The viton type needle in carb can stick if not run in a while. The 400 fuel pump can't overcome it. The carb is easy to clean and reassemble. Kits are from JD at about $14. I keep 3 on the shelf. Aftermkt kits are $67. Some people wack the carb while pump's ticking w/ a screwdriver handle, etc. I don't. Your choice.David
Arrow's '75 JD400 "restoration" thread
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That’s oddly specific... 🤔
Good to know! So in that case, it would appear that it is getting fuel from the tank then because I had it running for several minutes. The last time when I brought it into the garage, I was actually able to get it to idle for a while with the throttle all the way down and the choke off. For the better part of a year, I haven't been able to get it to do that! It would only start up and run with the choke & throttle in a very specific (& slightly variable) position. I don't know if that is connected with a sticky needle valve or not, but I'm sure that could be a factor. I'm guessing that the carb generally needs a good cleaning and soaking in some carb cleaner. I have a gallon (or quart?) of the stuff with a basket used to sail parts in. I will look into ordering a few carb rebuild kits to have on-hand.
That being said, I'm still contemplating buying a replacement carb from iSaveTractors for $70 because the previous owner told me about how this engine ingested 3 (out of 4) of the bolts that hold the bottom of the air filter housing to the carb. Apparently the bolts loosened and went all the way into the combustion chambers where the likely got caught and caused the engine to stop running. I'm guessing that the bolts didn't make it past the valves. The PO extracted the bolts and then used locktite on the one remaining bolt. It seems like the threads for the others are stripped or nearly stripped. I'm unsure if the PO had to remove the head in order to recover the bolts as that detail wasn't addressed and I didn't think to ask at the time. I'm guessing that those bolts could have done a nice little number on the valve seats. Less likely to do too much to the carb. Until just now, I thought replacing the carb would resolve the aforementioned stripped threads, but I just realized that there is a 90 degree elbow bolted to the front of the carb where the air box housing bolts to... So it looks like I need to source THAT piece too. Perhaps it's identical to the part in the original K532 that I have sitting in my shed (snapped a rod back in the 80's).
'75 JD 400 workhorse
And upon further inspection, that front left rim is solidly the worst of the 4. I hope that I can get it cleaned up, but there's a real chance that it might be toast or at least that is have to replace it before I put a FEL on there because if I have to thin it out too much, I may not trust it to hold the extra weight.
'75 JD 400 workhorse
'75 JD 400 workhorse
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*Carb rebuild kit
John Deere Carburetor Kit AM100019 - Green Farm Parts
Find John Deere Carburetor Kit AM100019 here. Shop for John Deere Carburetor Kit AM100019 and 400000 genuine John Deere parts online at Green Farm Parts.
greenfarmparts.com
(Just to prevent any possible confusion)
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Arrow, are those new v61 tires taller then the stock fronts?
I’m not trying to hijack Arrows thread, however, since we are discussing the 400 carbs I have a question.
My 400 “hunts” or ”surges” a little when at idle. If I crack the throttle off idle it smooths out. What would be the cause? Governor adjustment or something else?
Thank you.
I’m not trying to hijack Arrows thread, however, since we are discussing the 400 carbs I have a question.
My 400 “hunts” or ”surges” a little when at idle. If I crack the throttle off idle it smooths out. What would be the cause? Governor adjustment or something else?
Thank you.
Sounds a bit lean on idle circuit which could cause governor to push open throttle a bit. The carb would then get some fuel from main circuit adding RPM for a moment. Speed would drop back to lean idle. the cycle repeats. Have you tried opening the idle mixture volume adjustment a bit? Dirt in carb or vacuum leak in induction somewhere also can be masked by opening the idle mix volume screw. An intake air leak is most troublesome at idle. David
Well I have the K582 in my tractor so the rebuild kit for the K532 carb probably won't work. Anyone know the part number for the rebuild kit from JD?
I also checked the K532 engine I have sitting with a broken rod and found that the carb is gone. Makes me begin to wonder if the carb from the K532 was used on the K582 when it was installed. However the engine swap was done by JD at a dealership as I have documentation from the dealership... Hmm...
'75 JD 400 workhorse
I also checked the K532 engine I have sitting with a broken rod and found that the carb is gone. Makes me begin to wonder if the carb from the K532 was used on the K582 when it was installed. However the engine swap was done by JD at a dealership as I have documentation from the dealership... Hmm...
'75 JD 400 workhorse
It looks like that in the picture. However, the V61s are the same spec as the turfs that are on it. But that front tire in particular is low on air, so it's squatting, the front turfs are also nearly bald on the inside of the tires - seems like there's some camber or toe-in issues that I might need to look into further at some point.
It's also possible that the V61s are slightly taller. I also found that the front turfs are also only 2 ply tires... The V61s I got are the 6 ply versions - ready for a FEL one of these days!
'75 JD 400 workhorse
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No I have not tried the mixture screw, but now I will.
Thanks for that information.
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Arrow,
The carb kit that David listed will work on all the K series Kohler carbs (K241 thru K582 and KT's). With regard to the four stripped screw holes in the air horn, is it possible to re-tap them using the next larger screw?
Harold
The carb kit that David listed will work on all the K series Kohler carbs (K241 thru K582 and KT's). With regard to the four stripped screw holes in the air horn, is it possible to re-tap them using the next larger screw?
Harold
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A trick that I have found useful for getting the low and high speed settings close on my K582 is to defeat the idle speed specification of 1600 to 1700 by adjusting the dashpot (wire installed) to get the idle to 700-800 or what sounds like a nice idle. The 1600 to 1700 just seems really high to my ear but there are good reasons for it to be that high. Once the lower idle is in play, adjust the low speed to best running-and maybe just a touch on the rich side. Then turn the dashpot down back to the spec idle speed. Set the high speed at about 3-1/2 to 4 turns out. The only time I can get the high speed really dialed in is moving snow and getting the Kohler to really grunt-followed by some trial and error.
Adjusting the low speed this way keeps the carb in the low speed circuit. At spec idle the carb is right at the point of running on the high speed circuit and adjusting the low speed at high idle isn't very satisfying. These K532-582's need to run pretty rich to stay cooler. They will burn a bit more gas but gas is cheap (last week, anyway). They need all the help they can get to run on the cool side.
Adjusting the low speed this way keeps the carb in the low speed circuit. At spec idle the carb is right at the point of running on the high speed circuit and adjusting the low speed at high idle isn't very satisfying. These K532-582's need to run pretty rich to stay cooler. They will burn a bit more gas but gas is cheap (last week, anyway). They need all the help they can get to run on the cool side.
Good to know! I will go ahead and get a couple to have on-hand.
On the topic of the air horn (is that what it's called?) bolts. Yes, I likely can tap them the next size up. I'd first need to find the right bolts to use as I will either need washers or cap bolts because the metal for the air cleaner housing is cracked and the holes are more open than they are supposed to be.
'75 JD 400 workhorse
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"Dashpot" might be a kind of old school term for the "anti-dieseling" solenoid mounted just forward of the carb. The running idle adjustment is made with the engine running and the solenoid engaged. There is a stop nut on the underside against the solenoid mounting bracket that is loosened to allow the whole solenoid to screw in/out of the bracket to set the idle speed.
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