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Prop Sludge, High Oil Sample Numbers & Reusable Oil Filter

mfleming

mfleming

Well Known Member
Patron
Yesterday I picked up my resealed Hartzell constant speed prop from the prop shop. 100 hours from new and it had to be resealed due to slinging grease.
When I removed the prop it was shocking to see the grey greasy oil in the prop hub and crank. The prop shop said the hub was packed with a grey clay like substance. This somehow caused the prop to start slinging grease. I need to figure out what's going on before I reinstall the prop.

My suspicion is the reusable S15 oil filter MAY be the culprit. Why? Well the first 25 hours of the engines life (I0-360-M1B) the factory Champion oil filter was in service. Then I installed the S15 reusable filter, 25 hours later, changed the mineral oil out for Phillips XC 20W50 and Camguard. The sample results that came back from Blackstone were stellar. The next oil change happened at 50 hours (100 hours total time) and the sample results were concerning. Some of the results risen significantly. At this time the prop was removed for resealing and the ugly grey oil was noticed in the crank and prop hub.

QUESTION:
  • Any thoughts on the grey sludge and what produces it?
  • Besides cleaning out the visible area of the crank, is there anything I should do to ensure the grey stuff isn't in the governor?
  • Could this have been caused by not getting all the Lycoming preservation oil out before the initial engine run?
I have a call into Lycoming but will have to wait until Monday.
My tentative plan is to remove the S15 filter and install a Champion filter, run for 25 hours then change the oil and pull the prop for inspection.
 
CAMGUARD can’t recall the post, it was recent weeks. Vic Syracuse commented about Camguard during breaking in new engine PM/Conversation him. I‘ll keep looking for the recent post. Pretty confident the S15 not an issue.
 
Can’t find post I wanted, did find reference to Camguard the company doesn’t recommend using until after break in. I think Vic was waiting until 100 hrs to use.
 
Grey sludge sounds like what happens when leaded fuel is run with a synthetic oil, at least from what I've read - no personal experience. What kind of oil were you using? Any additives? What items in the Blackstone report showed bad numbers? Typically if something is bad, they make a comment about what it is, and what could be causing it.
 
Might have some kind of contamination or incompatibility in your oil and/or additives.
I would pull a valve cover and see if there is any grey gunk there. Maybe oil cooler lines, same.
If you don’t get any plausible smoking gun or solid answers:
I wouldn’t wait 25 hours. I would consider a complete oil/filter change, no additives, and check in a few hours.
There is an A/D on hollow crank engines running fixed pitch props. When I did this on the Buckers 0320 I was surprised how little gunk there was there. Maybe not a fair comparison. I don’t honestly know how much oil is recycling or actually flowing in a CS system. I bet somebody here knows. Might give a clue.
 
BH1166 said:
CAMGUARD can’t recall the post, it was recent weeks. Vic Syracuse commented about Camguard during breaking in new engine PM/Conversation him. I‘ll keep looking for the recent post. Pretty confident the S15 not an issue.
Click to expand...
The Phillips XC 15W50 with Camguard went in at 50hrs. The engine appeared to be fully broken in at that time but maybe not.
rv8ch said:
Grey sludge sounds like what happens when leaded fuel is run with a synthetic oil, at least from what I've read - no personal experience. What kind of oil were you using? Any additives? What items in the Blackstone report showed bad numbers? Typically if something is bad, they make a comment about what it is, and what could be causing it.
Click to expand...
I attached the Blackstone report, which contains the first sample at the end of the mineral oil break-in and then the current sample with the higher numbers.
Back in the day, I ran Aeroshell 15W50 semi synthetic in a O-470 and it was super clean when broken down for overhaul at 1700 hrs, 1450 hrs with semi synthetic.
JonJay said:
Might have some kind of contamination or incompatibility in your oil and/or additives.
I would pull a valve cover and see if there is any grey gunk there. Maybe oil cooler lines, same.
If you don’t get any plausible smoking gun or solid answers:
I wouldn’t wait 25 hours. I would consider a complete oil/filter change, no additives, and check in a few hours.
There is an A/D on hollow crank engines running fixed pitch props. When I did this on the Buckers 0320 I was surprised how little gunk there was there. Maybe not a fair comparison. I don’t honestly know how much oil is recycling or actually flowing in a CS system. I bet somebody here knows. Might give a clue.
Click to expand...
There's clean oil in there now that hasn't been run...just waiting to get the condition inspection completed. Pulling a valve cover is a good idea...

