It’s time for the final part of getting the boat’s engine & drive back together, now I have the new coupling hub. I decided to address one of the issues with the pump mounting while I had everything in bits. When the hydraulic drive was installed, a custom plate was laser cut to fit the pump stack to, as we had no bellhousing with a standard mounting pattern.
Even though this plate is 10mm steel, under full load it actually bends – so to strengthen it along the long edge, I have welded a pair of ribs to the plate.
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The mounting plate as removed from the mounting brackets. The slotted holes at the sides allow for some movement to adjust the position of the pump & flywheel coupling.
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I ground off the paint & grease with an abrasive disc, and am replacing one of the pump mounting studs while I’m at it.
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Here’s the plate after welding. a pair of 10mm bars have been attached along the edges, this will give the mounting significantly more strength on the long axis & prevent any deformation.
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Here the plate has been loosely mounted on it’s brackets, & I’ve got the pump stack with it’s associated tangle of hoses on the chain hoist. This unit is very heavy on it’s own – a 2 man job to lift it into place on it’s mounts – with the very stiff hydraulic hoses attached & filled with oil it’s absolutely unmanageable.
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Here the pump is being jostled into place. The central hole in the mounting plate is a very snug fit, if the pump doesn’t go in exactly straight it will jam & cause damage to both parts. The mating hole in the coupling hub can be seen here – it’s not quite lined up yet.
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We’ve got about 10mm to go before the pump is seated. It’s held in place with a pair of large studs & nuts.
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Here the pump is fitted enough to get the main mounting bolts into the coupling. These are torqued down to 150ft/lbs – a difficult thing to do considering the restricted space in the engine bay.
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The pump has been pulled down onto the plate evenly with the mounting studs, and is now completely flush with the plate. As can be seen, I didn’t bother tidying up the welds with a grinder, they aren’t in any visible place in normal operation, so it didn’t warrant the effort.
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Finally, the control cable is reattached to the pump’s control lever & everything is installed! A short test trip proved that everything was stable & no undue movement of the pump or coupling was noticed.
Until next time, 73s!