Hey all. I managed to snag an old Yanmar YM226D for cheap the other week that was reported to “Have water in the fuel and wont run.” From my understanding, it’s a pretty common issue. All filters have dates from 2017 on them so I assume its been sitting unused for at least 7 years. Its rough, but the foundation is there so I figured at the price point it would be worth it as a project. Im pretty sure its an old landscape or golf course tractor given the turf tires and rough state of things. Hour meter broke at some point so zero clue on the real hours, but the condition of the loader tells me it was rode hard and put away wet.
Sure enough I drained 4 gallons from the tank, and only 1 gallon of it was diesel. Someone tried to run it, thus they pumped this fuel flavored water through the injection system. The injection pump rack and gears were seized and the internals were nasty. I cleaned everything, polished the plungers and bores, and reassembled with fresh diesel exactly as verified per factory manual. As of right now there is no fuel control. Regardless of rack position the pump is 100% full fuel and I am beginning to think someone was in it before me and it wasn’t assembled as it should. I didn’t touch the metering screws, or ‘Barrel adjust screws’ as the manual puts it, and without a flow test workbench, there isn’t anything I can do about that, so it looks like its time for a new IP and injectors. Am I missing something else here? The governor checks out based on inspection, but manually cycling the rack nets zero change in pump fueling volume. Two of 3 injectors literally pulled out by hand after removing the retainers, and the third just with channel locks, and none had the crush disc under them, so further telltale signs someone has been in there previously. The lack of any fuel on the return side of the injectors when priming and throughout the starting process tells me they aren't functioning properly either.
Regardless, I got it on and primmed the system to flush the injectors. In the process of spinning over the engine with the decompression off I discovered substantial amounts of black fuel/oil mix coming out of the exhaust ports with each cycle. I did get the engine fired, but it took a heat gun at 1500F in the intake for it to catch (65F ambient temps), and it smoked like a banshee while still spitting out oil and gunk from the exhaust ports.
The other issue; While initially turning over I let go of the starter and the engine tried to catch briefly, but stalled near TDC during a compression stroke and kicked back which was apparently enough to spin it backward with the force necessary to start it in reverse rotation. The full fuel situation brought it up in RPM fast before it then ran away on me. I assume it was eating this oil mix. Very unexpected to say the least and my typical “starve the intake” response wasn’t an option, for obvious reasons. Decompression rack saved the day. Throughout the troubleshooting process this attempted reverse running has happened 3 times now along with numerous kickbacks that didn't result in a start. I have never had a non-2-stroke kickback and try to start in reverse rotation. Is this a sign of a well worn engine or possible a sign of way out of sync timing? Checking the service manual, setting timing for the engine is very…..rudimentary….to say the least.
I cant seem to diagnose where the oil is coming from either. Could be bad rings, worn cylinder walls, worn out valve guides/seats, etc. Crank case breather was disconnected and engine was given ambient pressure so I know it isn’t a blocked breather. The fact that its pulling oil like that though cant be good. With no-start/hard starts with temps at 65-70F without a heat gun, excessive smoke, major oil consumption, and the desire to run away via its own oil, is it safe to assume the engine is merely a core and ready for a complete in-frame of both the bottom and top ends? There are a couple of suppliers where pretty much everything can be sourced for not that much money. Only thing I haven’t found though is a camshaft. Is an engine that is functioning in the above manner(s) worth doing this work to or would it be more advisable to source a different replacement engine? I guess, other than doing a full sleeve/piston, bearing, gasket, fuel system overhaul and verifying the crank is still within spec, is there anything else that needs to be looked at/planned for? And prior to purchase of parts, is/are there specific things to inspect to ensure overhaul is worthy or would be a waste of time and relegate this particular block to a boat anchor? Curious what you guys think given that this engine (3T75HA) is prevalent across the JD lineup of compacts as well.
As far as suppliers, is there a preferred one? I see Southern Farm Equipment, Allstate AG Parts, Brand M Parts, and Yesterday’s Tractors. Parts selections seem to vary between.
