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Old 05-08-2008, 11:43 AM   #9 (permalink)
JoJotheTireMan
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Quote:
Originally Posted by diesel_john View Post
My comments are in bold
Welcome
Where do I start?
Good technical writing job by the way.
Thanks, I also write technical software manuals as part of my main job, but much rather write about mechanical stuff
Dido everything said so far.
Posts are a great place to get rid of those annoying inventions.
Usually if someone tells me it wouldn't work, I try it.
So, is that your idea of pushing me to try this?

Probably the one of most efficient piston engines would be a slow turning, one cylinder diesel under full load 100% of the time. (diesel/electric)
True, diesel/electric to make it driveable, or just a diesel with say lots and lots of gears, I mean we have 21+ speed peddle bikes for that same reason, right?

Yes, IMHO, your idea will function.
In the big picture, IMHO, friction, pumping losses, etc. will eat up any possible gains. I am by no means an expert on engine cycles.
Well, I guess there is only one way to know for sure

You can advance search on a user name and see all the posts a user has started.
Thanks for the tip, as I am new to this particular site.

I got your email, and what i am going to do is take out #2 & #3 pistons from a vw diesel. Take out the valve actuating buckets. Cover the oil holes in the crank with a hose clamp. Pipe the fuel from 2 & 3 to a flow measuring device and return that fuel to the tank. Use my gear shift lever a lot more. Also i am trying to figure out how run an alternator with my exhaust gas. So i can eliminate the the accessory drive belts. I don't want to hyjack your post.
OK, so your idea is similar but different. Your simply trying to reduce your 4 banger diesel to a 2 banger diesel. Let assume for a minute that you have zero loss from the 2 missing jugs, will half the HP/TQ of your motor be enough to power the car? That is where I figured it wouldn't be enough, so I was trying to put the unused cylinders to work somehow. Granted you have more TQ to start with being a diesel. The good part of your plan is, other than the time to tear it down and put it back together and some gaskets, there isn't a huge cost factor here, and it would be reverseable if need be.

Questions.
What type of fuel injection do you have?
Electonically pulsed multi port injection
Will the cam clear the valve stem if you take out the buckets? (or is that boo-kay)
That I am not sure of, as the bucket is not all that thick. You could always just grind off some lobes of a spare cam, no? Removing lobes is a lot cheaper than adding some. On second thought, look up the cam specs, find the max valve lift and compare that measurement to the thickness of the cam follower buckets, add a little leaway for heat expansion and it may just clear the valve stem simply by removing the cam follower bucket.
Would an umbrella type valve seal keep oil from getting sucked down the deactivated valve stems?
I don't know if the umbrella seal would prevent all oil from getting down the valve stem, but if the valves are never being opened in your case then there is no suction at those valve stems. In my case, yes I will have oil being sucked into my air pumps, small amounts, but yes it would be sucked down I would imagine, but a little oil never really hurt anything as just about every motor out there burns some oil to some degree.

I do like your idea, and I could go that route with a gas motor too, but I have a funny feeling that it just wouldn't produce enough HP/TQ to run smoothly and/or be very usefull in every day driving. But you may be able to get away with it on a diesel due to the increased TQ at lower RPMS. Best of luck with your experiment, JoJo
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