Warped valve cover

[Larry D]

I found a replacement engine for my '81 GS750L. Thanks Mike !!

I've swapped a few parts here and there. The biggest of which was the valve cover. The replacement engine's valve cover is extremely warped.

I think what happened is the PO tried tightening it down without it being properly seated on the alignment dowels. The engine was absoltuely covered in oil, presumingly from the cover being boogered up.

The question is.....Is it possible to get the thing flat again and salvage it ? I'd hate to throw out an otherwise perfectly good valve cover.....

BTW...I'd like to say a huge Thank You to bwringer who stopped by last night to help me swap the engines (them babies aren't light) and drill out a broken exhaust bolt. I should be starting it up Sat or Sun. This will be the second time I brought this thing back to life.......and hopefully the last.

[Nessism]

Can you use the cover off the trashed engine?

[Larry D]

Yes, I swapped the valve covers so, no issue there. I just hate to see a otherwise "good" part be rendered useless.......

[Guest]

The question is.....Is it possible to get the thing flat again and salvage it ? I'd hate to throw out an otherwise perfectly good valve cover......

I "coaxed" my valve cover back to flatness using a soft rubber mallet.

Find a reliable "flat" surface to use as your inspection tool & place the sealing surface on it to identify the places that are raised up.

Use a piece of plywood or such over a hard surface (like a concrete floor) and place a wooden shim under the area you want to lovingly whack back to flat. I used a strip of soft wood about 1" W x 1/2" thick & kneeled on the end opposite to where I was whacking. Keep checking the cover for flatness between whacks.

Took a little while to get "almost perfect" but that soft aluminum cover moved enough to get it flat again - worked for me!

Good luck,

Mike

[Larry D]

That sounds okay. I love using big hammers !!!

This thing is really out of whack....no pun intended....I'm guessing 3/8th-1/2 inch from corner to corner. I'm not sure smacking it will get it back, but it's worth a try, I suppose.

I was thinking of putting something heavy and flat on it and heating it in the oven at some undetermined temperture and letting the weight, heat and gravity form it flat again. Not sure if the oven could produce the temperture required to heat the aluminum enough.

[Dogma]

Any chance of duplicating whatever process warped that much in the first place? Anyhow, with that much warp, I think you'd have to heat it no matter what, to keep from cracking it.

[Guest]

That sounds okay. I love using big hammers !!!

This thing is really out of whack....no pun intended....I'm guessing 3/8th-1/2 inch from corner to corner. I'm not sure smacking it will get it back, but it's worth a try, I suppose.

I was thinking of putting something heavy and flat on it and heating it in the oven at some undetermined temperture and letting the weight, heat and gravity form it flat again. Not sure if the oven could produce the temperture required to heat the aluminum enough.

Well, I'm not sure of the actual aluminum alloy of the cover, but as an example:

AL 2024 alloy (my guess for this material) - solution temp is 495 F

Heat at 495 for at least an hour, then immediately quench in chilled water (the quench MUST be done very quickly after removing from the oven)

Straighten - the material will now be in T0 condition (very soft)

Age at 350 F for 6 - 8 hrs to bring it back to T6 condition (or similar)

Check straightness again, most likely distorted...

Buy new valve cover after ruining this one !!

I think the hammer whacking is the best option.

Mike

[Larry D]

I may give that a try.....nothing to lose. The thing is trash the way it is.

[mriddle]

Call me Saturday so I can hear it run


606 207 0325

[67fire]

Buy one used from a member of this forum? I have seen them go for $10.00.
Sounds like too much effort to save $10.00.
Is it just me or do you enjoy the challenge?

Eric

[Larry D]

Call me Saturday so I can hear it run


606 207 0325

Will do.

[Larry D]

Buy one used from a member of this forum? I have seen them go for $10.00.
Sounds like too much effort to save $10.00.
Is it just me or do you enjoy the challenge?

Eric

It's just you......

Just kidding. I don't need another one. I just like to experiment.

[almarconi]

Hey Larry..Glad you got another engine for your bike. Hopefully this one will last a long time. Make sure the oil pump works before firing it up.