One of our operators recently had a Simms in-line 6 element fuel injection pump of theirs overhauled and installed by a third party.
But unfortunately, after only one week of operation, there was a problem.
Two problems actually:
1. Camshaft housing full of fuel
2. Diesel spilling from breather when the engine was running
Oh, and for good measure, the engine speed was dropping off when under load, setting off an alarm in the process.
Having made these discoveries, they rightly had concerns about the spare fuel pump they had in stock, which had also been supplied by the same provider, so they sent it to us for inspection.
Initially, the pump appeared to be in good condition and recently overhauled.
But when we dug a little deeper, this too had issues, and lots of them:
- When the governor end cover was removed, we could see that whilst nothing was broken, there was no end cover gasket fitted
- The throttle shaft was bent
- The governor spring locating pin had been inserted incorrectly – the spring was mounted on the wrong side of the locating pegs
- The unit has at some point been contaminated with water due to pitting found on the control rod
- The control rod has several different markings indicating that adjustments have been made previously to fuel delivery
- There were two different types of delivery valves used – this would have caused a difference in the amount of fuel delivered by each element
- Each plunger and barrel were removed and again there were two different manufacturers plungers and barrels – this would have caused differences in the amount of fuel injected into each cylinder
- The fuel inlet and control head had been stuck in position with hylomar
- There were further signs of water erosion visible on the base of the control head assembly
- All the cam followers had signs of previous water erosion which has marked the bores of the main body. Fortunately, these marks have not rendered the body unserviceable
- The fuel pump normally has a small plate riveted to governor housing detailing the running speed, but this plate has been removed. To rebuild the governor correctly, the engine speed is required as there are three different springs available to suit different running speeds
As you can see, for a spare that was believed to be “ready to go”, it was a long way from it!
Before rebuilding, the control head will have the barrel seats lapped and the head pressure tested when all barrels and plungers are fitted.
We also recommend the pump is overhauled using parts from a single supplier/manufacturer to ensure correct calibration of fuel delivery.
If more accurate speed control is required, the operator should consider converting the unit to either external governor control or updating the internal governor.
No doubt there are many other operators holding spares that just aren’t reliable, leaving them open to painfully unexpected downtime and cost.
We are more than happy to inspect any spares or equipment you have, as well as your storage and preservation procedures, giving you the peace of mind that they are in suitable condition now and will stay that way until called upon.
If that would be helpful, just let us know.
