Topic: valve spring free length question - F2

[bhkrause]

Hi, all.

Finally getting around to redoing the head on my 77 F.  I've got a redone K head with new Kibblewhite springs, figured I could move the springs from that one to the F, so I took one of the spring sets off and measured them.

The Honda service manual for the F2 sez free length for the inner should be 40.3mm, outer 43.05mm, with the service limits being 39.14mm and 41.74 respectively.  The outer spring is fine, measuring around 43mm, but the inner NEW spring doesn't even measure at 39mm.  All of the old inner springs from the F were also shorter than 39... 

So - was there a typo in the Honda service manual, or are all of the inner springs too short?  They seem to be very consistently sized, but why would there be that much of a difference between the spring length and the manual?

Will this cause a problem?  My other head died when one of the spring retainer collars split, and another was well on the way to splitting, don't want to go through that again..

thanks.
Bernie

[MRieck]

Bernie
 I measured 4, F2 inners @ 37.86 to 37.90 mm. These are low mileage springs too.

[MRieck]

...and the reatainers split because they are too thin in the keeper area. In general you have to over rev the engine a few times to do it .

[bhkrause]

Guilty as charged...

[wohali]

Resurrecting a very old thread...anyone else have measurements on free spring lengths? Mine are showing 43.5 and 39.5mm respectively...seems reasonable.

I can't find F2-specific tolerances listed anywhere in my Honda shop manual, just the stock length measurements of:

Outer: 41.2mm standard, 40.0mm serviceable limit
Inner: 38.1mm standard, 37.0mm serviceable limit

Where did you see F2 or F3 specific spring length values in the shop manual?

[Edit]: Found it. Wow, I didn't realize there was an F3-specific shop manual, I just had the bog standard one + the F3 supplement. This is far better!  For those following along, here's the values from it:

Outer: 43.05 standard, 41.73mm serviceable limit
Inner: 40.30 standard, 39.14mm serviceable limit

Guess mine are still ok Hope the new, harder valve guides will keep the inner springs happy.