hoosier58

Hey everybody! I need some help again. My water pump, cam and crank seals, idler pulley, and new timing belt are installed. I ended up buying the Schley tool, and torqued the crank and cam pulleys yesterday. Today decided to put the rest of it together.

Now I wonder if anyone can provide me the various drive pulley diameters, because I think a PO got 'creative' with this car some time in the past.

Actually, I KNOW someone got creative in the past, because the alternator on it had the oval plug instead of the round one (which the wiring harness has). They jumped three wires from an oval plug and crammed them into the female round one in the harness. I discovered this a week or so after buying the car, so added blade connectors to the wires and have been driving it that way ever since. I also had charging issues back then, and the drive belt was slipping. I noticed that the arrow above the tensioner was not between the tick marks on it, so bought a serpentine belt about 1.5 inches shorter, and have been driving it that way too.

Then I had the water pump go out just as I was getting ready to sell it (the very evening of the day we bought my daughter another car with better gas mileage). I immediately ordered a water pump online, and also an alternator, thinking I should do that too. That was before I knew how much was involved in the water pump replacement. After the parts arrived, I realized what was involved, so decided to do a timing belt and seals too, hoping to make the car worth more because of these major things being recent. I also decided to fix other issues, to raise the value a notch.

Then I got really busy at work and the car was parked for a while, though I did visit a U-pull once in a while, found good seats, replaced a door lock actuator, and did some body work needed, because my daughter had rear ended someone. Early in October I got everything needed for the timing belt, and started that a little way into the month, but then had to work on a van for my other daughter instead. Yesterday I finished the water pump and timing belt, other than final reassembly .... or so I thought.

Today I installed the covers, the serpentine tensioner, the alternator, and the water pump pulley, fan clutch and fan. I bought a new serpentine belt, thinking I would need one because I had the shorter one on with the other alternator. When I went to install it, it was too long. I could slide it on w/o even using a wrench to retract the tensioner. I also realized that the cheap alternator I ordered was wrong. The front of it is too large, and it places the pulley almost 1/2" too far forward to align with my other drive pulleys. The grooves in my pulleys, because of their depth, also made me look closer at my crank pulley/harmonic balancer, which has little ripples, but no ridges. Having nothing to compare it to, I searched online for images, and found the crank pulley should have more distinct ridges, and should also have a shoulder rim on the front. Mine doesn't.

So, now I'm resigned to buying another harmonic balancer ---- $60 on eBay --- and another alternator --- not as cheap. But I still need to figure out why my drive belt is too long. I don't know if whoever put that other alternator on also swapped out another pulley, or what is going on. I really need the diameters of all of the pulleys that the serpentine runs around to figure out what else I need to do, and I can't find the information anywhere.

If someone that has an early SC300 (mine is a 94) has the time to measure all of their pulleys, it would REALLY help me out!

I need the sizes of the alternator pulley, the harmonic balancer pulley, the power steering pulley, the water pump pulley, and the A/C pulley, The tensioner pulley might be nice too, in case the wrong one of those is on my car.

Thanks in advance, if anyone can help me.

Maserati

iTrader: (1)

If you could visit a u-pull and maybe if a car has a belt on it, you can measure that? Where did you order your previous parts from?

hoosier58

I can't remember where I ordered the alternator. It was months ago, and that's when I thought a water pump was an easy job (like on an American V8), so I ordered whatever was cheapest. I thought if I could get it running I'd sell it for $1500 (obo), "as is". It wasn't until I realized I had to do all of the labor of a timing belt that I decided to improve the car and try to raise the value.

The U-pull I use has only had two SCs at the same time once in the years I've gone there. When getting stuff like seats, emblems, lock actuators, regs, hood/trunk shocks, etc., I can pull them off of an SC4 as well as an SC3. Right now, they have one SC400, which won't help me figure out what my various pulley sizes ought to be.

hoosier58

Well, I drove out to a dealer today that had a 94 SC3 on craigslist, and measured the various pulleys. I'm really scratching my head on this one.

The alternator I bought, that I already know is wrong because the front of it is too big, has a pulley about 2.5 inches (measured at the shoulder). The SC3 I measured today has a pulley about 2-13/16 measured at the shoulder. I'm stuck with this wrong alternator, because I can't find any paperwork from when I bought it. I suppose I can sell it to someplace that buys cores, but that seems like a shame, because it is brand new. I did start thinking that maybe it is actually for a SC400. It does have the round Lexus plug. It fit the mounting points for the 2jz-ge, but the front part of it is about 1/2" longer, which puts the pulley out of the same plane with all of my other pulleys. A correct 2jz alternator will be about 2-1/4" from the place it contacts the engine for the top bolt to the back of the pulley. This is about 2-3/4". If anyone around Denver wants to try it on their SC400, pm me. It's your if it will work for you.

Here's the puzzling part though. My crank pulley (HB) doesn't have a shoulder on the front edge, and the surface the belt runs on is worn to the point that it has ripples more than machined ridges. How could a rubber belt do that to a steel pulley? I measured it this morning (all of these measurements were done with a carpenter's tape, so they're approximate), and wrote down 4-1/8". The SC3 I measured at the used car dealer had a shoulder on the crank pulley, and the measurement was 5-7/8"!
That's a HUGE difference!
It was too dark to check my earlier measurement when I got home, but I don't see any way, even if I wrote down something 1" off, that my SC300 can have the correct crank pulley on it. That's just weird. Who would put the wrong harmonic balancer on a car?

hoosier58

I'll continue to update this, in case it may help someone in the future.
I ordered a replacement harmonic balancer on eBay. Toyota ones were available, but pretty pricey. There was an aftermarket one for $59, and another one for $75. The pictures weren't great, but I zoomed in to look them over. I tried to visually compare the ratios between the various planes. After looking things over, I decided on the $75 one. It looked much more like the Toyota one.
I may have also figured out the strange, worn one that is on my car. The $59 one on eBay, when comparing ratios, does look like it might have a smaller diameter at the pulley. It also has a thinner, smaller shoulder on the front. of the pulley. I can't say for certain, of course, and this still doesn't explain how a rubber belt would wear away a steel pulley, but I think my car may have a very worn example of that cheaper aftermarket HB. If you need to replace yours, I would avoid that one.

hoosier58

My $75 aftermarket harmonic balancer matched the measurements I took from the 94 SC3 at the used car lot. I pulled the strange one off and replaced it today. Looking at them side by side, I could hardly believe it! It looks like about an inch wore off of my HB!

I did shoot the old one with some rattle can paint while I had everything apart earlier, but you should still be able to see the radical difference between the two. The dark blue one is the old one, and the black one the replacement: