Deprecated: Function set_magic_quotes_runtime() is deprecated in /var/www/vhosts/tartan37.com/httpdocs/t37forum/common.php on line 88 Tartan37.com • View topic - Changing Pencil Zincs W50

Tartan37.com

Tartan 37 Owner's Forum - Ride the wind, but look good doing it!
The time is 28 Mar 2024 05:16

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 18 Posts ]  Go to page 1, 2  Next
Author Message
 Post subject: Changing Pencil Zincs W50
PostPosted: 07 May 2014 10:37 
Offline
Skipper

Joined: 24 Sep 2013 09:20
Posts: 393
This may be on here somewhere, but I couldn't find a thread that had detailed info. I'm a newbie with diesel engines, and this will be my first time checking/changing the zincs. Am I right that they are both accessed from the port quarter berth (remove panel)? I have looked at the engine diagrams, but not while looking at the engine (boat is 1 hour away and heading down on Sunday). I guess all I really have ascertained is locate on heat exchanger and oil cooler, close sea cock, remove with a socket wrench, determine correct size and length (possible cut with hack saw), and replace. Does anyone have the size or sizes (seems like I read they were different sizes) so I can pick these up at West Marine on my way down? I saw a pencil zinc in the chart table from previous owner. I am guessing this one may match, but it had teflon tape on the threads, and I read this was a no no? I have also read that water will be coming out of system when I remove these. Is that true for both zincs? Do I just use pads to catch the water? Small bucket? How much water? Do you try to stop by changing quickly? Does something have to be done to bleed the system at the end or does opening the sea cock and starting the engine do everything needed? Answers, tips, tricks, what am I missing, known hassles/issues appreciated. Thanks, Zach

_________________
Zach Duncan
SV Holiday
Hull# 280


 
 Profile Email  
 
 Post subject: Re: Changing Pencil Zincs W50
PostPosted: 07 May 2014 16:11 
Offline
Skipper

Joined: 29 Dec 2006 09:38
Posts: 656
These are really decent questions. I am sorry that I cannot give your more information, but here is what I recall.
Yes. you need to shut off the intake through hull fitting while doing this. Theoretically the zincs are beyond the pump which should hold the sea out, but you do not not know. There is not much sea water in everything, so I just let it run into the bilge. It is not a lot of volume.
Generally, you will find the zinc in the main heat exchanger more wasted than the one in the oil cooler, but this depends on the the PO. I would strongly suggest that you remove the end cap from the heat exchanger and look to see how clean it is in there. Typically, this is where old vanes of raw water pumps and the remains of zincs collect. An inspection will tell you a lot about the condition of your engine and the previous owners' attention to maintenance. If it is really crusty, I suggest you remove it and get it cleaned and tested by a reputable radiator shop. IMHO, this is the weakest part of the W50. Be extremely careful to align the cap with the dividing line as you will definitely have problems of overheating if you do not. Look inside the oil cooler and see what it looks like---replace it.

If this is a new boat to you, I strongly suggest you take your time with these two efforts. It is not just the zincs, but the flow through the coolers that is the life blood of the W50. If you take care of this and the exhaust elbow, change the oil, and have a properly pitched prop--these engines will run for a very very long time

Ray
Velera #373


 
 Profile Email  
 
 Post subject: Re: Changing Pencil Zincs W50
PostPosted: 10 May 2014 05:43 
Offline
Skipper

Joined: 21 Oct 2006 15:36
Posts: 268
I totally agree with everything that Ray said above but can add some additional tips/suggestions:

Be very careful when you reinstall the rubber end cap on the raw water Hx. As Ray said, the divider plate needs to be perfectly aligned with the groove in the rubber cap. In my opinion, it's too difficult to do with the Hx installed on the engine so I only do it with the Hx removed for cleaning. This may be my incompetence, but be very careful if you try. If you don't get it right, the engine will overheat.

