420 hyd pump won't prime when cold
420 hyd pump won't prime when cold
Over the years I have had an issue where the hydraulics will sometimes not work in cold temps, it has been happening more and more often and now drives me nuts.
Last year I replaced the hydraulic oil using ISO 32 (specified by owner's manual) because there were ice crystals in the oil from the accumulated water, it worked great and I thought that had been the problem.
Now it is doing it again, the pump won't pick up the oil for whatever reason. Last time I needed to use it I heated the oil and took the suction line off the pump and poured gear oil in to prime it and then it took off.
Yesterday I needed it again, no hydraulics, took the line off and poured some in the pump, still nothing, but I also did not heat the oil. The great blizzard of 2015 turned out to be 2" of snow, so I quit messing with it.
Is the pump worn out or what? The hydraulics seem strong enough and there is no oil getting into the engine. It worked fine all summer.
Last year I replaced the hydraulic oil using ISO 32 (specified by owner's manual) because there were ice crystals in the oil from the accumulated water, it worked great and I thought that had been the problem.
Now it is doing it again, the pump won't pick up the oil for whatever reason. Last time I needed to use it I heated the oil and took the suction line off the pump and poured gear oil in to prime it and then it took off.
Yesterday I needed it again, no hydraulics, took the line off and poured some in the pump, still nothing, but I also did not heat the oil. The great blizzard of 2015 turned out to be 2" of snow, so I quit messing with it.
Is the pump worn out or what? The hydraulics seem strong enough and there is no oil getting into the engine. It worked fine all summer.
- DukeofDeere
- 1010 crawler
- Posts: 443
- Joined: Wed Oct 26, 2011 7:12 am
- Location: Hudsonville Michigan
I suspect it is ice in a line. This happened with my 1010. Although I checked the tank several times for water, it had little in the tank. Turned out it would collect in a hose that drooped a few inches across the back of the crawler. Every time it went into freezing temps it would freeze up. I eventually took one end of the hose off (on a warm day) and poured the water out, then changed all the oil. Problem solved for me.
Scott
Scott
450`s c-dozer 6 way, b-loader.
350`s c-loader + ripper, b-loader with winch arch. B-loader with dozer pads
backhoe attachment.
1010 loader with forks for round bales
a few 610 Bobcats. many attachments
350`s c-loader + ripper, b-loader with winch arch. B-loader with dozer pads
backhoe attachment.
1010 loader with forks for round bales
a few 610 Bobcats. many attachments
On a 420 the intake for the pump is a line up from the tank and past the engine and down to the pump. Both this line and the pressure line back to the valve body are dry. I don't know if it's normal for these to bleed down after sitting.
The oil is new last year, and any water is supposed to emulsify in the oil, and last time I had the hydraulics working I started it a few days later to check it (very cold outside) and it worked again, so it's not ice.
Had to use a cable come-along on the blade to push snow a couple times. I try to do this when the neighbors aren't watching.
The oil is new last year, and any water is supposed to emulsify in the oil, and last time I had the hydraulics working I started it a few days later to check it (very cold outside) and it worked again, so it's not ice.
Had to use a cable come-along on the blade to push snow a couple times. I try to do this when the neighbors aren't watching.
Usually a small crack in the suction line, of the rubber compression ring doohickey at the pump is old and not sealing well.
Even when the crawler is shut off, there should be a column of oil still on top of the hyd pump that does not leak out, so if you also have a leak on the top of the pump by the suction line, definitely the compression piece.
Lavoy
Even when the crawler is shut off, there should be a column of oil still on top of the hyd pump that does not leak out, so if you also have a leak on the top of the pump by the suction line, definitely the compression piece.
Lavoy
Parts and restoration for antique and late model John Deere crawlers.
Owner and moderator www.jdcrawlers.com
Owner and moderator www.jdcrawlers.com
OK, I feel like an ass... Turns out it was ice after all.
For some reason the oil looked clean and unfrozen when I looked down the hole the dipstick goes in. But I pulled out the intake pipe to inspect it, and in that hole it was full of milkshake and the pipe was plugged solid with ice. After heating the pipe a little I extracted a 4 1/2" long plug.
Even though the oil was new last year it apparently filled up pretty quick with water from heavy rain washing past the seal around the valve body return to the tank. Time to replace that and quit leaving it out in the storms.
For some reason the oil looked clean and unfrozen when I looked down the hole the dipstick goes in. But I pulled out the intake pipe to inspect it, and in that hole it was full of milkshake and the pipe was plugged solid with ice. After heating the pipe a little I extracted a 4 1/2" long plug.
Even though the oil was new last year it apparently filled up pretty quick with water from heavy rain washing past the seal around the valve body return to the tank. Time to replace that and quit leaving it out in the storms.
- Stan Disbrow
- 350 crawler
- Posts: 2904
- Joined: Fri Jul 15, 2005 3:13 pm
- Location: Raleigh, NC
Hi,
Things that make one go 'Hmmmm'. Oil floats on water.....
Glad it was something so simple (and inexpensive)!
Stan
Things that make one go 'Hmmmm'. Oil floats on water.....
Glad it was something so simple (and inexpensive)!
Stan
There's No Such Thing As A Cheap Crawler!
Useta Have: '58 JD 420c 5-roller w/62 inside blade
Useta Have: '78 JD350C w/6310 outside blade
Useta Have: '68 JD350, '51 Terratrac GT-25
Have: 1950 M, 2005 x495, 2008 5103 (now known as 5045D)
Useta Have: '58 JD 420c 5-roller w/62 inside blade
Useta Have: '78 JD350C w/6310 outside blade
Useta Have: '68 JD350, '51 Terratrac GT-25
Have: 1950 M, 2005 x495, 2008 5103 (now known as 5045D)
- DukeofDeere
- 1010 crawler
- Posts: 443
- Joined: Wed Oct 26, 2011 7:12 am
- Location: Hudsonville Michigan
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