So as to not hi-jack the wide head mill topic. The talk of rpms from MM got me wondering. Is there not a way to change out the rpm governor on yaws diesel? When looking for a power plant for my mill build, i ran across a cummins 4bt that was pushing a lil over 100hp @3000 rpms. Granted it wasnt stock on the inside, but he did have a bit more rpm range and said he could go more but funds ran out, which was the reasoning for selling it.
Not sure how the injection system works on them kubotas duetz and lam engines, but im sure there is a governor plate in the pump somewhere. Or am i wrong in assuming that? Cummins and Cat can be turned, stands to reason other diesel engines could have the same mods available.
You really don't want to raise the RPM on a diesel, run them slower but not below the peak torque RPM. They use a lot less fuel at lower RPM. Steve
Yes, i know, but that is not why i asked. I used to have a highly modified cummins and know the fuel burn is a lot. I asked if it could be done simply bc if eng A: is wanted but not offered anymore, but eng B: is available et not as good as A: and eng C: will be the next newest and nowhere near A:. Then finding an endrun around the system is in order but there is ALWAYS a give and take.
Im not sure if I understand your question.
Sure you can tune up the diesel to make it run faster however for a mill blade speed is king and if you go over that speed you can see increased issues.
If you are trying to cut faster thorugh a log I think you might find issues with blade size instead of blade speed. By example you can cut faster with a 2in blade vs a 1.5in or even 1.25in.
I would read this blog, very good read.
How Fast Should a Bandsaw Turn and Does That Change for Frozen Logs? - Cook's Saw Store (http://cookssaw.com/blog/how-fast-should-a-bandsaw-turn-and-does-that-change-for-frozen-logs/)
Im referring to the lower rpm range for other diesels compared to others. MM said that his eng spins at around 3800. If other engs spin at say, 2500, turn the rpms up.
That prevents having to change puller sizes with the slower turning eng. i am NOT saying take the 3800 rpm and turning it up more. By doing so, a pulley change would be required to maintain same blade rpm.
As mentioned before its the torque curve you need to look at for each individual motor. Blade rpm is irrelevant if theres no power behind it.
If 1000 rom increase reduces the tq curve to an unusable level, it was the wrong eng eng to begin with. Cant expect a 4 cyl to produce the the output of a 6 cyl just by turning it faster.
I turned my cummins up 1200 rpms, opened the fuel, air and exhaust, and doubled my tq and nearly doubled my hp. Iv been working on diesels for 25 yrs, anything from 4 cyl, i/v 6 and from intl/navistar v8s, to big v8 detroits used in military tracks and heavy haul wheeled tcks.
Again, the eng has to be capable of handling the increased revs in the usable power ranges. Im not saying EVERY diesel can, im asking if the diesels available without the unwanted reqr garbage is capable of achieving the desired effects.
Quote from: charles mann on March 28, 2019, 10:50:00 PMMM said that his eng spins at around 3800
:o @charles mann (http://forestryforum.com/board/index.php?action=profile;u=41365) You would need to show me where I said that so that I can edit. :P
When sawing my engine is turning ~2950, and the idle speed is ~1500 RPM, both of which are measured and adjusted with a tachometer. The Wood-Mizer spec. calls for 3000-3100 sawing. The high idle speed is to assure that the alternator is supplying enough voltage to maintain the batteries.
There are very few Diesel engines rated for continuous operation at 3000, with most being in the 2500 range. Normal high speed for a Diesel is ~2200 which I would be hesitant to exceed.