Author Topic: First oil change  (Read 4028 times)

johnny williams

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First oil change
« on: January 02, 2006, 11:40:30 PM »
I have a GM90 6/1 with 20hrs > or < on it and changed the oil for the first time today. The engine has been run from waaaaay too fast( I figured this out AFTER figuring pulley sizes and hooking up a gen head) to teh correct 750 RPM with a VERY heavy load. The engine has been run on diesel, waste motor oil and bio-diesel (homemade of coarse  :)). I was disapointed that all of the oil will not drain from the sump. I had to mop it out with paper towels. But on the bright side there was no grit or metal in the sump. I was VERY happy with that. While in the process of changing the oil I added a short nipple and ball valve to make changing the oil a lot less messy the next time. The oil was dark but not as dark as I had expected. AS told by Mike (the man I bought the engine from) I had the cheapest 30 wt oil I could find in the crank case (Rotella next time). As for cooling I have an Apollo thermostat (ball valve) to restrict the water flow with untill the engine gets up to temp and a salvaged 40 gal. water heater tank.
          The engine is pulling a 5250 watt DeVilbiss piece o junk gen head (it was free). The head is making noise so it will be replaced before long. It will start a 3/4 HP sub. pump that is 300' down  :). Very happy with that. It runs anything in the shop I ask it to however it does not like to start the radial arm saw (the gen head). The motor will do any thing but the 4500 watt water heater element. Think I may drop to one 2500 wayy element and run it first for the hot water I need.
           How are you guys keeping up with the hours. Writing them down? Some sort of clock? just wanted to know. Sorry for the loooong post.

Thanks for all of your input.
Johnny Williams


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Re: First oil change
« Reply #1 on: January 02, 2006, 11:54:59 PM »

Good show (so far) on the new engine.  As for the hour meter, 12 v and 115 VAC engine hour meters are available all over the place.  This one is for 115 VAC and is only $16 and the one on the right is $25 and is for 12 VDC only.  The 115 VAC meter is probably a better bet because it can be hard wired into your panel and will run any time the generator is running.  You can power the 12 VDC unit using a "wall wort" power supply, but why go to the expense and added compexity?


One place every DIYer should know about is http://www.surpluscenter.com.  All kinds of neat stuff there.

« Last Edit: January 03, 2006, 12:00:31 AM by quinnf »


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Re: First oil change
« Reply #2 on: January 03, 2006, 01:07:16 AM »
Put an oil filter inside the inspection door, you will be amazed at the stuff it will pick up. :o
Check the OIL FILTER!! posts. Hotater went for the simple and easy method, got it tested and the results posted before I could even get my materials together. Yet I doubt my filter will work one iota better :-\
Scott E
Ashwamegh 25/2 & ST12
Lister SR2 10Kw 'Long Edurance' genset on a 10 gallon sump/skid,
Onan 6.5NH in an old Jeager Compressor trailer and a few CCK's


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Re: First oil change
« Reply #3 on: January 03, 2006, 01:56:49 AM »
Have a look at this hour meter / tach.




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Re: First oil change
« Reply #4 on: January 03, 2006, 04:52:16 PM »
Good show!!  That first oil change can tell you a lot.

 You didn't mention magnets---  Stick a couple strong one's to the inspection door....IF I had it to do over again, I'd put a couple big, strong magnets on the OUTside of the inspection door and turn the whole door into an 'iron dust' collector.  These engines shed a prodidious amount of this stuff.  Sit a couple in the sump to....in my case, anyway,  catch the teeth from the cam gear.   :-\

IT's SO easy to over-rev these engines when you don't have a tacometer of some kind.   I ran mine for a week before hooking up the ST head and seeing 70hz on the Kill-o-Watt!!

Here's a VERY cheap and so easy 'tacometer'---  Stick a piece of duct tape to the flywheel so it forms a little flapper.  Hold your screwdriver or wrench handle or fingertip so you can feel the flapper....I'll bet ten to one you recognize 650 per minute.  It's the exact same frequency as 'leg jiggles'.
  I kid you not.     ;D
7200 hrs on 6-1/5Kw, FuKing Listeroid,
Currently running PS-Kit 6-1/5Kw...and some MPs and Chanfas and diesel snowplows and trucks and stuff.


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Cheap Tach
« Reply #5 on: January 04, 2006, 12:45:13 AM »
The cheap model airplane optical tachs (see towerhobbies.com) work well set to 3 blades, then look for 1300 rpm if your flywheel has 6 spokes.  Point the tach through the spokes towards something light colored or bright, but leave off the AC lights.  In a pinch I've used a flashlight.

Glad to hear you came up with a clean (no sand) sump!

Best Wishes,