M-82 / M-105 engines

[JtD]

But the K25 carburettor was pretty advanced for its time and for instance had automatic mixture adjustment. I tend to agree with Galway that it is unlikely the later I-16's suffered from neg g cutout, but one would have to be sure.

The K25 was also used with the M62/M63 engines, as was the K63 (AK-25-4DF and AK-63-TK). The technical descriptions of these carburettors, as far as I could find them, made no statement regarding the working principle (float or no float) or about behaviour under negative g.
---
OK, thanks SaQSoN.

[SaQSoN]

Originally Posted by JtD

The technical descriptions of these carburettors, made no statement regarding the working principle (float or no float).

K-25-4 family was all float, that's for sure.

[JG52Karaya]

Thanks everybody for your constructive posts,

I still have one more question, namely what the situation was on the AM-35/-38 engine family used on the MiG-3 and IL-2. Did these have float, floatless or injection type carbs!?

[SaQSoN]

Originally Posted by JG52Karaya

I still have one more question, namely what the situation was on the AM-35/-38 engine family used on the MiG-3 and IL-2. Did these have float, floatless or injection type carbs!?

Floatless carb.

[bugmenot]

Hi SaQSoN, can you translate this?

Решением ЦК ВКП(б) и СНК СССР от 26 декабря 1940 г. завод № 24 получил указание с апреля 1941 г. выпускать моторы АМ-35А с карбюраторами беспоплавкового типа. Такие карбюраторы были изготовлены, проверены в наземных и летных условиях. Но моторы с беспоплавковыми карбюраторами не были взаимозаменяемыми с обычными AM—35A, внедрение их требовало переделки некоторых узлов двигателя, а также посадочных узлов и капотов самого самолета. Несмотря на определенные преимущества беспоплавковых карбюраторов в силу отмеченных причин они не были внедрены в массовую серию, но более десятка машин с такими карбюраторами все же были изготовлены и сданы в строевые части [22].

http://wunderwaffe.narod.ru/WeaponBook/Avia/Mig3/04.htm

[WTE_Galway]

Originally Posted by SaQSoN

Engines M-25, M-25В, М-62, М-63 and М-82А were equipped with float carburetor АК-25-4ДФ or К-25-4Д. Some M-63 were equipped with float-less АК-63.

M-82Ф was equipped with float-less carburetor, М-82ФН - with direct injection system.

M-105 since 1940 were equipped with floatless carburetor К-105БП

PS Most of this devices were designed by Fedor Amosovich Korotkov and his design crew. After the war, with the rise of the jet era, he switched to jet engine fuel feed systems and his designs were again used in most Soviet jet engines until late 1980.

Thanks, very useful information.

[SaQSoN]

Originally Posted by bugmenot

Hi SaQSoN, can you translate this?

In short words, it says, that at 26 Dec. 1940, Soviet government issued an order to produce AM-35 engines with floatless carbs only. However, this order was not obeyed at full. Only some engines were produced with such carbs, while most were equipped with the float carbs.

This made me search more thoroughly through my vast reference library and I actually found there an original manuals for AM-38 and AM-35 engines. According to them, the engine was equipped with 4 float carburettors, installed after the supercharger, each carb. serving 3 cylinders. This carburettors were equipped with special devices, preventing fuel overflow at a negative G, which made those engine fully aerobatic (according to the said manual).