After I replaced the impeller in my Sherwood raw water pump was no water in the exhaust. After several times of reconfiguring said pump my trusted mechanic examined the engine - a M35BC - and showed me that the one of the two cams that the spade shaft of the Sherwood attaches between was damaged and therefore did not cause the impeller to rotate. This mechanic suggested an external water pump attached to the lower right side of the front of the engine near the oil filter and double up the main shaft pulley to operate it.
Anyone ever experience this?
Thanks
Tom Bolen
SPIRIT, #1780 MKII, TR/WK
Northport, NY
631-896-7162
Sounds interesting. I had suggested just that to someone else some time ago. Do you have photos? That would help. You may consider making sure that there is enough room inside the engine cover.
Sail La Vie 1999 Catalina 36 MKII, M35B-17031, Coyote Point, San Mateo, CA
About Sail La Vie
The prognosis was decided on 5/21/15, and I searched this forum for anyone else who had this external pump installed. We checked under the hood and there is room (surprisingly!!)LOL.
I will document this installation to be posted.
Tom Bolen
SPIRIT, #1780 MKII, TR/WK
Northport, NY
631-896-7162
Given this current rw pump thread and the great groundbreaking done by C36 owners in removing the crappy Sherwood pumps and replacing them with simpler, better Oberdorfers, this seems a complete overkill.
https://www.catalina36.org/forum/technical-discussion/raw-water-pumps
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)
[quote=stu jackson c34]Given this current rw pump thread and the great groundbreaking done by C36 owners in removing the crappy Sherwood pumps and replacing them with simpler, better Oberdorfers, this seems a complete overkill.[/quote]
The original enquiry stated that the engine cam is damaged and does not turn the pump, so changing to a different model would be of no help.
Nick Tonkin
*Former* Website Administrator, C36/375IA
*Former* owner, C36 tr/fk #255, Santa Barbara, CA
Stu
I see you have the 25xp does this pump work for our engine a 25xp also. My Sherwood is working around 1000 hrs but I like the ease to change the impeller on the other so might change out and keep the sherwood as a spare
Bill Miller
S/V Lorraine
Pacific Northwest,Sound Sound
Grapeview,Wa
1990 Mk1
Bill,
I have an M25, not an M25XP.
Yes, the Oberdorfer works with the M25XP. They are exactly the same engines, except the XP has 2 more HP, a bigger OEM 3" HX and the upgraded alternator bracket.
Except for the 2 HP, my engine is the same, since I installed the larger HX and the VERY NECESSARY alternator bracket upgrade.
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)
Overkill? Guidance like that makes me glad I renewed my subscription for three years.
It is my understanding that the female end of the cam shaft that the single blade of either the Sherwood or the Obendorfer (sic) attaches between was damaged somehow and therefore cannot rotate either impeller.
I had no issues with the pump at all until I decided to replace the impeller as preventive maintenance. The mechanic suggested to install a Yanmar 3GM rwp as it was a cheaper to install this pump then to replace the cam shaft.
[quote=tangled]
I had no issues with the pump at all until I decided to replace the impeller as preventive maintenance. The mechanic suggested to install a Yanmar 3GM rwp as it was a cheaper to install this pump then to replace the cam shaft.
[/quote]
Really?? I'd be looking for a new mechanic...
It would be easier and cheaper to install a belt-driven pump - but not a new engine!
It's even possible to do yourself.
https://www.catalina36.org/forum/technical-discussion/dreaded-cam-shaft-...
http://sv-silhouette.blogspot.ca/2013_12_01_archive.html
---- Howard & Linda Matwick ----
--- S/V "Silhouette" - Nanaimo, BC ----
--- 1999 C36 MkII #1776 M35BC ---
[quote=HowLin][quote=tangled]
I had no issues with the pump at all until I decided to replace the impeller as preventive maintenance. The mechanic suggested to install a Yanmar 3GM rwp as it was a cheaper to install this pump then to replace the cam shaft.
[/quote]
Really?? I'd be looking for a new mechanic...
It would be easier and cheaper to install a belt-driven pump - but not a new engine!
[/quote]
I'm pretty sure his mechanic was recommending the belt-driven pump made by Yanmar, not a new Yanmar engine.
Nick Tonkin
*Former* Website Administrator, C36/375IA
*Former* owner, C36 tr/fk #255, Santa Barbara, CA
Aww, I see. Think you're right Nick...
---- Howard & Linda Matwick ----
--- S/V "Silhouette" - Nanaimo, BC ----
--- 1999 C36 MkII #1776 M35BC ---
[quote=tangled]Overkill? Guidance like that makes me glad I renewed my subscription for three years.
[/quote]
He was saying that it would be overkill if all you wanted was to switch from the Sherwood. But if the cam is damaged the Oberdorfer wouldn't be any better. So your mechanic is probably right and it's not overkill.
Nick Tonkin
*Former* Website Administrator, C36/375IA
*Former* owner, C36 tr/fk #255, Santa Barbara, CA
Thanks for the translation Cap'n Nick. I plan to photo and document this as best as possible so this website has it on file.
Tom Bolen
s/v SPIRIT
36MKII, #1780
Northport, NY
It was my misunderstanding that the broken bit was outside the engine. Sorry. Good luck.
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)
No Worries Stu. Bob Hansen of Hansen Marine, a Universal Distributor in Marblehead, MA., was very helpful with this process. Hansen advised that he has seen this before many times on a Universal and advised that this second pulley on the crankshaft of SPIRIT's M35BC Universal will not harm the harmonic balance of said engine. Hansen also advised that the use of a Yanmar 3GM sea water pump is an excellent choice, will push enough water, and he sees no issues with the engine. The parts are scheduled to arrive by June 8, or June 9. And the check is in the mail!! LOL
I am hoping that my next "Big Problem" will be to slow down the mechanic so I can properly document this for our website.
Stay Tuned.
Tom Bolen
Spirit, 36 MKII, #1780
Northport, NY