I posted a few months back about running problems with my Deutz F2L511 in my Bobcat 731 and wanted to follow up in case others search. It would only start on the enrichment and would soot like crazy then die after 20-25 seconds as it slowly lost rpm. Initial Observations Did not appear to have excessive blowby. Fired right up Excessive black smoke indicating excessive unburnt fuel Knocking loudly(it had always done this, turns out it was broken since I got it) Valve adjustment was correct (0.006" I & E cold) Testing First thing I did was pop test the injectors and they were ok. The lift pump and injection pump had recently been replaced. I found someone who had the compression tester for these engines. It is a special piece and saved me machining an adapter. Cyl 1 had 16 Bar (232psi) and Cyl 2 had 30 Bar (435psi). This meant it was time to go inside the engine. Disassembly Removed the heads and it was evident the Interface ring on Cyl1 (Deutz's headgasket) was leaking. While cleaning the cylinders I noticed Cyl 1's piston had alot of play. In excess of 0.100" vertical. Rod bearings likely shot. At this point I pulled the engine and completely tore it down. The crank was wiped along with the #1 rod being oblong. I purchased a minor rebuild kit, a connecting rod, and new crankshaft from DK Engines. The parts are from Memo and are aftermarket replacements as OE Duetz stuff is very pricey if its available. I had to clearance the block to clear the counterweights on the aftermarket crank. They were slightly different than the oem crank. The new rod needed extra clearancing to clear the camshaft. The thrust washers were too thick and the crank would lock up. I machined them down in my lathe and lapped them to get the correct crank endplay. All in all I am very happy with the rebuild, test fired the engine today on the ground. It appears to run good with good oil pressure. Ready to get it put back in and get another 4000+ hours out of it (hour meter is broken). I have learned a great deal about these Deutz diesels and they are very easy to work on. Just be very detailed and very thorough in your work. If I can ever figure how to post pictures I will. I took this opportunity to paint the chassis and lean up some other items as well.
