My '96 GSR has a weird valve tap issue. First of all, I put in a Type R crank about 4k ago, with new bearings, etc. I started it up, and once we got the throttle adjusted, it ran like a sewing machine..beautiful. Took it around the block a couple times, and then drove in the garage. I turned on the AC to make sure it still worked, and all of a sudden I start getting loud valve knock. I didn't think anything of it at the time, so I turned it off, and called it a day. Next day I turn it on, and the valve knock is still there. The noise goes away when I give it some gas, and comes back as the revs come down/gas is depressed. The noise also goes away completely after the engine warms up. After about 400 miles of this, I bring it to Honda to have them adjust the valves, and they do...the engine's is much quieter in a sense, however it still has the really loud valve tap, and same gas/noise characteristics. The noise is definitely coming from the head as well. Does anybody have some ideas? A seal or something? I'm stumped.

 

Morning bump

 

Must be a good question, haha

I'm going to take the valve cover off to take a look to see if I see anything evident. Is there anything I can do while the valve cover's off to narrow it down?

 

Is it more of a tick or a knock? Recheck the valve lash and check your lost motion assemblies when you have the valve cover off. Mash them down and if they have a sluggish return then they could be bad. There is a thread in the all motor forum talking about the LMAs that you should check out. Hopefully this helps a little and you will be able to find your problem.

 

It's a valve knock, I should try and get a recording of it, would help more. I'm sure it's not a rod bearing, since I just replaced them all maybe 4k miles ago, along w/ rod bolts, so I know they're not loose either. I'm not sure I understand what you mean by mash down on the loss motion assembly, I'll check out that thread.

Edit: Just push down on the LMA's w/ my hand?

 

The lma is like a little shock. It sits under the vtec rocker (center one). It has a hole that goes through it and you can push on it with a punch. Its pretty ez to test when you take your valve cover off. Just push down on it to compress it and it should bounce back readily fast. If it fails to do so or is sluggish as slaminsam stated it may not be taking up the gap quick enough and the back of the rocker is slamming into the lma causing your knock.

 

Yeah, I gotcha now. I researched it quite a bit last night, and found out that's probably my problem. I really don't think it's the valves at all. Another project added to the list. Might as well do timing belt/water pump/tensioner all at the same time, lol

 

hmm my brother's Accord is making a ticking noise, as well, even after several valve adjustments. Lucky for him there are only 4 LMA's on his car and they're only $8 each.

damn GS-R's have 8 of them at $25 each