Forum for air cooled diesel engines and clones

[tmash]

i have been doing some reading of a service manual and am now wondering if my L100 has had the injector pump replaced with the wrong one at some point,
according to the manual there are two types, D and S, D being generator spec with max and min rpm of 3800 and 1200 compared to S spec of just 1900 and 600,
The pump on mine has the part number 100S1, im wondering if thats why its not wanting to govern properly at 3000rpm!

wish i had spotted that before spending so many frustrated hours playing around with it!

As far as I know, the difference between S and the D in speed is where the output shaft is connected to, crankshaft vs camshaft (half the speed). It will always run at 2000rpm + as recommended by the user manual, probably for the balancers to work or oil pressure minimums and there is no power below that anyways.
The differences between the pumps is sensitivity and stroke time at certain fuel flow settings, these effects happen mostly at full load. You need to adjust the throttle plate spring holes for non linear pressure on the lever. A worn out fuel pump exhibits the same symptoms having a a larger deadzone. (mine started doing that a bit at 700 hours with ULSD fuel)

Tmash.. have u given any thought that the oil might b coming from the bottom of the stud threads.??
Ifn it were mine:: id pull the studs (double nut method) and loc-tite’m in..
Be careful with the silicone.. IT WILL change the timing..
Good luck.

Thanks for the suggestion, I checked the rear of the studs with a mirror, thankfully they're visible and they were full of red sealant as well as around the threads in the front, will give this a try if it leaks again.
I've use a transparent film of grey RTV for now, applied warm.
I lightly sanded the copper shims to be close to a replacement part that's used for the other genny in surface, turns out there is some form of thick coating that I dismissed , and the 0.1mm shim has different thickness (probably bent and straightened) in a certain area that was visible after sanding with a flat glass piece on a glass surface in the second pic:

Before and after sanding in order.
The aluminium shim turned out to be concave from one side, I simply used ink and paper to verify. The copper shims also show the edges marks from the sides of the aluminium shims:

From left to right:

1. Copper shim face to alum. shim (some pressure coating crease caused by the concave alum. sides)
2. Copper shim face to fuel pump.
3. 0.1mm face to alum, notice the dark orange spot on the right, sanding flat didn't remove the coating, seems to be much thinner in that area, though no visible crease or bend, I replaced it with a new one.

 

[ponytug]

Tmash.. have u given any thought that the oil might b coming from the bottom of the stud threads.??
Ifn it were mine:: id pull the studs (double nut method) and loc-tite’m in..
Be careful with the silicone.. IT WILL change the timing..
Good luck.

I think it is an excellent suggestion, even if @tmash sees some sealant on the inside.

The thing that bothers me about this oil leak is that the oil on the other side is just splashing, and therefore pretty low pressure. It must be a pretty large crevice to leak out that much oil.

All the best,

Peter

 

[tmash]

(Oil drained under the Genset as well)

(Apologies due to the many uploaded images and replies)
Changed oil yesterday, since the drain tubing extension isn't long enough as I mentioned before and drained the oil warm this time, it leaked significantly inside instead of the usual drips while I was away, there is no tilt either and there is a tray under the engine without a slope for dripped oil that doesn't have welded corners and it leaked to the rest of the chassis bottom panel and drained in the cold air intake box, the intake metal tubing is close to the bottom for some reason and it sucked oil, the vents openings on cold air box are high for muffling noise? Now half of the air filter is full of oil, no oil after the filter or intake bend, the entire engine is dry, and I noticed the problem with the low frequency output and smoke. I removed the tubing for now and installed a new filter, the ambient temperature inside with a probe at the top near the intake/flywheel is only 30 C at 3.5kW and 16 C ambient, rises rapidly to 70c when the engine is shutdown after cooling for 5 mins no load.
The additional improvements whether it's the fuel pump roller follower shim or this intake turned out to be a terrible idea when executed by a junk manufacturer. A tiny hole in the intake body or the cold box bottom could have prevented this, or at least a longer oil drain extension.
Extension end is flush with chassis:

P.s It turns out that KAMA is a cheap copy of KIPOR, just a FYI for owners looking for spare parts for the KAMA.
Diesel sipper still a money pit, maybe not as close to an idling 10kVA 3cyl Genset wasting 1.2L/hour, 2 liter compare to 1 at 4kw etc.
At 2 months, the fuel cost is the cost of this Genset running 9 hours a day. If only I could get my hands on a Yanmar or single cyl Kubota.