For your entertainment, the very first start which turned into a backward rotation run-away event I actually caught on camera. Not sure why I hit record, but I did, and you can hear it hit full fuel, and then suddenly begin its best impersonation of a an ‘ole screaming Jimmy Detroit. Let me tell ya, hearing RPMs like that from a little 3 cylinder while standing over/alongside it gets the blood pumping fast, especially as you reach over to try and get it shut down.
Sure enough I drained 4 gallons from the tank, and only 1 gallon of it was diesel. Someone tried to run it, thus they pumped this fuel flavored water through the injection system. The injection pump rack and gears were seized and the internals were nasty. I cleaned everything, polished the plungers and bores, and reassembled with fresh diesel exactly as verified per factory manual. As of right now there is no fuel control. Regardless of rack position the pump is 100% full fuel and I am beginning to think someone was in it before me and it wasn’t assembled as it should. I didn’t touch the metering screws, or ‘Barrel adjust screws’ as the manual puts it, and without a flow test workbench, there isn’t anything I can do about that, so it looks like its time for a new IP and injectors. Am I missing something else here? The governor checks out based on inspection, but manually cycling the rack nets zero change in pump fueling volume. Two of 3 injectors literally pulled out by hand after removing the retainers, and the third just with channel locks, and none had the crush disc under them, so further telltale signs someone has been in there previously. The lack of any fuel on the return side of the injectors when priming and throughout the starting process tells me they aren't functioning properly either.
Regardless, I got it on and primmed the system to flush the injectors. In the process of spinning over the engine with the decompression off I discovered substantial amounts of black fuel/oil mix coming out of the exhaust ports with each cycle. I did get the engine fired, but it took a heat gun at 1500F in the intake for it to catch (65F ambient temps), and it smoked like a banshee while still spitting out oil and gunk from the exhaust ports.
The other issue; While initially turning over I let go of the starter and the engine tried to catch briefly, but stalled near TDC during a compression stroke and kicked back which was apparently enough to spin it backward with the force necessary to start it in reverse rotation. The full fuel situation brought it up in RPM fast before it then ran away on me. I assume it was eating this oil mix. Very unexpected to say the least and my typical “starve the intake” response wasn’t an option, for obvious reasons. Decompression rack saved the day. Throughout the troubleshooting process this attempted reverse running has happened 3 times now along with numerous kickbacks that didn't result in a start. I have never had a non-2-stroke kickback and try to start in reverse rotation. Is this a sign of a well worn engine or possible a sign of way out of sync timing? Checking the service manual, setting timing for the engine is very…..rudimentary….to say the least.
I cant seem to diagnose where the oil is coming from either. Could be bad rings, worn cylinder walls, worn out valve guides/seats, etc. Crank case breather was disconnected and engine was given ambient pressure so I know it isn’t a blocked breather. The fact that its pulling oil like that though cant be good. With no-start/hard starts with temps at 65-70F without a heat gun, excessive smoke, major oil consumption, and the desire to run away via its own oil, is it safe to assume the engine is merely a core and ready for a complete in-frame of both the bottom and top ends? There are a couple of suppliers where pretty much everything can be sourced for not that much money. Only thing I haven’t found though is a camshaft. Is an engine that is functioning in the above manner(s) worth doing this work to or would it be more advisable to source a different replacement engine? I guess, other than doing a full sleeve/piston, bearing, gasket, fuel system overhaul and verifying the crank is still within spec, is there anything else that needs to be looked at/planned for? And prior to purchase of parts, is/are there specific things to inspect to ensure overhaul is worthy or would be a waste of time and relegate this particular block to a boat anchor? Curious what you guys think given that this engine (3T75HA) is prevalent across the JD lineup of compacts as well.
As far as suppliers, is there a preferred one? I see Southern Farm Equipment, Allstate AG Parts, Brand M Parts, and Yesterday’s Tractors. Parts selections seem to vary between.
For your entertainment, the very first start which turned into a backward rotation run-away event I actually caught on camera. Not sure why I hit record, but I did, and you can hear it hit full fuel, and then suddenly begin its best impersonation of a an ‘ole screaming Jimmy Detroit. Let me tell ya, hearing RPMs like that from a little 3 cylinder while standing over/alongside it gets the blood pumping fast, especially as you reach over to try and get it shut down.
