JD 730D Black Oil in Exhaust

Johnb730D

Member
On my 730 diesel, I had a problem with the injection pump leaking fuel into the crankcase so I had it rebuilt. Since reinstalling it, I've had an issue with the tractor blowing oil out of the exhaust. It doesn't appear to be engine oil because I just changed oil and it's very clean. The oil coming out of the exhaust is very black and sooty. It starts to blow out oil after a few minutes of running and it mainly leaks out between the exhaust pipe and the muffler. I took the pipe and muffler off and saw that the inside of the exhaust manifold is covered with oil.

Since reinstalling the pump, I've also noticed that the tractor is always blowing out blue smoke which I'm guessing is due to the excess oil sitting in the exhaust manifold and pipe. The tractor seems to blow out more black oil and blue smoke when running the engine faster and putting it under heavier loads. Does the injection pump need to be timed to the engine? If so, what is the procedure? Lastly, I had the injectors tested and one of them was rebuilt with a new valve. I reinstalled the injectors and the tractor continues to blow oil and smoke out of the exhaust. Any help on this issue would be greatly appreciated.
 
I'd start with checking the timing on both pumps, I'm surprised it was not reset as the service book shows already. That may be all it needs, unless the pumps are not balanced correctly. Last 720 injectors and pump set I serviced the pumps were not flowing even at all when first checked on the test bench. Owner said he thought junior had been messing with it..
 

I don't have a repair manual for this tractor yet. Could someone explain how to do this or scan and post the pages in the manual where it tells how to set the pump timing?
 
Typical 730 Diesel. They slobber when you don't work them often. Put a plow on it and go work it for a day. Should clear it right up. Don't be surprised if it starts smoking real bad for a bit, just keep pulling and it will clear up.
I had that happed with mine, and the first trip down the field on half mile rows I thought I screwed up the engine. Black smoke and oil flying out of the exhaust. Kept it up for almost another 1/4 mile, then cleared up and ran perfectly. Just take it out and work it. They weren't make for light duty work.
 
Hope this helps.
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I finally read the manual for my Perkins AD3 where it says to NOT warm it up just loping along, but rev it up to 1200 rpm for 3 minutes. Don't operate it just idling along, but work it at 1700 rpm. I now do that, and all slobbering / fuel dripping / smoking has stopped.
 
When you get everything right you will still have slobber.
Your muffler and pipe are soaked so it will take a while
for it to get cleared out. You might remove them and run
a solvent through them. Be sure it dries before reinstalling.
Run tractor at high rpm.
 
Thanks everyone for the responses. Will working the tractor get rid of the oil slobbering for good or will it start doing it again when just idling around? We've had this tractor since 1960 and it has never once spit out oil like this. You could let it idle all day and it wouldn't slobber. How would a rebuilt pump cause this slobbering? Could it all be in the timing? I will say that in reinstalling the pump I had to force it down to get the bolts started. Not sure if that is normal. Also, when I had the injector return lines off, I noticed there are orings that seal that lines in the head. I couldn't find these in the parts book. How are these orings supposed to stay in place?
 
Thanks everyone for the responses. Will working the tractor get rid of the oil slobbering for good or will it start doing it again when just idling around? We've had this tractor since 1960 and it has never once spit out oil like this. You could let it idle all day and it wouldn't slobber. How would a rebuilt pump cause this slobbering? Could it all be in the timing? I will say that in reinstalling the pump I had to force it down to get the bolts started. Not sure if that is normal. Also, when I had the injector return lines off, I noticed there are orings that seal that lines in the head. I couldn't find these in the parts book. How are these orings supposed to stay in place?
 
I do not get any slobbering out of my 70 d. I haven't pulled any thing like a plow since I rebuilt the engine years ago. It mostly idles all day.
 

Possibly the thinned out fuel diluted engine oil washed years of caked on carbon from around the rings and ring lands ? Now the the lube oil can pass by?
Could try a heavier straight weight oil and a 195F stat in addition to a work out.
 
I used the 730 to plow 80 acres and the slobbering problem went away after about an hour of plowing. However the problem came back after driving it down the road (in sixth gear) a few miles. Before I started using it, I checked the timing of each pump and it was correct. A few diesel mechanics have told me that the cylinder walls could be getting a glazed buildup which will allow more engine oil past the rings and also cause unburned diesel fuel to spit out of the exhaust pipe. Does anyone agree with this?
 

It would cost many thousands of $$$ to go through the engine. May want to consider just puting up with it, as any diesel wants to wet stalk when operated slow, cold and lightly loaded.
Engine oil viscosity and coolant temperature ?
 
(quoted from post at 15:05:36 11/28/16)
It would cost many thousands of $$$ to go through the engine. May want to consider just puting up with it, as any diesel wants to wet stalk when operated slow, cold and lightly loaded.
Engine oil viscosity and coolant temperature ?

b&d
black exhaust slobbering is commonly refereed to a "wet stacking" not "stalking" :wink:
 
(quoted from post at 16:49:50 11/28/16)
(quoted from post at 15:05:36 11/28/16)
It would cost many thousands of $$$ to go through the engine. May want to consider just puting up with it, as any diesel wants to wet stalk when operated slow, cold and lightly loaded.
Engine oil viscosity and coolant temperature ?

b&d
black exhaust slobbering is commonly refereed to a "wet stacking" not "stalking" :wink:

Tiny little smart phone, two thumbs and auto correct are a dangerous combination.
 
(quoted from post at 12:05:36 11/28/16)
It would cost many thousands of $$$ to go through the engine. May want to consider just puting up with it, as any diesel wants to wet stalk when operated slow, cold and lightly loaded.
Engine oil viscosity and coolant temperature ?

I run Rotella 15w-40 and the coolant temp stays in the 170-180 range.
 
(quoted from post at 22:37:44 11/28/16)

b&d
black exhaust slobbering is commonly refereed to a "wet stacking" not "stalking" :wink:

Tiny little smart phone, two thumbs and auto correct are a dangerous combination.[/quote]

I agree the auto correct function on smart phone does get annoying at times. :oops:
 

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