Am I supposed to pull straight up on them? Use the wing as a king of rocker lever? Twist/spin the butterfly wing (just tried that and all it dose is spin on the post)? I consulted my engine manual, and while it has plenty of pictures and drawings of butterlfy petcocks, it never says how to operate them.
Thanks--JS
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Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California
From my memory, there's only two petcocks on the engine. One to drain the heat exchanger and one that is near the thermostat. The wings on these petcocks rotate counterclockwise to open (drain). Usually about 5 turns or so to full open/close. Either full open or full close, they bottom out and stop turning.
Nick Caballero
Retired C36/375IA Mk II Technical Editor
Joel, are you referring to something like the attached photo? If so, you unscrew it to open and tighten it to close it.
If you have this and it is just spinning, maybe the handle has become disengaged from the shaft and you will have to replace the valve.
Duane Ising - Past Commodore (2011-2012)
s/v Diva Di
1999 Catalina 36 Hull #1777
Std rig; wing keel, M35B, Delta (45#)
Punta Gorda, FL
http://www.sailblogs.com/member/diva-di/
Thanks guys. Is there a way to reattach the butterfly wing to the post if it is spinning freely? I just checked prices and new valves cost like fifty bucks each. Also, for some reason my M35AC doesn't have a petcock underneath the main heat exchanger at the back of the engine. The reason I know this is because I just went looking for it as a way to drain my antifreeze before removing my exhaust flange It sure would have made things nice and easy if I could have drained my antifreeze there unstead of at the dang water heater! I also tried to loosen a bolt in the block that the manual appeared to indicate was the antifreeze drain. Boy was I shocked when oil came out of it! Back to the drawing board for me...
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California
PS yes dissing, the valve looks very similar, but not exactly the same, as the picture you posted above.
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California
Joel,
On my boat, the petcock under the heat exchanger is on the raw side of the system. I can only drain sea water from it, not anti-freeze.
Duane Ising - Past Commodore (2011-2012)
s/v Diva Di
1999 Catalina 36 Hull #1777
Std rig; wing keel, M35B, Delta (45#)
Punta Gorda, FL
http://www.sailblogs.com/member/diva-di/
[QUOTE=JAS;20229] Is there a way to reattach the butterfly wing to the post if it is spinning freely? [/QUOTE]
Other petcocks like that I have examined have the t-handle brazed to the shaft, and I don't see you being able too do that very effectively. JMHO.
Duane Ising - Past Commodore (2011-2012)
s/v Diva Di
1999 Catalina 36 Hull #1777
Std rig; wing keel, M35B, Delta (45#)
Punta Gorda, FL
http://www.sailblogs.com/member/diva-di/
Hmm, another published reason why I said what I did on your first post.
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)
Drain petcocks should only cost about $4. They are widely used on car radiators. Go on ebay and look for "Dorman petcock".
Nick Caballero
Retired C36/375IA Mk II Technical Editor
[QUOTE=newguy;20241]Drain petcocks should only cost about $4. They are widely used on car radiators. Go on ebay and look for "Dorman petcock".[/QUOTE]
True. However, if the issue is replacing one on one's engines, it becomes a completely different issue.
It is my experience that petcocks on our engines should be left in place and not touched. Their location and fragility is something that indicates that there are many other ways to deal with coolant drainage than using the petcocks.
Access. Handles coming disengaged. Blockage.
Need any more reasons?
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)
True. If you wanted to replace your petcock with something else, then just a pipe plug will do the trick. About $2 at your local hardware store.
Nick Caballero
Retired C36/375IA Mk II Technical Editor
You guys are right. I called a parts supplier for Universal engines and they quoted me a price about ten times lower than the price I suggested earlier. How I got that price in my head is now a mystery to me. All I know is that my mind is under the impression that I read it somewhere. Where that somewhere is seems to be just out of reach at the moment. But again, you guys are quite correct, petcocks are dirt cheap. Whether it is advisable to replace them goes way above my pay grade at this juncture in my boating career.
Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California