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I have a 67 mooney m20f the engine was torn down and had a new crank case installed approx 150 hrs ago. At the same time all 4 cylinder had been rebuilt. My oil consumption never really leveled off it seemed to just get worse. Im burning 1 quart every 2.5 hrs. As the plane was just in the shop getting a new jpi 830 the mech notices oil drip from the sniffer valve on the bottom of the sump. We pulled one of the intake tubes and found a pool of oil in the intake. All spark plugs are evenly black and not soaking wet. Egts are all close. Could the vavle guides leak causing oil to run back down the intake tube or could I have a cracked sump that just gives a steady slow leak?

Edited by Spuderman1

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What is a pool of oil?  Dime size, half dollar size, 20,000 gallons, lol.

Seems like higher then normal oil consumption.  You might have someone boreiscope the cylinders  

Check the oil drain back line (3/8 ID) on the cylinder with the oil in the intake.  You can see it on the lower left when looking at the rocker cover just inboard from the cover. If plugged the oil will fill the rocker cover up to and over the valve guilds  

I don’t think I have ever seen a crack oil sump to the intake tubes. 

Jim

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bad break in, bad cylinder rebuild.   There is a drain line for each rocker box.  Pull the rocker covers and see what is going on. 

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Well,

if 1 qt per 10 hours is a typical rough baseline...

1 qt each 2.5 hours is a pretty big amount of oil going missing...

Where is it going? Out the exhaust pipe?

where is it showing up ? On the belly?

is it leaving spots on the ground... a smoke cloud on start-up... anything unusual?

The sniffer valve is a fuel drain for the intake system... not sure how it is connected to an oil leak... oil being in the intake tubes is odd...  sounds like intake valve guides may be leaking?

See Yetti advice below...

PP thoughts only...

Best regards,

-a-

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So the pool of oil in the intake i wish was a dime size but it is about 1/8 inch oil that covers the whole bottom of the intake sump. I keep my oil level at 6 quarts and my belly stays perfectly clean. Next to no oil residue on the belly. I've never noticed a puff of smoke when I start up but I've also never really looked back to take note if it smokes on start up. So if the intake valve guides would leak would it leak enough to actually put that much oil down in the intake? Since I have been using so much oil I figured a jpi 830 would be able to pin point a specific cylinder that could be the issue but so far all cylinders a pretty close egt wise but cyl #1 is alot colder then the rest. My exhaust pipe also isn't dripping in oil it's a nice charcoal black. 

Edited by Spuderman1

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1 hour ago, Spuderman1 said:

So the pool of oil in the intake i wish was a dime size but it is about 1/8 inch oil that covers the whole bottom of the intake sump. I keep my oil level at 6 quarts and my belly stays perfectly clean. Next to no oil residue on the belly. I've never noticed a puff of smoke when I start up but I've also never really looked back to take note if it smokes on start up. So if the intake valve guides would leak would it leak enough to actually put that much oil down in the intake? Since I have been using so much oil I figured a jpi 830 would be able to pin point a specific cylinder that could be the issue but so far all cylinders a pretty close egt wise but cyl #1 is alot colder then the rest. My exhaust pipe also isn't dripping in oil it's a nice charcoal black. 

You didn't mention if you get a pull of oil under the cowl?  I can't imagine you'd lose that much oil on the hangar floor and not notice, though...

The exhaust pipe should just have minimal white/grey residue on the inside, the black suggests you might run too rich.

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32 minutes ago, jaylw314 said:

You didn't mention if you get a pull of oil under the cowl?  I can't imagine you'd lose that much oil on the hangar floor and not notice, though...

The exhaust pipe should just have minimal white/grey residue on the inside, the black suggests you might run too rich.

No pool of oil in the floor either. It's like each cylinder is burning the same amount of oil cause each plug looks similar.

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Spud, don’t forget how valuable pics can be in your problem solving exercise...

Best,

-a-

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Cylinder 1 running around 30-50f cht cooler is normal for my F on jpi930.  Lots more airflow over it.  Also have to know if all the cht probes are same type & location before comparing.

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Where the valve guides are is where the rockers are.  That is drained by gravity by the line on the end of the head.   The gravity drain would have to be plugged to have oil drain down the valve guide.   So check for plugged drain lines and put some orange valve cover gaskets on while you are checking.

Check your bottom spark plugs to see if oil is dripping off them.

