For those refilling a compass...

Black Valkyrie

Active Member
Jul 19, 2014
688
Canada
Boat Info
1993 Sundancer 270 DA
Engines
Twin 4.3
02635043_L.jpg
 
Fluid worked. Diaphragm is toast so will have to order a new one. No idea how to upload pix here so cant post them. Open the filler screw and pump more in. Used one of those ear squirters for cleaning our kids ears.
 
Something about filling a sealed container completely with kerosene and letting it sit out in the sun bothers me...

So I looked it up -
The flashpoint of Isopar L is >62*C (144*F)
The flashpoint of kerosene is 37 to 65*C (100 - 150*F)

But -
I would think that since there is not supposed to be any air inside the compass dome, flashpoint would not really be a concern, rather the auto-ignition temperature would be the concern.
Auto-ignition temperature of Isopar L is 335*C (635*F)
Auto-ignition temperature of kerosene is 220*C (428*F)

I wonder how hot a compass housing can get sitting out in the direct sun. Is it possible for the fluid to act as a magnifying glass and create a pinpoint of heat on the compass card or similar part?

Just some random thoughts on the matter.
 
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You are supposed to use Isopar L or mineral oil.

I tried mineral oil which didn't work so good. It seemed to dampen the movement of the card way too much. I'd stick with the Isopar L.
 
I tried mineral oil which didn't work so good. It seemed to dampen the movement of the card way too much. I'd stick with the Isopar L.

You are probably right. I refilled a compass once with mineral oil (added to existing oil) but it was not much that I had to add. More of a top up. So I did not notice a change. But it is more viscous than compass fluid is. I have actually heard of people using kerosene before, but did not think it was a good idea then. If the compass leaks, you are basically allowing a flammable liquid to leak down inside your dash down among your instruments. It might leak into the cabin too (depending on the boat layout) and that smell will be there for a long time.
 
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You are supposed to use Isopar L or mineral oil.

No... you're supposed to use Isopar L or paraffin based Odorless Mineral Spirits - NOT mineral oil! Very different chemicals with very different viscosities. This is clearly explained on the Ritchie website. What I posted is exactly that. Paraffin based odorless mineral spirits.
 
Received my replacement parts from ritchie... new diaphragm, dome gasket and filler screw gasket. Unit refilled and back on the boat... good as new! And again- NO - contrary to the poster above DO NOT use mineral oil! Very clearly states this on the Ritchie website!
 
Just buy a new compass. Their not that expensive.

While they may not be that expensive, it can be difficult to find an exact replacement. I purchased a new compass with the exact same number as the old one, but it used four mounting screws instead of three, so I had to buy a 90* drill attachment to drill four new holes. By the time you figure in purchase price, extra tools, and having to go through a new alignment procedure, buying brand new isn't necessarily such a good deal.

Edit: And I just remembered that I even had to enlarge the hole for the body of the new compass as well.
 
While they may not be that expensive, it can be difficult to find an exact replacement. I purchased a new compass with the exact same number as the old one, but it used four mounting screws instead of three, so I had to buy a 90* drill attachment to drill four new holes. By the time you figure in purchase price, extra tools, and having to go through a new alignment procedure, buying brand new isn't necessarily such a good deal.

Edit: And I just remembered that I even had to enlarge the hole for the body of the new compass as well.
The fluid ran out of my compass so I ordered the parts from Ritchie to fix it. I thought I was good to go. A month later the fluid level starting getting low again.So I ordered a new compass and haven’t a problem since. Should have done that to begin with. Two weekends ago I was out on Lake Superior late at night. A storm came up and although I have gps I sure was thankful for my compass.
 
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The fluid ran out of my compass so I ordered the parts from Ritchie to fix it. I thought I was good to go. A month later the fluid level starting getting low again.So I ordered a new compass and haven’t a problem since. Should have done that to begin with. Two weekends ago I was out on Lake Superior late at night. A storm came up and although I have gps I sure was thankful for my compass.

There you go. Everybody has a different experience. My compass repair was an epic fail, too - hence the new compass. Of course, Being a river boater I really didn't need a new compass, or even a working one. Just my CDO that says "everything must work correctly".
 
Just buy a new compass. Their not that expensive.


Well, my particular model is $450 so $12 in gaskets and $4 in fluid is more than worth it. Not sure how any of this could "fail" when repairing it. All you are doing is replacing gaskets. Anyways.... mine is great now... at the same time installed an articulating arm to hold my Nexus 9.
 
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After reading a bit more, I now realize that Ritchie and other manufacturers do not recommend mineral oil for compasses, so I will delete my earlier post. That was an alternative in the past, but not anymore.

It is true that finding a good replacement for older compasses that are in molded “wells” on helms is not always easy. I had that issue with a past boat to replace an old danforth that had yellowed and had to make up a starboard plate to fit the well and install in the plate. Looked OK and saved fibreglass modifications.
 
Received my replacement parts from ritchie... new diaphragm, dome gasket and filler screw gasket. Unit refilled and back on the boat... good as new! And again- NO - contrary to the poster above DO NOT use mineral oil! Very clearly states this on the Ritchie website!
Can you share where you purchased the parts from? I'm needing to refill mine and am not finding the gaskets.

Thanks,
Kevin
 
Can you share where you purchased the parts from? I'm needing to refill mine and am not finding the gaskets.

Thanks,
Kevin


From the manufacturer. I just called them directly. They took my serial number, looked up the gaskets required and put them in USPS to me. Had them in 4 days.
 

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