Blew the LH head gasket after exhaust valve adjustment

[Earl43P]

Been driving it for 30+ miles.
Knew the the Aft LH exhaust valve was rapping, heard it clearly with a mechanic's stethiscope.
That side's exhaust was clearly richer, based on the wet soot.

Rode it home at 4-ish.
It was thoroughly cooled by 8, so I pulled the valve cover and followed the tutorial on valve adjustment.

Found it was over .007 and tweaked it to .005.
Did a check on the other cylinder, found both were spot on (confirming the nice swish sound on the stethiscope), made no adjustment on it. Didn't touch the other side. Rechecked the clearance on the LH aft exhaust valve, still perfect. Installed the valve cover, started the engine.

No more tap. Revved it to about 1500, sounded like butter. Perfect.
Revved it again, to 2 ground or so, it made a raspy ugly sound, and I see a spray on the garage door.
Immediately shut it down, quicker than a cat can lick its rearend.

Coolant is coming out of the exhaust joint.



Brand new HG's. Can't imagine why an exhaust valve (was loose, I adjusted it properly) adjustment would cause the head gasket to blow, but here I am!

[Whiskerfish]

Wild guess but if the head gasket had been leaking at all it would act as a cleaner removing any built up carbon on the valve seats and that would effect the valve lash.

[Oldewing]

Wild, maybe but real good idea, I could see that happening quite easy.

[gregforesi]

I have to believe this is just a coincidence and there was already a problem with the head gasket. The valve lash generally gets tighter as the seats get pounded into the aluminum head.
Out of curiosity were they Honda head gaskets?

[MikeO]

Maybe cam belt timing off piston hit valve this would explain extra clearance did you torque head 43-45 ft lb the torque was increased from Honda because of head gasket failure this was a memo out by Honda

[robin1731]

Maybe cam belt timing off piston hit valve this would explain extra clearance did you torque head 43-45 ft lb the torque was increased from Honda because of head gasket failure this was a memo out by Honda

Maybe a little of this. Also coincedence I think.

I will add though. Four hours isn't enough time to let the engine cool enough to do the valve lash. It really needs to set over night, 8 hours or more. The head will feel cool but the internals are still warm and it will make a difference.

You might think about getting the heads surfaced too. It may not have been flat.

[Earl43P]

Appreciate all the comments and insight.

Will know more when I get it disassembled.

I did torque them to 45, but never did a re-torque.

[MikeO]

if you had the heads off you should know if you put the restrictors in it has 2 small o-rings on it. did it have low oil pressure before you took it a part?

[MikeO]

sorry wrong thread

[Earl43P]

Had to be burning coolant in this cylinder (scrubbed so clean).

It is NOT the cylinder that I adjusted the exhaust valve on. It's the dirty one next to it.

[Earl43P]

Appears to be fatal for this engine.
You may not be able to make out the gouges on the cylinder liner and wall, but the valve did that.

I suspect the head gasket (new) was letting coolant in that cylinder and heat did a number on the intake valve.
I didn't measure the torque to loosen the head bolts, but the two in the center were clearly looser than the outers.

Guess I should have re-torqued those head bolts after a couple engine runs (heat cycles).

I'll do a bunch of reading/research before I ask a slew of questions, but I have a line on a GL1000 engine.
Or someone could tell me now, "won't work", "easy swap", "too hard", etc.
Mine's an 82 GL1100, I'll talk to the guy tomorrow and find out what year the 1000 engine might be from.

[bladredhead]

ouccccccch. 1000 into an 1100 should be pretty easy, as the opposite has been done. the gurus will be along shortly to confirm

[CYBORG]

eather engine will go in, but if you have to replace it why not go with an 1100?

[Earl43P]

either engine will go in, but if you have to replace it why not go with an 1100?

Because I know where there IS a 1000 engine, and I know the guy selling it. Just have to work a deal and assess its condition. His Dad kept it as a spare.

I'm all ears if you know where there is an 1100 engine close to me and the 1000 engine falls through (I'm hoping his price is fair).

[wilf]

So the timming belt was off is that what caused this? The ticking sound before you tightened the lash was the valve just hitting the piston and after you tightened it up Well you know what happed then
Wilf