Arsebiscuits!! Here we go again, another chapter

[Fanum]

I've spent the last couple of weeks going to work on the bike, and although it hasn't been running properly, it's been running well enough to use since I had the injectors cleaned.

It's been hard to start, feeling like the battery was dead, so this week I put a brand new Exide in it.

It's been pulling off in 1st and second OK, but when it gets to about 4k revs, it started fluffing and felt like the fuelling was fekked up still....supply or something.

Oddly though, If I went to about 6500 revs then changed up, as long as I could drop into about 5000 revs in the next gear, it would carry on picking up...full power (or nearly full anyway) available

So for the last two weeks I've been looking for a fuelling issue.

I changed the filter for a nice shiny billet thing that I can take apart and clean, I changed the hoses for new braided ones, I had the pump out of the tank yesterday and found that the very short link pipe between the outlet of the pump and the metal pipe was showing clear signs of Ballooning.

I took it off, and sure enough, that bit of pipe was a non-reinforced type , and the middle of it had gone very flexible and squidgy, as if it had been blown up like a balloon many times.

So, having replaced that with some proper reinforced tube, and replacing the loop of tube where the internal filter used to live (mine lives outside the tank) I investigated the wiring to the 4 pin connection.

It's been totally bodged about at some point (not by me) so I cut it all back, took put the 4 pin connector and replaced that with two waterproof two pin Durite connectors arraned M>F and F>M so they cant be mixed up

When I put it all back together, it was exrtremely slow turning over, sounded like it was really struggling, even with the brand new battery on it, and then with double battery landrover jump pack on it, same result.......so out came the starter motor.

Looked ok, no smell of burning, wiring OK, so after a good clean up, I refitted it.

Earth connection?

Looked ok, but just in case, I ran a new 80 amp wire from battery neg to starter casing mounting bolt for a good new earth....

Turned over slightly better with jump pack but still struggling, and suddenly fired up and revved sweetly.

Thinking I'd finally solved the long running mystery, I set off for home a bit later.......and for ten minutes had a huge grin on my face........revved sweetly and pulled nicely through all gears to top, no spluttering, perfect!!

Then, it started coughing a bit, and within a hundred yards, was firing on only one cyl again, then died completely.

Called the AA, and with his jump pack, it barely turned over, so waited around for another couple of hours for a recovery truck and it's sat outside , dead again

Question....is it possible for an engine to partially seize?

I'm losing the will to carry on now

Thoughts welcome, but be gentle please

 

[Magwych]

Battery positive cable ? Any sgns of corrosion on the connectors at the ends? I believe the early 1200s had issues with corrosion where the positive cable attaches to the starter.

It seems replacing the neg battery cable helped a bit, and the problem seemed to actually worsen when another battery was fitted.

 

[Fanum]

Battery positive cable ? Any sgns of corrosion on the connectors at the ends? I believe the early 1200s had issues with corrosion where the positive cable attaches to the starter.

It seems replacing the neg battery cable helped a bit, and the problem seemed to actually worsen when another battery was fitted.

It looks ok, and the jump boxes were all put directly onto the live terminal on the starter anyway*, so I can't see it's that

Thanks though Martin

* to be accurate, in the workshop I went to the starter terminal, then on the way home the AA man's jump box was to the live terminal stud that screws drekkly to a bracket off the same terminal.......IE bypassing the bike's battery altogether.





There's something SERIOUSLY wrong in there......unless the starter itself (and fingers crossed on that) is fubared and turning lazily, it feels like the engine is tight and gets worse when warm.

It still turns over, but so sluggishly i thought the previous battery was dead



The starter wasn't anything to do with the breakdown on the way home though, so I've got a nasty nasty feeling that the engine is Fekked again

 

[SOOTY]

Have you tried turning the engine over manually,you know spanner or socket on the crank pully.It may give you some idea of how the engine feels.

 

[Fanum]

Have you tried turning the engine over manually,you know spanner or socket on the crank pully.It may give you a clue.

No, but it's on the list to do ......When it came off the back of the AA truck a few hours ago, all I wanted to do was crush something and have a drink

It did wheel around ok in gear though, thinking about it.

 

[ahutcheon]

My guess would be that the breakdown is something semi-trivial going wrong with your last fix, has anything happened to the new connectors or bits of tube? Some crap from the new tube lodged in the feed to an injector?

And that the starter issue is a separate problem - if it's not the wiring, it wouldn't be the first BMW starter to go faulty (is it only airhead ones that have the magnets come loose)?

Partial seizure doesn't sound likely to me: the engine makes much more power than the starter, and the bike idled but didn't rev out properly?

A couple or several different things, some of them possibly intermittent, combining to confound diagnosis? Good luck!

 

[(RIP) Kaister]

i had a similar thing on the 1100 - put a new battery in - same - used a jump off the car - same.

took the starter out and dismantled it and found the magnets had come unglued and were wedged on top of each other.

i think i used a vauxhall nova / holden barina rear section of starter motor - much cheaper in Aus.

i even phoned neil at 11 at night and woke him up

 

[Fanum]

I'm going to keep my fingers crossed for the rest of the weekend that you're right, and that the two problems are unrelated.

I took a lot of time going over the fuel pump, the wiring to and from it, the replacement of the pipes and all of the connections on them.......The tank respray is crap though, and there was a lot of soggy rubbery paint around the filler neck......I cleaned up as much as I could, but there is a possibility that a large chunk of the red soggy rubbery paint has blocked the pump sock up again (I used the original sock after cleaning it and checking its condition)

The only part of the fuel system I haven't had apart is the pressure regulator, which I have a feeling lives under/in front of the ABS unit.......I Wasn't going to start taking that fekker out

So....I guess that could be a culprit (oddly though, I can't even see one on the OEM parts list but I had one out of a standard 1150GS last week) if it's blocked up with paint detritus.

