Tores mailbox VIIC and VIIC/41 operation and technical details

[tore]

Simon, another small detail. It seems to me that you have made the fuelsupply pipe to the HP fuelpipe of copper, I believe it is of steel. The Laboe U 995 get a funny rusty look on the unpainted steelparts, see picture below where the steelhandles colour is identical to the fuel supplypipe whereas the real copperpipe has a different colour
Tore

[NZSnowman]

Simon
In addition to my last post the overhead drawing of the enginetop shows large circular objects between the cyl. covers inboard side. The engine is built up of caststeel pieces, the majors being the crankcase and the cylinderblocks. They are bolted together by mean of long tiebolts with nuts on the lower parts ( in the crankcase) and heads on top of the cyl. block. There are alltogether 14 tiebolts 7 inboard and 7 outboard, on the drawing 7 inboard and 1 outboard are visible. In order not to obstruct the fitting of the cylindercovers, the heads of the tierods are fitted in  recesses in the cylinderblock, the recesses are covered by  steelplates and that is the circles you see on the overhead drawing. By the way, putting the inboard cylindercover studs ( the short ones) in  recesses makes it possible to accommodate the rockerarm pedestals on the top.
Tore

Hi Tore

Again big thanks! I was going to ask you in a few days what this was on the engines. I have added the Tie bolts to my drawings. I also noted that I had missed them from the

[NZSnowman]

Simon, another small detail. It seems to me that you have made the fuelsupply pipe to the HP fuelpipe of copper, I believe it is of steel. The Laboe U 995 get a funny rusty look on the unpainted steelparts, see picture below where the steelhandles colour is identical to the fuel supplypipe whereas the real copperpipe has a different colour
Tore

Tore, thanks. I realise they are steel just have not found the time to change the colour yet. On the

[NZSnowman]

Final?  The details of cyl cover top. One item remains to be identified, the safetyvalve, which is a pressure reliefvalve and you can barely see the top protruding out of the cylindercover top. The place is indicated below.
The cooling watercock looks a bit strange, but it is because the function is you can lead the water out from the cylinderblock cooling either fully through the exhaustvalve (series) or partly ( parallel) depending upon the need.
Tore

Hi Tore

Thanks! I was going to ask you this question also Again added the new sub-system to my drawings.

[NZSnowman]

Simon. Excellent, this is going to be the best ( except for the design drawings) drawing of the GW M6V 40/46 engine made ever. A small detail, check the diameter of the HP fuelpipe in relation to the airpipes, particularly the controlair branch to the top of the startingair valve. It seems to me the fuelpipe is slightly too large or more probable the airpipes slightly too small.
Tore

Hi Tore
 
I am almost sure I know what pipes you are talking about, if so I also noted this and made the changes on the

[tore]

Simon. We are almost there I believe. Something with the drawing projection is a bit strange to me. You obviously are basing your first drawings on port  engine aft. The topview of the cover is  placing the valverods outboard, to me this is a different way of projecting. In order to prevent any misunderstanding I post a drawing to explain what I mean.
Tore

[tore]

Simon. By the way I guess I somewhere mentioned that the inlet and exhaustvalves were turned 180 degrees, I have to correct that. The exhaustvalves are forward of the inlet valves on both engines. See picture.
Tore

[tore]

Simon.
Pipedimensions.
May be a closer look into the starting airpipe branch off to the top of the startingvalve, and the main starting air supply pipe in relation to the HP fuelpipe would be worth while. See picture.
Tore

[tore]

Simon.
Cylindercover cooling.
I realize we haven`t gone into details on this subject. The coolingwater enter the cylindercover via pipebends from the cylinder coolingjackets.  The pipebends would the only visible part ( if at all). Out of the cover it enters the series/parallel coolingwater cock ( blue) which allow the water to go to the exhaustvalve cage, either partly (parallel) or all (series) depending upon the temperate reading on the thermometer, it is manually controlled.
The water from the cock then goes to the exhaust manifold coolingspace. The funny looking "spring" on the photo is, I believe, the handle for the cock, the springshape is a typical 1920/30 solution for heat insulation. The details to be seen are a bit unclear to me on this.
Tore   

[tore]

Simon.
Cyl cover- exhaustvalve piping.
Below is a picture showing my proposal of the piping, it might be the cockarrangement is different. This would be starboard engine, forward to the right. The cockhandle is on the other side of the cock and the ventingpipe ( blue ) is missing I believe.
Tore

[tore]

