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Blown wrist pin bearing need new heads?


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Well a coworker has a 2004 Subaru Baja.  He said the engine started to knock a crap ton, so he turned it off.  I pulled the motor last night and took off the heads, sure enouhg Piston #3's wrist pin is slapping around like crazy.  Popped off the oil pan found crap tons of Al filings, felt like 80 grit sandpaper.

 

Pulled off one head's cam, the bearing surface nearest the cam sproket looks shinny like all the cam's I've serviced, but as you go back they get more and more dull and scratched.  I'll see if I can post pictures.

Looking at the cam itself, same.  The rear most one looks very dull and ruff.

Should I tell him to find a complete engine?  If it were me I'd by the lower and buff out the cams, put it back together and watch it.  But this poor guy has NO car experiance nor tools.  Doing this as a favor for him.

Anyone?

 

DSCN0614_CC.jpg

Ones in the rear...

 

DSCN0615_CC.jpg

One near the cam...

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Doesn't look too bad to me. Plasti gauge it and see if clearance is within spec.

 

As for wrist pins, do you mean rod bearing? The big end where it meets the crankshaft is the common failure on the 2.5, and is typically a result of overheating.

As long as it didnt go through the block you can rebuild the shortblock fairly cheap. If you don't want to bother with a rebuild, just find a good long block and put it in the car with new timing parts. Might consider replacing the head gaskets if they look like they're seeping.

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Nope the upper connection to the piston.  Feels like the connection to the piston is very loose.  Lower connection is not the issue on this one.

 

He ordered a full engine today, should be here Wednsday the latest.  Going to put new head gaskets in that one and seals. 

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General Disorder - yep...  Full block on the way.

 

However, this morning I decided not to go skiing, dropped by and bought some plastigage - my old stuff was old.

I cleaned up the oil on the head and bolted the cam back into it.

Journal Clearance on the CAM. The spec is: STD: 0.055 - 0.090mm, Limit 0.100mm

I got: FRONT .075/.070, MIDDLE .085/.090, AFT .110/.115.

I figure if I hit them with scotch brite they may go more out of spec.

I'm going to talk to him, I can rebuild these heads and give them back to him.  Maybe he can get some $$$.

 

When I saw this I told him if it were my engine, I'd slap them back on and watch them.  On one of the heads it looks like an intake valve seal was bad, that side had a lot of crap on the valves.  Its a story of two halves.  One side looks okay, the other rather junked up.

He also had some leaky spark plug valve cover seals.  They were pretty much full of oil.

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