1998 Subaru Legacy 2.2

subaru
legacy

#1

Vehicle had died going down road. Timing belt broke. Replace timing belt and water pump - vehicle started right up after replacing - once warm - vehicle died - would not restart until cold again. Does it over and over. Compression is 0 at the warmed up - dieing time. As soon as the engine cools back down - vehicle starts and runs fine. Anyone ever had this happen?


#2

WHOA NOT GOOD…and I dont know what would do that other than …hmmm…Valves? I have been working on cars over 20yrs and never ran across this. Perhaps the engine was on its last legs…no…Im actually stumped I’m sorry.

The heat of the engine would expand the cylinders…and if the rings werent good they could leak but why or how didnt this happen before your head gasket issue.

You performed a compression test and your result was ZERO?! in all cylinders? Im having a hard time with this one…did you do a “wet” comp test as well?


#3

How many miles on the car? Is this the first timing belt replacement or the second?

When you say compression is zero, how are you measuring it and is it the same in all four cylinders?

What is the compression when the engine is cold?

I’ve never heard of anything like this before.


#4

The part about zero compression is very odd. The only thing I can think of that would cause this would be tight valve lash since it’s a mechanical lifter engine.

Has anyone been involved with valve lash adjustment during this engine work?

The odds of having valves this tight on all cylinders would be strange to put it mildly and could point to someone misadjusting them; as in running them down to zero lash.
Once heat starts building up in the valve train thermal expansion of the steel begins to hold the valves open a tiny bit. This could lead to zero compression and once cooled down the valve close again and you’re back to running well, albeit temporarily.

IF this is the case then you may have a problem if this has gone on for a bit. Tight exhaust valves can burn very quickly. Adjusting the lash properly may buy some time but any microscopic burning can lead to major performance problems, and a valve job.


#5

I think ok4450 is on the right track. I had a 71 VW bus that did this. By driving it flat out all the time the valves kept recessing into the heads. Finally I started adjusting the valves every time I changed the oil. By the way,flat out was about 72 mph- if you were tucked in behind a tractor-trailed.


#6

Yeah that would do it I guess…But I thought the Subie had no valve adjustment? I tried to look this up and only got further confused. On some 2.2’s there is NO valve adjustment…and on others there is…best I can do and if someone DID adjust the valve lash then OK45 certainly has a great point. However we still dont have the answer on the real compression numbers…NEED those…Is this Zero compression really happening?

If there is no lash I would also expect to hear some nasty sounds coming from the engine vale train as well…no mention of this either. Hmmm We need MORE INFO in order to help