Simon.
Fuel supply pipe to HP pumps.
On your drawing it seems that somehow the collecting drain pipe is connected both to the lubeoil drain pipe from the governor servomotor and the fuel supply pipe to the HP fuelpumps. The collecting drainpipe runs along the engine about where the cylindercovers meets the cylinderblock and collect drain from each cylindercover via funnels. I guess it possibly ends up in the dirty lubeoil tank underneath the floorplates. Anyhow this relatively simple drainpipe has nothing to do with the other two systems. See drawing below.
Tore

[NZSnowman]

Simon.
Cylindercover cooling.
I realize we haven`t gone into details on this subject. The coolingwater enter the cylindercover via pipebends from the cylinder coolingjackets.  The pipebends would the only visible part ( if at all). Out of the cover it enters the series/parallel coolingwater cock ( blue) which allow the water to go to the exhaustvalve cage, either partly (parallel) or all (series) depending upon the temperate reading on the thermometer, it is manually controlled.
The water from the cock then goes to the exhaust manifold coolingspace. The funny looking "spring" on the photo is, I believe, the handle for the cock, the springshape is a typical 1920/30 solution for heat insulation. The details to be seen are a bit unclear to me on this.
Tore

Hi Tore

I am trying to sort out this handle. In the photo below you can see a handle on the exhaust outlet between the flange and the water cooling pipe. Do you think this is the same 'spring shape' handle you are talking about?

[tore]

Simon.
Cylindercover cooling.
I realize we haven`t gone into details on this subject. The coolingwater enter the cylindercover via pipebends from the cylinder coolingjackets.  The pipebends would the only visible part ( if at all). Out of the cover it enters the series/parallel coolingwater cock ( blue) which allow the water to go to the exhaustvalve cage, either partly (parallel) or all (series) depending upon the temperate reading on the thermometer, it is manually controlled.
The water from the cock then goes to the exhaust manifold coolingspace. The funny looking "spring" on the photo is, I believe, the handle for the cock, the springshape is a typical 1920/30 solution for heat insulation. The details to be seen are a bit unclear to me on this.
Tore

Hi Tore

I am trying to sort out this handle. In the photo below you can see a handle on the exhaust outlet between the flange and the water cooling pipe. Do you think this is the same 'spring shape' handle you are talking about?

Simon.
This is a bit hard to be 100% sure about. Below I have tried to clarify by putting a mirror picture of stb engine next to the your picture of port engine. As you see it is a venting cock right where the pipebranch to the common venting pipe should be and on the other side of the cooling bend is the pipebranch to the common ventpipe.
The only explanation I can give is that the common venting pipe has a shut of valve somewhere at the other end and that the extra ventingcock is a the end of the exhaustmanifold where air is likely to be trapped. By having the venting on this strategic place you can avoid to open up for all the venting which means a lot of water in the bilge. Anyhow I don`t think the end of the handle shown on your photo has anything to do with this, but is a handle placed on the opposite side of the series/parallel exhaustvalve cooling cock. For some reason not equipped with heat insulation handle.
Tore

[tore]

Simon
Just a small correction to my picture I see I have marked the main startingair pipe as a starting air valve, sorry.
Tore

[NZSnowman]

Simon.
Cylindercover cooling.
I realize we haven`t gone into details on this subject. The coolingwater enter the cylindercover via pipebends from the cylinder coolingjackets.  The pipebends would the only visible part ( if at all). Out of the cover it enters the series/parallel coolingwater cock ( blue) which allow the water to go to the exhaustvalve cage, either partly (parallel) or all (series) depending upon the temperate reading on the thermometer, it is manually controlled.
The water from the cock then goes to the exhaust manifold coolingspace. The funny looking "spring" on the photo is, I believe, the handle for the cock, the springshape is a typical 1920/30 solution for heat insulation. The details to be seen are a bit unclear to me on this.
Tore

Hi Tore

I am trying to sort out this handle. In the photo below you can see a handle on the exhaust outlet between the flange and the water cooling pipe. Do you think this is the same 'spring shape' handle you are talking about?

Anyhow I don`t think the end of the handle shown on your photo has anything to do with this, but is a handle placed on the opposite side of the series/parallel exhaustvalve cooling cock. For some reason not equipped with heat insulation handle

I now see that you are talking about, and I think you are right. Below is a better view of the series/parallel exhaust valve, you can see where this handle would attach to. Also you can see the other handle better.



PS. Made a lot of changes to my drawing today, listed below. Will post pictures in the morning, off to bed now

• Increase the pipe dimension of the Starting Air Main Supple on the