TIMING BELT TENSION (loose-then-tight-then-loose cycle)

[miked]

Hello guys,

About a month ago i changed the timing belts (A & B) of my 4d56T engine.

I checked the tension of timing belt A a while ago and deflection is approx 10 mm deflection. The manual says 5 mm max limit. As i depress the belt, the injection pump sprocket moves a little. The Tensioner is tight. By judging the starting, idling and acceleration characteristics of the engine, there is nothing wrong.

Still, i decided to retighten it. I did it by the book (manual).

As i checked the whole length of the belt for about 1/4 turn at a time, the belt becomes loose and then tight and then loose again and so on....IS THIS NORMAL?

But all 3 sprockets are still in time after i did more than 3 rotations by the crankshaft.

here are the steps that i did:
1. Align at TDC.
2. Loosen tensioner pivot side then slot side.
3. Rotate timing belt by 2 teeth of the camshaft.
4. Tighten tensioner slot side first then pivot side
5. Rotate ccw to TDC (2 teeth of camshaft back)

After the re-tensioning, the loose-then-tight-then-loose cycle is still back but the deflection is somehow decreased. any idea?

[lexxus]

normal lang naman yan sa timing belt na lumalaki ang belt tension tapos yun tensioner niya ay hinde naman automatic tension kaya mangyayari yan sinasabi mo tama naman ang procedure mo sa paghigpit ng tension..
yun sa galan na v6 ay automatic tensioner kahit na luma na yun belt hindi nagbabago yun tension ng belt..

[miked]

thanks for the input lexx. malamang dahil sa hindi automatic yung tensioner nya.

akala ko may namiss ako na step during my installation last month.

i'll still check it monthly. if it comes loose again then i think i have to change the tensioner spring. i hope not. sana.