Using primer under mower deck: Which one?

[4310]

Ok I am running out of things to do with the tractor so I thought that I would find out all that I can about primers. I've never used a primer on anything so i don't know what the differences are. I've seen red oxide (i think) on I-beams and recently went to walmart and they had self etching (whatever that means) and a few others. Why use one over the others?

I have a woods 6' rear discharge finish mower (RD7200) that is around 8 years old and starting to show its age. Especially underneath. Last year I finally got a tractor with a loader on it and I can now lift it up to clean it properly. I recently pressure washed it and took a 4 1/2" wire cup wheel to the underside to see what I am working with. The parts that see high friction are clean as a whistle while other parts where the grass has set has become pitted with rust.

I used the wire cup to get off the majority of the flaky rust and then shot it with whatever paint I had setting in a spray can. I'm assuming a primer would make the paint stick at least a little better to the low friction spots but, like I said, I don't know anything about primer.

Right now I'm mainly just concerned with maintaining it so it doesn't get worse. I have read several threads on here ranging from "just spray it out after each mowing", which I intend to do now that I have seen underneath it. Some have said to "sand blast it and use POR-15", which may be a possibilty but I've never used POR-15 or a sandblaster before, nor do I have one. Some have said to "take it apart and have it powder coated". That's probably not going to happen.

At this time I'm mainly just interested in seeing how long paint will stick.

Thanks

 

[Wolfy]

The theory is, primer sticks to bare metal better than paint, but does not hold to the weather like paint. That is why you need both. I've had good luck with Rustoleum, and a few copy cats. POR 15 does not last long once opened, so use it all. It is so expensive, I rarely use it, though a pitted mower deck may be a perfect excuse to use it.

 

[Wolfy]

I don't see the value in spraying out a deck either. Just rusts up bearings. The only thing I clean my decks with is a 1-1/2" putty knife. It is a pain, and I have a lot of decks, but it gets rid of all the wet grass nicely.

 

[ETpilot]

I don't have a problem with grass sticking on my tractor mower deck. I do maintain two Kubota Zero Turn Mowers. These get a lot of sticking grass. So I have started spraying the decks with Pam. This seems to help. The last one I worked on I had very little cleaning to do. As compared to before. I just started doing this so I need to check this further. Anyway FWIW.

 

[hslogger]

My lawn mower decks get hosed down and putty knifed. My five foot rotary mower gets hosed out.
Last summer I had my five foot rotary mower sandblasted and primed, then two coats of epoxy paint. The unit is over thirty years old. I replaced one u joint and the PTO collar, also pulled the swing arm pins out and put new ones in. The machine is like new, again. I wasn't gonna paint the bottom, but the equipment guy said it was a smart move, and worth doing because it will help me keep it cleaner and less rusty for the the next thirty ! Having it painted helps a great deal in preserving it, no doubt.

 

[strum456]

Save your time and money on all of the "paint over rust' type products. They do not work and will eventually exacerbate the problem by peeling back and holding in moisture. If you are not going to sandblast, then it is not worth doing anything.

If you are going to have the deck blasted, epoxy primer is all you need. Epoxy, unlike other primers does not need to be top coated with paint for corrosion protection or abrasion resistance. In fact, it will out perform any paint to my knowledge in these situations. Abrasive blasting and epoxy primer is how I did my 72" Country Clipper Deck. I have mowed many acres with it since I sprayed it with epoxy years ago. I clean the deck once per year, in the fall. The epoxy primer still looks great. I still need to clean it this fall. I will try to get some pictures to share.

 

[PILOON]

One thing you might want to try.
GRAVEL GUARD such as used on car rocker panels, or even pick up BEDLINER paint.

 

[4310]

Actually my first thought before looking into this was to use some sort of bedliner paint but I didn't know if the rough/rubberized paint would collect debris or impede airflow. I may try it before all is said and done though.

What exactly is epoxy primer? Is there a certain kind I should be looking for?

 

[strum456]

Actually my first thought before looking into this was to use some sort of bedliner paint but I didn't know if the rough/rubberized paint would collect debris or impede airflow. I may try it before all is said and done though.

What exactly is epoxy primer? Is there a certain kind I should be looking for?

Bed liner: Don't do it. Any chips down to bare metal will allow moisture will get behind it and stay there causing more harm than good.

Epoxy primer is a 2 part primer (normally a 50/50 mix) used universally for automotive and industrial applications where corrosion protection and adhesion to bare metal is needed. Nearly every manufactured vehicle is dipped in ecoat prior to painting. Ecoat is essentially epoxy primer. Body shops don't typically have the ability to dip parts or vehicles, so they spray epoxy primer onto bare metal before proceeding with other products, like primer/surfacer, filler, or paint. Epoxy primer gives the best possible adhesion and corrosion protection, which is the ideal foundation for a paint job.

All the major paint companies make epoxy primer. PPG, Dupont, BASF, etc.. I use Southern Polyurethanes epoxy primer. They are a smaller company out of Georgia. IMO, they have the best products money can buy, but their prices are reasonable.

 

[GreenWannabe]

When I first got my LX 176, my deck clogged up badly. I had to use the putty knife method, and it still didn't clean it all up. I had to pull the deck and clean it u every time I mowed. The next year, I found out about Fluid Film here on TBN, go my free sample can from them, and sprayed the underside of the deck. What a difference! Every time I mowed, I checked the deck, and no build up! That one application lasted me two years, and then I sprayed it again. I do it every couple of years, and no more problems.