I have have 2 Hxs that I swap about every 4 years. One is the older version with the rubber end cap. The second is a newer version with a gasketed, easily removed/reinstalled end cap - a much better design. However, a standard length zinc is too long and needs to be shortened by about 1/2" or you'll damage the divider plate for the newer version.

The raw water Hx zinc has a very short life expectancy. I need to replace mine twice a season.

You shouldn't use any sealant when installing the zincs. If tightened sufficiently, they won't leak and the sealant could hinder the electrical contact.

I think the raw water Hx zinc is 3/8" but I just measured the OD of its pipe threads with a caliper. It's 1/2". The lube oil cooler is the next larger size.

I access the lube oil cooler zinc from the stbd side. Use a little caution here. It seems, on my boat, that the zinc swells (i.e., gets pasty) sufficiently that at times, if I'm not careful, it gets stuck and breaks off when I try to remove it. If that happens, I remove the HX and try to remove it while out of the boat. Typically, the remaining part will fall into the HX, which makes it very hard to remove....but you need to get it out!!!

Hope this is helpful.

_________________
Jim Voelxen
Odyssey #191
Home Port: Osterville, MA


 
 Profile Email  
 
 Post subject: Re: Changing Pencil Zincs W50
PostPosted: 10 May 2014 10:47 
Offline
Skipper

Joined: 24 Sep 2013 09:20
Posts: 393
Thanks for all that info. I'm going to try and head down tomorrow and take a look at it. If come up with any more issues, will be sure to ask more questions. Thanks again, Zach

_________________
Zach Duncan
SV Holiday
Hull# 280


 
 Profile Email  
 
 Post subject: Re: Changing Pencil Zincs W50
PostPosted: 12 May 2014 13:45 
Offline
Skipper

Joined: 24 Sep 2013 09:20
Posts: 393
I think I had a pretty successful attempt at my first try on pencil zinc changes. I attached some pictures so hopefully with all our comments too, will be helpful to others. The sizes on the label at West Marine of the 2 zincs are 1/4 and 3/8. They are currently $3 and $4 respectively for the spare zinc without the nut and around $7 if you buy the whole thing. I figured out what the previous owner had done with the teflon tape on the one in the oil cooler (larger of the two). He had put it on the upper threads and then not shortened it so that some threads touched, but the top threads stuck out. Don't know if this is a good idea or not. Didn't notice any water leaking from there before the change. I cut probably a little more than a half inch off the larger zinc that goes in the oil cooler with a hack saw. Took a while but then again my dull blade and just holding the zinc with my hand on top of a dock piling was probably the culprit there. I removed most of the teflon tape from the threads. You can see from my picture of the oil cooler that the zinc still did not go all the way in. I was cranking on it hard enough with the wrench that it was moving the oil cooler, and I was worried that it might damage something. Anyone else experienced this? When I ran the engine afterward no water came out. Thoughts here? Is it ok to leave it like I did? I also did not shorten the zinc that went in the heat exchanger. You can see from the picture that the new zinc is the same length as the old zinc. So, I thought I didn't need to shorten that one. Is that correct? I ran into the same thing again. It did not go all the way in (see pic), and I didn't want to damage anything by cranking too hard. Again, it was dry when I ran the engine afterward. Both I could have tightened further, but with much force. Thoughts here? Check the pics with the used zincs. If those with more experience could comment on whether I changed these about right, too early, or too late, it would be much appreciated. You can see corrosion in the pictures at the hose connections near the zincs. Is that normal? I cleaned the corrosion afterward with Coca Cola and a brush. The water that came out when removing the zinc wasn't very much, and as suggested, I just let it drain. It goes into the tub below the engine, and then I wiped it up with absorbing pads afterward. Check out my picture of the heat exchanger. Would this be considered the newer version? The other had been described as a rubber cap, which this doesn't seem to be. I didn't remove it and check inside or look inside the oil cooler due to time constraints, but I have that on the list to do. I accessed both from the port side. I'm fairly small in stature and can sit down next to where my batteries are with my feet down next to the prop shaft. Simply starting the engine after all is replaced gets the flow of water back going after the draining of the system. Don't forget to reopen the sea cock. One other note: make sure to turn the battery selector to the off selection. Something right above the zinc in the oil cooler shocked me! Any other thoughts comments?


