95 4Runner SR5 V6 185k miles. OK, I just finished up with rebuilding the top end last week and I've been driving it around for the last 200 miles or so. I notice a tapping sound that is not crazy loud, but it's there. It sounds like a sound that was there before I had the heads reworked. A machine shop would correct any valves while it was being serviced correct???? Could it be possible that they didn't do a good job? The #6 cylinder was at 40 psi before I took it all apart, and this seems to NOT be the side where the sound is coming from now. Is it possibly the pair reed valve? Supporting this would be that I don't hear the sound starting it cold? ...and only after driving it for 5-10 minutes? Also, I put a stethiscope on it, and it was louder on the reed valve, but it's really hard to say with that intake in the way? ...and the reed valve is the same as before (tapping sound was present on that side before as well) I REALLY don't want to have to take the heads off again. I'm sure many of you are shaking your heads right now!!! Please help. Any suggestions? How do I check the reed valve to be sure? Thanks, Brian

 

I have had a "clicking" sound with my '94 3vze for the past 110,000 miles & I gave up trying to figure it out. Either the reed valve or a noisy injector. I cleaned out the intake & plenum, installed new plugs/wires/distributor cap/rotor, PCV Valve & grommet, and completely removed & cleaned all the injectors, re-installed with new o-rings/seals. It now runs GREAT and I refuse to worry about it anymore!

 

its probably an injector honestly....pop off the drivers side valve cover and check your shim to cam clearances just to be sure...

 

I had the injectors re-conditioned, so they're like new. I don't think I can live with that noise though. I'm going to sell this, and I know a future buyer will question it. If a lifter needed a shim or two, wouldn't the tapping sound be heard right when starting it up?

 

it sounds to me like an incorrect valve clearance. When your engine is cold, the valve lash is going to be at its greatest, as the engine warms up, then the clearance goes down. So if you have a valve set too loose or too tight then that could cause a tapping noise. Also in an extreme case you could have an incorrect head gasket, with too small of a bore which would cause the pistons to slap against it at TDC, its kinda extreme but ÅÅÅÅ happens. Good luck!

 

That's what I didn't want to hear, but it sounds painfully right. This is something that the machine shop I took it to, should've corrected right? Isn't this a standard practice when having the heads reconditioned? Should I try to take it back to them and complain? Man, I just want to see this thing! Thanks, Brian

 

Yes of course you should take it back to them and complain...valve clearnaces are set by the thickness of the shim in the bucket and honestly is easy as pie to set correctly. If they didnt do it properly, its something that you can definately do on your own.

 

So, I shouldn't be driving it around until this get's taken care of? It couldn't possibly be the reed valve? When you say easy as pie, does that mean I don't have to take off the cams? Ugh!

 

The cams arent that bad honestly, but no you dont have to pull the cams, what you will need is a toyota fsm, feeler gauges, a shim puller (vw or toyota) and something to hold the bucket down away from the cam while you pull the shim using the puller. Driving it around shouldn't be an issue, but im not sure...

 

If I took this thing to the dealership, would they be able to check it out and tell me without a shadow of a doubt that a valve did or didn't need adjustment? Would they put it on a computer? Do you know how much they might charge me to do this? (I've done the whole top end, and don't really care to take it even partly apart again.) Thanks,Brian

 

computer isnt going to tell you anything.

the dealer will say they have to tare it down to run the valves.

stealership is going to be expensive regardless.

 

So what you're saying is that there is no way to know for sure, unless you take some stuff apart and investigate? Brian