| Author | Message | ||
     Dave |
I'm using a Cometic EST top end kit to assemble my S3 but it didn't come with the 4 O-Rings (Buell p/n 26432-76A) for the cylinder stud insert (dowel). Does the Cometic EST head gasket satisfy this?  DAve | ||
| V2win |
DAve, Yes. Also, I found the Cometic rubber gaskets for the valve covers to be very hard to install. They were just a tad too small and would "crawl" back out of the groove of the valve cover spacers before I could get them tightened up. I ended up using OEM pieces there.All of the other Cometic gaskets worked very well. | ||
| Aaron |
DO NOT use viton o-rings with those head gaskets! You'll create a guaranteed leak. Yes, as good as Cometic EST gaskets are, they just haven't quite figured out how to make rocker box rubbers that fit. | ||
| Dave |
Thanks JOhn and Aaron for the confirmation. In the past...I've used the freezer to shrink rubber seals a tad or the oven to expand them a bit. When I had my initial rocker box keaks years back, the OEM rocker seals were too large going back on. 30 mins or so in the freezer had 'em fitting perfect. ANy special note or trick for getting the piston pins back in? DAve | ||
| Aaron |
I think you'll find the Cometic rubbers, right out of the box, to be a touch small. I stretch'em out a bit. On the flip side, after they've been used, they fit better. There's a tool for r&ring wrist pins, I highly recommend it. Generally they'll slide right in a new piston, they only get sticky with use. | ||
| Dave |
I made a puller for the pins so I expect I'll use a variation of it to get them back in. I didn't know if there was any special trick you or anyone else has found. Thks. DAve | ||
| Dave |
To answer my own question with getting the wrist pins back in.... I attempted to press 'em in on the bench with my home made tool but that was a no-go. Worse case scenario is that I dorked up the piston and it'll all self destruct in short time and force me to do it again using Hurricane pistons or similar.  Failing that, I oiled it again and tapped it in with a 2x4 on the bench to get it started. Then lined everything up on the rod and tapped it in on the engine as well. They went in very easy this way. DAve | ||
| Dave |
Another question or two about the Cometic EST kit. What are the four blue/brass pieces for? They have threads on one end. And...the copper washers are rocker cover washers taking the place of the fiber OEM ones?  DAve | ||
| Sportyeric |
Those blue things be valve stem seals. And if you were tapping the pins back in, I hope you made some effort not to bend the con-rods. I have heard that that is a danger. I seem to remember that heating the pistons in the oven should expand the pin hole. No? | ||
| Firemanjim |
Damn,if you can bend those rods tapping on them we are IN trouble!!! | ||
| Sportyeric |
I made that comment for the benefit of future readers. It had just been mentioned on the XL-List as a possible cause of a detonated engine. A riding bud with constant engine woes has also been worried about the same thing. I think over-revving was the source of both people's troubles. Nevertheless, I don't think con-rods are designed to withstand sideways force delivered with a hammer. I made the comment based on cautions I've read, rather than reports of anyone finding such damage. It seemed reckless to leave "hit-em-with-a-two by four" as an unqualified recomendation. Anyone know how hard you can hit them and how bent can they get without damage? | ||
| Dave |
Understand your intent Eric. If you were quoting me, you misquote me.... I said "tapped it in with a 2x4". I think future readers should understand what it takes to get the top end back together too. Using a hand press to get the pin in the piston while still in the cylinder wasn't working. Tapping it in with a piece of wood did work very well. Almost too easy. Once in the piston, I placed the cylinder on the rod and tapped it in all the way. Quite easy actually. There wasn't allot of sideways pressure on the rod because he piston is in place. No striking blows... no hammer or sledge. DAve | ||
| Sportyeric |
No slagging intended, Dave. When I last had mine apart, everything just slid easily. The benefit of a worn out engine! When my buddy was disassembling, and, I think, re-assembling his, it was as if the wrist pin clips were still in. He got it apart with a jury-rigged puller, as you've done, and it put up such a fight that we considered the old piston as likely unusable. (He was replacing it anyway but I sometimes use his cast-offs.)I recall the install took what we later thought might have been excessive persuasion. |
