Combines Air filter Precleaners

thanks, we have new readers all the time. If one finds some of the plastic pieces warped or melted there are two things to check. As you stated the 'doghouses' or intake screens on combines so equipped can plug thus causing high vacuum and can pull exhaust INTO the precleaner thus melting them. The other is a burnt out venturi inside the exhaust pipe. This will blow out exhaust rather than suck in air. Same results. To check remove the suction tube and place some dry dust or chaft in the palm of your hand and crank engine and run a just over idle. It should suck the light matter out of your hand. The same is true of the precleaner. We have found if the unit is working properly one can disconnect the suction tube, run the engine at above 1800 rpm and take some light corn husks or very light dust and put it into the intake side and the unit will expell the dust or chaff out of the precleaner even without the suction tube attached. Also on the R50-40's where the precleaner sets pointed downward slightly into the intake shield make sure the discharge tube is pointed straight down. Bottom line is as you have pointed out, that even though the op man says nothing about precleaner service it is not a non-service item. The cleaner it is the better it works. Thanks for your reminder and tips.

I would bet your right about the prescreen pluging and suching in the hot exhaust. The flipper you see in some of these systems (when they haven't feel apart) would have prevented burning. I don't remember ever seeing any burning on the '95 or newer machines that have the larger prescreen. In fact I wish they would of just installed larger prescreens and left the rest alone. We found when they added the larger air cleaner asperator assembly they had to many openings going threw. With to many openings the dusty air didn't go threw with enough velocity to spin out dust and also would not hold vacuum where it needed to be. That was an easy fix though. We just siliconed in a few openings as far from sucher pipe as we could. With that we had a very good system, large prescreen, asperator that worked proper, and large air filter. I'm talking machines with V8 Deutz hear. Another thing we did to the V8s is put an extra barb on asperator for as to hook each asperator hose to its own barb instead of the tee. This needs to be done with extreme care as Max points out. The plastic is very flameable and meltable. I have hole carefully cut out so after each little tack weld I spray down with water to keep cool. With a second barb or like some guys do weld on a door you can look along side all the platic deals to see you washed out well. We've had to soak in garbage pail and flush water back and forth for quite some time with pressure washer to get this dirt cleaned out at times. Anything we can do to reduce serviceing to air cleaner the better and safer. Cheers

When attaching precleaner to top of air cleaner body, I run a bead of black silicone at bottom of precleaner where it attaches to air cleaner. Has made a very noticeable difference. No matter how tight and good a fit there seems to be there, the suck inside there will get fine dust in. Especially silicone where the bolt tightens, as it may gap as it tightens there. Usually I can run 4 to 6 days combining between blow out of filter after I did this. I once bought whole new top precleaner from top hood plugging doing soybeans on very still damp night. Been there, done that. We pick up on the go in beans, and have the pickup guy watch it for me. It is a very low cost pre-filter, but not perfect.

Was there ever an issue with the pre-cleaner on my 78 F2IJ It looks to be all metal. Purchased fall 03-new to me.What might I need to do_look for or does this one require no attentionIJ

Our area usually only had the largest of what ever machine was available so no Fs but I'm sure they used the same system as the larger machines. Only thing I remember changing is exhaust pipe location. If you ever get exhaust soot in your air cleaner you would want to look into that. Otherwise you could do as Tim said to see if pipe will such dirt from hand. Tapeing a clear plastic hose onto exhaust pipe nipple and then putting other end into bucket of water is a good way to check vacuum. The precleaner used on them conventional combines had one large spinner as oposed to a bunch of individial spinners. There is a thin groove all the way around where the dirt gets spun into. If that groove has gotten plugged up the precleaner will be usless. Good luck with your machine.

Has anyone tried a spinner type precleaner on these machines. I've often wondered if a Turbo 2 would fit in place of the OEM precleaner. Would certainly do away with chance of sucking exhaust into precleaner.

Syclone pre cleaners from a deere dealer will fix the problem. 6" but not sure which number. you can get a rubber reducer to go from 6" to 10" through donaldson's, around 40-50 dollars. use 6" pvc extended from the air cleaner.

DO NOT use PVC pipe where air is moving thru it at speed! Huge charges of static electricity are built up on the PVC which can cause fire or even explosions in very fine organic dust. ie. dry straw dust. Even far worse if the PVC is insulated by rubber tubes and mountings.