Another tapping noise thread

[simpreza2]

I know all about the tapping noise from other threads but I have a specific question...

 

Everyonce in a while the tapping will go away for a random amount of time, anywhere from 10 seconds to and hour or two. But it only goes away for a day or two, then taps constantly for a week or two befor going silent again. Does this sugest any particular item that I need to check/replace 1st or should I just go down the regular list?

 

and the engine has 200k.

[torxxx]

Oil pump reseal and HLA replacement. That is exactly what my engine does. I resealed my pump and it DID NOT fix the problem. HLAs are getting changed next.

[idosubaru]

HLA tapping generally is random and comes and goes as it pleases. as it gets worse, it will be constant. but normally temperature, oil level, driving conditions, etc can make it come and go at will, so i wouldn't guess you have any particular issue that can be addressed any differently than under the umbrella of "HLA tapping".

 

here is how i would start (i always have XT6's). your HLA's could easily be dirty and not frozen beyond repair. what i would do in my XT6 and have done multiple times, but i don't recommend this unless you're very confident in what you're doing. i would drain 2 quarts of oil and add 2 quarts of ATF (do less if you have small oil capacity to start with - XT6 uses 5 quarts). i feel perfectly comfortable driving it like this for a week. get it up to operating temperature at least, since the ATF detergents will work better when warm. ATF has a high amount of detergents and can definitely free dirty, stuck lifters. if you don't like what i'm saying, try 1 quart of ATF or a bottle of marvel mystery oil. i've had much better luck with ATF, but know others that have had good results with MMO. i'd say drive for 100 miles like this - but you can drive driving it once around town for 15 miles if you're not comfortable doing it. if it works, great. if not, you can always try it again. if this is your first time doing this, that might be a good idea to ease into this. in general i never add stuff to oil and don't recommend any additives. but i'm confident in this technique for cleaning up the lifters. and it beats pulling the timing belts and cams to get to the HLA's. 9 of my 12 HLA's just turned 200,000 miles yesterday and i don't expect them to tap anytime soon.

 

now - the oil seal. it's probably a good idea to seal your oil pump as well. first thing to do is crawl under the car and thoroughly inspect around the oil pump. really bad seals will show as leakage around the pump. unfortuantely on the XT's and XT6's (and probably most soobs) the crank seal is above the oil pump so it if it leaks it could also get the oil pump very oily. but - in general look for oil around the oil pump to indicate a bad seal. this doesn't tell you too much because a bad seal can cause HLA tapping even without noticing a leak. but if you see something obvious, it's nice to know for sure you need to address that.

 

if you reseal your oil pump be sure to have some gasket sealant ready. when you replace the oil pump to block seal you'll need a small dab of gasket sealant at 6 oclock and 12 oclock where the two halves of the block come together. don't forget this. the two halves of the block mate together behind the oil pump. you'll see a very faint zig-zag pattern where they mesh. a dab of sealant on that zig-zag mating point is required. i know XT6's really good and other soobs not very good, so if something seems out of place that's probably why.

 

good luck and have fun,

[idosubaru]

forgot to mention - if you do need to address the HLA's directly. post again later - don't necessarily have to replace them. they can be fixed outside the car. you can soak them, disassemble them and clean them up yourself or have someone else rebuild them. i wouldn't drop the mad loot for new ones, they are quite reliable with frequent oil changes and maintenance.

[simpreza2]

The engine has been tapping almos constantly for almost 2 years now, it was my dads car and he got sick and it wasnt a major priority, now that I have some time I want to fix it before I leave for Wyotech, so my brother can drive it. Ill try the ATF tomarrow when I do the oil change. And its worthless to look under the engine for oil b/c the whole thing is covered in oil. I plan on doing all the seals, belts and ect... soon.

Thanks

Jon