Unusually clean Perkins

[Gulfstar 36]

As I have been getting to know my new to me boat I noticed the lack of sludge and crud under the oil fill caps on my 2 Perkins 4.236 engines. I have had diesels before and I currently have 2 oil cars and I know that they can get dirty. These are vintage 1975s with a reported 3500 hours on them. I have put about 35 more hours on them since changing the oil this spring and it still looks amber. Do these really run that clean? Do you think someone had the covers off and cleaned up in there?

 

[chiropaul]

I have the same engine with only 1500 hrs on it in Tortuga. The oil remains amber, too. I had 6.354's in my last boat and that oil always turned black almost immediately. Those engines only had 2200 hrs. on them.

 

[skipperdude]

How is the oil removed from the oil pan?

It is usually the sludge in the bottom of the pan that turns the oil black. It is from incomplete removal of all the old oil.

On my engine the old oil is removed from a hose and a ball valve on the bottom of the oil pan as you would a car.
Sometimes the dipstick tube oil removal doesn't get it all out.

SD

 

[Gulfstar 36]

Not sure how the PO did it but I use the dipstick method.

How is the oil removed from the oil pan?

It is usually the sludge in the bottom of the pan that turns the oil black. It is from incomplete removal of all the old oil.

On my engine the old oil is removed from a hose and a ball valve on the bottom of the oil pan as you would a car.
Sometimes the dipstick tube oil removal doesn't get it all out.

SD

 

[chiropaul]

Yes, I will add that like Skipperdude, the oil in my engine is removed from the pan via a hose on the bottom of the pan and gets all the oil from the engine. However, this was also the setup on my 6.354's but due to the angle of the engine, not all of the old oil was removed. Seems on that engine installation the drain plugs were at the front of the pan as opposed to the rear.

 

[Third-Reef]

My 25 year old Volvo TMD41As with 1600 hours on them are clean like that inside. Their oil while not amber is cleaner than the oil in my ford truck 7.3L diesel ever was, even 10 min running after the oil change. I think some marine engines run cleaner becasue they run a constant even load at the proper temperature. Road diesels see quite a varrying load and produce a good bit of soot because of it.

 

[Marin]

Do these really run that clean?

That photo looks pretty much like what I see on our two 1973 FL120s, a bit under 3,000 hours each. But the oil that comes out of the sump when I change it is black. We run Delo 400 30wt and change it every 100-150 hours.

 

[Edelweiss]

As I have been getting to know my new to me boat I noticed the lack of sludge and crud under the oil fill caps on my 2 Perkins 4.236 engines. I have had diesels before and I currently have 2 oil cars and I know that they can get dirty. These are vintage 1975s with a reported 3500 hours on them. I have put about 35 more hours on them since changing the oil this spring and it still looks amber. Do these really run that clean? Do you think someone had the covers off and cleaned up in there?

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Yes, I pull the valve covers every spring and check the valve lash on my 1976 twin 6.354's and they are clean just like that. My oil turns black usually after 3 or 4 hours of running at speed. Looks bad but the Perkins people said that is carbon from combustion of the fuel and normal for the engine.
Larry B