Inboards that start running too hot?

[Geek_Guy]

I just did mine for the first time. It really wasn't nearly as hard as it looked. Look at the front top left of the engine. You should see a cap with 4 bolts. Undo the 4 bolts and the cover should come right off. Then inside you'll see the core. It'll be a round thing with lots of tubes in it. If you are really lucky it may just slide out to the front. If not things may get interesting, or you may just take the easier road and do what several above have suggested. To just clean out the tubes and leave the core in.

Since I'm a glutton for stupid extra jobs. I tried to pull it out. Mine wouldn't even wiggle. I took off the back cover. But couldn't get anything back there to get some pressure on the core. Ended up taking the entire exchanger off. Which was actually easier than trying to force out the core in place. It was way easier to work on the unit on my workbench than in the boat. But you have that part easier. My Yanmar mechanic suggested taking a piece of lumber that just fits into the chasis and pounding at the core. He said that sometimes they will move and frankly sometimes they won't. Since my exchanger isn't available from Yanmar anymore I had little to lose. But after a few medium blows with a hammer on the wood it would wiggle a little. Started pounding it in and out and it finally freed enough to allow it to be extracted. -------If it's tight after you get it a little loose, pound it out toward the back. I found after I was done that there is a sleeve about an inch from the front. I was struggling the core through that sleeve the entire length of the core. If I had gone back it would have cleared the sleeve in a very little space and then would have been completely loose.

Then I cleaned the core and the exchanger chasis with a great product suggested by a nice man on this site. After a couple hours it looked brand new. I'll find the name of the product and post it. Put everything back together and put back on boat.

If you have any basic mechanical skills it is really very doable. Things make a lot of sense when it comes apart. Which is the best part of the project. There are o rings on each end of the core, and gaskets for each end. If you take the whole thing off, then you'll also need gaskets for the exchanger to engine, and for the exhaust elbow. Since I'm not in the league with the guy that posted he can measure and get the o rings elsewhere, I just got it all from the Yanmar dealer.

[sailah]

Originally Posted by softdown

Closest Yanmar "dealer" is over 200 miles away. Colorado is a poor sailing state. This dealer works with industrial engines, I'll bet they have some experience with Yanmar agricultural products. Almost none with marine products.

Use the Google ** my friend

One trick I found useful is I have an email chain to myself in my Gmail just for my boat. When I find things like oil filters, raw water impeller, zincs etc cross reference numbers, I'll add it to the email chain. Since Gmail can search my entire email account in 2 seconds I always have the info at my fingertips.

Things like oil filters are easy to find at any auto parts store if you have the number in your gmail.

So I'll type in the gmail body:

Oil Filter Cross Reference Yanmar 2GM

And then copy/paste this webpage too

YANMAR 119305-35151 - Alternative oil filters

So now when I'm standing in autozone I just search "Yanmar 2GM oil" and they only have Purolator, Fram and Bosch filters I can find one to fit.

[Geek_Guy]

The cleaner was called: "Barnicle Buster".

Very cool. Just dump in the metal part, and it bubbles and after a couple hours the metal looks bright, shiny, and brand new.

Other's said that muriatic acid worked as well. But I'm a big fan of splurging for a specific product for the exact task at hand.

[leftbrainstuff]

Check temps in and out of both the raw water and closed loop cooling system. Also check for flow.

These simple checks will highlight the problem area.

Pulling the engine first seems odd.

[softdown]

Originally Posted by leftbrainstuff

Check temps in and out of both the raw water and closed loop cooling system. Also check for flow.

These simple checks will highlight the problem area.

Pulling the engine first seems odd.

Bought the boat and trailer off of a very nice older couple that quit sailing eight years ago. At the price, I consider it a donation to get out of their slip fees. Much to my chagrin, the engine is missing the entire heat exchanger assembly.

I have emailed the gentleman and have crossed my fingers that he can locate the heat exchanger. I got both the best and the worst deal imaginable when I got this boat and trailer.

Adjusting the trailer to accommodate the 4' draft has costs me over $700 so far. Plus several days work. Kind of fun, kind of exciting, kind of a bummer. Extremely hard work replacing rust welded 1/2" and 5/8" bolts.

I still think the previous owner is a heck of a guy and hope that things work out. We all get old and move into gentler pursuits. And lose things...

[sgancarz]

The heat exchanger may not be missing, but rather was never there to begin with. This could be a raw water cooled engine that never was designed to have a heat exchanger. Yanmar made two versions of many of their marine engines. Those that were fresh water cooled (engine designation ended with 'F') and those that were not (did not have and 'F' at the end of the engine designation). Example 2GM20 vs 2GM20F.

[jimbunyard]

Originally Posted by sgancarz

The heat exchanger may not be missing, but rather was never there to begin with. This could be a raw water cooled engine that never was designed to have a heat exchanger. Yanmar made two versions of many of their marine engines. Those that were fresh water cooled (engine designation ended with 'F') and those that were not (did not have and 'F' at the end of the engine designation). Example 2GM20 vs 2GM20F.

The above is good advice.

Don't waste your money on an aftermarket 'manual'; the real thing is available for free on-line,

http://www.google.com/url?sa=t&rct=j...K1NHjGdobuUXYg

Have a look at it and figure out for sure what you have before buying anything more. Filters can be had for less than half Yanmar's prices from the internet, and possibly the local autoparts store.

It would also be a good idea to start the engine on the floor to make sure that it actually runs before you spend anything on it. This is very easy to do, if you're nervous about it try and find someone to help you, if you're adventurous, you-tube it and see how other people do it.

If you're still removing rusted bolts, the easiest way is usually cutting them off with a 4 1/2" grinder and a 1/16" thick cutting disc...

[softdown]

Originally Posted by sgancarz

The heat exchanger may not be missing, but rather was never there to begin with. This could be a raw water cooled engine that never was designed to have a heat exchanger. Yanmar made two versions of many of their marine engines. Those that were fresh water cooled (engine designation ended with 'F') and those that were not (did not have and 'F' at the end of the engine designation). Example 2GM20 vs 2GM20F.

Interesting, I'll check it in the morning. They lived and sailed on San Francisco Bay, not sure why they would buy the freshwater model. We shall see.