Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 08-06-2016, 18:03   #1
Registered User

Join Date: Nov 2015
Location: Chocowinity, NC
Boat: Pacific Seacraft Flicka 20
Posts: 13
1GM10 not happy

1gm10
We have a new to us (Fall 2015) 83 Pacific Seacraft Flicka with a repowered 1GM10 in 1999. After purchase we have replaced the complete cylinder head assembly (significant head corrosion and exhaust port blockage), impeller, engine anode, fuel lines, oil and fuel filters. Engine starts reliably but will only get to 2500 rpm in forward gear with full throttle. The engine does not smoke or exhibit any other problems but SOG is slow (I know it's not a speed boat) and way less than hull speed all the time (max 4 knots if lucky). Temps on the shaft/transmission are cool to the touch so we don't think there is a drive train problem.... engine is responsive to throttle and in neutral easily goes to 3600-3800 rpms so we think the tachometer is OK/fuel supply is OK. At this point trying to figure out what to do next.
Based on this site I have ruled out the hull (clean and repainted and launched in May 2016), the propeller is a two blade prop that appears original so it is not clear that it is over propped. So at this point I have two questions:
1) what additional things could explain this?
2) what are the effects to run the 1GM10 under the target RPMs of 2900-3000 while using full throttle?
Loving the Flicka in NC
__________________

__________________
CarolinaCalm is offline   Reply With Quote
Old 08-06-2016, 19:15   #2
Registered User

Join Date: Jan 2012
Location: Full time cruisers
Boat: Krogen 42
Posts: 252
Re: 1GM10 not happy

I take it this was purchased without a survey. I would go with an over prop issue.
__________________

__________________
----------------------------------
Terry
meridian28 is offline   Reply With Quote
Old 08-06-2016, 19:35   #3
Registered User

Join Date: Nov 2015
Location: Chocowinity, NC
Boat: Pacific Seacraft Flicka 20
Posts: 13
Re: 1GM10 not happy

It was surveyed but I was not able to attend. Survey stated that engine started, idled , and powered the vessel with no noted issues. Pretty weak. Later when we disassembled we found significant corrosion issues so the survey was useless to me wrt the engine but was thorough in all other respects.
I recieved one reply from a different site suspecting the throttle linkage with the thought that if the engine is not smoking then the linkage could be limiting fuel. I will chase that thought and the next will be the prop. Thanks for reply
__________________
CarolinaCalm is offline   Reply With Quote
Old 09-06-2016, 04:26   #4
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,583
Images: 240
Re: 1GM10 not happy

Greetings and welcome aboard the CF, CarolinaCalm.
__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is offline   Reply With Quote
Old 10-06-2016, 06:14   #5
Registered User

Join Date: Feb 2015
Location: Montreal
Boat: Paceship 29
Posts: 57
Re: 1GM10 not happy

Check out the props on other Flickas, on the hard. What is their pitch?
Are they 7",8", or 9"? What is yours? If you lowered your pitch an inch, you may end up with 2800-2900rpm. I'm tending to think your rebuild was good.
__________________
sony2000 is offline   Reply With Quote
Old 11-06-2016, 00:46   #6
Senior Cruiser
 
roverhi's Avatar

Cruisers Forum Supporter

Join Date: Aug 2005
Location: Kona, Hawaii, Carlsbad, CA
Boat: 1969 Pearson 35 #108 & 1976 Sabre 28
Posts: 6,005
Send a message via Yahoo to roverhi
Re: 1GM10 not happy

If the engine runs to 3600 rpm easily, it could be too small a diameter and/or pitch prop. Sounds like the engine is working fine. Unless the transmission is slipping, the only other thing is the prop. A Prop shop should be able to increase the pitch of the prop by an inch or more which shouldn't affect performance all that much if it is in fact currently the right pitch.
__________________
Peter O.
'Ae'a Pearson 35
roverhi is offline   Reply With Quote
Old 11-06-2016, 05:13   #7
Registered User

Join Date: Feb 2015
Location: Montreal
Boat: Paceship 29
Posts: 57
Re: 1GM10 not happy

Quote:
Originally Posted by roverhi View Post
If the engine runs to 3600 rpm easily, it could be too small a diameter and/or pitch prop. Sounds like the engine is working fine. Unless the transmission is slipping, the only other thing is the prop. A Prop shop should be able to increase the pitch of the prop by an inch or more which shouldn't affect performance all that much if it is in fact currently the right pitch.
__________________
sony2000 is offline   Reply With Quote
Old 12-06-2016, 19:42   #8
Registered User

Join Date: Nov 2015
Location: Chocowinity, NC
Boat: Pacific Seacraft Flicka 20
Posts: 13
Re: 1GM10 is happy again

Thanks to all that replied. Turns out it was a throttle linkage problem. Engine now is able to cruise along at 2900-3000rpm per Yanmar operating guidelines for continuous rating and also can hit the max rpm of 3400 for short periods.
__________________

__________________
CarolinaCalm is offline   Reply With Quote
Reply

Tags
1gm10

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Not happy with current wheel Beanctr Propellers & Drive Systems 1 23-06-2015 15:37
Happy New Year from a Happy New Member! Fazer1000 Meets & Greets 6 18-01-2010 11:51
Yanmar 1GM10 - White smoke, no start nickj Engines and Propulsion Systems 11 08-05-2009 08:44
winterizing yanmar 1gm10 cooling system tess Engines and Propulsion Systems 6 12-12-2007 16:32



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 11:29.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.