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I've read recently that there were issues with the radiators, but don't know anything beyond that. Can anyone shed some light on this?The 213A first ran in 1940, but experienced lengthy delays before finally being declared "production quality" in 1943. Production was extremely slow to ramp up, in order to avoid delays in the existing Jumo 211 production.
Most of Junkers engine development department from 1937 to 1941 was working on the Jumo 211 and Jumo 222
The big Jumo 222 for the Bomber B has priority A wide away from the Jumo 213 which was a very very low priority engine for Junkers from 1937- first half 1941.
Not until the realy big problems of the Jumo 222 crankshaft and the stopping of the whole project through the RLM at the end of 1941, Junkers shift major development powers to the Jumo 213.
Here you can see that the Jumo 222 costs 3-4 years development time of the Jumo 213.
Junkers still did not give up. Using the original 46.4 litre displacement A/B design, they added a new two-stage supercharger including a trio of aftercoolers, one per pair of neighboring cylinder banks for high-altitude use, producing the 222E and F-series. Although sea-level performance was unchanged, the engine was able to produce 1,439 kW (1,930 hp) at 9,000 m (29,530 ft). By this point it appeared that the problems were finally being worked out, but bombing of the Junkers Motorenwerke's headquarters factories in Dessau made production almost impossible. A final attempt for even higher altitude performance resulted in the turbocharged 222G and H, built only to the extent of a few testbed prototypes.
Original 1937 specification for Jumo 222 engine required 2,000hp. Jumo 222 engine passed 100 hour endurance test @ 2,000hp during April 1941.
Then the political games began. RLM kept raising the bar for Jumo 222 performance in an apparent effort to keep the engine from entering mass production. Difficult to understand how or why that happened when the engine was badly needed for aircraft such as Do-217 bomber and He-219 night fighter. Even with "only" 2,000hp it was far superior to other engines powering those aircraft.
However Jumo 222 development and non mass production is a can of worms that belongs in a separate discussion.
I have a recollection that the firing order had to be changed to fix vibration issues.
Based on 1936 Jumo studies for a 1800 PS engine, in 1937 the RLM ordered a 1900 PS engine (24 cylinders, liquid-cooled) for left- and right-handed operation. Ferdinand Brandner, who was new at Junkers, was to develop this engine, which he projected as a 2000 PS, 6 rows of 4 cylinders design. It ran first in 1939 and in 1940 developed 2000 PS on the dynamometer and was flown as middle engine in a Ju 52. In 1941, it completed a 100 hour test on the dynamometer
The next generation of Jumo 222 engines had an increased bore for increased power. In December 1942 a 100 hour test at 2500 PS was completed successfully
https://groups.google.com/forum/#!msg/rec.aviation.military/9O6HdlO8waM/x01xZKPQxFcJ
So there you have it. 2,000PS during 1941. 2,500PS during December 1942. And RLM still didn't want the Jumo 222 engine to enter mass production. Strange behavior for a nation in a desperate struggle for survival.
From various sources came the claim, that the problem solved Jumo 222 crankshaft was in need for too much copper to put it in a serial production, without too much problems for other munitions.