Hey guys thanks for your responses. I do now have a new water pump. (the new ones have a SS boss as opposed to the light weight one you see in the photo. Since writing my post, I have been able to find out that the impeller is driven by gearing from the drive shaft (helical).
I don' think the thermostat id faulty as the water out the exhaust gets so hot you can't touch it. I have inspected the impeller and it looks fine bu the Jabsco service assistant has told me it is likely one of two things; a worn back plate or an impeller that has expanded and therefor would need replacing. There is a plug that should be fitted at the from of the impeller to stop wearing and fill and air gap in the assembly so that the vacuum in the impeller housing works better so I am going to replace the impeller and make sure the front plug is in place.
murray got a reaction from Andy135 in Ford 2711E impeller speed compared to engine revs
murray got a reaction from Saintly Fish in Ford 2711E impeller speed compared to engine revs