So, assuming the new connections in the fuel tank multi plug(s) may have gone tits up in that ten minute ride or it's the pressure regulator that's blocked, and assuming the starter motor is fekked, I might be ok

If not,

 

[STUBBS]

fingers crossed for you, its certainly putting you through it

 

[bowser]

I had a similar problem with my bike, it would start and run and seemed fine as soon as you put it under load it bogged down and would not pull or red and just died. All I had done was take the tank off and put it to one side whilst I did a clutch and put it back on, go figure.
That was a problem with the filter or pump, I have a spare tank with internals and put it on the thing worked fine.

I suspect you are right about the statrer motor, my wife bike was running fine we went for a ride and stoped a the ace for a tea and all of a sudden it wouldnt start, we managed to bump it and get home, it a real easy check, just undo two bolts and take it out and try turning the gear with you fingers you can tell if its got a problem or not.

 

[Fanum]

, it a real easy check, just undo two bolts and take it out and try turning the gear with you fingers you can tell if its got a problem or not.

Did that this afternoon......the gear felt stiff to me, but I had nothing to compare it to other than a car starter motor which felt about the same TBH.

It turned, but not smoothly or easily.....on the finger-torque scale, it was stiffer than a pinky but turnable with an index finger IYSWIM.

I don't know how easily they're supposed to turn though

The other end, under the cap, looked all nice and clean though, and there was no burnt smells from it.....I gave it a good squirt of brake cleaner and stuck it back in, but as they are so easy to swap around, I'll probably pinch Gert's starter motor next week on a quick swap basis to see if that makes a difference

 

[Uncle Rob]

The only part of the fuel system I haven't had apart is the pressure regulator, which I have a feeling lives under/in front of the ABS unit.......I Wasn't going to start taking that fekker out

its under the air box

 

[Scuba-Sparky]

Hi Fanum
Had a similar starting problem on my mate 1150 a few years back. Pulled the starter motor apart and there is a metal dust shield at the drive end that had come adrift and was shorting out the windings, so I removed it. It was sorted properly when we got back home a few days later.

Hope it helps.

Scuba

 

[Fanum]

Hi Fanum
Had a similar starting problem on my mate 1150 a few years back. Pulled the starter motor apart and there is a metal dust shield at the drive end that had come adrift and was shorting out the windings, so I removed it. It was sorted properly when we got back home a few days later.

Hope it helps.

Scuba

TY

The starter looks ok, but obviously isn't, even after a good clean up, so I'm going to swap it over on a temporary basis with another GS starter as soon as I get back in to work, then assuming that works bettter, I'm just going to swallow it and get a new unit i think.

This one is the original AFAIK and it's got a fair few miles on it.

 

[bowser]

It should turn very smoothly, and without much effort

Did that this afternoon......the gear felt stiff to me, but I had nothing to compare it to other than a car starter motor which felt about the same TBH.

It turned, but not smoothly or easily.....on the finger-torque scale, it was stiffer than a pinky but turnable with an index finger IYSWIM.

I don't know how easily they're supposed to turn though

The other end, under the cap, looked all nice and clean though, and there was no burnt smells from it.....I gave it a good squirt of brake cleaner and stuck it back in, but as they are so easy to swap around, I'll probably pinch Gert's starter motor next week on a quick swap basis to see if that makes a difference

 

[argos]

If its any use Im in Stratford E7,welcome to borrow starter,pressure regulator,coil,HTs etc for diagnostic purposes,Cheers

 

[Sir James]

Many years ago i had a K100 for despatching on and had a white paint job applied by a fool who filled the tank with over spray as he said it wouldn't harm it .......

Iv'e forgotten how many times i changed and cleaned the fuel filter as it would run for 10 to 15 minutes then die , removal of fuel filter and a quick roadside blow would surffice and pump would run smoothly ..........

I part exchanged it due to high milage and an unbeleivable deal from BMW , i did learn later that the whole fuel system was removed ,cleaned and over hauled and a new tank fitted ...............

 

[Fanum]

Well, the new starter motor is on and helping immensely, but the fekker is back to running on one cylinder again.

The breakdown the other day was because one of the new pipes I'd put on that goes between the two spigots where the internal filter used to be mounted had blown off, but I put a new bit in, new jubillees and just to make sure, a steel spring around the 'u' bend so that it doesn't kink flat rather than follow the 'U' shape it's bent in in a small radius.

It ran fine for another ten minutes, then conked back to one cylinder yet again

The external fuel filter (below) is clean (you can take it apart completely and wash the little brass filter in it), the new braided fuel pipe is all unkinked.

Tomorrow I'm going to ride it into the shed again on one cylinder and take out/clean the system through one more time, including the only bit that hasn't been out yet, the pressure regulator/splitter under the airbox.

 

[AberdeenAngus]

the only bit that hasn't been out yet, the pressure regulator/splitter under the airbox.

Its probably that then

 

[MikeP]

It ran fine for another ten minutes, then conked back to one cylinder yet again

Bill,

When you say that it ran fine for ten minutes, was that riding it (ie mixed throttle openings) or just left running at a fast idle?

Without going back through all of the threads on the problem, when were the throttle cables last replaced?

I ask as when a mate was running an 1100GS, he had something similar; the bike would run on two cylinders and then drop to one. It was as though the cable wasn't seated correctly at the throttle-end (you know the photo well).

Yet whenever they were checked, both were seat correctly. In fact what was happening is that one cable had frayed inside the outer sleeve. It would stick and throw the balance right-out.

I found out by feeling for the slack in the exposed section of the cable (with the throttle closed) between the adjuster and the quadrant-guide.

Try opening the quadrants with your delicate little fingers and check that they both snap-shut repeatedly against the stops.