If your case was not put back together right, it could just be leaking out of the bottom case halves

Edited by Yetti

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8 hours ago, Yetti said:

Where the valve guides are is where the rockers are.  That is drained by gravity by the line on the end of the head.   The gravity drain would have to be plugged to have oil drain down the valve guide.   So check for plugged drain lines and put some orange valve cover gaskets on while you are checking.

Check your bottom spark plugs to see if oil is dripping off them.

If your case was not put back together right, it could just be leaking out of the bottom case halves

That's where I'm getting stumped the only place I'm finding oil is inside my intake sump. My cowling is nice and oil free from the inside and out, belly is clean, bottom spark plugs are a charcoal black colour but not wet. Attached is some pics from my last flight also the first flight with my new jpi. Second pic is wot and taken after a couple min after take off. First is level cruise setting.IMG_0517.thumb.JPG.33c8dd76f4d8d353cad86efba8c581ed.JPGIMG_0514.thumb.JPG.c9c038bc0b05d7c21c7ac175a4ea0d48.JPG

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Sorry, off the oil leak, but takeoff picture has pretty high cht on 2 & 3... is your mixture set rich enough?  Whats takeoff fuel flow? At 4 C oat, 430 degrees cht seems very high to me.  I usually have no more than about 380 on the hottest cht.

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I have doubts on the cracked sump. Pull the covers, Check the gravity drains for the rocker boxes as Yetti stated.

the picture of the plugs (are they the lowers) do not show oil fouling.

do you have an oil separator installed? 

 

 

 

 

 

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Those plugs don’t look like ones from an oil burner.  Have you pulled the intake tubes to see if they are actually oily inside?  It is possible that the sniffle valve in the bottom of the intake is plugged and you are seeing a build up from some longer period of time?

A little more diagnosis is in order.

Clarence

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15 hours ago, Ragsf15e said:

Sorry, off the oil leak, but takeoff picture has pretty high cht on 2 & 3... is your mixture set rich enough?  Whats takeoff fuel flow? At 4 C oat, 430 degrees cht seems very high to me.  I usually have no more than about 380 on the hottest cht.

I definitely agree with you on the cht's it was my first time seeing the actual reading tag and not just using the original mooney gauge. I'm pretty sure i was still full rich, usually I start leaning a little as I climb through 5000. I know I definitely have some baffle work to do. 

 

8 hours ago, Shiny moose said:

I have doubts on the cracked sump. Pull the covers, Check the gravity drains for the rocker boxes as Yetti stated.

the picture of the plugs (are they the lowers) do not show oil fouling.

do you have an oil separator installed? 

 

 

 

 

 

Yes those are the bottoms. And no I have no oil separator.

 

3 hours ago, M20Doc said:

Those plugs don’t look like ones from an oil burner.  Have you pulled the intake tubes to see if they are actually oily inside?  It is possible that the sniffle valve in the bottom of the intake is plugged and you are seeing a build up from some longer period of time?

A little more diagnosis is in order.

Clarence

I have pulled the intake tube on passenger rear (#3 I believe) and that's when I saw all the oil pooled in the intake, I'll be taking a closer look tonight, I'll fire it up and warm it up and check the valve covers if they are full of oil and I'll take off a intake tube and update with some pics. 

My old gauge would show on takeoff that oil pressure would get up to red line so I always figured that maybe had something to do with it but the jpi shows the pressure isn't so bad. I also thought if the balance guides leaked a bit it would be burning oil so slowly that we aren't really noticing it on the plugs or exhaust. Also my oil gets really black after a 30 min flight back from the mech shop after my swap from min oil to regular oil 

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6 hours ago, Spuderman1 said:

I definitely agree with you on the cht's it was my first time seeing the actual reading tag and not just using the original mooney gauge. I'm pretty sure i was still full rich, usually I start leaning a little as I climb through 5000. I know I definitely have some baffle work to do. 

 

Yes those are the bottoms. And no I have no oil separator.

 

I have pulled the intake tube on passenger rear (#3 I believe) and that's when I saw all the oil pooled in the intake, I'll be taking a closer look tonight, I'll fire it up and warm it up and check the valve covers if they are full of oil and I'll take off a intake tube and update with some pics. 

