Coolant leaking John Deere 4320 4520 4720 compact tractor

[oldtimer 66]

Does anybody have a coolant leak on their John Deere 4320, 4520 and or 4720 compact tractor? I have had a leak, some where on my 4320, for about as long as have owned the tractor, which is 9 years. I bought the tractor new in April of 2006. It is the cab model with the 72 inch 7 Iron mowing deck 400X loader and a 3 pt. hitch snow blower. I have approx. 1225 hrs on the tractor and it leaks more than the NSA. The tractor has always been inside in a heated garage, except when I need the room to do a repair. Then it would only set out side during the daytime. The leak is with the aluminum forward end cover. I am going to repair my tractor some time in the early spring before the weather breaks but not now because of the possibility of snow. I have the John Deere maintenance CD. I am just interested on who else may have this problem. I am some what familiar as to what some of the root problems are but I just wanted to get some feed back from other owners that have this same problem. Did you repair it yourself? or did the John Deere dealer repair, How much did it cost etc. At a later date I will post some of my thoughts on this design which are not positive. Thanks in advance.

 

[beenthere]

This was already posted in JD Ag tractors earlier today, I believe.

 

[mechanic327]

This is a very common problem, but not an easy fix. The front cover needs to be removed and resealed. In order to do this, the front axle needs to be removed, because it passes through the oil pan. Also the oil pan needs to be removed because of the pickup tube mounting. It is not a really hard job, just alot of labor involved.

 

[oldtimer 66]

Yes I posted that. I am new to this web site and was not sure as to where to post. Thanks for the reply.

 

[oldtimer 66]

Yes I understand the labor part of the job. The John Deere maintenance CD calls to remove the cab first, and to actually remove the engine to do this repair. I am going to economize on this project and support the tractor directly behind the engine, after removing the drive shaft. Remove the front axle assembly, battery out, leave the engine side rail supports on but loose, remove the oil pan side bolts so as to remove the oil pan, may need to spread rails slightly, remove pick up tube, remove the radiator only leaving the AC and hydraulic oil cooler intact. Then do the cover work, remove alternator, fan, pull damper etc. Hopefully this is a game plan. If anybody else has followed the procedure and it worked let me know. It would be appreciated. Mechanic327 thanks for your reply.

 

[arlen4720]

Yes, I have read a few threads over the years. I think they made a change in 2009, because it always seems to be the older ones. I have also heard that one of the root causes is lack of coolant maintenance.

I had a slight leaking water pump on my 4720, after about 6 months. That was a pretty easy fix, WAAAAAAAAAAAAAAAAAY easier than the front timing cover. It only took the dealer a couple hours to remove and reseal it.

I would probably stick with the factory procedure.

 

[sunnyside360]

I had a new 2007 4320 open station and it started to leak coolant soon after I got it. The leak was around a cover in front of the engine and warranty covered the repair. The JD tech said it was a big job. Never had trouble with it leaking again. Now have a 2010 JD 4320 and it's been trouble free with over 500 hrs on the meter. I believe Deere did some redesign in this area around 2009/2010 (2nd generation 4x20).

 

[oldtimer 66]

FYI on the water pump sealing. I had to reseal the water pump at about 400 hrs, I used the JD sealant which I think is a Hylomar product at about $ 23 for maybe 2 oz. if that. Just enough to do the job. I just re-sealed it again at 1200 hrs. but the sealant the JD dealer had was old. It would not flow in the clear plastic accordion style applicator. So I took it back and purchased some Loctite sealant specifically for anti freeze. Re-sealed the water pump. I was on line maybe 2 weeks after that repair and JD now has a gasket for application and guess what it only costs $3.95. My luck. Part of that is my fault because my maintenance CD still calls for the sealant. Also another note, on some of the instruction to correct this forward end cover leaking problem it is noted that JD now machines the mounting surface on the forward end cover for the water pump mounting. When JD started doing that I do not know. My mounting surface on my forward end cover is a cast surface. Just as a general observation we have a cast iron engine block and a cast iron water pump and JD put and aluminum forward end cover in between. Somebody must of have a mental hernia when they signed off on this design. Anyways, as I have noted in other comments this shows the design was cost driven and not necessarily quality driven. Just my opinion. But thanks for the replies.

 

[wolfpack2]

My 2012 4520 leaked from the water pump with only 50 hours on it. The Factory sealant had failed. The dealer sent out a mechanic who installed a gasket and refilled the coolant under waranty. It only took a couple hours and has been good for the last 2 years and 250 hours.

 

[oldtimer 66]

I am having trouble understanding how this web site works so I may repeat something once in a while./ Anyways wolfpack2 nice tractor and from your reply it appears that the water pump gasket showed up in 2012. That is nice to know. One comment on changing out the water pump, yes it is any easy repair/ reseal and or add gasket. There is only one bolt that is somewhat shrouded by the fan pulley. I think a flat ratchet takes care of that problem other wise everything else is straight forward. Now back to the forward end cover. I may have already mention this but the engine leak kit comes with gasket that seals the FEC to the cylinder block. My tractor is a 2006 model and it did not have a gasket either at the water pump and or at the FEC mounting to the cylinder block. My engine was sealed with sealant only in these areas. Now this FEC gasket appears to be laser cut from approx. .020 steel/ SS and the sealant is molded in and or NC applied. I will know more when I purchase the kit. This gasket has probably taken care of this portion of the FEC leaks but there is still the " L shaped " gasket and " him " that seals the cylinder head to the FEC. I will send this much and follow up with another reply.