kh oil pressure

[kevinbowman]

since rebuilding my kh the oil pressure is sky high on start up and riding along it goes up to 100 and on tick over it reads around 25. i sent the oil pressure gauge away to have it cleaned and checked out so would assume it to be working ok. Also after doing about 200 miles so far and re tightening the head down 3 times it has started to leak from the rear of the head the question is are the studs in the head difficult to remove as i want to check if the head is flat, also is a solid copper gasket available for this model ? thanks in advance for any pointers kevin bowman

[Paul Slootheer]

Kevin,
My 1952 KH also gives aprox. 100 psi when cold and I'am running it on Multigrade oil 20W-50. On riding conditions so when the engine is realy warmed up pressure drops to around 75 psi. (at 50mph) It also depends how warm the weather conditions are... Last week it gave only 15-20 psi on tick over and 65psi riding, but then the oil was very very hot due to the hot weather conditions of 32 degrees celsius! I do not pressure feed the cylinder head by the way, so all the pressure is routed to the big ends!
It is worth to check your oil pressure relief valve at the end of the crank!
I did make use of the head gasket with on both sides a thin copper layer. Is does work on my motorcycle.
Regards, Paul

[kevinbowman]

Paul, Thanks for the reply i am also running on 20/50 oil so am getting the same oil pressure as your bike that is good as i was thinking something was wrong. i think the next step is to remove the head and check to see if the faces are flat and re fit with a new gasket. One more question do you use any sealing compound on the head gasket or do you fit it dry. i fitted a new ball and spring from Dragonfly so assume it to be ok.

[Paul Slootheer]

Kevin, I do not know what year your KH is, but unfortunately KH's can have issues like blown head gaskets... If you are running a iron engine I can't imagine your head is warped, but you always can check. The later aluminium heads make use of an extra stud in the middle of the head. Just a light smear of grease on both sides wil do the job. Retightening a couple of times after you run the motorcycle is a must. Removing the studs can be done by securing two nuts against each other and then turn the stud out of the head.
Regards, Paul

[kevinbowman]

Paul, thanks again for the reply, yes it is an iron engine 1951 will remove head during the winter months and check for flatness then refit with new gasket using a smear of grease regards kevin

[admin]

I do not pressure feed the rockers either, that is done from the return line.
My gauge is around 50-80 at speed, depending on temperature, and is directly attached to the original oil take off for the rockers.

I had an awful time with pressure readings (zero) and over-oiling at the top end, before I switched to the above configuration.

I run 20/50 as well.

[Paul Slootheer]

John I did exactly the same configuration, and all oil pressure is now where it belongs: on the shells.

[kevinbowman]

regarding the modification re the oil feed to the rockers. The original oil feed is taken from the base of the engine via a copper tube to the rockers. could you please explain how this is done as i did not know about this till i received your replies to my questions about oil pressure and would like to do this to my bike. Again thanks in advance for your help kevin bowman.

[Paul Slootheer]

Kevin, I placed a oil cartridge filter (keeps the oil clean!) between the return line to the oil tank. Because the oil is ''forced'' through the filter towards the oil tank this creates some light pressure in the return line before the filter. In taking a bleed with a T-piece and direct this to the head this will lubricate the rockers etc. That is the assumption. Just block off one of the connections on the head as John shows on his picture. The connection from the base of the engine can be fitted directly to the oil pressure gauge. I used a lenght of a Norton Commando flexible oil line, which feeds the head. You can read some more information in: ''Member bikes, The KH project'' page 3 or 4. If wanted I can send you some more photographs
Regards, Paul

[admin]

You need a T-piece in the return line - in/out and up to the rockers
The gauge is fed directly from take-off on the crankcase
One of the ends on the rocker feed spider needs blanking.
use flexi pipe as it's much much more user friendly

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