Another Perkins Question

[Deborah Ann]

Our first trawler. 1978 Thompson Trawler made by Thompson Offshore Company in Titisville, Fl. Single Perkins 4-154 engine pumping out a blistering 65HP. Great first trawler but I am having an issue with the last oil change. Stated capacity of oil system is 10QTS. But after sucking the oil I only get 4+ Qts. I see all the plugs on the oil cooler, should I be pulling these to drain all the oil from the system? The Perkins "books" are quite vague.
Thanks,
Gerry

 

[Nomad Willy]

Deborah,
Most engines don’t fully drain.
I just replace what’s in the crankcase and let the rest mix. You’ll replace that next time.
But on most systems replacing the filter will take care of most of the oil.

Your “first” trawler is bigger than ours (30’ and 37hp) and our Willard is the last trawler ... unless we down-size. And that’s not likely. You’re wrong to think of the Thompson as water wings. Got a picture?

 

[STB]

I'd have bet on the capacity of those being closer to 9qts, plus whatever is in the oil cooler and loop. So, maybe 10 qts in all. Depending on which size filter you run, there can be up to about a quart in there.

That engine usually has a very v-shaped pan. Trying to get to anywhere near the bottom of it through the dip stick can be tough.

There is usually a drain plug on the center line of the front or back of the /pan/ that gives you more of an ability to go straight to the bottom and manipulate the hose more freely, whereas going through the dipstick constrains your ability to steer an normally leads to the hose deflecting so it doesn't go all the way in.

You don't want to remove any of the other plus. Depending upon which one you are looking at, it might be a freeze plug and not intended for frequent use.

Also, you want to run the engines for 10-15 minutes before doing an oil change. The idea is to let it get hot enough to thin out and to stir the sludge at the bottom, where you may not be able to get to it, back into the oil that you can get to, so it doesn't build up. Some people like to wait a very few minutes for the oil to settle back into the pan before pumping out, but I don't do this figuring it'll happen as I am setting up and pumping.

In any case, you don't want to run it long enough that it gets too hot to deal with. The risk of the oil being too hot is to the human doing the oik change, the plastic hoses being used, etc. Other than that, more run time thins thenoik, mixes in the dirt so it can get sucked out, etc.

At any rate, maybe going at it warm and from the plug vs dip stick, poking around a bit to find bottom, and counting the oil in the filter will get you closer.

 

[Lepke]

4 quarts out of 10 isn't a good oil change. There isn't a lot of oil that doesn't drain to the pan. Usually just the hoses, cooler, and what's in the filter. Make sure your suction tube is in the pan bottom. As I remember, the only way to drain the oil from the cooler is to disconnect the hoses. The plugs are for draining the water or zincs. Some people put in a tee with a drain valve, but the cooler and hoses are probably less than a quart.
If you can get to the pan drain, you can have a hose made at a hydraulic supply that attaches where the plug drain is. Put a valve on the free end and a fitting that will match your drain tube. Have the hose long enough so it's easy to connect to your oil drain pump. That way you get all the oil.

 

[Deborah Ann]

Couple of recent pictures. Thanks for the help.

 

[FF]

"Also, you want to run the engines for 10-15 minutes before doing an oil change. The idea is to let it get hot enough to thin out and to stir the sludge at the bottom"

Although a short warm up is way better than nothing , I would prefer a 3 or 4 hour run under load.

All of todays oil has detergent in it , but if you want the gunk stick to the engine insides it takes both heat and time to dissolve the stuck stuff , that was fine enough to pass thru the oil filter.

 

[Pete Meisinger]

There are different types and systems for "sucking out the oil". If you used a hand pump through the dipstick tube you will never get all the oil, especially cold.

You really need to find the engine oil pan drain, put a hose attachment on it and use an electric vacuum pump to get it all. You are doing yourself and your engine a dis service by trying to suck oil out through the dipstick tube.

pete