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[TheLongBuild]

I may have , Damaged  my safety valve.  The first steaming today went very well , until the end where it appears that I had not put enough water in to outlast the burner ( Using boiled water probably did not help either) as this probably meant I had too much fuel..

When steaming up the valve is reacting way too early and not allowing any pressure to build up.

The engine is a Modeen and before I do any further damage can access be gained to the spring and ball bearing to possible replace the spring ?. as it did get rather hot  and I feel I may have damaged it.

[AlexC]

I may have , Damaged  my safety valve.  The first steaming today went very well , until the end where it appears that I had not put enough water in to outlast the burner ( Using boiled water probably did not help either) as this probably meant I had too much fuel..

When steaming up the valve is reacting way too early and not allowing any pressure to build up.

The engine is a Modeen and before I do any further damage can access be gained to the spring and ball bearing to possible replace the spring ?. as it did get rather hot  and I feel I may have damaged it.

Hi,
I doubt that you have damaged the safety valve, they are designed to get hot.
It probably just needs adjusting for correct release pressure.
 
This is usually done by screwing in-or out the top centre piece on the valve... you may have a screwdriver slot or some small holes at the top.
 
You need to adjust it against a known calibrated gauge using hydraulic pressure.
 
If you belong to a club then your club's boiler inspector should be able to do this for you.
 
I hope this helps.
 
Best regards.
 
Sandy.

[TheLongBuild]

Hi
thanks for your reply,there are no holes or slots on the top,so no obvious entry area.

[AlexC]

Hi,
 
That's not very good then.
 
I would suggest you replace the safety valve with an adjustable one having the same thread.
You need one that will suit the pressure range 25psi - 45psi as I would think your boiler is rated at approx 30psi.
 
There are several sources: -
 
http://www.clevedonsteam.co.uk/products.html#Safety Valve
 
http://www.maccsteam.com/Fittings/Fittings.html
 
http://www.pollymodelengineering.co.uk/sections/bruce-engineering/docs/Catalogue-May-2014.pdf
See Page 43 of catalogue.
 
You will still need to set the correct release pressure.
 
Hope you get sorted.
 
Best regards.
 
Sandy.
 

[rpbidgood]

Hi,
I am intrigued by your problem - there must be some way of adjusting the valve, and similarly there must have been a way of introducing the spring/ball into the valve body. When I have made safety valves I tend to machine the body and threaded part from a single piece of hex bar, but, if you look at the attached picture you will see that in this instance the threaded part is a separate item which screws into the valve body and is secured by the locknut in the middle. Interestingly enough the lock nut is absent from your device, but the threaded bit could be held in place with some form of loctite. It is conceivable that the valve was adjusted by screwing the threaded portion in and out of the valve body, but this is pure conjecture and I could be talking a load of rubbish. If you want to test this you will need to locknut two nuts together on the threaded portion and try and screw/unscrew using a pliers or suitable spanner  (the lock nuts prevent the thread being damaged). I hope I've made sense.
Keith.