Attachments:
IMG_20140511_173430_122.jpg
IMG_20140511_173430_122.jpg [ 837.85 KB | Viewed 0 times ]
IMG_20140511_173345_238.jpg
IMG_20140511_173345_238.jpg [ 904.91 KB | Viewed 0 times ]
IMG_20140511_173313_998.jpg
IMG_20140511_173313_998.jpg [ 702.88 KB | Viewed 0 times ]

_________________
Zach Duncan
SV Holiday
Hull# 280
 
 Profile Email  
 
 Post subject: Re: Changing Pencil Zincs W50
PostPosted: 12 May 2014 19:55 
Offline
Skipper

Joined: 29 Dec 2006 09:38
Posts: 656
You appear to have the new heat exchanger and you should be happy about that. Looks to me like you did everything just right. Also, it appears that the previous owner maintained the zincs well and that bodes well for the rest of the engine and boat--those zincs have not been in there very long.

Ray
Velera


 
 Profile Email  
 
 Post subject: Re: Changing Pencil Zincs W50
PostPosted: 25 May 2018 09:30 
Offline
Skipper

Joined: 25 Apr 2016 10:25
Posts: 185
I'm trying to figure out which size zinc for the Oil cooler that I need to purchase. I have traced down the 1/4 NPT x 1-3/4" for the 11885 part number on the raw water heat exchanger.

From the above topic do both of them need to be cut off about 1/2 an inch or just the raw water heat exchanger?


 
 Profile Email  
 
 Post subject: Re: Changing Pencil Zincs W50
PostPosted: 26 May 2018 10:48 
Offline
Skipper

Joined: 29 Dec 2006 09:38
Posts: 656
As I recall, you need to cut down the zinc for the main heat exchanger, but not the one in the oil cooler. Having said that, you have a different main heat exchanger—at least the end cap is the new improved version. So I think you are fine. I would someday take the end cap off to see if there is stuff in there (old impeller blades find their way here). Also, my experience over several thousand hours is that the oil cooler is much more likely to clog (it is really hot in there) and it might not be able to be flushed—even my an experienced radiator shop (if you can find one in this “replacement” age.
You are doing really well with getting acquainted with your diesel. When I was out cruising for a few years, I was shocked at the number of people who left the dock for world cruises with minimal understanding of the maintenance and functions of their diesels and systems. These are not more or less carefree like modern cars. They require attention like you are giving it while you still have access to parts, tools and advice. Not nice to have a problem in some open roadstead in the Bahamas or Abacos and have no background or understanding. I learned about this in an unpleasant way myself.


 
 Profile Email  
 
 Post subject: Re: Changing Pencil Zincs W50
PostPosted: 26 May 2018 16:52 
Offline
Skipper

Joined: 24 Sep 2013 09:20
Posts: 393
Hey Ray, I'm almost positive it's opposite of that. The oil cooler has to be cut, and the main heat exchanger does not.

_________________
Zach Duncan
SV Holiday
Hull# 280


 
 Profile Email  
 
 Post subject: Re: Changing Pencil Zincs W50
PostPosted: 26 May 2018 16:58 
Offline
Skipper

Joined: 24 Sep 2013 09:20
Posts: 393
Just checked. Here is one I have precut. The larger one is the oil cooler and the skinnier one is the main raw water exchanger that I don't cut.


Attachments:
20180526_175716.jpg
20180526_175716.jpg [ 1.41 MB | Viewed 0 times ]

_________________
Zach Duncan
SV Holiday
Hull# 280
 
 Profile Email  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 18 Posts ]  Go to page 1, 2  Next

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 7 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Powered by phpBB © 2002, 2006 phpBB Group