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Hello

TLDR: whats the correct sequence to bleed the brakes? Rear first, front and how do you bleed the footbrake?

I picked this MP3 400LT a couple of weeks ago as a winter project with the aim of completing an Ironbutt on 3 wheels later this year (1000 miles in 24hrs!)

I've had to replace one of the forks and thus undone the brake lines on the front. I read how difficult bleeding these can be so was prepared for a fight. I reverse bled the brakes and tied up the lever and left over night. The lever was nice and firm and the brakes worked well... but the lever is still too soft to pass an MOT (I'm in the UK) as it reaches the bars.

The garage that inspected it said they could have a go at bleeding the brakes so I agreed. They've made it much worse and tell me something must be broken! The must have flushed 2 litres thought the system trying to bleed it using a mityvac.

As I only messed with the front I didn't touch the rear brake as it felt good.

Question 1: Could air be trapped in the rear line or footbrake be making the front brakes soft?

Question 2: Have since taken off the rear calliper (what a pain!) and one of the pistons was ceased - would that cause this issue?

The bleed nipple was broken off so I've purchased a brand new rear calliper and was planning to reverse bleed the system from the rear first.

Question 3: How does the footbrake work with the front/rear? I know they are combined and if you push the footbrake you can feel the pressure or rear lever on the handlebars move. Is this normal and is it bled through the combined link under the windscreen?

Any help would be appreciated as I'm going nuts!
My MP3 400ie LT
My MP3 400ie LT
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Thanks flybynight! I've been using a 400ie workshop manual so didn't have the pages for the LT, doh! I suspected there would be a specific sequence.

The procedure is on page 312 of the LT workshop manual

1. Bleed rear brake in the normal way - through left hand lever topping up the reservoir.

2. Bleed front brake to the combined brake unit bleed nipple under the front cover (not the callipers!) topping up through the reservoir.

(now the important bit!)

3. Bleed the front brakes (left calliper first) using the footbrake topping up the footbrake reservoir.

4. Bleed the rear brake through the footbrake topping up the footbrake reservoir.

Its 11pm here and -4c in the garage so will try again tomorrow using the above.

Thanks

Carl
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All thanks going to uploaders of the manuals, glad it helped.
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To update. Used the method as per the workshop manual but no luck. Rear and foot brake feel decent and the front is miles better but I think still has too much travel to pass an mot. I must have pushed 1.5l of dot4 through the system!

Have booked it in at a Piaggio dealer in London next week for them to have a go.

Have tied back the levers but does anyone know if it's worth pushing the foot brake down over night? With the rear lever (and new rear caliper) feeling good I'm thinking the air must be stuck in the combined braking pipe between the footbrake and right lever.

No bubbles are coming out of any of the bleed nipples.

Also noticed the oil breather pipe is split so will have to order a new one from Fowlers. My cheap commuter is starting to get expensive!
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Well it passed its MOT today without any advisories. My bleeding of the brakes was good enough.

What wasn't good enough is that it refused to start after the test and is now stranded at the MOT centre. I'm on a very long train ride home.

The immobiliser is stuck on. Any ideas?

Starting to think the mp3 was a bad idea Facepalm emoticon
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Hi Carl400LT

User PabloLie had similar issues recently that are discussed in this thread. Some diagnostics such as indicator lights on the dash-board, engine behavior (does it start? rev?) are all critical to figure out what the issue could be.

All of a sudden... 2019 MP3 does not start

Some callouts that often come up with the immobilizer
* Battery voltage
* Transponder and Key system around the ignition
* Physical circuit fault with one of the safety sensors (seat, kickstand, etc)
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Hello

Thanks for the reply. No it didn't start. The fuel pump primes, then the immobiliser light flashes 3 times before going solid red indicating a key read fault. The engine management light stays on and blinks once.

The garage said it could be the antenna that's in the ignition that reads the key. They've seen that before. Given the amount of brake fluid that spilled when bleeding the brakes it could be. It was all washed off but maybe something became loose or damaged with all the messing about.

Its annoying that it so far away as I'd like to try the other key before shelling out on new parts (they currently have the brown key).

