My wife's Subie with 105K on it developed a radiator fluid leak and by the time she pulled over the temp gauge was redlined and steam was pouring out - head gasket leak. So we had head gaskets replaced, heads resurfaced, timing belt and idler set replaced, water pump replaced, valves checked (machine shop said they didn't need turning). It runs great EXCEPT there is now a prominant tappet type noise coming from the driver's side front cylinder area. Its there at all times, regardless of RPMs and engine temp. The mechanics I took it to are competant and good people and they went through the valves, shimmed and adjusted, checked camshaft, valve springs. We are all scratching our heads on this one. We didn't get into the engine except to visually check for cylinder cracks, and one idea is that this is a worn piston wrist pin. But, the noise was not present before the top end job. Any ideas ?????

Thanks.

John

So they reshimmed the lifters?

 

I'd use a stethoscope and try and pin point more where the noise is coming from.

Yep - lifters were re-shimmed.

Yep - lifters were re-shimmed.

Arn't they rockers on the newer subarus? well.. same thing i guess. I have that same ticking noise, gets worse as it gets cold... i've heard of people fixing it w/ seaform or something like that.. but i'm scared of taking apart my motor

i t6hink he has the solid lifters that the clearance is set by miking the shims and go from there,my guess would be that the clearance is to loose on one lifter.

This motor has solid lifters and the shims were set and re-checked over and over to try to get rid of the noise. It is something other than lifter adjustment ......Thanks for the comments so far, I'm still searching for the cause. I guess it could be something to do with the connecting rod (wrist pin?) even though the sound didn't exist before the head gasket job. The engine leaked coolant and maybe this put stress on the pistons as coolant entered the combustion chamber. Any and all ideas are appreciated.

 

John

I bet its the famous piston slap. When you dump coolant in you wash the walls and accellerate wear. Does it do it worse when cold? If it is piston slap it will tick on for years.

is this a tic-tic or more of a light knock?

What condition is the timing belt tensioner in ??

good point Setright, I remember folks complaining about knocking timing belt tensions a while ago.

Thanks again for all the replies - the timing belt tensioner/bearings were also replaced. Its more of a tick tick than a knock. If anything, it gets slightly louder after warmup, or at least the same as when cold. When I put my ear next to the engine it sounds exactly like a valve tappet click right above the valve cover on the front driver's side. I'm hoping it is the famous cylinder slap as from what I've read the engine will run a long time with this condition.

 

 

John

piston slap dont sound like a lifter,im betting the rocker assembly could possibly be pluged at that lifter not letting the tappet get enough oil,if the lifter has been checked for clearnce this is about the only thing that will make it tic.

One thing that can do that is a slightly worn cam that gets mated witha slightly worn follower. The adjustment can be fine at the top but wear on the ramp can make a tick and it will look OK.I had a tick on my Mercedes that made me near nuts until I pulled the cam and had it on the bench where I could see the worn spot.

Since this is a 98 Forester it should have shim adjustment.

This does have a shim adjustment on the lifters, and the shims were checked, added as needed and rechecked. The worn cam sounds like its worth looking into, except the noise didn't exist before the head gasket job, and I'm not sure the leaking gasket/overheating would have made this worse. As far as the plugged rocker assembly being a possible cause - doesn't this apply to hydraulic lifters only? This engine has solid mechanical lifters. Thanks again for the ideas - I'm gathering all the info I can and before taking the engine apart again.

 

 

John

Thant should be hydraulic only and the cams should make noise only if you switched followers.

 

You did disconnect injsetor or short plugs to narrow it down did you not? I have heard some injectors make a clicking sound too.

The mechanics who did the head gasket install pinpointed the noise to the driver's side front cylinder. I don't know if they checked the injector, but I will see if I can disconnect it or use a stethescope to determine if it is a noisy injector - that would sure be good knews, as I fear it is an internal engine noise. Thanks

 

 

John