Last fall my tractor and brush cutter were delivered, and one of the first things I did was to spray the underside with Fluid Film. I've cut some pretty tall grass, sometimes pretty wet, and have not had any problem with it building up under the deck.

I can't say enough good things about Fluid film, and keep trying it on all sorts of things I used to use other products for. Note: I have no relationship with the Fluid Film folks, just a very satisfied user.

 

[GreenWannabe]

When I first got my LX 176, my deck clogged up badly. I had to use the putty knife method, and it still didn't clean it all up. I had to pull the deck and clean it u every time I mowed. The next year, I found out about Fluid Film here on TBN, go my free sample can from them, and sprayed the underside of the deck. What a difference! Every time I mowed, I checked the deck, and no build up! That one application lasted me two years, and then I sprayed it again. I do it every couple of years, and no more problems.

Last fall my tractor and brush cutter were delivered, and one of the first things I did was to spray the underside with Fluid Film. I've cut some pretty tall grass, sometimes pretty wet, and have not had any problem with it building up under the deck.

I can't say enough good things about Fluid film, and keep trying it on all sorts of things I used to use other products for. The Fluid Film folks claim it prevents rusting as well. Note: I have no relationship with the Fluid Film folks, just a very satisfied user.

 

[sixdogs]

I've thought about and debated it in my mind for years and came away with the conclusion that paint is the wrong idea. It merely traps moisture and can make things worse. I simply scrape and clean my deck and then spray it with a really penetrating oil like Fluid Film or something like that. Grass may well stick--and it's going to do that anyway--but it's easy to clean the next year and new rust is stopped before it starts.

When I first started this process it was difficult to get all the grass off. I did the best I could, sprayed it with Fluid Film and called it good. The next Spring I had to take the deck off for new blades and discovered the remaining grass was much easier to scrape off because the oil had loosened things up.

Anyway, that's my story. Skip the paint and go with oil.

 

[4310]

Last fall was the first time that I could lift up the mower so I used a garden hose, scraped it, then used fluid film because I read about it on here. I suppose it worked but I don't have anything to compare it to.

I think what I need is a starting point. My plan is to clean it/blast it, use epoxy primer and then periodically continue with the fluid film. I may in fact be wasting my time with the paint but it just seems like the right thing to do. I also plan on spraying it out good with the garden hose every time after I mow. It's not that hard to do since I can lift the whole deck a foot or so off the ground with the pull of a lever.

I would love to sand blast it but have never tried it. Is there a cheap Harbor Freight gun? I've got a 20 gallon compressor and could always use a new tool.

 

[strum456]

Last fall was the first time that I could lift up the mower so I used a garden hose, scraped it, then used fluid film because I read about it on here. I suppose it worked but I don't have anything to compare it to.

I think what I need is a starting point. My plan is to clean it/blast it, use epoxy primer and then periodically continue with the fluid film. I may in fact be wasting my time with the paint but it just seems like the right thing to do. I also plan on spraying it out good with the garden hose every time after I mow. It's not that hard to do since I can lift the whole deck a foot or so off the ground with the pull of a lever.

I would love to sand blast it but have never tried it. Is there a cheap Harbor Freight gun? I've got a 20 gallon compressor and could always use a new tool.

The reason I use epoxy primer on my mower decks is so that I don't have to worry about corrosion. Once epoxy is protecting the metal, I don't see much reason to clean, hose, scrape, etc.. I clean mine once per year for inspection purposes more than anything. Unlike other paints, epoxy is extremely resistant to rust creeping underneath scratches or chips.

With all of that said, you will not be happy if you attempt to blast a mower deck using a 20 gallon compressor and some cheap contraption from HF. Take it to a professional, if there is one in your area. Otherwise, I doubt you will be able to get it clean enough, and you might as well just spray it with oil or something.

 

[4310]

I'll check around. There might be somebody kinda close that has the equipment.

What should I expect to pay for just the underside of a mower deck? And can I just shoot it with the primer immediately or do I have to clean it?

 

[rswyan]

4310,

Leaving aside the question of whether you can get it clean enough, you really don't wanna be blasting without the proper equipment ... which would include a fresh air supply.

 

[sixdogs]

Any tombstone memorial place does sandblasting and most do it for the public for a fee. A mower deck might be too awkward for them but maybe not. The price is pretty cheap and the only way to go. I did 4 heavy 22.5" truck rims on both sides for $100.

Doing it yourself with light duty Chinese stuff will not prove rewarding.

I'll say again the oil will do a better--and by the way cheaper--job than paint that will immediately let moisture underneath. And washing after every use will add more moisture to the equation.

 

[ray66v]

I have used most high end paint products on the market. I can tell you nothing I have seen, will hold up under a mower deck.

Yes, epoxy primers are generally the most durable undercoats.

Many epoxy primers are NOT actually made for direct to metal use. This seems to escape most people who use them, because they do still adhere fairly well, due to their epoxy resin bases.

Unless your primer specifically says it is made for direct to metal use, (that would not include small areas of bare metal "sand throughs"), the procedures guide for that product, will recommend you use an etch of some type, on the bare metal before priming. I prefer vinyl wash primer as an etch, however it's not practical for homeowners. You should at least use a liquid metal prep product for best results.

Since it's pretty much a waste of time, in my opinion, Rustoleum is still the most sensible option for under a mower deck.

 

[5030]

Don't matter, any rattlecan primer/paint. It will be gone in a couple mowings anyway, why throw good money out the discharge chute.....????

 

[Redneck in training]

Google Superhydrophobic coating. That might be the answer. They paint with it lamp posts in Singapore so nothing, such as posters, stick to it.