oil pump

[bigman1]

Hi i have a recurring problem with the oil pump on my 4107,the pressure releif valve keeps tripping,i have checked all the relevant faces with feelers,everything seems ok,with the pump specs.being in order it dosen't appear to be worn out.has anyone come upon this problem and what is the answer? also can the pressure releif valve be freed by blowing down the filter tube with compressed air,it's such a hassle removing the sump every time.Thanks.Ronnie.

 

[TQA]

Hi i have a recurring problem with the oil pump on my 4107,the pressure releif valve keeps tripping,i have checked all the relevant faces with feelers,everything seems ok,with the pump specs.being in order it dosen't appear to be worn out.has anyone come upon this problem and what is the answer? also can the pressure releif valve be freed by blowing down the filter tube with compressed air,it's such a hassle removing the sump every time.Thanks.Ronnie.

Explain what you mean by tripping?

A pressure relief valve is just a spring and a ball bearing and there is not much to go wrong.

 

[VicS]

Not actually a "ball" but a plunger, and a spring. Must be sticking if its really staying open.

See section L of the WORKSHOP MANUAL

Also clearances etc given in the technical data section

 

[bigman1]

re oil pmp

Hi i have a recurring problem with the oil pump on my 4107,the pressure releif valve keeps tripping,i have checked all the relevant faces with feelers,everything seems ok,with the pump specs.being in order it dosen't appear to be worn out.has anyone come upon this problem and what is the answer? also can the pressure releif valve be freed by blowing down the filter tube with compressed air,it's such a hassle removing the sump every time.Thanks.Ronnie.

Thanks For your replies,what i mean by tripping is the pressure relief valve keeps releasing the oil pressure and won't reset,i think vics is right in saying that the plunger is sticking,the first time i took the pump out,took out the split pin & plunger cleaned and lubed them with wd 40,it was ok for a while but this is the seconed time,i don't want this to happen at sea,i think i will replace the pump,you would think that there would be some other way to release the plunger other than removing the sump.Thanks Again.Ronnie.

 

[Seadog17]

Thanks For your replies,what i mean by tripping is the pressure relief valve keeps releasing the oil pressure and won't reset,i think vics is right in saying that the plunger is sticking,the first time i took the pump out,took out the split pin & plunger cleaned and lubed them with wd 40,it was ok for a while but this is the seconed time,i don't want this to happen at sea,i think i will replace the pump,you would think that there would be some other way to release the plunger other than removing the sump.Thanks Again.Ronnie.

A relief valve plunger sticking is fairly unusual, so no way of releasing it is fitted.

It has probably picked up a bit of dirt, which has scored the plunger body or the bore it rides in. You could try and hone the plunger in place with a fine paste, but it would probably be a lot more economical and easier to just replace the whole pump assembly.

 

[VicS]

Thanks For your replies,what i mean by tripping is the pressure relief valve keeps releasing the oil pressure and won't reset,i think vics is right in saying that the plunger is sticking,the first time i took the pump out,took out the split pin & plunger cleaned and lubed them with wd 40,it was ok for a while but this is the seconed time,i don't want this to happen at sea,i think i will replace the pump,you would think that there would be some other way to release the plunger other than removing the sump.Thanks Again.Ronnie.

While suggesting that the valve is sticking I would have thought that for it to do so there must be some obvious cause.
Spring OK? It should be exerting a force of several lbs on the plunger ( a quick calculation suggests something about 11 or 12 lbs)
Any ridges that the plunger could get caught on?

It should be pretty well lubricated in normal operation, ceratinly not requiring WD 40 which is a pretty poor lubricant anyway. It's a water displacing fluid.

Are you sure this is the problem ?.

It presumably opens when you start up with cold oil and fails to close again when the oil warms up and the pressure drops ?