 

[ponytug]

Thanks for sharing this. Yes, oil in the intake is going to clog a paper filter. I guess the lesson appears to be to remove any residual oil on the floor.

There appears to be a faint ring on the oil drain extension. Is that real? I.e. is it hitting the frame, perhaps on shutdown? If so, you might want to keep an eye on it.

All the best,

Peter

 

[tmash]

Thanks for sharing this. Yes, oil in the intake is going to clog a paper filter. I guess the lesson appears to be to remove any residual oil on the floor.

There appears to be a faint ring on the oil drain extension. Is that real? I.e. is it hitting the frame, perhaps on shutdown? If so, you might want to keep an eye on it.

All the best,

Peter

No problem, there is a half circle cut on the left of the extension and there is no ring there.
The hole close the engine is part of the engine seat, it doesn't move and there is 2mm gap.

Not sure how I can reach the pan to clean the oil, and the side in the photo is partial, the oil puddle is underneath the engine.
Can't drain from the chassis cooling vents either.
The cooling circulation flows from the only vent ports on the bottom under the alternator, so air sweeps under/around the alternator around the engine, sucked by flywheel fan to cylinder wall to the sealed and insulated exhaust box that includes the flexible exhaust part to muffler insulated box vents.
*E: the openings are as far as possible from the engine. And the floor there is wrapped with sound insulation.

 

[Dieseldan45]

Hello all, I have been advised to move this post to this forum.

Yanmar L70 excessive smoke!

I recently won a Yanmar L70EE off a government auction site, that I was wanting to swap on to a logsplitter. It starts, idles and runs great, however it never stops smoking even when warm. It doesn't appear to be using oil, smoke is a dark grey color with slight blueish hue.

I've tried so far:
-Different fuels, on-road and off-road diesel from different gas stations.
-Different oils, Rotella 10w30 and 15w40.
-New air filter.
-Cleaning the old injector, then replacing it with a new injector and shim.
-Removing and adding shims to the injection pump, supposed to change timing according to the manual.

Nothing has helped, it can sit there running for an hour, smoking away. It seems to me as if it is over-fueling, but I'm not sure what to try next at this point.

Any help is appreciated, thanks!

*In the pics the smoke appears more blue, think its my camera filter. In real life it is more gray.*

 

[ponytug]

Congratulations on winning the engine!

"When you have a hammer..." I have had the same issue with my L70 clone engine that I traced back to a tiny air leak, that was causing the injector pump to over fuel the engine. A minute amount of air interferes with pressurization of the high pressure line, which impairs the injector from spraying well, which causes incomplete combustion, which leads to more fuel being called for. Given that the engine looks brand new, this would be my first bet.

However, as the engine is new to you, I would suggest starting by running a can of Liquid-Moly Diesel Purge through it first, and then see where you are. There might have been gunk from some biodiesel left in the tank/fuel pump. I would double check the intake for blockages (mud dauber nest, mouse nest, etc.), just in case. If those don't fix it, I would loosen and tighten all of the high pressure diesel lines, and tighten the low pressure lines. Mine leaked at the fuel shutoff solenoid on the fuel pump.

As these engines were originally designed for high sulfur diesel fuel, I think it is a good idea to add a lubricity booster (SeaFoam, Opti-Lube Summer+, etc.)

Just my $0.02, but if it were me, I would route that fuel return hose anywhere but directly behind the muffler, and I would use cloth reinforced diesel tubing, rather than Tygon, preferably the VW / Deutz style with a cloth outer layer for some heat insulation and perhaps even an insulating sleeve. Diesel isn't that flammable, but why tempt things?

All the best,

Peter

 

[bmaverick]

With so many here needing assistance for the L-Series Yanmar engines, I happen upon this document on the Yanmar site. Hope it helps many of you here in this section.
1/13/2009 document

 

[goeduck]

Do the L series Yamahas tolerate running out of diesel without having to bleed the injector? Generator type application, where running until out of fuel is understandable.

 

[bmaverick]

Do the L series Yamahas tolerate running out of diesel without having to bleed the injector? Generator type application, where running until out of fuel is understandable.

Yamahas are gas engines and Yanmars are diesel engines.