Lesson Learned

Maybe I needed to learn this lesson earlier. Next winter I will try running diesel through my machines before putting them up for the winter. My first year I used Mineral Spirits...no problem...next 3 attempts resulted in re-packing pumps. I have read many testimonials about using diesel but I was worried about getting it all flushed properly. Now I would rather flush diesel than pay for re-packing after winter. By the way, anyone else in the Northern areas tired of crappy weather? Can't wait for consistent sunshine!

We have used mineral spirits for years to store our machines during the winter months. So far, no problems. I can't imagine what could cause you to repack a pump if it was left with mineral spirits and there was fresh throat oil on top of the packings.

I agree with Randy. Something else must be going on. For over twenty years that is what we winterize with and never had a problem in spring. I have backup sprayers that I have not used in years and 4 yrs later start up three pulls and no problems. Diesel will work,but I believe you have some other issues going on . More info.

We winterized in October....Didn't get them out again until March. This year my 3400 was just fine but my 3500 was "dry". Then when priming it started leaking fluid out the pump. Last year the 3500 was O.K. and the 3400 was "dry"...then leaked while priming. When I put them away I thoroughly clean them with Toulene and then flush with mineral spirits...then I prime them with fresh mineral spirits and put them away for Winter. At first I thought maybe I wasn't flushing enough and the Toulene was drying them out...but last year I definately spent enough time and mineral spirits to make sure it was ALL flushed out. I asked my local pump repair guy and he said the leather packings do better when stored with a 3 part diesel to one part 30 weight oil. According to what he told me the mineral spirits are drying out the leather packings and they split leaking out the mineral spirits which causes everything to dry out completely...meaning I re-pack the pump. I am definately not an expert on the subject and am only repeating what he told me. I certainly would like to find a method to make sure I am not wasting time and money my first week back to work.

we don't have a need to "winterize" here We work year round! I have stored using mineral spirits, I usually cap off and disconnect hoses to keep from losing fluids...

I use pump armour. Its cheap and I have NEVER had a problem.

I feel the issue you are having is evaporation related. Sometimes you have to go in the "overkill" mode by flushing as you did, relieve all system pressure, make sure the prime valve and guns are shut off, and seal the suction tube with a plastic bag and tape shut. Also make sure all fittings are tight especially the suction hose. I like using mineral spirits, but as you have heard, I too have heard of "home brewed" mixes of Diesel, diesel and solvent, Hydraulic oil, Hydraulic oil and solvent. Bottom line you have to keep the leathers immersed in solvent to keep them moist, otherwise leather will dry out. With your over the Winter success rate to date I would probably add something to the mineral spirits as suggested less prone to flashing off. It would be interesting to leave an inch of mineral spirits in a small cup with the machine next Winter and see how long it lasts.

Around here we don't have to deal with freezing so leave primary machines loaded on paint all year. However for pumps being stored I simply do a really good flush, load onto diesel and forget. I find diesel best as it's cheap as chips and I don't need to bother to clean it out before using the pump, simply purge onto paint, recirculate it for a minute and start working... If you're a waterborne type of person perhaps antifreeze could be the ticket, Cormac would know better than I how the packings might feel about it though.

You don't have to use Mineral Spirits for everything, just fill the pump through the recirculation line with diesel, it is better for the packings. Mineral Spirits is fine for the lines & guns. WD-40 is best for the pump but diesel is much cheaper and about as good. It's all about the "oil" being good for the leathers as your pump fellow told you. (Note: this for long-term in the "hard winter" states, short term Mineral Spirits is fine, and of course if you work year-round the paint can stay in)

Diesel can gel and/ or freeze. Mineral spirits is safer.

I am still saying mineral spirits. I have only been striping 9 yrs,but have run a commicial painting biz 16,and where I am at it gets cold to say the least. Minus 34 a couple of mornings ,and my diesel trucks sleep in on those days,if you get my drift. To each his own. I wish I could put a answer to our problems, but I have 14 spray rigs and mineral spirits in all winter no problems.

SJO wrote on Mar 20, 2009:Go to #10

Diesel can gel and/ or freeze. Mineral spirits is safer.

Not quite, diesel has a wax-like substance that can coagulate when cold enough and clog fuel filters etc. As soon as it warms it's fine. Diesel will not "freeze". But that why diesel trucks that run in winter have fuel heaters (as does your Powerstroke Ford) or they use fuel additives that prevent the waxy substance from gelling. Using it in a machine won't cause problems, you are just going to recirculate it out with mineral spirits and it will have warmed above about 27 probably so no problems. But if you want the best it's a light oil like WD-40, that just gets expensive (especially since I used big-bore Spee-Flos) and of course this only applied too "leather" the oild doesn't dry it but keeps it expanded and "sealed". Of course this person's problem could have been it was time to replace the packings anyway; nobody has mentioned that...

Don, The way it was explained to me on the pump I had rebuilt is like this: The diesel soaks into the leather seals, when it gels(diesel state of freezing) it expands which pulls apart at the leather. When it thaws the leather has been weakened and therefore gives out much more quickly. Sometimes right away, sometimes a couple weeks into the season. For us in the north where 27 may be a warm day and sub-zero spells are common, the $4-$5 extra to use mineral spirits is a safer and MUCH cheaper option.