3GM30F Clean-up

Oct 26, 2008
6,043
Catalina 320 Barnegat, NJ
So far so good ...

Before:
IMG_3232.jpg


After:
IMG_6025.jpg

Primary objectives were to replace the standard pulley with serpentine pulley kit (courtesy Compass Marine), replace all hoses and replace the timing gear case gasket. In the process, I installed ...

New freshwater pump & new seawater pump
New sensors for water temp & oil pressure
New thermostat
New high pressure fuel lines
New chamber components in the cylinder head sockets for injectors
Cleaned & tested injectors
New suction manifold
New regulator lever assembly
New timing shims
Replaced every bolt, nut, washer & screw that I removed
Removed and cleaned the heat exchanger - but it was already free from any obstructions.
Replaced all the gaskets for any components removed.

I didn't replace the hoses to and from the water heater. I could not find any feasible way to pull those hoses thru the confined spaces. I was able to pull out enough excess hose to cut away several inches of beat up ends so they do look much better at least. I haven't installed the vented loop for the exhaust hose, but I have the new hose and loop to install now that I'm in the water. I have to fit a better location for the external regulator outside the engine compartment, but the wiring constrains the reach right now. I also have to make final adjustment to the governor.

Re-assembly went very well, thank you, until I put 2 quarts of oil in the coolant fill the evening before my scheduled launch! :facepalm: Has anybody done that?!?! I had the fill open and absent-mindedly just started filling ... the 2 fills are pretty much right next to each other. :banghead: Just before I started pouring a 3rd quart, I was wondering why the dipstick hadn't started to show any oil yet. :what: Several hours of draining and flushing and I was good to go. No issues getting from the travel lift to my slip at least. I'll drain it one last time after heating the coolant again.
 

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Dec 14, 2003
1,393
Hunter 34 Lake of Two Mountains, QC, Can
Great job Scott.
As for replacing the water heater hoses going to the engine here is a simple solution that I used. Worked perfectly and took very little time.
 

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Likes: Scott T-Bird
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
Scott, have you consider turning the SCW Pump (mod require use of YM pump bracket) around like those for YM Series engine? The pulley on inside and pump cover facing out. Makes it easier to check/change impeller.

Ken Y
 
Oct 26, 2008
6,043
Catalina 320 Barnegat, NJ
Scott, have you consider turning the SCW Pump (mod require use of YM pump bracket) around like those for YM Series engine? The pulley on inside and pump cover facing out. Makes it easier to check/change impeller.

Ken Y
I didn't know there is a way to do that!:facepalm: Is it simply a different bracket? The impeller would be spinning in the opposite direction, no? Would that matter? I guess it might not.
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
Great job Scott.
As for replacing the water heater hoses going to the engine here is a simple solution that I used. Worked perfectly and took very little time.
If you are replacing the hose, might as well go full-on "pimp-my-ride" and use colored hoses...:pimp::pimp::pimp::pimp::biggrin:

1623778789967.png
 
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Likes: Ward H
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
Gee, whaddya think? Could it be as easy as maybe switching the inlet and outlet hoses on the pump? What drives the pump?
Yes it is simple as switch the inlet & outlet hoses around although the length are different hence may need replacing. Someone on this forum or Sailnet forum done the modification. I'll try get info and post here.

PS: can I attach zip file here?

Ken Y
 
Last edited:
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
Here is the photos for the modification. These are not mine but downloaded from the a forum.
 

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Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
I didn't know there is a way to do that!:facepalm: Is it simply a different bracket? The impeller would be spinning in the opposite direction, no? Would that matter? I guess it might not.
Just need to swap the hoses around that's all. I actually bought the required parts for this modification and did it half way and reverted it as i had other pressing issue to manage.:facepalm: Since then, didn't come back to do the mod. Now I'm thinking if should restart this mod as the boat won't be going anywhere with this covid19 travel restriction.:(

Ken Y
 
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
Here is the photos for the modification. These are not mine but downloaded from the a forum.
Looks like inspecting the pump rotor is a breeze with the pump body on the exterior side of the engine. Any idea who makes the pump bracket #1288990-42181 ? No luck under Yanmar. If I can find that one, I can find the bracket for the 2GM.

If not the manufacturer, then maybe a link to the forum post from which you pulled the pictures.
 
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
Looks like inspecting the pump rotor is a breeze with the pump body on the exterior side of the engine. Any idea who makes the pump bracket #1288990-42181 ? No luck under Yanmar. If I can find that one, I can find the bracket for the 2GM.

If not the manufacturer, then maybe a link to the forum post from which you pulled the pictures.
The bracket is from Yanmar 3YM20/30 series engine. Part Number quoted in photo seems mistake.
There will be minor alignment of the pump pulley to crankshaft pulley but that shouldn't be difficult with using washers to pad up somewhat.

Ken Y
 

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Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
Part Number quoted in photo seems mistake.
I see said the blind man :doh: ! Use the number in the file name (-42151) rather than in the photo (as you said) and it turns out everyone and their dog sells them. Just have to works backwards for a 2GM pump bracket.

Thanks @Ken13559 .
 
Oct 26, 2008
6,043
Catalina 320 Barnegat, NJ
I also see in my photo that I failed to connect the other end of the breather tube! :facepalm: Just another task before finally getting to the finish line! I didn't think about it until I read a post on another thread that mentioned the breather tube.