Tores mailbox VIIC and VIIC/41 operation and technical details

[tore]

Hi Tore

As I have no photo's of the starting valve system, it extremely hard to get a accurate drawing, so I am drawing the cross-section to help me in the other views. How does this look below? I am still adding detail to the drawing.
 
Thanks, Simon.

Simon, the crossection drawing behind your startingvalve drawing is one of the best I have seen so far. Do you have a full section? That could help a lot in explaining the various components
Tore

[NZSnowman]

Hi Tore

Here a original German photo that show the valve on U-564, also very interesting is you can see that the have painted the inside of the rocker arm.


(source: U-boat War Patrol - The Hidden Photographic Diary of U564 By Paterson, Lawrence)

[tore]

Simon.
Painting of the engines did not`t have a navy code and was for us anyhow something which was up to the engineers, sometimes overruled in extreme cases by the chief engineer. One rule however, moving machined parts,springs, shafts,handles etc was always kept shiny metallic. Painting inside the valve rockerarms would be OK particularly if you have a metallic rim as seen on the picture. On Laboe U 995 painting is far overdone and moving parts are painted to such an extent that they look like they are  casted (intgrated) to F.I. a fulcrum.
Tore

[NZSnowman]

I imagine on a long patrol at sea, someone in the engine room got bore and decided to full a few days painting things 


Added a little bit more detail. Tore, how does the new parts look ok?

[tore]

Yes Simon I have experienced that more than once. We had one guy once who painted all the nuts on the engine red. It looked horrible and we came to the conclusion the engine got the measels. I revert in a minute as to your new details on the cylindercover.
Tore

[tore]

Simon , I am still puzzled about you sort of half rocker arm (the black outline). This is a full rockerarm ( yellow) and gets in contact with the valvespindle and lower it so the startingvalve opens. Se my picture below. Otherwise everything looks nice.

[NZSnowman]

Hi Tore.
 
No need to be puzzled about the half drawn rocker arm as I only did this drawing to help me with my

[tore]

Simon. Great very interesting to see how you do it!
Tore

[NZSnowman]

Tore, this is the best I can currently do with the starting valve system with the photo's & plans I have. I am sure there are missing details but that will have to wait to till we get more information.

[tore]

Simon. It is definitely getting better! When the reminding items get into place it shall be cramped.
Tore

[tore]

Simon.
Cylindercover bolt/nuts
The arrangement and look of the cylindercover bolts and nuts migth be a bit confusing. The cyl. covers are bolted to the cyl. block by 8 bolts symmetrically placed as the yellow dots on drawing below. The confusing part is that you don`t see the two inboard nuts marked purple on the drawing. I guess they are placed in recesses under the exhaust/inletvalve rocker pedestals. The reason would be that these studs don`t go all the way to the covertop as they would obstruct the dismantling of the cover. Sleevenuts would be used to reach the shorter studs in the recesses and the top of the nuts shall be flush with the cyl. cover I guess. Anyhow, for your drawing it means, I believe, the yellow nuts are the only to be visible.
Tore

[tore]

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

[tore]

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

[NZSnowman]

Simon.
Cylindercover bolt/nuts
The arrangement and look of the cylindercover bolts and nuts migth be a bit confusing. The cyl. covers are bolted to the cyl. block by 8 bolts symmetrically placed as the yellow dots on drawing below. The confusing part is that you don`t see the two inboard nuts marked purple on the drawing. I guess they are placed in recesses under the exhaust/inletvalve rocker pedestals. The reason would be that these studs don`t go all the way to the covertop as they would obstruct the dismantling of the cover. Sleevenuts would be used to reach the shorter studs in the recesses and the top of the nuts shall be flush with the cyl. cover I guess. Anyhow, for your drawing it means, I believe, the yellow nuts are the only to be visible.
Tore

Hi Tore
 
This is fantastic! I do not realize that were was eight cylinder cover bolt/nuts. This is the detail I love I have updated both my drawings (top and side views). Below are the updated drawings, it a little hard to see all the cylinder cover bolt/nuts.
 
Thanks, Simon.

[tore]

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