Change in timing tension spring?

[awmccready]

A dealer told me that on the 97 Camry le 4 cyl, abs, auto trans, 5SFE engine, Toyota changed the timing belt tension spring. The new spring is gold instead of silver colored and is noticeably shorter than the original spring. The parts guy said that it may be due to a difference in the belt length, however, the new and old belts appear to be the same length, thickness, width.

When I installed the new Toyota timing belt, I used the same number of teeth, 65, between my camshaft and crankshaft marks that the original belt used. However, when I unloosened the tensioner wheel bolt, the crankshaft got moved counterclockwise from TDC, although the camshaft is still at TDC. The crankshaft movement appears to be one timing belt tooth. The only way I can see to move the crank to TDC and keep the camshaft where it is is to put 66 teeth between my camshaft and crankshaft marks.

The most important thing appears to be to get the crank and camshafts at TDC after tension is applied by the spring. However, I am concerned about not having enough tension on the forward part of the timing belt prior to loosening the tensioning wheel nut.

Has Toyota indeed changed the tension spring to one that is noticeably shorter? Should that cause the crankshaft to require one more tooth between it and the camshaft?

I have yet to rotate the crankshaft and re-check it. I had to install the lower timing cover to check TDC.

Or has the parts guy goofed? He double checked and got the same spring.

Any facts, opinions, suggestions would be appreciated.

[Pineapple]

The spring only change belt tension, won't do anything to belt length, timing, TDC.
The crank and cam shouldn't move at all when you put the spring on. You know you suppose to remove the spring before you put the belt on? You put the belt tight on opposite side to tensioner first. So its lose when you put tensioner on belt.

[awmccready]

Thanks for your response. It helped me reason this out.

For some reason, my manual says to put the spring on before the timing belt, but move the tensioner wheel as far as possible against the spring, then torque the wheel nut. That allowed enough slack to install the timing belt without having to force it. If I have to reinstall the belt, I will remove the spring first.

As you said, I did put the belt on the part away from the tensioner wheel first, i.e., the water pump then crank.

What you say about the spring not changing length makes sense. So, I rotated the crank two revolutions and checked the cam and crank again and they lined up at TDC. Apparently earlier, the cam had moved slightly with the crank, but not past the dimple on the camshaft seal housing.

It was apparently a false alarm. But I have another problem. After positioning the crank at 45 degrees and torqueing the tensioner wheel bolt, the timing belt is now sticking out past the edge of the camshaft sprocket about 1 mm. The belt moved there while I rotated the crank. Could this be due to the belt retaining washer behind the crankshaft pulley not being flush up against the belt? (I have not torqued the crankshaft bolt to specs yet.)

[awmccready]

Well, I pushed the belt back on the exposed wheels and sprockets, and then removed the pulley and used a small allen wrench to tap about 20 times around the big washer in front of the crankshaft sprocket. This didn't appear to do anything, but then I rotated the crankshaft 10 times and the belt moved back onto the camshaft sprocket where it appears that it should go.

Consequently, my problem appears to be solved.

[88 LE]

I don't know what you did wrong, but go and read this.

http://yotarepair.com/5S-FEtimingbelt.html

Did you install the washer (timing belt guide) correctly? The cupped side faces outward.

Forget about counting teeth on the belt. The alignment marks you need are on the crank pulley, lower timing belt cover, cam gear, and #1 bearing cap.

[awmccready]

Thanks.

I already had those instructions and a Haynes manual. I was aware of the cupped side of the washer having to face away from the sprocket. My instructions also told me about the timing marks for the camshaft and the crankshaft and I used those. The crank and cam were both at those settings.

However, since I had already painted the camshaft and crankshaft positions on the old timing belt, and since I have never replaced a timing belt, I thought I would double check against that benchmark, i.e., using the teeth count. That's how I first noticed that I had a problem with the tension on the radiator side of the timing belt. I think that problem would have eventually shown up as the crank being a few degrees past TDC, while the cam was still at TDC, after I rotated the crank several times to 45 degrees BTDC to set the upper idler pulley.

Although, now that you mention it (crankshaft washer cupped side out), that is a great double check to make before I torque the crankshaft pulley bolt and put everything else back together. I will definitely do that. If the washer is reversed, it might do lots of belt damage in a short time.

Thanks again for your time and your response.