1st & 2nd Generation (1983–1986 & 1987-1991)Toyota Camry Discussion for years: 1983-1986 & 1987-1991.
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Trying to install a timing belt on a 91 Camry 3S-FE motor, Haynes manual states to put the inspection hole (on cam sprocket) at the top. Align the inspection hole with the mark on the cam bearing. I have what appears to be 3 different marks on the cam bearing. One is a raised area, one is a vee notch and one is a punch mark. Which of these marks am I looking for? I have turned the cam pully to line up with the punch mark but I'm now at the 11 O'clock position instead of straight up. The vee notch mark is closer to straight up. So which mark am I after? I have not counted but it appears they are about 4 teeth on the cam sprocket apart (the Vee and the punch marks)
Thanks, Then why does the illustrations in both Toyota service manual and Haynes show a circle (Punch mark) inside the inspection hole instead of a verticle line (vee notch)?? Do you see where the confusion comes in?
I am having difficulty with this also right now. In order for the camshaft pulley TDC mark to be straight up, it is lined up with the vee notch, not the punch mark. Which is it?
Hi. I'm new here. I found this forum while searching for the same thing: which of the three marks in the cam bearing cap gets aligned with the hole in the upper timing (camshaft) timing belt sprocket. I thought I had it nailed when I chose the more obvious of the three marks, the notch. Put the 90 Camry back together and it started and idled well. But had absolutely NO power.
So today I took off the upper timing cover and was going to check the belt timing. From what I'm reading here, I should have aligned the hole in the sprocket with they tiny punch hole, not the more obvious notch. In other words, the first timing mark the pulley holed "comes to" as it rotates clockwise.
Is that correct?
If you look at the second picture posted by 88LE, you will see that the engine appears to be sitting up "straight" like it was sitting on the garage floor, as opposed to the "leaning rearward" position the engine has while in the car. I have seen this "leaning" throw off new techs when trying to decide which mark is correct. Just realize that as the whole engine is tilted backward for proper installation, the "top" or 12 o'clock position tilts back along with the engine.
If you look at the cam sprocket in that second picture, the hole is at the 12 o'clock position, and the mark in question is directly behind that hole. The mark is on the bearing cap, in a position that is perpendicular to the parting line of the bearing cap. To put it more simply, if the bearing cap was sitting on a table in front of you, the mark to use for timing would be at the very top of the bearing cap, and it would face the hole in the sprocket when installed.
Toyota is not the only company that has an occaisional disparity between what is shown on a drawing (from which the manuals are derived) and the marks actually applied to the finished parts during production. Just let the apparent position be your guide, and compare two different sources of illustrations if you can. At least one timing belt manufacturer markets a book with procedures and pictures for changing timing belts.
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Last edited by timebuilder; 12-17-2006 at 02:17 PM.
If you look at the second picture posted by 88LE, you will see that the engine appears to be sitting up "straight" like it was sitting on the garage floor, as opposed to the "leaning rearward" position the engine has while in the car. I have seen this "leaning" throw off new techs when trying to decide which mark is correct. Just realize that as the whole engine is tilted backward for proper installation, the "top" or 12 o'clock position tilts back along with the engine.
If you look at the cam sprocket in that second picture, the hole is at the 12 o'clock position, and the mark in question is directly behind that hole. The mark is on the bearing cap, in a position that is perpendicular to the parting line of the bearing cap. To put it more simply, if the bearing cap was sitting on a table in front of you, the mark to use for timing would be at the very top of the bearing cap, and it would face the hole in the sprocket when installed.
Toyota is not the only company that has an occaisional disparity between what is shown on a drawing (from which the manuals are derived) and the marks actually applied to the finished parts during production. Just let the apparent position be your guide, and compare two different sources of illustrations if you can. At least one timing belt manufacturer markets a book with procedures and pictures for changing timing belts.
Thanks for the reply. I understand the fact that the engine tilts to the rear. However, I keep reading different answers to the same question: Which timing mark's the right one? Is it the round punch hole or the notch, which is more akin to a chisel mark. Even taking into account the tilt of the engine, it seems the notch is the right one. But then others say it's the first mark the pulley hole comes across, the punch hole.
When I first did the job, I lined up with the notch. Now I realize that, while that might have been the right mark, the darn cam pully moves clockwise when the tensioner takes up the belt slack. So I'm now sure the timing got knocked off about 10 degrees during my first attempt.
So now I have two problems: Which is the right mark and how do I keep the upper sprocket from moving once the belt tensioner is released?
PS: I'm trying to do this, the second time, without removing the bottom timing cover. I don't see why it shouldn't be possible.
