Issues with Yanmar 2GM

Status
Not open for further replies.
T

Tim McCarty

Anyone who has been on this site for awhile knows about past issues with the 2gm. One: it can be really cranky to start, and, two: though I've not run into this problem (YET), it has a tendancy to overheat. I would like to address both problems with this thread. I plan on running the engine in the cradle in April (before launch), so, I can, hopefully, solve the hard starting problem (yes, I will be hooking up freshwater to the intake). First thing I'd like to do is bleed the fuel line...is this a good place to start?? Mackboring, are you listening? Next, can anyone give me some insurance against the overheating problem. Again, I've not experienced this, however, have only had the boat sine 9-02 and it's been in a cradle since 10-02. From what I've read in other threads, it is primarily a problem after the engine has been running for a few hours. PS: I noticed that this engine has a coolant recepticle...when I checked mine, it was empty. I will be adding new coolant in the spring. Can someone with some experience tell me how they dealt with the problem... My former, and, much loved boat, was an '82 Hunter 27 with a Yanmar 1gm, and, after 7 years, never had one problem with it. Why so much trouble with the 2GM??
 
W

Wesley

No trouble with 2001 2GM diesel

I have a 2001 Hunter 320 with a 2GM diesel and have not had any trouble in 2 summers of use. It starts quick every time. I have about 70 hours on the engine so far. Ran 20 hours non-stop this past summer.
 
J

Jim Bessinger

2gm20

Ive had mine now three seasons, other than cold weather starts easy and runs fine, never has overheated.
 
T

Tom

Mixing Elbow

For some reason the mixing elbow tends to carbon up after relatively few hours on this engine. This can cause loss of power and overheating. If you are only using your engine to get in and out of the harbor you should probably check/clean every couple of seasons at a minimum. Tom H310
 
R

Rip Edmundson

No trouble with Yanmar 2GM20F after 4 years

I have a 1987 Hunter 31. The engine starts instantly and never has overheated. We have run it for 10 hours straight crossing Lake Michigan with no problems. I think if you maintain it properly, you should have a reliable engine for many years.
 
B

Bill

class

Tim, I recommend you take the Yanmar class put on at Mack Boring. It will answer a lot of your questions. BTW not sure what you're referring to by coolant recepticle. On fresh water cooled engines, there is a plastic container level with the top of the heat exchanger. It's the sub tank (one of the things I learned at the class recently), and it should be low in cold conditions since it an expansion overflow tank, not a refill tank. Its level does not indicate whether or not topping up is needed. Hope that helps. Good luck.
 
T

Tim McCarty

re: the sub tank

Thanks Bill, and, everyone else. Unfortunately for me, Mack Boring does not offer classes in my localle. I would LOVE to take one of these classes! Anyway, regarding this sub tank for fresh water cooled engines, should I not fill it with SOMETHING, as, it is completely empty?
 
R

robert

yanmar

have a 29.5 also. Only time it overheated was when a latex birth control device was picked up by the raw water intake, and clogged the flow. You need to flush the coolant system with new 1/2 strength antifreese, and fill that cannister about 1/2 the way up. to allow for expansion. My prior boat was also a 27 hunter with a 9hp yanmar 1 cilinder. It worked like clock work but sounded like marbles in a metal blender. good luck
 
T

Terry

Hi Tim, lots of good advice so far...

We ran our 2GM just over 300 hours in three seasons and never had trouble with it. I kept the expansion tank (the white plastic bottle above the engine) between the low and full marks with coolant. When the engine was cold I would push the throttle to maximum during cranking. It took about five seconds before she fired up. As soon as I sensed she was starting to fire I would reduce throttle to avoid over running the engine. Terry
 
D

David Priestly

Yanmar 2GM overheating

Tim, Address these five areas and I would bet that the overheating problem is solved: 1. Check / change thermostat 2. Change raw water impeller (will need new gasket) 3. Pull heat exchanger and clean (will need new O rings and gaskets) 4. Remove mixing elbow and clean 5. Flush out system and replace with new coolant Of course I assumed that you have checked the thru hull fitting, hoses, and raw water strainer. I would suggest purchasing a Seloc repair/service manual for the 2GM (Amazon.com) to guide you along the way. This project should take an entire weekend Good Luck! David '88 H33.5 "South Wind"
 
A

Alan Kibbe

2GM20 Overheating

I used to have a 29.5 with the 2GM20. The engine would overheat when the raw water intake hose, between the sea cock and the raw water strainer, became clogged with eel grass. The fix was to replace the factory-supplied hose barbs, which narrowed the diameter of the water path to 1/4", with full-flow barbs which allowed the hose diameter to be increased. The eel grass then found its way to the strainer, rather than getting stuck in the intake. Daily cleaning of the raw water strainer then prevented further overheating.
 
T

Tim McCarty

Thanks to all for the great suggestions

Again, I have yet to experience any overheating problems (just heard that this could happen). I do experience difficulty starting. I do have a service manual for this engine (it acutally covers the 1, 2, 3 and 4GM).
 
B

Bill Murray

overheating and starting

I have a 1985 Hunter 29.5 -Hull #175 - "Good Faith". I have had very few problems with the 2gm in the 8 seasons I have operated the boat. The engine has always started without trouble - even in cold weather although you need to give it a good throttle when cold to get it going. once started throttle back to idle. Otherwise, use only clean fuel - be sure! Get absolutely religious about this and you will avoid most problems that others encounter. My engine has only overheated when we kept it in Lake St Clair and encountered a lot of weeds - grasss and duck weed. These would get sucked into the intake and clog the strainer. Voila - overheating. I have run it as much as 14 hours at 3000 rpm without overheating. Now we dock the boat in lake Huron and have had zero problems in that very clean environment. I have added temp and oil pressure gauges. You get lots of peace of mind and a good constant check up - if you care to pay attention to them. If you maintain this engine properly, you should have a reliable engine for many years. You can take a class on the care and feeding of this engine. The first year I had my boat I found a great class that was taught in the Bay City area - go there for a weekend - it was a great program. I can't remember the details but I think if you contact Warren at Blue Water Marine in Mt Clemens (810 468-6960) he can tell you - that is where I found out about it. Good Luck with your h29.5 - I love mine. If you want more info - email me. I am in the directory on this site. Bill Murray S/V Good Faith h29.5
 
Status
Not open for further replies.