This weekend I did a water pump/timing belt/tensioner pulleys/balancer belt change on my girlfriends 99EX 4 cyl. When I got to the point where I was taking the tensioners off, I noticed that something wasn't right. I couldn't figure out what the hole on the timing belt tensioner was for. I didn't see anywhere to put a fastener or a pin. So upon closer inspection and refrencing these forums, I realized that there should be a pivot cast into the oil pump cover. But it looks like the pivot had been sheared off. It wasn't in the plastic belt cover, or anywhere on the floor. I have no idea why it would be sheared and missing. I ended up having a friend tighten the nut that held the tensioners on while I applied some pressure from underneath to tension the timing belt. It seems to have worked ok. The belt was tight enough that I could not twist it more than halfway. I drove the car around yesterday and today with no ill effects. We were going to take the oil pump cover off, drill the boss, and install a roll pin. But being that we didn't have an o-ring for the cover and it being stubborn and not wanting to come off easily; we decided to leave it alone. Does anyone know if this is going to cause problems in the long run, as long as the nut holding those tensioners on stays tight? The spring on the forward arm of the tensioner still applies pressure, just not in the optimal vector due to that pivot missing. Thanks.

 

I think you're OK. Tensioning system only functions until you tighten the nut.

This might be a problem, if you ever release the tensioner locking nut and lose your belt tension. Belt is tightened by tensioner taking up slack in belt when crankshaft sprocket pulls against valve train sprocket. If there's no leverage for spring to act on, it might not tighten belt adequately. You might be able to tighten by removing upper TB cover, pulling slack out of vertical TB span, and then tightening the lock nut. This assumes the tensioner arrangement will move to push against belt when you tighten.

You may want to discuss w/ Honda shop mechanic and understand whether this arrangement is "normal". There is no mention of the pivot stud in any of the shop manuals I've seen. I'm pretty sure the stud is there for models to 1997, but don't know about later models.
Perhaps Honda eliminated the pivot stud.

good luck

 

Texas,

Thanks for the quick reply. That's what I figured on. If we tensioned the belt by hand, and then tightened the nut, that it would be ok. Well, as long as it stays tight. I'm sure there is supposed to be a pivot there because I can plainly see that something did break off of there. I didn't see it in the manual either, but just from playing around with the tensioner, I can tell it is supposed to pivot about that point. I'll let her drive the car around for a week or so, and I'll take the TB cover off and re-check it. Hopefully it will still be properly tensioned.

 

Thanks for followup. I didn't realize there was evidence the stud was actually sheared away.

One possible scenariio of how the stud might have been sheared: If tensioner lock nut was left loose or became loose, the tensioner would be constantly moving. This would exert a bending stress on the stud, which might cause it to fail from fatigue.

good luck

 

What year models does this issue affect?

 

I'm not sure this is a common issue, but the 90-02 4-cylinder accords essentially have the same timing belt setup.