valve/spring question

[DreKat]

tonight i droped the engine and removed the head in surch of the reason for a strange sound coming from the engine. i found the problem right away one of the valva springs is compressed, all the other are working fine. how do i un compress the spring for my 98 Kat 750? and what else should i look for?

[The CyberPoet]

Re: valve/spring question

how do i un compress the spring for my 98 Kat 750? and what else should i look for?

If the spring doesn't have anything holding it down (such as the cam lobe follower), but is still compressed, replace it. There is no reliable way to "decompress" a spring which has compressed past it's structural point of return, and that's what I think you are saying... in other words, you can pull or compress springs a certain distance without damaging them, and they'll snap back to their original size; if you pull or compress them past a certain distance, they deform and will never get back to their original size. It might also be a case of the spring having lost some of it's length (snapping away)...

As for what else to look for:
(A) Why did this spring stick in the compressed position -- i.e. is there something loose in the top of the engine that got between the spring and the cam (such as a broken piece of tappet or another fairly large piece of metal)? Does the valve have all it's parts (nut adjuster, etc)?

(B) Is that valve stem still straight, or has it bent? Is the valve itself ok, or has the face of the valve burnt or worn down (are the edges still camphered?). You may want to contact Suzuki America if you suspect it may be a manufacturing defect -- they need to know and may offer you a replacement spring/valve for free.

(C) If you grab the cam, is there any play, indicating either bad cam bearings or slop in the cam chain... How much play is there in the cam chain?

(D) Is the tappet still healthy?

What happens when you turn the engine by hand (either by putting the bike in gear and rotating the rear tire, or using a wrench on the timing signal generator)?

Seems like if you stick around here long enough, you'll hear of everything under the sun... I swear...

PICTURES PLEASE!

Cheers
=-= The CyberPoet