I have a large Ritchie compass that definitely needs fluid added. I suspect it was originally filled with mineral oil, but I am not sure when it was manufactured. West Marine wants to sell me 20 bucks worth of Isophril L, when a couple of bucks worth of mineral oil (which I already have) will do the job . I suspect my compass is over 20 years old. I don't believe alcohol is currently in compass, because the residual film on underneath compass feel light oil in nature. However, I am concerned with compatibility, if current compass fill is not OIL?
And suggestions? I could try mineral oil and if that does not work then I could flush with alcohol and then start over with mineral oil?
First - Ritchie never used mineral oil to fill a compass (except for some old flat top compasses that used alcohol and water). What they did use to fill was mineral spirits. Way different and much more flammable. That's why in 2001 they changed to Isopar L - much less flammable.
Ritchie does sell a repair kit which can save you a significant amount of money depending on the model. I have a Voyager F83W flush mount with combi-dial. The going price for these is still over $100.00 new, while the repair kit runs about $35.00.
Like you, I thought maybe heat had caused the mineral oil to leak out over a long time, so I refilled it with mineral oil. This is how I know they didn't use mineral oil to fill my 1995 era compass! It did not work out well. I did manage to find a new old stock F83W (perfect) for less than $50.00 on ebay to replace it.
BTW, pull your compass and get the model and serial number off the bottom or lower portion. Ritchie's website has a list of manufacture dates by serial number for each model.