My old gauge would show on takeoff that oil pressure would get up to red line so I always figured that maybe had something to do with it but the jpi shows the pressure isn't so bad. I also thought if the balance guides leaked a bit it would be burning oil so slowly that we aren't really noticing it on the plugs or exhaust. Also my oil gets really black after a 30 min flight back from the mech shop after my swap from min oil to regular oil 

I have doubts on the cracked sump. Pull the covers, if they are full of oil Check the gravity drains for the rocker boxes as Yetti stated.

the picture of the plugs (are they the lowers) do not show oil fouling.

10 hours ago, M20Doc said:

Those plugs don’t look like ones from an oil burner.  Have you pulled the intake tubes to see if they are actually oily inside?  It is possible that the sniffle valve in the bottom of the intake is plugged and you are seeing a build up from some longer period of time?

A little more diagnosis is in order.

Clarence

I would make sure the sniffle valve is operational. I use rubber tubing and connect to the sniffle drain line and give a little mouth air in (ball moves up and stops airflow)  and out ( ball falls and allows air to move freely ) also making sure the ball is free to move. If sniffle is stuck closed or clogged It is possible  that what you think is oil is fuel and blue fuel dye( dye can become thick and resemble oil). 

I would think Your oil usage is another issue. Something simple to look into 

When you change oil, put in 4 quarts, check what your dipstick reads, do that for 5, 6, 7 and 8 if you use 8 quarts. Make sure your dipstick is showing correctly, wrong dipsticks are not that uncommon. Your mechanic could be putting in 8 quarts (1 for the filter)  but never looking at the dipstick that could be showing 5 quarts but actual 7 in sump,  you add oil, and have high usage cause its back to 5 (really 7)after a few hours. How do I know this happens!!!

 

 

 

 

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19 hours ago, Shiny moose said:

When you change oil, put in 4 quarts, check what your dipstick reads, do that for 5, 6, 7 and 8 if you use 8 quarts. Make sure your dipstick is showing correctly, wrong dipsticks are not that uncommon. Your mechanic could be putting in 8 quarts (1 for the filter)  but never looking at the dipstick that could be showing 5 quarts but actual 7 in sump,  you add oil, and have high usage cause its back to 5 (really 7)after a few hours. How do I know this happens!!!

 

Remember the volume of the oil filter. If you put in x quarts, and read the dipstick, it will read lower after engine start, even with no fuel use/loss.

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13 hours ago, DonMuncy said:

Remember the volume of the oil filter. If you put in x quarts, and read the dipstick, it will read lower after engine start, even with no fuel use/loss.

Yes, I would check dipstick accuracy before a start and If its cold temps give the oil time to settle in. My thought here is that the op recently had an overhaul, did the correct dipstick and or the correct dipstick tube and extensions get installed or others.

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On 10/13/2018 at 7:27 AM, Shiny moose said:

Yes, I would check dipstick accuracy before a start and If its cold temps give the oil time to settle in. My thought here is that the op recently had an overhaul, did the correct dipstick and or the correct dipstick tube and extensions get installed or others.

I've checked the accuracy of the dip stick and it is correct. But even if the dip stick isn't correct it still goes down 4 quarts every 10 hours of flight

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A gallon of oil missing would leave a huge mess... somewhere.

into the cylinders, the lower plugs would be crusty and wet... oil would exit the tail pipe and coat the bottom of the plane....

Blowing out the vent tube would be cleaner on the plugs, but not the belly...

Draining out an oil return line would be pouring out of the cowl.

a crack in the case or a case seal isn’t a magic clean oil eater either...

a prop leak has a nice way of randomly coating the windshield...

Cleaning the engine and searching for leaks is a known procedure...

weak spots in engine case castings are in common known locations... the cracks aren’t common, just the locations when it happens are...

your Cht1 appears to be unrealistic, unless it is in winter OAT for that one cylinder...

Since you have a JPI... and looking for a single point problem...  have you run a gami EGT spread? Is it close? or does one cylinder do something different?

Look up details on how to do that at Saavy.com  Also look up how to send them your data...

If I understand this right...

- a gallon of oil has gone missing 

- oil is pooling in the intake tubes

- Something appearing to be oil is draining out of the sniffle valve.

- oil is dirty in a short period of time.

- this has been occurring since mOH, no change...

 

Want to discuss the break-in procedure that you followed?

What type of cylinders you got, any special coatings...? Like chrome.

Sounds like the break-in didn’t occur... most of the break-in occurs in the first 10 hours... the rest... over the next 90 hours...