6RM_oil_report.jpg
 
I always thought silicon numbers being high was a sign of dirt/dust getting in the engine. Are you operating in dusty conditions? Are you sure your air filter is tight? The silicone numbers have been high since new by the looks of it.
 
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mfleming said:
The Phillips XC 15W50 with Camguard went in at 50hrs. The engine appeared to be fully broken in at that time but maybe not.

I attached the Blackstone report, which contains the first sample at the end of the mineral oil break-in and then the current sample with the higher numbers.
Back in the day, I ran Aeroshell 15W50 semi synthetic in a O-470 and it was super clean when broken down for overhaul at 1700 hrs, 1450 hrs with semi synthetic.

There's clean oil in there now that hasn't been run...just waiting to get the condition inspection completed. Pulling a valve cover is a good idea...

View attachment 60076
Click to expand...
It sure looks like a lead problem to me! But why so much lead in the oil? Leakage by the rings????
 
Sludge buildup inside the crank shaft bore is pretty common.
Years ago when an AD Jon mentioned was issued on Lycoming crank shafts, the first thing that had to be done was scrape all of the crud out of the inner crank shaft bore so it could be cleaned and then inspected. I had a a tool specially made for doing this.
The bore necks down in diameter at the first rod journal so on all of the cranks I ever inspected, there was always some sludge trapped in the larger diam. area fwd of that.
Not sure why the prop shop would say the prop was full of sludge though.
 
Jetmart said:
I always thought silicone numbers being high was a sign of dirt/dust getting in the engine. Are you operating in dusty conditions? Are you sure your air filter is tight? The silicone numbers have been high since new by the looks of it.
Click to expand...
It is. If you mean Silicon (Dioxide). Thats not the same as Silicone.
 
Jetmart said:
I always thought silicone numbers being high was a sign of dirt/dust getting in the engine. Are you operating in dusty conditions? Are you sure your air filter is tight? The silicone numbers have been high since new by the looks of it.
Click to expand...
I'm not operating in dusty condition but I have flown through a lot of smoke from wild fires. I just cleaned the intake filter but how it fits is definitely something I'll check out further.
 
Just some thoughts:
If you still have some samples of the grayish goop - sent to Blackstone & Phillips & Camguard & Hartzell for their analysis.
Camguard is not recommended for break-ins due to reduced friction which is NOT what break-ins want - that said it should not cause any weird chemical reaction as you have experienced. From your description, I think you waited till engine broken in for the most part.
All original preservatives will have disappeared with 1st oil change - should not be an issue.
? - Was Hartzell prop new, not sitting for 10 years before use... or was it a field OH that possibly had some non-standrd grease in it (I suspect unlikely).
Presumably, when prop installed - you didn't pack the crank snout with any grease... just lubed the O-ring with engine oil & installed.
and lastly - Prop governor was most likely brand new, with just assembly oil oozing from ports.
That's pretty much it.
 
Same thoughts as AZSteve053 -- if you saved some of the sludge, send it to Blackstone for analysis.

From your last analysis --
Silicon -=> dust in the air
Lead -=> Possible leakage of fuel from the pump into the case -- watch this one...
Calcium/Phosphorus -=> Camguard, Detergent in Oil

...and oh by the way - No oil filter is capable of filtering out elemental compounds that are measured in the nM - pM scale... Think of a cyclone fence stopping a BB...
 
AZSteve053 said:
Just some thoughts:
If you still have some samples of the grayish goop - sent to Blackstone & Phillips & Camguard & Hartzell for their analysis.
Camguard is not recommended for break-ins due to reduced friction which is NOT what break-ins want - that said it should not cause any weird chemical reaction as you have experienced. From your description, I think you waited till engine broken in for the most part.
All original preservatives will have disappeared with 1st oil change - should not be an issue.
? - Was Hartzell prop new, not sitting for 10 years before use... or was it a field OH that possibly had some non-standrd grease in it (I suspect unlikely).
Presumably, when prop installed - you didn't pack the crank snout with any grease... just lubed the O-ring with engine oil & installed.
and lastly - Prop governor was most likely brand new, with just assembly oil oozing from ports.
That's pretty much it.
Click to expand...
Not enough gray stuff left for analysis I'm afraid. My main concern is, the prop shop said the grease slinging was due to the grey stuff. I can't be getting a prop reseal every 100 hrs!

