June 14, 20169 yr So recently I picked up a nice 86 XT GL-10 that is nearly perfect but is leaking oil everywhere. I decided to do a shortblock out reseal. When tearing down the lh head I noticed the cylinder 4 exhaust valve is bent towards the top of the stem. It also looks like a few guides have dropped slightly. I was just wondering how common this is. In all the Subarus I've rebuilt I've never seen a valve bend at this spot. Also, amazingly, the rh head has no cracks between the valves. The lh head looks like a normal ea82 head.
June 14, 20169 yr Never in 20 years seen a bent valve on an EA81 or 82. Never even heard of it unless someone dropped something down the intake.
June 14, 20169 yr I have heard of just one EA82T with a contact between valve and piston causing some bend after a timing belt slip or break. Yours makes the second out of three forums. Can you post up a pic of the removed valve? I have had one head in need of a new valve guide as the valve stem had worn enough tp allow a3mm ? sideways movement in the head and cause a mystery performance problem. Fixed with a K-line insert and in my current EA82Mongrel. I am wondering if you guide is nice and round inside to allow its angle and interference change, or just the guide slipped in to allow this - me thinks.
June 15, 20169 yr Author Its really hard to tell by looking at it that it is bent. It does have a shiny spot where it was rubbing. It was difficult to remove from the head and when I spun it in a lathe it was pretty obvious where the bend was. I'll try to get a pic in the next few days.
June 15, 20169 yr I don't mean to start a tiff here, but based on deck height, piston height, TDC height and valve protrusion, it is impossible for the valve to contact the piston on an EA82 engine. Just for s&g, I took a bore scope to my XT when I rebuilt it and the clearance with the valve open and piston at TDC is huge in terms of interference specs. The only way I could see it happening is if the block or heads were shaved and the rod stretched. Any valve that is bent by piston contact is going to leave a mark on both especially if the pistons do not have valve reliefs cut/cast into them.
June 18, 20169 yr I was thinking the same thing. any signs or knowledge of prior engine work? Sounds like maybe this thing wasnt maintained well or driven hard? Heads shaved a ton? Lol
June 18, 20169 yr A bent valve is possible with some water ingestion at low engine speeds. Edited June 18, 20169 yr by Uberoo
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