Gunk/Varnish Build Up On Engine Oil Plug

   / Gunk/Varnish Build Up On Engine Oil Plug #1  

Woodstock Walt

Silver Member
Joined
Jan 12, 2022
Messages
161
Location
Bryant Pond, Maine
Tractor
Mahindra 5155 4WD
Hi, all.

2019 Mahindra 4540 with 230 hrs.

I changed the engine oil at 50 hrs. and refilled with Mahindra 15w-40 upon my dealer's recommendation.

Today at 230 hrs. I drained the oil and replaced with Chevron/DELO 5w-40 synthetic to help with cold starts. It's what I should've used when I serviced it at 50 hrs.

Anyways, when I wiped off the drain plugs I noticed what looked like a buildup of sludge around the plug and crush washer.

0Yxq7f9.jpg



After removing the sludge with a pick I found it was hard, brittle, and varnish-like.

0xpjjZS.jpg



I reinstalled the cleaned plugs and refilled with the 5w-40 syn, tractor runs great and seems noticeably smoother and quieter at idle. Is that buildup of varnish on the drain plugs something I should be concerned about? What would cause that? Should I be worried about varnish buildup in other parts of the engine?

This occurred using dealer-recommended Mahindra engine oil with 180 hrs. of service life.

I'd appreciate any thoughts or opinions you might have. Thank you!
 
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   / Gunk/Varnish Build Up On Engine Oil Plug #2  
if you still have the drain oil and it was put into a clean bucket, you could send it out for analysis.
 
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   / Gunk/Varnish Build Up On Engine Oil Plug
  • Thread Starter
#3  
if you still have the drain oil and it was put into a clean bucket, you could send it out for analysis.

I actually saved a quart of it for that reason, I'm just not sure what the best option is for having it analyzed. I am familiar with the concept, I've just never personally sent oil out to be analyzed. Is there a specific lab or company you'd recommend?
 
   / Gunk/Varnish Build Up On Engine Oil Plug #4  
I actually saved a quart of it for that reason, I'm just not sure what the best option is for having it analyzed. I am familiar with the concept, I've just never personally sent oil out to be analyzed. Is there a specific lab or company you'd recommend?

Blackstone. I use them whenever I can.

 
   / Gunk/Varnish Build Up On Engine Oil Plug #5  
It looks like a thread sealer applied by OEMs to ensure no leaks from the factory. The sealer will also serve as a anti-galling agent as it is assembled when dry and will ensure the plug will come out later. Some sealers are put on as a liquid at the manufacturer and others are put on the plug threads at the plug manufacturer and are dry at the time of install. This looks like the liquid type.

Amazon.com
 
   / Gunk/Varnish Build Up On Engine Oil Plug #6  
Also, copper plug sealing washers are normally a one-time use as the copper actually gets hardened when compressed. Same with aluminum ones, so, have spares.
 
   / Gunk/Varnish Build Up On Engine Oil Plug #7  
Could be, but he probably would have wiped all that off or noticed it on first oil change at 50 hours.
Anything is possible.….
Oil analysis is the only way to eliminate guessing
 
   / Gunk/Varnish Build Up On Engine Oil Plug #8  
Concerning the copper crush washers, .......I've never replaced one with a new washer yet. Even though I've read about the need for it, I've always used the OE on trucks, cars, and Kubotas. and never had a leak....... yet.
Cheers,
Mike
 
   / Gunk/Varnish Build Up On Engine Oil Plug #9  
Anneal the copper washer with a torch and reuse it. I have done that with copper head gaskets on my motorcycle engine for years with no issues. Some factories recommend it. As for engine oil, I never use the factory recommended house brand oil. I have no idea who makes the Mahindra oil. Using a brand name like Delo, Rotella or Delvac (my choice) is the best insurance for quality oils. Even the Wal-Mart brand Supertech is a VG oil. It is made by Warren Petroleum, a large, trusted refiner and blender.

Don't forget the oil filter. House brands may be fine to get you past the warranty. I use Wix filters whenever possible. They are often less costly than the house brand. Thay are owned by the Germans and are known for quality.

As mentioned, Blackstone is a good source for oil analysis. They will provide comments with the analysis. Also, you may want to call them and ask about your drain plug debris.

Keep us posted as to the outcome.
 
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   / Gunk/Varnish Build Up On Engine Oil Plug #10  
Anneal the copper washer with a torch and reuse it. I have done that with copper head gaskets on my motorcycle engine for years with no issues. Some factories recommend it. As for engine oil, I never use the factory recommended house brand oil. I have no idea who makes the Mahindra oil. Using a brand name like Delo, Rotella or Delvac (my choice) is the best insurance for quality oils. Even the Wal-Mart brand Supertech is a VG oil. It is made by Warren Petroleum, a large, trusted refiner and blender.

Don't forget the oil filter. House brands may be fine to get you past the warranty. I use Wix filters whenever possible. They are often less costly than the house brand. Thay are owned by the Germans and are known for quality.

As mentioned, Blackstone is a good source for oil analysis. They will provide comments with the analysis. Also, you may want to call them and ask about your drain plug debris.

Keep us posted as to the outcome.
Interesting comment about the WalMart oil…
Never knew Warren Petroleum made it!
LSNE (learn something new everyday)
Thanks
 
 
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