Any oil testing done? Any pieces of an oil ring show up in the oil?

have you bought a dental camera yet? One that can see the sides of the cylinders might be interesting...

The dirty oil shouldn’t be happening. That is typical of really worn rings.

oil going missing at that high of a rate in a newish engine shouldn’t be happening.

Hunt down the path of oil into the intake tube... this is really uncommon around here.

Post a pic of the oil in the intake... i’ll Share it with a good mechanic...

Does your mechanic say this is OK to fly? Cause at least one of your friends is waving a caution flag....

Too many unknowns to be comfortable flying for many people...

PP thoughts only, not a mechanic...

Best regards,

-a-

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13 hours ago, carusoam said:

A gallon of oil missing would leave a huge mess... somewhere.

into the cylinders, the lower plugs would be crusty and wet... oil would exit the tail pipe and coat the bottom of the plane....

Blowing out the vent tube would be cleaner on the plugs, but not the belly...

Draining out an oil return line would be pouring out of the cowl.

a crack in the case or a case seal isn’t a magic clean oil eater either...

a prop leak has a nice way of randomly coating the windshield...

Cleaning the engine and searching for leaks is a known procedure...

weak spots in engine case castings are in common known locations... the cracks aren’t common, just the locations when it happens are...

your Cht1 appears to be unrealistic, unless it is in winter OAT for that one cylinder...

Since you have a JPI... and looking for a single point problem...  have you run a gami EGT spread? Is it close? or does one cylinder do something different?

Look up details on how to do that at Saavy.com  Also look up how to send them your data...

If I understand this right...

- a gallon of oil has gone missing 

- oil is pooling in the intake tubes

- Something appearing to be oil is draining out of the sniffle valve.

- oil is dirty in a short period of time.

- this has been occurring since mOH, no change...

 

Want to discuss the break-in procedure that you followed?

What type of cylinders you got, any special coatings...? Like chrome.

Sounds like the break-in didn’t occur... most of the break-in occurs in the first 10 hours... the rest... over the next 90 hours...

Any oil testing done? Any pieces of an oil ring show up in the oil?

have you bought a dental camera yet? One that can see the sides of the cylinders might be interesting...

The dirty oil shouldn’t be happening. That is typical of really worn rings.

oil going missing at that high of a rate in a newish engine shouldn’t be happening.

Hunt down the path of oil into the intake tube... this is really uncommon around here.

Post a pic of the oil in the intake... i’ll Share it with a good mechanic...

Does your mechanic say this is OK to fly? Cause at least one of your friends is waving a caution flag....

Too many unknowns to be comfortable flying for many people...

PP thoughts only, not a mechanic...

Best regards,

-a-

Thanks a lot for the advice! So a little background on the plane I purchased it about 60 hours ago. At 4705hrs. The previous owner at 4612hrs had the engine tore down new crank case, cam, tappet bodies, and bearings, I was told at that time the cylinders had been completely gone through and were pretty much overhauled, honed and new piston rings sets installed, 90 hours later at 4703 cylinder 2 and 4 were removed honed and new rings installed due to oil consumption. 1 hour later at 4704 the prop and hub was overhauled. When it came out of the prop shop is when I purchased it. So the cylinders had about 2 hours of break in time prior. (I'm not sure how they flew it) but when I bought it and continued the breaking I flew mainly wot full rpm for take off and climb then 2500rpm 24-25" cruise. At 4736hrs   The plane had been consuming oil already and I had noticed oil dropping down my firewall and my governor had suddenly only allowed 2600rpm so I swapped out the h1 governor for a new pcu5000. At that same time I had noticed a slight miss at low rpm which turned out to be a right mag problem so it was fixed. I was hoping the oil consumption was the governor leaking but it has not been fixed. 

Im not sure what kind of cylinder the plane has, no oil testing has been done. The first oil change the filter was clean except for one small fleck of metal. I'll try to get a pic of the intake and possibly the inside of the cylinders today. It's amazing how much time a 2.5 year old and a 9 month kids take up. 

Utimately I want a plane that i can be confident in and safe for the family. 

Thanks, Jeff S.

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What oil and did the breaking in have any additives? 

personally, I’d start from scratch with mineral AS100M oil, no additives and run the snot out of it. 

Oil change <10hrs then repete until the oil stabilizes.

Run it at 6qts and note what’s on the belly. 

-Matt

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