On a regular basis Lotus Marques overhauls water pumps for various Lotus Esprit models.
Some times the owner description does not match what is delivered to our workshop.
Here is an interesting case of a water pump being described as being "new" and having only been in service for about one thousand miles.
What arrived for an overhaul was a very second-hand pump that had recently been rebuilt and the drive flange welded to the bearing spindle.
This is unthodox weld appeared to be either a clumsy attempt to secure a lose fitting flange or a deterrent to prevent the pump being rebuilt.
For the pump to be dismantled and overhauled, the first step is to remove the front flange with the aid of a hydraulic puller.
Once the flange has been removed its then possible to press out the bearing and impellor as an assembly.
The offending weld was carefully ground off in an attempt to re-use the existing flange as a part of the overhaul procedure.
Unfortunately the weld had distorted the the flange and made it unserviceable so a new universal component was supplied and installed.
This water pump had previously been rebuilt after the bearing failed and allowed the impellor blades to make contact with the alloy body.
This action resulted in material being removed from inside the housing
The previous operator did not correct this problem by re-machining the area adjacent to the impellor blades.
A significant amount of material had to be removed before a continuous surface could be obtained
The impellor blade tips needed to be machined to restore the surface finish
The damage to the pump housing and impellor was caused by the bearing failing and allowing the blade tips to contact the alloy casting
Final clean and the new seal has been installed with Loctite grey MAXX, the pump is ready to be dummy assembled
The new mechanical seal is installed in with a custom tool and hydraulic press.
The impellor thrust face is machined and ceramic seal fastened to locating step
Fully assembled water pump that is ready for final check where its pressurised to 50psi
Overhauled pump and new gasket ready to be returned to Lotus Esprit owner
If Lotus Esprit owners encounter this problem then its vital to flush the entire cooling system to remove any debris that have escaped from the water pump.
In addition to this it is recommend you install a high quality corrosion inhibitor from Redline or Nulon (Nulon products available from Repco stores in Australia)
Some times the owner description does not match what is delivered to our workshop.
Here is an interesting case of a water pump being described as being "new" and having only been in service for about one thousand miles.
What arrived for an overhaul was a very second-hand pump that had recently been rebuilt and the drive flange welded to the bearing spindle.
This is unthodox weld appeared to be either a clumsy attempt to secure a lose fitting flange or a deterrent to prevent the pump being rebuilt.
For the pump to be dismantled and overhauled, the first step is to remove the front flange with the aid of a hydraulic puller.
Once the flange has been removed its then possible to press out the bearing and impellor as an assembly.
The offending weld was carefully ground off in an attempt to re-use the existing flange as a part of the overhaul procedure.
Unfortunately the weld had distorted the the flange and made it unserviceable so a new universal component was supplied and installed.
This water pump had previously been rebuilt after the bearing failed and allowed the impellor blades to make contact with the alloy body.
This action resulted in material being removed from inside the housing
The previous operator did not correct this problem by re-machining the area adjacent to the impellor blades.
A significant amount of material had to be removed before a continuous surface could be obtained
The impellor blade tips needed to be machined to restore the surface finish
The damage to the pump housing and impellor was caused by the bearing failing and allowing the blade tips to contact the alloy casting
Final clean and the new seal has been installed with Loctite grey MAXX, the pump is ready to be dummy assembled
The new mechanical seal is installed in with a custom tool and hydraulic press.
The impellor thrust face is machined and ceramic seal fastened to locating step
Fully assembled water pump that is ready for final check where its pressurised to 50psi
Overhauled pump and new gasket ready to be returned to Lotus Esprit owner
If Lotus Esprit owners encounter this problem then its vital to flush the entire cooling system to remove any debris that have escaped from the water pump.
In addition to this it is recommend you install a high quality corrosion inhibitor from Redline or Nulon (Nulon products available from Repco stores in Australia)