danda Posted May 22 Share Posted May 22 I imagine this will be an ongoing thread as I have this old ud18 that was my fathers and it got left in the rain with one exhaust open for several years. There was a tin can over the exhaust but eventually it rusted through. The engine has sentimental value for me as I remember my father running it on his sawmill when I was kid circa 1983, and I'd love to see it live again, after 40 years of sitting. The engine was in great shape before it sat, so no known mechanical problems. My tIme, funds, and expertise are limited and the engine will almost certainly have to be torn down and rebuilt... so this could take a while, maybe years as I tend to get sidetracked with other projects around the farm. It will be the first engine I attempt to rebuild all by myself, and a tricky one since parts are hard to come by and $$$. So I'm definitely gonna be asking y'all for advice from time to time. Other times I will just post some pics, updates, etc. Initial status of the engine was: engine stuck, stuck, stuck. no obvious cracks in block or head(s). compression release mechanism stuck. 3 valves appear stuck injection pump: unknown if stuck or free. (Bosch) fan blade (water pump) rotates clutch works. (unit has a flat belt drive, which spins in neutral, stops when engaged) has an electric starter. untested, presumed dead. has a bigass manual crank. It seems something is broken, so the crank only barely engages. thick grime in the rear head when I removed the exposed exhaust manifold. manifold itself seems surprisingly ok. (not all rusted away) front head comparitively clean after removing intake and exhaust manifolds. minor rust visible in the cups underneath injectors. Tomorrow I may have some pics to share. I just got a new endoscope also, so I can check out condition of pistons/cylinders. Right now I am hoping that someone out there has a service (or parts) manual for an old ud18 with the two separate exhaust manifolds and the rounded intake manifold. I need the pages that discuss (dis)assembly of the intake manifold and the funky housing above it that does compression release stuff. The older intake manifold is identifiable because it has 3 bolt holes at top center. The newer (i think) one has 4 bolt holes and removable covers at left and right side. My problem (one of many) is that the compression release mechanism is stuck inside either the intake manifold or the above housing or both. There appears to be a single valve, much like an engine valve, that extends into the intake from the housing above and I'm guessing it is this valve that is stuck. So the housing can't be removed from the intake yet. I have the intake and housing off the engine, soaking first with penetrating oil and now with diesel. There is a little 2 inch lever that is supposed to actuate the mechanism that gives me a place I can (lightly) tap with a hammer in both directions. I actually have 3 different service manuals that say ud18 and ud18a, but all three discuss the other (newer) type of intake manifold which seems to work quite differently. I found on ebay just now a parts manual that clearly shows my type of intake manifold, so I will order that. The good news is that I got all the rest of the compression release mechanism working: lever freed up, starting valves are free, carb is free, linkage is free, and it will catch in start position and release to diesel like it is supposed to. So I'm calling that a win. My immediate goals are: get the intake manifold freed up. get pictures inside the cylinders. (might have to suck out some diesel). either get everything back together, or create a proper way to store/label parts and prevent further dust/corrosion of exposed parts while I work on it. The engine is under a metal roof, but no walls, so exposed to dust, humidity, etc. Sorry no pics yet. My phone was dead this morning. 1 Quote Link to comment Share on other sites More sharing options...
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