I recently rebuilt the bottom end of my H22 due to bad piston rings. Car is running great except now whenever I first start it I get a kinda loud tapping noise from the head (nothing was wrong with the head before the rebuild). The noise goes away once I drive it around for about 20 mins and another thing I noticed is that it also goes away if I rev over 2700 rpm when I first start it...wierd. Lost Motion thingys you guys think lol??

 

lost motions are easy to diagnose. you just push down on them and if they don't spring back up right away they're bad. sounds more like you need a valve lash adjustment though. or some kind of exhaust leak that seals itself up.

 

I forgot to mention all the valves have been checked and adjusted within spec but it still makes the noise...

 

might be fuel injector, but just a guess

 

I don't think a fuel injector will stop making the pulsing noise once the car warms up lol - if it did you would be stuck on the side of the road!

I'm beginning to wonder if its the lost motion assembly...

 

Buddy.... try this out... during cold start... just start the vehile without pressing the accelerator and go towards the engine bay and open the oil cap and see if oil pressure is there or not. The upper part should be submerged with oil.... my car's oil pump was not sending enough oil during idle till the oil got hot enough.

As you press the accelerator, the pump gets revolving at high rpm and sends enough oil which removes any sound from the engine. And once the engine gets hot (running temperature) it smooths out everything.

 

so if this is the case then you need to check if your oil pump in the lower chamber is installed properly and is working ok or not.

 

friendayaz, I did what you said and I could see some oil being splashed around inside the oil cap opening on the valve cover - it was not ALOT of oil splashing about but I could see some - is that normal?

I also thought I would mention that I do have a oil pressure gauge installed and it registers about 50 psi when I first start the car and then once its idling and warmed up it drops to about 15 psi. When I am driving, it mostly sits at 50 psi but if I rev up to about 4000rpm or more it goes up to 75 to 80 psi. Remember this is a h22a motor so is that normal?

 

Can anyone else comment on my message above ^ - is everything ok?

 

Could be coming from the bottom block. Did u reuse your pistons?? if so did u get them measure to make sure piston to wall clearance are in spec?? i might be piston slap. Does it on start up but once it warms up the pistons expands a little causing the noise to go away. Also once u rev higher the noise might be too fast that it gets drawn out by other engine noise.

 

I'm thinking it has something to do with the bottom block since the head was fine before and everything up top is within spec and adjusted correctly.

 

Hey I did put in forged pistons and I just found out that sometimes with forged this is normal and to just let it warm up. Yea its dead silent when its warmed up btw...