I went through this same exact situation and frustration when doing my t-belt, it’s nice to know I am not the only one to have these issues.

I am making a repost of Meathead00 over in the SC430 forum, it’s valuable info!!!

Pull the spark plugs to make turning the crank easier.

-Do not remove the power steering pump.

-Do not remove the A/C compressor. On the “Stay” (the L shaped bracket on the right, lower side of the compressor) there is a nut and a bolt. That bolt needs to be removed because it screws into the Idler Pulley Sub-Assy #1. I had also unscrewed the wire clamp on the upper right side of compressor. That wire bracket sits on top of the compressor and it’s left most side is in the way of the Idler Pulley Sub-Assy #1. Some folks have had trouble removing the 2 Phillips head screws of the wire bracket and have instead bent the left side of the bracket to clear the sub-assy. I initially tried a screw driver but quickly realized I needed to use an old trick I learned. Use a Phillips bit and a small ¼ inch drive socket wrench. First tap the bit into the screw with a hammer, to get it to seat real tight. Then attach the socket wrench and break it free. I have found you can get much better leverage this way versus a screwdriver. I will say that when it came time to pull the Idler Pulley Sub-Assy #1 off, it was hitting the A/C pulley. For a minute, I thought I would have to move or remove the compressor. But if you angle the sub-assy just right, it will clear the A/C pulley.



Fast forward to the point where the covers are off the cams, and you can see the belt. I won’t talk about reusing the old timing belt. Personally, I think if you have made it this far you would be crazy not to install a new belt.



-Start with the engine in a perfectly timed position. The easiest way to assure this is to use the car manufacturers #1 cyl TDC timing marks. Make sure it is on the power stroke (TDC) and not BDC.

-Put the engine in a SAFE position, so if a cam or crank rotates while taking the belt off…no valves will bump into a piston face. To do this, rotate crank CCW by about 50 degrees. Why 50 degrees and why CCW? Every 90 degrees of crank turn puts another set of pistons at TDC. Right now at #1 TDC, #1 (and I think #6), are at TDC. So backing that off by about 50 is putting them back down into the cylinder roughly halfway…pretty safe. Would 45 work? Would 40 work? Yes, but 50 degrees is easy to see because at that point, the crankshaft v notch and key, will be at the 12 o’clock position. That’s the only reason I can think of as to why the manufacturer says BTDC vice ATDC. It’s easier to see that 12 o’clock position. If you chose to go CW, how would you reference that and be able to easily see where 50 CW is?

-Take the belt off.

* In my own experience, after having it at 50 BTDC, as I took the belt off, I started with the RH cam first (because it doesn’t have the front plate, you can slide the belt right off (with a little effort). I then tried to work CCW, but it was too hard (too much tension) on the crank sprocket, so I worked CW instead. Off the water pump then off the LH cam, and then finally off the cranks. At some point in the process (I didn’t readily notice when), I felt or heard the LH cam rotate CCW, like it was a spring unloading. It had rotated about 30 degrees! I was definitely not prepared for anything to move. Nothing in the manual or instructions about that potential. Later figured out it was because a combination of valve spring pressure (some are loaded up a bit) and the lobe shape of cams. It doesn’t take a lot of pressure for a cam to fall off a lobe.



-Install new belt. Of course it all starts with getting the cams and crank perfectly aligned at #1TDC. Use a 19mm wrench and get the cams at TDC marks. Put crank at TDC.

-#1. TRICK! Lock up the crank! After attaching the belt around the crank (CR mark on belt matched up to the dot on crank…about opposite to the key and v notch, put a socket with breaker bar on the crank bolt and position the handle of the breaker bar on some part of the engine bay that will prevent the crank from rotating CCW. Luck have it, I was able to rest the bar on the passenger side inner fender well. I also painted with white nail polish, a small marker on the crank pulley and block at the 12 o’clock position. I wanted something easy to see so as I was installing the belt I could easily glance at the 12 o’clock marks and make sure the crank wasn’t moving. Easier than bending down to see the oil pump dot, etc…

-Like the manual says, put the LH cam ½ tooth past TDC (CW), because trying to stretch the belt when the cam is at the TDC position is nearly impossible. I actually rotated the cam 1 whole tooth CW and was able to easily put the belt on with the LH CAM belt mark aligned to the correct cam pulley tooth.

