Hey guys, noticed my timing belt is a little loose, I did a head swap with out removing lower timing cover but it was tight when I initially had everything back together. Can I tighten the tensioner without removing the cover?

97 civic ex coupe d16y8 222k

 

What I use is a sturdy "5 gallon bucket" handle to pull the tensioner bracket upwards while tightening the 14mm bolt. You basically bend the metal rod into a hook on the end. This is more sturdier than a coat hanger.

 

Never had to do that before, metal handle and all. The tensioner spring is suppose to do that for you? You tighten/adjust the belt as if you just installed it the 1st time.

 

The trick to putting more tension on the belt is to use the valve-spring pressure. Set the engine to TDC-1 and remove the rubber plug in the lower timing cover. Next loosen the tensioner bolt. Now rotate the crank forward several degrees until you feel the valve springs open (gets hard to rotate the crank). This puts the max amount of belt slack on the tensioner side of the timing belt, where the tensioner-setting-spring can now remove it. Now the trick to finishing the job done is to hold the crank against this valve-spring pressure at the same time as you tighten the bolt on your tensioner bolt. Once the tensioner bolt is snug, let go of the crank and finish torquing your tensioner bolt properly (use your torque wrench). Put the rubber plug back in and you're done.

Don't go nuts rotating the crank with the tensioner loose. Just roll it forward until you feel the valve springs open. If you go crazy and end up skipping a tooth you will have to pull the valve cover & timing covers to re-set your timing belt.

 

I've done this many times and nothing happens....and works every time.

 

How do you hook onto the tensioner bracket without removing the lower timing cover?

 

This is a very detailed and informative explanation of the Factory Service Manual (FSM) method of timing belt tensioning.

Very helpful for understanding of what is going on when following the FSM.

Thank you for this contribution.

 

I was thinking this might work but didn't know for sure, will do it tonight, thank you :D

 

There is such a thing as too tight. If it is too tight, you will hear a loud whirring noise from the belt and likely shorten its life. Also if you find your timing belt has become loose during use, it may be time to replace it.

The spring is all you should need. Remove upper cover. Loosen the tensioner bolt through the hole in the lower cover. Put a wrench on the cam sprocket nut and turn the cam clockwise to pull all the slack out of the front of the belt. Hold it under tension while you tighten the tensioner bolt. The bolt needs to be really tight before starting the engine.

 

This won't work correctly! Your method will ONLY be pushing the cam directly against the valve springs. You will NOT be generate ANY tension on the front of the belt. Remember, there is nothing holding the crank steady (crank spins freely without valvesprings). Just do it the service-manual way by holding pressure on the crank as I posted. The valvesprings do the tensioning on the front, and the tensioner spring sets the tension on the back.

 

Now the back is nice and tight but the front is looser. Let the car run for a bit, too. I guess one side is supposed to be looser. Can't fit a torque wrench down there so I have no idea how long it will hold.

 

You can access the bracket from on top.