This is a post I made recently that might be helpful. The condensed version is that the ONLY mark you need to concern yourself with is the one at the top of the bearing cap, and that is the mark that will be properly aligned when all is tightened down. This means you have to try and "predict" how much the relationship between the cam and crank will change when the slack is removed when you rotate the crank. Make the belt positioning adjustments one timing belt "tooth" at a time, unless you can see that you are "way off." In a few minutes, you should be able to turn the motor using the crank, stop at the "0" mark for the crank, and have the hole in the cam sprocket line up with the mark at the top of the bearing cap. I take out the plugs to make all of this easier, but if you don't have shop air with a blowgun available to blow any dirt out of the plug tubes before removing the plugs, then get a can of air at Staples and use that. You don't want junk falling down into the cylinders when you take the plugs out.
Try these steps:
The mark you want to have aligned with the hole in the cam sprocket is the only mark that is at the "top" of the bearing cap. Remember, the whole engine "tilts" toward the rear, so look for the mark being perpendicular to the parting edge of the bearing cap.
When the hole in the cam sprocket is aligned with the mark, and all slack is removed from the "front" part of the timing belt (closest to the front of the car) the crank pulley timing mark should be lined up with the "0" on the lower timing cover. I like to have the plugs all out when I check this, so I'm not fighting compression as I crank the motor by hand. I like to use a socket on the crank bolt, and an extension with a ratchet to turn over the motor with a sense of control. The longer the ratchet handle, the more control.
When the cam and crank are lined up as described, and there is no slack on the "front" side of the belt (that's the part of the belt to your right, when you're facing the end of the motor from the passenger side fender) the distributor rotor will be lined up under the number one spark wire connector.
Also, look at page 71 in your Haynes book. The US motor has an "E" with a hole, and that is the timing hole. The Canadian motor has the "E" 180 degrees away from the top, and there is no hole near that "E." Also, the #1 piston is at the top of the cylinder when the crankshaft keyway faces the ceiling, and/or when the pulley timing mark is at "0."
Double check the relationship of the timing marks by cranking the motor two revolutions by hand, stopping the crank pulley groove at the "0" mark on the lower cover. If the hole in the cam sprocket is not lined up with the mark on the bearing cap when the crank pully is lined up at the "0," then retract the tensioner (press it against the spring to the end of the adjustment slot and tighten the bolt) and move the cam sprocket a little bit forward of the mark, replace the belt (or jump it a tooth to remove slack) release the tensioner so the spring holds tension against the belt, turn the crank forward (clockwise) 2 turns and check the marks again, stopping at the crank "0" mark. If the marks are good, tighten the tensioner bolt. If not, figure out which way the cam sprocket has to move so that the you are settled on the marks after the two turns, turns made with the tensioner bolt loosened so it can move a little and press against the belt while you turn the crank pulley.
If you have to jump a tooth with the belt to correct the timing, you’ll have to push the tensioner against its spring and tighten the tensioner bolt again, first. This “retracts” the tensioner and holds it from pressing against the belt. Never pry on the belt with any kind of tool, because you’ll snap the internal construction of the belt.
Sometimes, you'll over-estimate the belt slack amount and go too far forward with the cam sprocket during the setup process, but you will quickly figure out what you have to do to get those marks lined up. Since this isn't an interference motor, you're pretty safe. There is very little "give" in a timing belt, and the cam sprocket doesn't have to be set too far forward of the mark when placing the belt into the sprocket teeth. If you do it right, as soon as you rotate the crank the slack is removed and the cam and crank are now in sync, and the cam sprocket mark will line up with the hole when you stop at the timing mark “0” on the lower cover.
After you have done this a couple of times, it makes more sense than reading it on paper or a screen. Remember, the front side of the belt is the part under tension, being driven by the crank. The tensioner is controlling the slack on the back side.
Fredk, believe me: I DID "read above." Several times. However, while you say we should use the little punch hole, not the longe notch, this creates several problems. The punch hole matches up with the hole in the upper timing sprocket at about 10 oclock, even taking into consideration the tilt of the engine. The larger notch meets the sprocket hole at what seems much closer to straight up (but tilted).
Also, on another Toyota forum, somebody said the mark to use is the one about 1 mm long and .5 mm wide. This describes the notch I'm talking about (the middle of the three marks) not the punch hole.
I've done it about ten times on my Camry. It's got 515,000 miles. It's the punch mark.
515K? That's amazing! I was just given this 90 Camry. It has 220K and I want to fix it up and give it to my daughter. So far, I've spent about $300 on new belts, water pump, two tires etc. But this timing belt job is getting to me! Not only was I stymied by the choice of three timing marks, but I can't figure out how to keep the top pully from moving when I let that tensioner tighten the belt. Spent all day on it today!
So, tomorrow, I'll try again. I started today aiming for the punch hole you mention. Then, after reading another forum where they said to use the notch, I switched back to that. I can't seem to nail either one because that top pully turns when the belt tightens.
Thanks for your help!
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