rootingfortrees

Hello everyone. Recently I changed the timing belt and water pump on a 2001 Civic, and after hearing a noise coming from the belt cover area (after a few days of driving), I discovered that the tensioner for the timing belt was sitting at an angle to the engine block, allowing the timing belt to rub against the lower cover. I pulled off the tensioner and discovered that the threads on the bolt were somewhat chewed up (not stripped, but ground down a bit at certain points), so I replaced the bolt and reassembled everything. The engine didn't make any unusual noises when I turned it on, so I though the problem was resolved. I turned it on today and discovered that the tensioner slipped again, and now the timing belt is actually touching the crank pulley.

I have no idea how the pulley is able to twist around at all on the bolt, especially since it didn't feel like the threads on the bolt were stripped when I was removing or installing it. Could this be caused just by not having the bolt tightened down sufficiently (i.e. is it possible there's enough space on the bolt for the tensioner to twist like this)? When replacing the timing belt initially, I followed the instructions in a repair manual (I can't remember which it was and don't have it available now), and the directions regarding installing the tensioner were fairly vague. I didn't find the DIY thread here until after this had happened, and the guide that I did find online didn't really go into detail about the tensioner either, so I figured it wasn't that big of a deal. Not knowing any better, I (stupidly) installed the tensioner by first connecting the spring and then bolting it into position.

I'm worried that I may have damaged the threads inside the engine block itself, since replacing the bolt didn't resolve the issue, and I had to apply force to the tensioner in order to create enough slack in the belt to get it around all of the pulleys. However, the threads didn't feel stripped at all while I was installing the tensioner, and I can't really see into the hole to check since it's so far down the side of the engine.

I've attached a couple of pictures I took of the tensioner sitting at an angle (sorry about the poor quality; it was a cellphone camera at night). These pictures are from before I reinstalled the tensioner, since I haven't taken the lower cover off yet since discovering it slipped again, but it appears to be sitting at a similar angle now. What I'm wondering specifically is whether it's possible that I damaged the threads in the engine block in a way that allows the bolt to thread in properly but also allows it to move enough for this to happen; however, any other related advice would be greatly appreciated as well. In the event that I did damage the threads in the engine block, is a Heli-Coil my best option?

I'm probably going to take the engine apart again tonight to take a look at this, so I should be able to provide any additional information necessary.

Biscuit

I have not yet made this repair on my 2001 CIvic but I have done it a few times on other Hondas/Acuras.
From what I see in the FSM it appears that as usual in a Honda with a located tensioner there is a locating stud that the tensioner must engage. If the tensioner is not clocked to accept the locating stud the tensioner WILL sit at an angle like you pictured.

Nathan