Replacement fuel pump bracket swap pt2

[3-Max]

Hello again. So the nitty gritty: All the necessary work goes on at the in/outlet end.
REMEMBER to TAKE PHOTOs as you go you may well need them to align the pipe holes to the diaphragm block.

1st. Undo the five retaining screws that hold on the in/outlet pipe plate & pull it off (both pumps). It will look like this on the inside.


I swapped over the new gasket for the old gasket on the old pipe plate.
The black plastic diaphragm block will now come off (see last pictures from pt 1). I kept the new one on the new pump so I'd be using the new diaphragms.

Next, undo the three screws that hold the mounting bracket to the pump body. Note there also 2 nubs & holes stamped in these flanges. Slide the mounting plate across as far as it will go. It will now look a bit like this (old pump):


(The bracket is on upside down as I took these pics while practicing how to do this & this is attempt 3.)

Where the bracket plate is farthest from the centre, pinch the main diaphragm and push it through the hole. If you can push the plate up a little this helps greatly. It will look something like this:


Lift the bracket plate & slide it all the way across and off the pump:


Repeat for the other pump.

I noticed that the gasket under the bracket plate felt gritty in the new pump (the red/brown one in the pictures). I took it off & wiped it. I also wiped under the main diaphragm with some paper towel. Good job too as there was a noticeable amount fine metal swarf. I'd recommend a good spray with WD40 or contact cleaner too.


I also noticed a burr on one of the nub holes on the new pump body flange. Took that out with a needle file.


Putting the bracket plate back on is similar. Lift & push the main diaphragm through the bracket plate hole then pull more of it through as you push the plate across. It gets a little awkward for the last little bit but the diaphragm is strong enough as long as you don't go berserk. The diaphragm on the old Mitsubishi pump is decidedly thicker in the middle than the new one so a little harder to manipulate (these are me practicing on the new pump):


Make sure you put the old bracket on the new pump & align the nubs & holes - there are 2 nubs & 3 holes. Doesn't seem to matter which combo you use so set this how you want. Screw back in place with the 3 screws.

Replace the black plastic diaphragm block & fit the pipe plate. Make sure you get the block the right way up. This assembly can be rotated so that you can have the pipes oriented to the connector lead / mounting bracket any way you like. I followed the original layout. Also make sure that the in/outlet holes fit over the correct chambers in the diaphragm block. Hope you took some pictures - I didn't but I did refer to the impressions left on the old pump's pipe plate gasket. Fasten the 5 retaining screws & you're done.

There may be errors, I always have to proof read multiple times & often miss things but that looks right at the moment. (Ed.: corrections made)
Happy pumping.

 

[DirtieGirtie]

You're scaring me... When I turn my black Vmax to the 'on' position, but before starting her up, I can hear click-click-click---click---click. Is that a tell-tale sign of a fuel pump giving out on these bikes? My M109R fuel pump does the same thing, although it's faster clicks until the pressure builds.

 

[sdt354]

You're scaring me... When I turn my black Vmax to the 'on' position, but before starting her up, I can hear click-click-click---click---click. Is that a tell-tale sign of a fuel pump giving out on these bikes? My M109R fuel pump does the same thing, although it's faster clicks until the pressure builds.

Nope, ours click. But should stop when pressure is satisfied.

 

[3-Max]

You're scaring me...

I can only say from my limited experience.

1) I was already experiencing fuel flow problems (& still have carb / fuel mix problems). I could see there was feeble fuel flow through the fuel filter.

2) the points had already stuck together once & were charred black on inspection. I cleaned them up & it worked 'fine' afterwards, or so I thought.

3) there was no variation in the rate of clicking, start to finish.

It wasn't until I watched a Vmax ytube video that I got to hear another Vmax fuel pump, very rapid to start with then gradual decrease until it stopped. Much faster than my old pump so I thought I'd spend 20 quid to see if it made a difference. It made a noticeable difference & sounded like the one in the video.

If you're not experiencing any weak mixture problems, misfiring or lack of throttle response then I think you're fine.

You should also be able to hear the V Boost servo cycle the butterfly valves on when you turn-on the key/kill switch (for those who don't already know).

For context. I bought this trike in May. The previous owner had had it for 2 years. He'd done 42 miles on it in the 1st yr & none in the second. I'm amazed he'd done that much tbh as the rear end was, frankly, a death trap. I can only assume it was given some financial help in passing its MOT. I'd not started it in 3 months as I was rebuilding the swing arm so I could fit new shocks. The bike part has been seriously neglected in the past, clearly been stored outside in various stages of disassembly. The airbox didn't fit properly (perished rubber, sorted), the carb joint rubbers were perished, there's rust debris on the fuel filter paper & it has 2 needle valve jets dislodged & protruding into the intakes... & it still starts & runs ! (now that I've sorted the fuel pump).

 

[02GF74]

Nope, ours click. But should stop when pressure is satisfied.

The pump runs for around 5 seconds after the ignition is switched on and engine is not running. (a safety feature)