Oil leaking out exhaust manifold

Work Horse

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B7200 HST 4x4
Jan 21, 2020
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Like the title says, oil is coming out the exhaust manifold, and it's leaking out where the stack bolts to the manifold. My first thought was valve seals... Any thoughts?

It does not appear hydro oil, coolant, or diesel is mixing with the engine oil. Is it safe to run for a few hours this weekend, so long as I watch the engine oil level? TIA
 

SDT

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Apr 15, 2018
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SE, IN
Like the title says, oil is coming out the exhaust manifold, and it's leaking out where the stack bolts to the manifold. My first thought was valve seals... Any thoughts?

It does not appear hydro oil, coolant, or diesel is mixing with the engine oil. Is it safe to run for a few hours this weekend, so long as I watch the engine oil level? TIA
Sounds like wet stacking.

Have you been puttering around?

SDT
 

Work Horse

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Equipment
B7200 HST 4x4
Jan 21, 2020
108
1
18
IPSWICH
Sounds like wet stacking.

Have you been puttering around?

SDT
Ahh, never even thought of that. Something I've heard of many times - but never seen the direct results of. Yes, at the time I noticed the leak she was at low idle. I was installing farm gates and using the loader to lift/swing the gates as I installed them. I'm assuming if it's just wet stacking I could resolve the issue with a high idle speed, correct?

Tractor didn't smoke excessively after I went to move some hay/shavings around afterwards. Just "under load," which is normal.
 

Dave_eng

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M7040, Nuffield 465
Oct 6, 2012
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Williamstown Ontario Canada
Ahh, never even thought of that. Something I've heard of many times - but never seen the direct results of. Yes, at the time I noticed the leak she was at low idle. I was installing farm gates and using the loader to lift/swing the gates as I installed them. I'm assuming if it's just wet stacking I could resolve the issue with a high idle speed, correct?

Tractor didn't smoke excessively after I went to move some hay/shavings around afterwards. Just "under load," which is normal.
It is not engine speed but engine load that will fix diesel slobber aka wet stacking.

Plowing, driving a pto generator with a heavy electrical load, pulling a heavy trailer in hilly terrain.

The heavy load causes high cylinder pressures which help maintain piston rings to cylinder seal.

Dave
 

Work Horse

Member

Equipment
B7200 HST 4x4
Jan 21, 2020
108
1
18
IPSWICH
It is not engine speed but engine load that will fix diesel slobber aka wet stacking.

Plowing, driving a pto generator with a heavy electrical load, pulling a heavy trailer in hilly terrain.

The heavy load causes high cylinder pressures which help maintain piston rings to cylinder seal.

Dave
I will have to shut the tractor off more when I'm low idling for extended periods. Generally the tractor is getting worked pretty good. So is the load on a tractor engine much different from a diesel pickup/semi truck? I ask because a lot of guys with trucks say to high idle when sitting for extended periods to prevent wet stacking. I think what your saying is a higher idle may "help," but it doesn't have the same effect as engine load does. Do I got that right?

This is the first I have noticed any wet stacking, what are the chances there could already be engine damage?
 

Dave_eng

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Lifetime Member

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M7040, Nuffield 465
Oct 6, 2012
4,002
363
83
Williamstown Ontario Canada
I will have to shut the tractor off more when I'm low idling for extended periods. Generally the tractor is getting worked pretty good. So is the load on a tractor engine much different from a diesel pickup/semi truck? I ask because a lot of guys with trucks say to high idle when sitting for extended periods to prevent wet stacking. I think what your saying is a higher idle may "help," but it doesn't have the same effect as engine load does. Do I got that right?

This is the first I have noticed any wet stacking, what are the chances there could already be engine damage?
You have understood my point about load vs rpm.

You don't want to jump to a diagnosis.

If you have not changed how you used your tractor over many years and then this oil issue appears, then wet stacking is not likely the cause.

Check the crankcase vent ( I think they still exist on a B7200). Make certain the tube is not obstructed in any way. Open end tubes attract flies and wasps which build with mud.

I don't think you can compare modern diesel truck engines with complicated emissions to your tractor in terms of determining how to deal with idle situations.

Your initial question had to do with continued use while you figure out what bis happening. I do not see a problem doing so.

Removing the exhaust manifold may give you a much better idea if one cylinder or all three cylinders are contributing to the oil.

There is a crankcase vent filter that you access from inside the valve cover.

forum B7200 crankcase vent filter.jpg


Dave
 

Work Horse

Member

Equipment
B7200 HST 4x4
Jan 21, 2020
108
1
18
IPSWICH
You have understood my point about load vs rpm.

You don't want to jump to a diagnosis.

If you have not changed how you used your tractor over many years and then this oil issue appears, then wet stacking is not likely the cause.

Check the crankcase vent ( I think they still exist on a B7200). Make certain the tube is not obstructed in any way. Open end tubes attract flies and wasps which build with mud.

I don't think you can compare modern diesel truck engines with complicated emissions to your tractor in terms of determining how to deal with idle situations.

Your initial question had to do with continued use while you figure out what bis happening. I do not see a problem doing so.

Removing the exhaust manifold may give you a much better idea if one cylinder or all three cylinders are contributing to the oil.

There is a crankcase vent filter that you access from inside the valve cover.

View attachment 61323

Dave
Thank you Dave,

Sorry for the delayed response. The 7200 was due for an oil change soon so I went ahead and did that last night, and cleaned up the oil. I will know later today if it will continue to leak or not. The crankcase vent is still functional, it had always had a steady "puff" of smoke coming from it, and it still does.

If it continues to leak, which I think it will - I will start digging into it further.

Thanks again