*I think this is where the “T” mark on the cam housings come into play. I don’t think they stand for “timing.” I believe the symbol represents a valve, and that the “T” is a warning to not rotate past that point while the crank is at #1TDC. I think it is a safe marking. You could rotate cam up to it, but don’t go past it. There are 48 teeth on the cam sprocket. Divided by 360 degrees, each tooth on the cam represents 7.5 degrees of cam rotation. From #1 TDC, there are 2 teeth to get you to the “T”, 15 degrees of cam rotation. That amount of rotation of the cam shaft will not give enough valve lift to force any valve into the face of a piston that is at TDC. I think 15 degrees of cam movement results in about .08 inches of lift. Obviously all this depends on the cam lobe geometry. So, that’s what I think the “T” is for, just a warning mark about valve interference.

-With the belt on LH cam, take your 19mm closed end wrench and gently tap it CCW, back to the TDC position. Wrap the belt around the water pump pulley, and then as you approach the RH cam, “sproing!” The LH cam just rotated CCW about 2 teeth, the belt staying still because the crank is locked in. The belt and LH cam are no longer aligned. Damn! That slight CCW tension I put on the belt as I routed it towards the RH cam was all it took for the LH cam valve springs to overcome the cam lobes and pop CCW those few degrees. Long story to get to the second trick.

-When the LH cam is all set and back to TDC with the belt exactly where it needs to be…TRICK! Lock up the LH cam! I used one of those big plastic work clamps and clamped the belt to the cam, kind of at the 11 o’clock and 5 o’clock position. Now you have the crank and LH cam locked together!

-Same deal with RH cam. Rotate it 1 or 2 teeth CW, put the belt on it and then on the tension pulley. The belt is completely routed. Then wrench the cam CCW back to TDC.

TRICK! Lock up the RH cam! Put a clamp on the RH cam. Better to be safe than sorry.

-With everything locked up at exactly TDC, attach the hydraulic tensioner device with its 2 bolts. Alternate between the 2 bolts, take your time. You want the device to seat squarely in the bore of the pulley assembly, it will start to put a little tension on the belt as you screw the bolts in. Torque to 19ftlbs. Then finally, pull the pin! Grenade!!



That was it. Went smoothly. Nothing shifted.



Notes:

-The permanent timing marks are all for the #1 cylinder. For the crankshaft position, you have the “dot” like protrusion near the oil pump, and the “v shaped notch” on the rear end of crankshaft sprocket. When the notch is aligned to the dot (which is at about the 2 o’clock position), the crankshaft is either at BDC or TDC.

-A brand new belt has 3 markings on them. They exist because there are an exact number of belt teeth that must go between each of the mounting points on the cams and crank. Between the two cams, RH, around water pump, to LH, there are 71 teeth on the belt.

-You probably knew this, but I didn’t!

With the engine absolutely at #1TDC, not a hair off, I put my new timing belt on, with the manufacturers marks on the belt (RH Cam, LH Cam and CR) exactly where they needed to go. I released the hydraulic tensioner and now with the belt taught, everything stayed exactly where it was supposed to! There’s a cool trick I used that I’ll mention later, but here’s the deal. When I then turned the crank 2 full revolutions to confirm everything was in fact as great as I thought it was, when I reached #1TDC two crank rotations later…the marks on the belt were no longer there! Holy crap I thought, I just screwed everything up. What happened to the belt marks!! I kept turning the crank, still no belt marks. Oh, there they are, I see them, going around the water pump pulley. Kept turning, watching the belt marks navigate their way around the loop. I stopped counting crank turns, and eventually the belt marks made their way, 1 full lap around the track, back to starting position…but they weren’t pointing at the CAM pulley timing marks anymore. Took me many moments of mental anguish to figure out that this is a geometry/math phenomenon. Crank pulleys have 48 teeth, crank shaft has I don’t know how many, and the belt has a couple hundred teeth. There’s probably some astronomical magical formula for figuring out how many crank turns before the sun, moon and Earth align. Point is, it doesn’t matter as long as you installed it correctly, it has the right tension on it and of course that it is the right belt.