I left it with them so I'm sure I'll find out next week how big the bill will be. Looks like a new antenna is about £170 for the part alone. If it's the throttle body/ecu I'm not sure what I'll do as that's pretty much what I paid for the bike!
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For anyone with similar problems. The garage diagnosed a faulty immobiliser antenna.

Looking at about 400 for them to fix it.
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It's MOT'd and was working great until it decided not to start. With thanks to the poster I quoted in the other thread it's working again.

Need help as my MP3 wont turn over.

This has been a journey. I said to the wife I fancied a winter project but not sure I wanted this much of a project!

For anyone who is interested. I still plan on doing an Ironbutt from Lands End to John O'Groats in less than 24hrs on it when the weather is better.

For posterity here is what I've done to the bike to get it through it's MOT and rideable again.

Replaced:

* Front right fork
* Front right speed sensor
* Bled brakes (10 times lol)
* Both brake light switches
* Rear brake caliper and pads
* Immobiliser antenna *done by garage as I couldn't get it home*
* Indicator switch as it was sticking
* Tilt lock switch as it was broken
* Airbox screws
* Random bodywork screws

To fix this week's starting issue I've also bought but not fitted:

* Starter switch
* Kill switch
* Yellow under seat relay

I've glued the broken plastics so it all went back together.

I bought the bike with minor front end damage so was expecting to replace some bits but didn't expect so many. What attracted me to this bike was it had recently had over £1000 spent on it at a main dealer before it was damaged. It's had:

* 3 new tyres
* 2 new rear shocks
* New pads and discs all around (the new rear caliper came with pads so I have a spare set.
* It has been serviced, so oil, plug and air filter
* headstock bearing
* New clutch pads and belt

It's a good job I picked it up cheap but I've now spent as much on parts as I did for the bike.

It needs to pay for itself now so I'm going to keep it for commuting duties. To be honest I don't really have that much trust in it even though it's got so many new OEM parts!
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Sorry to hear about the troubles, but you do realize it is Italian right?

The Italians may have invented electricity, but they mastered the art of electrical malfunction.

Case in point, 100 years ago when the Titanic struck an iceberg in the middle of the ocean the lights stayed on until the very end. 10 Years ago, when the Italian built Costa Concordia hit a rock a couple hundred yards offshore the first thing that happened was a instant and total blackout.

Coincidence? Me thinks not.

If you're looking for the finest cuisine in the world, nothing beats the Italians. On the other hand, if you're looking for the most dependable vehicle (2 wheels or 4 wheels) nothing beats Made in Japan.
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Well it's let me down again. I'm currently stranded in central London waiting for the recovery truck. Worse places to get stuck but hey ho.

It lost power at a set of traffic lights and won't start. Tilt lock alarm won't stop when ignition is on. Seems like the brand new battery is flat which means the stator or regulator isn't working as it should.

Depending on the diagnoses I think project mp3 might be heading for the bin. Not sure I want to keep spending money on it.
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How often do you use it? due to all the background electrics even when switched off and not in use, you really need to keep it on a battery optimiser especially if you only do short journeys.
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It gets used a couple of times a week. Used it for a 30 mile trip on Saturday and it's been on an optimate since.

The battery is a Yuasa ytx 14 bs so not a cheapie off Ebay and I don't have any mods that would drain the battery.

AA were decent and arrived within an hour. He charged the battery for 10 mins then followed me to the garage that did the MOT and replaced the immobiliser antenna last month. It's now with them to diagnose.

The guy at the garage said its and engine out job to replace the stator so really hope it's not that and the battery is dead or the rectifier has gone.
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It sounds like the bike has become a "cost to fix" vs "cost to replace" situation.

Your in a "sunk cost" fallacy having already spent significant time, energy, and money fixing things doing that "one more" is becoming a real question. You've already replaced allot of components including the expensive immobilizer which makes ditching the bike hard to justify. Ditching it means all the other investments are waisted leaving you without a machine to enjoy.

