not work. I haven't used the punches method myself as I do the marking transfer method, but noticed they are there as a possible assembly aide.
2-10-2025 11-03-20 PM.png


Alternately, there are marks on both sides of the cams at 3 and 9 o-clock so you can run a straight edge between the two cams to level the hash marks out in a line. That is probably what the designer intended. Here is what my alignment looked like on my car

2-10-2025 10-55-16 PM.png

Thanks very much for posting. I did learn recently about using the punches, and I do have 2 5mm. I don't think the Toda have the holes for this method (would be nice), but I'm going to go back to my shop today to work on the timing. I am aware my timing is not correct and will definitely be figuring this out until it is correctly done.

Thanks for posting that photo, it does help and I understand that the cam gears need to be lined up with the horizontal lines at 9 and 3 o'clock. I see how you did your timing belt with the lines in the top middle and marked the belt with white marks. I'll do that too.

I also need to find torque specs for Toda cam bolts, and the adjustable screws.

[Dave7CDMTYPER]

Alright, I think I'm getting on the right track here. Today I torqued the cam bolts to OEM spec, and torqued the Allen wrench Toda bolts to 10 ft lbs, which is within the Toda spec.

I got the cam gears to be pretty much level, looking at the horizontal lines, to be lined up horizontally with the block and each other. And the timing marker on the crank gear is lined up with the oil pump marker.

The timing belt seems a little loose in between the cam gears. But maybe that is normal, and will adjust properly when I tension the belt? I got the belt about as good as I can. I'll torque the crank bolt back on maybe tmrw and and see how things are. Really excited to keep moving forward and do the valve adjustment etc.

[Dave7CDMTYPER]

Thanks in large part to DC2 Productions text support, I got the timing belt tensioned correctly today. The timing marks look good. Got the timing covers on. Next up, valve adjustment!

Learning how to do the timing belt correctly was a process, but now I understand it much better.

[shuttlepilot]

I'm a bit late to this, but here is my input for another POV. For tensioning the belt, I strongly suggest following the manual exactly, with the addition of tightening the tensioner pulley bolt while you are going through the stroke of turning the motor over as instructed. That way you capture the tension state while in motion. I think the book explains that part really poorly because when you stop turning, and then tighten the tensioner bolt, some tension is lost. When you tighten the tensioner pulley down while turning the crank, you are tensioning the all the items in the timing gear train at its running state. Be sure there is no spark plugs in the engine to introduce inconsistent resistance from compression when doing this.

I would highly advise against following what some of the youtubers suggest by turning one of the other gears to get it tensioned for convenience, or adding extra tension by holding the intake cam while pulling on the crank pulley. The risk of overtightening it if tensioning with intake cam gear is higher. It may feel good, that you got it tighter, but you have to take into account expansion of parts when heating up may not be enough to free run and early wear of the cam on aluminum bearing surfaces from running a belt with higher loads. If the engine is a race throw away, that would be fine, but I am leaning towards the lighter end of acceptable tension to do the job to minimize wear and get more time from my motor.

The same lower end of acceptable tension applies when tightening the accessory belts. The Denso tool listed in the manual is highly recommended and has proved invaluable in setting tension slightly below the average of the range. That way I know it is not wearing down the bearings of these parts early, introduce leaks (eg pwr steering) by pulling the shaft too hard in one direction, or soaking up power. Our alternators are supposed to survive high rpm operations so I certainly don't want to burn through bearings prematurely on those items either.

[Dave7CDMTYPER]

I'm a bit late to this, but here is my input for another POV.

Thanks very much for posting. This has been a fun learning process for me. It's only with firsthand experience that I get to now understand these types of things, such as doing the timing belt etc.

You make very good points. I definitely utilize my factory service manual a lot for this project. I have read through and attempted the timing belt tensioning steps. When I do the thing where after rotating the crank several times, then put at TDC, then rotate crank 3 cam teeth counterclockwise and tighten tension bolt: I see the tension spring compress a little bit, meaning it is adding tension. But this doesn't seem to be quite enough tension. The timing belt in between the cams seems too loose.

So I did the trick where you take a flathead screwdriver and push up the tensioner a little bit (not all the way). I don't want the belt to be too tight of course, but this does help to add some tension that I think is needed. It seems to me that the FSM tensioner instructions doesn't add enough tension.

[JDMJNKY]

Looks like you got the slack out, good job!!!

I was feeling creative today, so, I made this JIC anyone has a future struggle.

https://youtube.com/shorts/QmKQzmfOoaI? ... __3QYgar7B

[Dave7CDMTYPER]

Looks like you got the slack out, good job!!!

I was feeling creative today, so, I made this JIC anyone has a future struggle.

https://youtube.com/shorts/QmKQzmfOoaI? ... __3QYgar7B

Thanks man. I clicked on that video link, but it says it's private. Can you make it public or?

[JDMJNKY]

Absolutely. done.