if it an't broke don't fix or should I

[timbatrader]

The diesel lift pump which is built into the injector pump on my loader (Chinese Mountain Raise MR926S)
is not pumping a replacement pump is dirt cheap if ordered from china so I got one on the way but anticipating a long delivery time I bought locally a 24volt universal pump to keep me going in the mean time the universal pump is working fine but now the genuine mechanical pump has turned up ( always when you don't need something in a hurry it turns up way before the quoted delivery date) so what should I do part of me say if its working fine just leave it alone the other part is saying return it to original spec what are the advantages / disadvantages of leaving as an electric pump over a mechanical pump

 

[piper184]

Since you have already gone to the work of doing the conversion and you know that the OEM is prone to failure, I would leave it as is. Put the new one on the shelf as a backup. Odds are you will never need it.

The mechanical pump on my Jinma used an O-ring to seal a sliding shaft instead of a lip seal. Couldn't keep them sealed and it constantly put fuel into the pump crankcase. Got tired of replacing the O-rings so removed the pump, made a cover plate to bolt in it's place and installed an electric fuel pump I had on hand for another long gone project. It has already lasted longer than the OEM and has had zero issues.

 

[Bob Rooks]

I'll second Piper's response - leave it alone and shelf the mechanical pump. I had the same dilution issues. My electric pump has been in service for several years now with no issues. Interestingly, my Mitsubishi excavator came from the factory with an electric lift pump, in fact, there isn't a provision to mount a mechanical pump. I assume you have a 24 volt system?