I would recommend the following. Do the stator and battery charging tests to see if the battery charging system is working or not before taking any plastic off. Presuming its isolated to be a bad stator then do the stator replacement if the cost is reasonable and you can afford it. Otherwise if the stator tests good and the charging system is good....then it becomes a parts bike that other Mp3s might live and you recover some of the sunk costs.

It can be hard to justify fixing a wonky Mp3. The bikes are expensive to maintain with few mechanics working on them. But at least around my area, these have allot of "fun" factor going for them being quirky and unusual. Lots of folks wave, some approach to task about it, cars will keep pace with me on the road so the kids in the backseat can wave. The smiles it brings makes it worth it when compared to more efficient or reliable Honda motorcycles. That and the 2 front wheels has saved me from dropping the front end when I hit slippery paint, sand, gravel, and wet roads that had a spot of black-ice.

Only you can make the decision that lets you sleep comfortably.
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Someone recently with a Vespa found that their aftermarket key only worked one way up. If the key was inserted upside down, the immobiliser wouldn't deactivate. Might be worth trying this if it stops again? Or trying the spare key if you have that?

As for the iron butt, will this be your first one? How are you planning to attack it in terms of rest and sleep, and do you have a route planned?
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Thanks for the suggestion. I had a chance to pop into London on Saturday and have a look at the bike myself. I wanted to check the obvious stuff that I couldn't do at the side of the road without tools especially the 'hidden fuse' on the starter relay. Found some very helpful pointers in this thread:

Hidden Fuse DONE - pictures and all

I had starting issues last week which I put down to dirty contacts on the yellow relay under the seat. It's been fine since cleaning them with electrical cleaner.

Having read the above thread I wanted to check the 30A relay fuse because I didn't disconnect the battery when cleaning that yellow relay. Maybe I'd popped the fuse and the battery died on the way to work?

This is what I found... No luck it just been a blown fuse.

So that is goosed, but what I couldn't do was replace it as the holder in the relay was burned to a crisp.

I pulled the stator wires and whilst there was resistance as per the service manual I didn't get a chance to properly test for voltage as the shop was closing soon. When it's all plugged and with a fresh battery the battery is getting no charge but I think that's due to the starter relay fuse.

So rather than risk it braking down on the way home I've left it with the garage for them to properly diagnose. Looks like I'm in for a new starter relay at a minimum and/or stator. If it's just the starter relay what on earth caused it to go bad?

Will update this thread when I hear from them.

The saga continues...
30a starter relay fuse
30a starter relay fuse
Burned starter relay fuse holder
Burned starter relay fuse holder
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See: https://www.wotmeworry.org.uk/fuoco_solenoid/ for some pictures of the corrosion that WILL happen with the original starter relay, as it's in just the right position to get all sorts of muckite thrown up at it.

The newer relays are better, but still need a good smear of dielectric grease (Vaseline will do fine) all in and around the contacts.
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I picked the scooter up on Thursday evening and after parting with £108 got home OK. Was an exiting ride home, in the dark on the motorway..

The guy at the garage said there was no obvious reason so I'm assuming that it was dirt or corrosion on the contacts that caused it to let go. They've done a decent job cleaning the contacts etc.

Does anyone know if this is an early warning to something more serious on its way out like the stator or rectifier? I've had my multi meter out and I'm getting 13v plus at the battery when it's running. I think I'd like to shift the bike on now whilst it's working that wait for a major fault.

Hope people don't mind me documenting my journey here.

Thanks for all your help.
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So to finish up my journey... My MP3 was running fine, cleaned up well, but I decided to sell up and it has a new home.

Whilst the MP3 is a fine scooter I think I was expecting too much from a 15 year old example with the type of riding I do.

I had fun fixing it up and getting it through the MOT, I experienced what its like to brake down (fun! not), learnt loads about 3 wheels Piaggio scooters via this forum and youtube and had some fun rides out.

Thanks for all the help posted in this thread.

Happy and safe riding all!
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Glad the forum was able to be of service to help get the Mp3 running again.

Thank you for sharing the story and journey getting the Mp3 running. These forums are forever so someone somewhere will find this thread and use it to fix their own MP3. I wonder if the new owner will show up on this forum later

Safe riding and happy miles friend

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