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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Sep 2007 Posts: 84 'Bolter | | 'Bolter Joined: Sep 2007 Posts: 84 | HOOOOOOWDY DOO: Just wanted to ask a question. I have '53 3100 I just got running after 23 years. Runs great...so far. Anyway, I have heard of some people changing the oil a few times in a brief period and mixing sligtly with diesel or kerosene to loosen up sludge. I've heard good and bad things about this. Just wanted to clear it up since I respect a lot of the opinions given here. Good or Bad idea?
Thanks
Craig
1953 3100 | 1958 3/4-ton NAPCO
| | | | | Joined: May 2002 Posts: 155 Shop Shark | | Shop Shark Joined: May 2002 Posts: 155 | I've used diesel to flush with no problems over the years..You only need about a pint, then drain after getting the engine warmed up.. You don't want to drive it around..if you don't want to go this route you can buy engine flush at parts house..
Geoff
68 GMC 3800 56 JD420C w/JD90 Loader
| | | | | Joined: Dec 2003 Posts: 2,733 Shop Shark | | Shop Shark Joined: Dec 2003 Posts: 2,733 | You'll get opinions both ways and probably some truth in both positions. Modern oils do tend to clean out the sludge but that can stop up some valve oiling tubes, maybe even clog up a pump. My advice would be to pull the side plate and valve cover and have a look see before doing anything. If it's really bad then maybe it should be taken down for a thorough cleaning. At a minimum that will allow you to clean out what you can see. If you start changing it I'd forget the diesel fuel idea in favor of 20W detergent motor oil and get it good an hot too.
Just curious but how does it sound after 23 years? | | | | | Joined: Sep 2007 Posts: 84 'Bolter | | 'Bolter Joined: Sep 2007 Posts: 84 | It sounds reeeally good. I was shocked when I first got it started. Not a lick of smoke out the tailpipe. I'm replacing the clutch now. The disc was stuck to the flywheel. I know I should be replacing seals, gaskets, bushings, etc. but I bought this truck to completely redo. I'm just curious if I get it running and driving while my shop is being built. The brakes are next. Once I get the clutch replace and make sure everything works I'm going over the motor in detail...compression check, valve adjustment, etc. I have already bought a 235 but want to keep the 216 for future contingency plans. Who knows I may put it back to original condition in the future. It's all original now. I'm certainly not going to butcher it up. I'll probably do the Saginaw/rearend conversion and then drop it just a little...that's it.
Thanks for the interest
Craig
1953 3100 | 1958 3/4-ton NAPCO
| | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | If it ain't broke, don't fix it. | | | | | Joined: Feb 2000 Posts: 987 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 987 | When I worked in the auto parts business. I would hear many types of "clean outs". There are 2 that I have used, one is Motor Flush and the other is a pint of ATF added to the oil and driven for a day or two then change your oil. However, I did neither of these on my 49 when I got it. I pulled the valve cover and found that the top end was getting no oil at all. I cleaned out all the return passages and then sucked the oil supply line clear of all the sludge that it had. Next I pulled the oil pan and cleaned everything. While I had the pan off I inspected the oil Pump. It showed signs of wear and while I could have reinstalled I decided to replace it and not chance it. Pulling the side cover and valve cover will give you a good idea to what the state of Sludge build up is on your engine..
Good luck
Brian Moore 1949 3100 5 window Deluxe "Today is better than yesterday, but not as good as tomorrow" | | | | | Joined: Oct 2007 Posts: 84 New Guy | | New Guy Joined: Oct 2007 Posts: 84 | I have always used a qt of Marvel Mystery Oil on a change. It will dissolve the crud, if any, including carbon deposits and will not harm seals or gaskets etc. Just my .0125 worth that works for me. Good hunting! dg
| | | | | Joined: Jan 2008 Posts: 502 Shop Shark | | Shop Shark Joined: Jan 2008 Posts: 502 | Craig, If it were me I'd pull the valve cover and assess the situation. If its so nasty I'd clean out what I could making sure oil is getting to the rockers and put the motor on a real frequent oil change interval. The addition of Marvel can be good and won't hurt. As far as any cleaning solution I've always remembered how much effort it takes to clean parts in a parts washer with a brush and think about some solution being able to clean the motor inside. I had a SB chevy motor once that was so nasty oil could not drain back from the heads so I cleaned out the drain holes and changed the oil a lot and was surprised at how well oil will clean things up over time. Even if there was a solution that could dislodge the crud would you want it running around in the motor.
Remember your freedom - US Veterans provided it. 101st Screaming Eagles
| | | | | Joined: Sep 2007 Posts: 84 'Bolter | | 'Bolter Joined: Sep 2007 Posts: 84 | All good suggestions. I think I will pull the pan off and clean it out. The marvel mystery oil is a good idea too. After that I think I'm happy. Thanks for the input. I was primarily worried about dislodging anything to plug up something.
Craig.
1953 3100 | 1958 3/4-ton NAPCO
| | | | | Joined: Feb 2006 Posts: 346 Shop Shark | | Shop Shark Joined: Feb 2006 Posts: 346 | I remember my dad back in the old days putting a quart of ATF in the engine about a week before he would change the oil. He said it helped keep the engine clean.
Terry K.
1951 5 window 1/2 ton
The only way to have a friend is to be one. -Ralph Waldo Emerson-
| | | | | Joined: Oct 2005 Posts: 1,317 Shop Shark | | Shop Shark Joined: Oct 2005 Posts: 1,317 | The only true way to clean 20 years of gunk from an engine is to hot tank it. I doubt that there is a solvent in existance that will safely remove the sludge that builds up from decades of non-detergent oil, condensation and gas contamination.
In fact, breaking a lot of the sludge loose, chemically or mechanically, unless the oil drainback holes in the head are completely plugged, seems like an invitation for disaster. The caked-on sludge is inert...it's not clogging up anything so why go to any extraordinary measures if you have decent oil pressure. I can see pulling and scraping the pan and making sure the screen in the oil pump pickup is open if there is a significant lack of oil pressure, but going any further if you're getting oil to the rockers is to me, counter-productive.
Once you've rebuilt the engine and it's been tanked and completely cleaned, the problem will be eliminated. IMO...keeping a 23 year old engine running until rebuild time would best be accomplished without any aggressive internal degunking.
Dave | | | | | Joined: Oct 2007 Posts: 84 New Guy | | New Guy Joined: Oct 2007 Posts: 84 | Just an aside, I learned of the MMO accidently. I left a set of pushrods from a sbc that were blocked with sludge and carbon laying half in and half out of a pan of MMO. They soaked overnight. The half that soaked was clean, the half that was'nt, was'nt! still plugged with crud. So I says to myself, hmmmmmmm! Again, my $.0128 worth. dg | | |
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