I'm not 100% bought into the theory about the grey stuff causing the grease slinging.. The grease was clean grease and the grey stuff was not in contact with the grease side of the hub.

The prop was brand new but had been stored in my heated garage for about 2 years before installing it. Hartzel told me that I had ABOUT 2 years in storage before the grease seals would retain a set and start slinging grease. So that may be the real cause !?
 
IMO, the grey stuff didn't cause the grease slinging. Engine oil doesn't make it to the blade side of the prop. The grease slinging is/was probably because the Aeroshell your prop was greased with from the factory (prior to a certain date) separated into clay sludge and thinner oil. The oil slung out and the clay (a thickener added to oil to create grease) stayed put.

The grey sludge is a byproduct of leaded fuel. I found a ton of it in my O-320 when I rebuilt it 20+ years ago.

Unrelated issues, IMO.
 
bjdecker said:
See attached -- if there is a failure of the fuel pump internal diaphragm and/or other parts it will dump fuel into the accy case.

View attachment 60077
Click to expand...
It would need to fail two diaphragms to put fuel in the crankcase, plus it would typically show fuel from the telltale port.
bjdecker said:
...and oh by the way - No oil filter is capable of filtering out elemental compounds that are measured in the nM - pM scale... Think of a cyclone fence stopping a BB...
Click to expand...

Some of them won't even stop 40 micron trash.
 
Kyle Boatright said:
IMO, the grey stuff didn't cause the grease slinging. Engine oil doesn't make it to the blade side of the prop. The grease slinging is/was probably because the Aeroshell your prop was greased with from the factory (prior to a certain date) separated into clay sludge and thinner oil. The oil slung out and the clay (a thickener added to oil to create grease) stayed put.

The grey sludge is a byproduct of leaded fuel. I found a ton of it in my O-320 when I rebuilt it 20+ years ago.

Unrelated issues, IMO.
Click to expand...
Grease separation seems to be an issue across multiple manufacturers. I was told MT a few years ago started using a grease that was produced in Germany that performed much better. A 5-gallon bucket of grease I looked at last year at a prop rebuilder had pockets of oil laying on top of the grease below it. The prop rebuilder now was using the new MT grease is what I was told and performed better?? Mine slung grease after being in the paint shop static for 4 months a few years ago. (Covid delay) My guess is as others have speculated the engine oil issue and slinging grease are not related.
 
mfleming said:
Yesterday I picked up my resealed Hartzell constant speed prop from the prop shop. 100 hours from new and it had to be resealed due to slinging grease.
When I removed the prop it was shocking to see the grey greasy oil in the prop hub and crank. The prop shop said the hub was packed with a grey clay like substance. This somehow caused the prop to start slinging grease. I need to figure out what's going on before I reinstall the prop.

My suspicion is the reusable S15 oil filter MAY be the culprit. Why? Well the first 25 hours of the engines life (I0-360-M1B) the factory Champion oil filter was in service. Then I installed the S15 reusable filter, 25 hours later, changed the mineral oil out for Phillips XC 20W50 and Camguard. The sample results that came back from Blackstone were stellar. The next oil change happened at 50 hours (100 hours total time) and the sample results were concerning. Some of the results risen significantly. At this time the prop was removed for resealing and the ugly grey oil was noticed in the crank and prop hub.

QUESTION:
  • Any thoughts on the grey sludge and what produces it?
  • Besides cleaning out the visible area of the crank, is there anything I should do to ensure the grey stuff isn't in the governor?
  • Could this have been caused by not getting all the Lycoming preservation oil out before the initial engine run?
I have a call into Lycoming but will have to wait until Monday.
My tentative plan is to remove the S15 filter and install a Champion filter, run for 25 hours then change the oil and pull the prop for inspection.
Click to expand...
In the eighties Hartzell came out with a " roll and peen'' AD on the blade shanks; so a lot of props had to come off immediately and then periodically there after. Be cause of this I have removed many Hartzell props, all of them had gray paste on the inside bore of the crankshaft , and also a small amount in the prop hub, inside receiving bore.

The inside of the hollow crankshaft acts as a centrifuge and deposits lead sludge against the interior of the hollow crank bore, little of this deposit can get back out because the tube that delivers oil to the interior of the crank places it dead center in the bore. The paste can not climb back out.
 
