46 Chief oil change

[jlammers]

Spent some time on the 46 Chief this week. Filled both oil and fuel tanks with evaporust and let it sit for a few days. I drained the tanks today and flushed the oil tank out with gasoline and used compressed air to dry it completely. I removed the lower plug on the crankcase to drain the oil out and then also removed the upper plug. I filled the oil tank with about 2.5 quarts of oil. Based on what I've researched, the crankcase won't get oil until the bike is started and the oil pump starts circulating the oil? I put both crankcase plugs back in with some thread sealant. What is the purpose of the upper hole in the crankcase, the manual shows it, but doesn't say anything about it? After I run the engine, I assume I'll need to top off the oil tank? One other question, should I pour some oil down the return line to prime the pump or is it OK as-is?
Thanks
Jim

[PaulCDF]

46 Chief oil change


Jim;
My understanding is the upper hole in the crankcase is to drain oil due to STATIC wet sumping a condition where oil "sneaks" passed the plunger when the engine is not running.
So depending on condition of plunger and where it stopped MAY experience static wet sumping. Perhaps others more knowledgeable will weigh in.

[pisten-bully]

...the upper plug, like Paul says, is a sump level plug...so if you have a wet sumping condition you can pull that plug and drain off the excess.

Your oil change procedure sounds okay! We all may do it differently, for instance I drain the sump and also pull the upper plug, then with a syringe (normally used for injecting marinade into your poultry before grilling) I shoot a couple squirts of kerosene into the sump just to make me think I'm cleaning it. Then I install the lower plug and squirt in enough of the motor oil I use through the top plug to fill the sump. I don't prime the supply or return lines to the oil tank unless I've removed them from the pump. That's my story and I'm stickin' with it!

[pisten-bully]

...oh, forgot to ask! Evaporust...is that a good thing to put in your tanks?

[DEEBS47Chief1991]

Evaporust is similar to apple cider vinegar. It will clean rust but should be flushed with water (the gasoline flush you did to the oil tank did the trick). You could even coat over it with light oil like WD40.

Just like the guys stated, the lower hole is for drain and the upper hole is to check return pump level. When my Chief sits for a while I will remove the upper plug and about a cup of oil will come out indicating that the oil moved past the pump bore very slowly over the course of a few months and went down into the sump. This is normal.

You don't want to run the bike with too much oil in the crankcase as it will "Wet Sump". The motor will vibrate more than usual (the flywheels are not supposed to be "dipped" in oil as they will become unbalanced) and you may see some oil seep out of areas such as the cylinder base gaskets. Sometimes even out of the distributor shaft hole. This will eventually clear itself up when the return pump removes the extra oil back into the oil tank but that may take a few minutes and is unnecessarily hard on the motor.



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[DEEBS47Chief1991]

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[jlammers]

I used Evaporust extensively on my COPO restoration, the stuff is awesome as it won't hurt painted portions of the part. The only thing I found out (the hard way) is that Evaporust will remove dichromate coatings if soaked too long. Dichromate coatings were typically used in the auto industry on things like brake booster housings.
I appreciate all the replies, sounds like I'm in good shape with my oil tank

[otis71]

If you don’t prime the lines just be certain to check the tank for oil returning. The chief I used to have never needed it but my friends chief needs it every time it’s sat for a bit.

[Joe G]

If you want to be sure you got all the old oil out, you can put a tube/hose over the return line that comes up through the tank and let it pump into your drain pan. Obviously, you need to keep your eye on the oil level while it is running and top off as needed. It only takes a few minutes before you will start to see the clean fresh oil exiting the pump.

[jlammers]

I did insert a small diameter magnet thru the lower crankcase drain hole to see if it picked up any metal. It came out clean aside from some dirty oil. Since the bike hasn't been run in the last 54 years, once I get it started I'll probably have other things to tend to other than a little bit of old oil in the system. I'll just plan to do another change after some run time.
I have a lot to do yet on this bike like going through the carb and all the electrical, but I'm getting excited to get my foot on that kicker!

[ChiefTwoKicks]

Here's a couple of tips you might want to consider... take notice of the height and location of the vent tube inside of the oil tank. The height of the return tube should be slightly more than an inch from the inside top of the tank, and the vent tube should be about a a half -inch from the inside top of the tank, as well. Be sure the vent is aiming away from the return tube. Don't over fill the oil tank, many guys often check the oil level before you start the bike after its been sitting for a while. If your pump leaks into the sump, it will look like you're low on oil. Adding more oil before you check to see if you have returns, and you may have a added more than the bike needs. It could make a mess.

First, look in the tank... if the level appears low, it MAY mean the pump leaks into the crankcase. Start the bike and let it run for about a minute. If the pump brings the return oil up through the return tube reasonably quickly, the pump is likely in pretty good shape. If the returns take more than 30 seconds or so, the pump is showing signs of weakness or air in the pump, or some other factor (like a crack in the soldered fittings inside, on the fittings), The pulse of the returns should be more than just a spurt-spurt.. if you rev up the motor you could get a facefull of oil !! I would recommend you install a KIWI oil filter, you will have to trim the height of the return tube slightly, allowing for the total height inside the tank. Installed correctly, you will observe the oil bubbling around the filter, and recognize the pump is returning as it should. Be sure the filter is seated all the way down on the return tube. You can slightly bend the tube away from the opening to the tank.

In a perfect world, the returns should be pretty soon, just a few seconds after you get the engine started. If your pump leaks (alot of them do !!), you will have to determine how much is too much.
If you have to prime your pump after only a few days WITHOUT riding your bike, you may have to find out if its the pump, the cracked solder on the return line, the check valve, (ball & seat) on the aluminum pump ('48 & later), or something else. A good oil pump doesn't leak. A weak oil pump is NOT a a good thing. No short cuts here... Your oil pump is the most important part of your engine ( the only other thing that is as important is an intake air leak, right Cotton?)

Sorry for the long winded answer to your oil pump comments. Best of luck, C2K

[PaulCDF]

"I did insert a small diameter magnet thru the lower crankcase drain hole "

Jim; Likely you know Ed Glasgow used to sell magnetized crankcase drain plugs: edsindianbolts.com
as do Kiwi and Geers.

[jlammers]

Pics always help the conversation.....here is a pic of the inside of the RH fuel tank after the evaporust treatment along with pics of the oil tank return tube and vent tube. Given what I know of the history of this bike, the tube height/orientation is how it came out of Springfield.

[DEEBS47Chief1991]

A plunger pump can be rebuilt with new return gears and cover shimming with different thickness gaskets. The plunger can be hard chromed to increase it's size and the bore honed to the exact clearance. Kiwi and some other vendors offer this service.


https://www.youtube.com/watch?v=Zf6X9J3DJuU


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[DEEBS47Chief1991]

https://www.youtube.com/watch?v=Zg2zcvTESwc


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