Background story: So, my engine started making a noise a while back. It was just a bit of a tick/flutter just above idle. I didn't think much about it... I assumed it was slightly misadjusted valves and figured I'd get to it as soon as I had a chance. Then, right after my 4th run at my last autocross, it sounded horrendous. Really loud tick/flutter sound throughout the entire rev-range. I figured, "Damn, there goes the second set of Toda camshafts". So, I let the car cool off and pulled the valve cover. Camshafts looked mint. So, I checked the valve clearances. Dead on. So, I was bumfuzzled. I buttoned it back up, and started the engine and the sound was gone, except for the slight tick/flutter just above idle. Weird.

Current diagnosis: I took the car out and ran it a bit tonight and the sound came back (I hadn't driven it since the event). I pulled it into the garage and started doing the "screwdriver test" to pinpoint exactly where the noise was coming from. I already knew it was coming from somewhere around the front of the engine so I started there. Cylinder head? Nope. Block? Nope. Intake manifold? Nope. VTEC solenoid? Getting warmer. That little doo-hickey below the VTEC solenoid? Bingo!!! I didn't actually know what that was, so I looked it up in the Helms manual, and it turns out that it's the cam chain autotensioner.

Question 1: I looked at the Helm's exploded view of the autotensioner, and it looks like a relatively simple device. My question is: What part of this autotensioner could be making the sound that I hear? It really is like a tick or flutter, almost like a baseball card in a bicycle spoke.

Question 2: Going by the sound described above, will it be sufficient to replace just the tensioner, or should I expect to replace the tensioner arm, also. Looking at the manual, it's a relatively small job to replace the autotensioner, but much more labor intensive to get at the tensioner arm.

Question 3: What damage could be done by continuing to drive with a bad autotensioner? (i.e., how imperative is it that I repair this immediately?)

BTW... you can see this thread, if you're wondering what part I'm talking about:
https://www.s2ki.com/forums/index.php?showt...dpost&p=4025806

As always, any information will be appreciated!

 

[QUOTE]I pulled it into the garage and started doing the "screwdriver test" to pinpoint exactly where the noise was coming from.

 

marcucci-

Thanks for the reply. In your response to my 1st question, you said that the autotensioner is not making the noise, but it is communicating it. How so? Would it be due to the tensioner allowing slack in the chain and kinda "bouncing" off the tensioner arm as the links in the chain go by?

I'm going to order a new autotensioner, and I'll let you guys know the results once it gets installed. Considering the fact that the possible worst case scenario sounds pretty bad, I think I'll park the car until I can get this resolved.

BTW... to answer your other questions, I'm currently running Mobil1 10W30 and still using that filter that you installed the last time you had the car (I've only put about 1500 miles on it since then). I haven't noticed any leaks around the tensioner body.

Considering the types of issues that I've had, I'm seriously considering installing an oil pressure gauge. How difficult is that? What permanent modifications are required, if any?

 

[QUOTE]In your response to my 1st question, you said that the autotensioner is not making the noise, but it is communicating it.

 

Edit: that's 1/8 BSP/NPT not 1/4 (1/4 is huge).

 

Just wanted to follow-up with this thread... I installed the new autotensioner today and it appears to have resolved my problem. The engine is now as smooth as silk.

The install was relatively easy. I had a bit of trouble w/ step 25 (diagram above) where you're supposed to compress the tensioner with a bolt and lock it into place with a nut... but I eventually got it. The new tensioner assembly came pre-assembled with the "locking-pin" already in place. Just insert the new tensioner, snug up two bolts, "pull the pin" through the maintenance hole, and re-insert the maintenance hole plug.

So, it seems the car is happy & healthy again. Now I just have to keep it that way.

 

kinda OT but I can relate to what marcucci says about the h22a and its auto-tensioner. Mine went out and the belt made a GRRRR sound on deceleration (belt and tensioner was kind of a pain in the you know what to replace. Some prefer to switch over to the manual h23 tensioner, not as plug and play but is more safe and reliable) But I think it would be sort of the same situation, where the chain would be making the sound if it was flapping around.