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BoydBirchler said:
In the eighties Hartzell came out with a " roll and peen'' AD on the blade shanks; so a lot of props had to come off immediately and then periodically there after. Be cause of this I have removed many Hartzell props, all of them had gray paste on the inside bore of the crankshaft , and also a small amount in the prop hub, inside receiving bore.

The inside of the hollow crankshaft acts as a centrifuge and deposits lead sludge against the interior of the hollow crank bore, little of this deposit can get back out because the tube that delivers oil to the interior of the crank places it dead center in the bore. The paste can not climb back out.
Click to expand...
i saw the grey crankcase sludge in early in the life of my Whirlwind prop. I presume the lead originates from fuel, but how does that get into the crankshaft? i had a lot of it maybe 10 years ago when I pulled the prop for an inspection and reseal, but interestingly, I subsequently had several hundred hours of trouble free operation, and when I just recently pulled the prop again, there was very little sludge.
 
erich weaver said:
i saw the grey crankcase sludge in early in the life of my Whirlwind prop. I presume the lead originates from fuel, but how does that get into the crankshaft? i had a lot of it maybe 10 years ago when I pulled the prop for an inspection and reseal, but interestingly, I subsequently had several hundred hours of trouble free operation, and when I just recently pulled the prop again, there was very little sludge.
Click to expand...
The fuel burns in the cylinder (with lead) but some of the combustion gases escape past the piston rings into the crankcase. The lead is suspended in the oil and circulates in the oil system, depositing out in the centrifuge effect of the crankshaft at the prop flange.
 
mfleming said:
Yesterday I picked up my resealed Hartzell constant speed prop from the prop shop. 100 hours from new and it had to be resealed due to slinging grease.
When I removed the prop it was shocking to see the grey greasy oil in the prop hub and crank. The prop shop said the hub was packed with a grey clay like substance. This somehow caused the prop to start slinging grease. I need to figure out what's going on before I reinstall the prop.

My suspicion is the reusable S15 oil filter MAY be the culprit. Why? Well the first 25 hours of the engines life (I0-360-M1B) the factory Champion oil filter was in service. Then I installed the S15 reusable filter, 25 hours later, changed the mineral oil out for Phillips XC 20W50 and Camguard. The sample results that came back from Blackstone were stellar. The next oil change happened at 50 hours (100 hours total time) and the sample results were concerning. Some of the results risen significantly. At this time the prop was removed for resealing and the ugly grey oil was noticed in the crank and prop hub.

QUESTION:
  • Any thoughts on the grey sludge and what produces it?
  • Besides cleaning out the visible area of the crank, is there anything I should do to ensure the grey stuff isn't in the governor?
  • Could this have been caused by not getting all the Lycoming preservation oil out before the initial engine run?
I have a call into Lycoming but will have to wait until Monday.
My tentative plan is to remove the S15 filter and install a Champion filter, run for 25 hours then change the oil and pull the prop for inspection.
Click to expand...
I tore down my engine core to find lots of gray taffy sludge in the inner bore of my crank, I took my time and cleaned it out with a soft wooden spoon being careful of the cross oil tube in the center of the bore. The crank went in to AS was cleaned, coated.I guess the best part of the lead deposits, I had No pitting. I find synthetics to run thinner then there rating(IMHO) I'm an older flat tappet, not roller as new engines over the last 15 years or so. Cam guard is a must have in these older engines. Synthetic or not 50hours is too long between oil&filter changes. Please do not forget to pull the sump screen and check & clean that also. IMHO
 
erich weaver said:
i saw the grey crankcase sludge in early in the life of my Whirlwind prop. I presume the lead originates from fuel, but how does that get into the crankshaft? i had a lot of it maybe 10 years ago when I pulled the prop for an inspection and reseal, but interestingly, I subsequently had several hundred hours of trouble free operation, and when I just recently pulled the prop again, there was very little sludge
Click to expand...
 
The cylinder gets a small amount of oil splashed or sprayed in on the underside of the piston, during each cycle; this along with blow by gets some TEL in the oil.
 
This morning I talked to Hartzel technical support. The said the grey clay in the prop hub was most likely from the grease settling out during its 2 year storage.
I’m thinking the grey sludge in the crankshaft was a red herring. There was very little in the hollow crank on further inspection.

Today I’ll clean out what little oil and sludge is in the crank and hang the prop…

PS. Hartzel said that after greasing or a prop reseal, it might sling grease for up to 10 hrs :oops:
 
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