Yanmar 4JH3E Oil Cooler

[cetacean67]

My Oil cooler on a Yanmar 4JH3E has just disintegrated and caused a lot of water damage and hassle and expense. We think this is due to electroltyic action, presumably because of little, if any, protection by the anodes on my Jeanneau SO 40.3 (2004).
Can anyone shed any light on this issue, has it happened to anyone else, surely an oil cooler should last more than 5 years? How do I prevent this happening again?
I'm also surprised that the manufacturuers haven't warned owners about this.
Any help would be appreciated.

Thanks, Phil

[stormsurf]

I've heard that this is a common problem on Yanmars. I went ahead and had my coolers replaced with a separate type that I had to mount on a fabricated bracket. The new ones have 2 huge zincs which I change annually. They are still looking like new after 4 years and, with the different bracket, I can get to the dip-stick on the transmission much easier.

BP

[poppyduc]

Originally Posted by cetacean67

My Oil cooler on a Yanmar 4JH3E has just disintegrated and caused a lot of water damage and hassle and expense. We think this is due to electroltyic action, presumably because of little, if any, protection by the anodes on my Jeanneau SO 40.3 (2004).
Can anyone shed any light on this issue, has it happened to anyone else, surely an oil cooler should last more than 5 years? How do I prevent this happening again?
I'm also surprised that the manufacturuers haven't warned owners about this.
Any help would be appreciated.

Thanks, Phil

I have a Hunter 41 4 years old and heading for same problem, I can't seem to stop the corrosion on the cooler and believe it has a very limited future.
How did you fix it or just replaced the part which I have been told will be very costly
Steve

[MarkJ]

The anode need changing each year.

The problem is NOBODY EVER TOLD NOBODY!!!!!

Apart from that its damn hard to change!

If you are lucky there is clearance to unscrew it and insert another.
If you are unlucky you have to unbolt the whole thing and wriggle it around.

If the anode wears oout then the next thing that wears is the solder at the 2 ends of the oil cooler because of the electrolysis.

You need to remove the oil cooler (a prick of a job) and take it to the auto radiator shop and they will recondition it for you.


If you are not handy with a spanner, really handy, then its time to call the friendly yanmar mechanic and see if they will do it for a fixed price


Mark

[poppyduc]

Where is this anode I asked my local Yanmar agent and he said they did not have one on that engine???
He did not seem to interested as the boat is at another port

[MarkJ]

Its the brass bolt sticking out of the oil cooler cylinder.

Unscrew it.


Its like a pencil about 2 inches long.

[cetacean67]

Thanks All, and particularly Mark.
I'm now getting the picture, but it's not a good one. Replacing the cooler is very expensive. I've also been told by two Yanmar agents that this model does not have anodes. Has anyone taken it up with Yanmar?
It's crazy that nobody seems to know about this. In a worse case scenario, if it breaks down it could have serious consequences.
I am continuing the research - next stop, Yanmar.
Yours frustratedly, Phil

[Boracay]

Have you considered one of the generic oil coolers?

[MarkJ]

Originally Posted by cetacean67

. Replacing the cooler is very expensive.

Yes, Phil. But not repairing it.

Take the thing, or whats left of it to an auto radiator repair place. They do them all the time. For them is an $80 job... all brand new, all the impeller fins dug out, acid bathed and painted.

yes, thats where those lost impellor fins end up!


Mark

[Chief Engineer]

I ran into a guy today that walked up to me with the dripping cooler in his hand....the plug was pinkish looking.....I told him about the pencil zinc....or else he could bond it to the engine? Gordon the Magnificent?

[chrisjs]

I am a bit confused by this discussion topic. I have a Yanmar 4JH3E mated to a Yanmar SD50 saildrive as back-up propulsion on my trawler. Since I have owned the boat, I have understood that there are no internal zincs on this engine or saildrive. The only zincs are mounted behind the prop on the saildrive and on the prop. No zincs are shown in any of my Yanmar documentation. After reading this discussion I again contacted Mack Boring in NJ to ask about zincs. The technical person there checked diligently though their documentaion and confirmed yet again that there are no zincs.
If there is a zinc on the 4JH3E oil cooler where exactly is it??

chrisjs

[poppyduc]

Does this engine have any zinc anodes fitted on it at all??

Originally Posted by chrisjs

I am a bit confused by this discussion topic. I have a Yanmar 4JH3E mated to a Yanmar SD50 saildrive as back-up propulsion on my trawler. Since I have owned the boat, I have understood that there are no internal zincs on this engine or saildrive. The only zincs are mounted behind the prop on the saildrive and on the prop. No zincs are shown in any of my Yanmar documentation. After reading this discussion I again contacted Mack Boring in NJ to ask about zincs. The technical person there checked diligently though their documentaion and confirmed yet again that there are no zincs.
If there is a zinc on the 4JH3E oil cooler where exactly is it??

chrisjs

[Chief Engineer]

Let me put it this way...you have an oil cooler with dissimialr metals in it.

It is isolated from the engine block by hoses.....with seawater running through it, you are going to have electrolysis. If there is no zinc....you will have to bond it with the engine which is (hopefully) protected with a zinc. I have seen some coolers with a small tab for a bonding wire....or you could use a hose clamp and squezze and bonding wire to the body of the cooler.(have to remove the paint in that spot)

[MarkJ]

Originally Posted by chrisjs

If there is a zinc on the 4JH3E oil cooler where exactly is it??

chrisjs

Originally Posted by poppyduc

Does this engine have any zinc anodes fitted on it at all??

You two as soooo like Nicolle!

I can't take a photo of the damn thing because the aft cabin is full of crap due to the 2 bloody new solar panels being in there... so now there is no space we have loaded junk in the aft cabin and can't get to the rear of the engine.

Below is a photo of the spare zinc I bought........ I WOULDN'T BUY IT UNLESS THERE WAS A PLACE TO SHOVE IT, NICOLLE!!!!!!!!

[cetacean67]

Thanks All,
I'm learning all the time, but unfortunately I haven't been able to get to my boat recently to check engine and/or the owner's manuals (long story). From what 'Chief Engineer' says we should all be checking for the presence of zincs or suitable bonding - I'm not sure Yanmar or the boat manufacturers stress this sufficiently.
I now have a new cooler fitted (at a cost of around £600), but I am not convinced that it is suitably protected even now. Even the 'professionals' I've spoken to seem pretty vague about these issues.
I'm thinking about swallowing the anchor and buying a motorhome - rock and a hard place or Frying pan to Fire?
Cheers, Phil