Newbie question - suspect seized alternator

[cornwolf]

Hi all

I'm back to biking after a break of over 30 years and chose a '98 ST1100 for my ride, I wasn't sure if I could still hack it so I bought a cheap, high mileage example (122k).
I am (NOW) aware of most of the Pan's foybles, it's been off the road for the last 3 or 4 weeks whilst I searched for some new silencers/mufflers (now fitted) now I come to start it and guess what? it won't turn over, I've put the battery on charge just in case but, knowing my luck, I am prepared for the seized alternator syndrome I've heard so much about

My questions are: where is the alternator? is there a way of testing before I take it to bits? can I turn the wheel on the centre stand in 5th gear?
If it helps - the bike is high mileage and was used every day by a courier, now I've brought it to live by the sea and only use it occasionally, the last time I started it up was about 3 weeks ago, can the alternator seize in this short space of time?

Thanks in anticipation

 

[Mr. BR]

The alternator is on the back of engine, left side, down low, behind the gear-shift lever. Remove the gray plastic panel behind the gear shift lever and you'll see the alternator unit. I don't know if I'd say the seized alt is all that common but it does seem to appear on bikes used year round on salted roads.... and/or perhaps then left outside for extended periods of time after the corrosion has already started. Is 3-4 wks enough time.... not sure but I'm guessing it's certainly possible depending on the conditions. In the meantime, get your battery fully charged and with engine running, check your running DC voltaged with a digital voltmeter on the battery. Check the easy stuff before assuming the worst.
Regards,
Mr. BR

 

[cornwolf]

UPDATE - Re: Newbie question - suspect seized alternator

Thanks for that, update - I stripped off the panels and can see the alternator, fitted a new battery just in case (only ?38). If I 'flick' the starter, relay clicks, starter kicks in, I can see the alternator armature move a couple of mm then the engine gets 'tight' starter apperars to struggle and 'squeal' slightly (almost like a high pitched whistle) then stops, if lights are on they dim right down but don't fade out like if the battery is flat, I can do this dozens of times and she continues to try and turn, one other thing - I tried to bump start (very difficult on a very slight incline as you can imagine) in 3rd/4th gear and she stops dead so this makes me fear for the engine now, does anyone think it could be the engine or the starter/clutch, is there an easy way to check?
She ran fine a few weeks ago on a 90 mile run???

Thanks aginn

 

[Mr. BR]

Re: UPDATE - Re: Newbie question - suspect seized alternator

Time to dig a little further to see if your engine is locked up via the alternator or something else. Pull spark plugs perhaps, turn engine over by hand carefully. Have it in 5th gear and turn rear wheel or better yet use the nut on the end of the crankshaft (front of engine, remove small access cover below radiator). You need to find what is holding up the engine before further attempts with the starter motor or bump starting....
Mr. BR

 

[jim'll break it]

I have had the same problem with mine, remove the tank, slacken the three bolts retaining the alternator, pull it back off its splines, then thumb the starter, if the engine turns over then the alternators shot,
remove the swingarm and take it out, then repair it or fit a replacement,
a good sign of corrosion is a cracked alternator body so if you see cracks its definetly worth pulling it to see

 

[cornwolf]

Update.... thanks guys, just had it all apart and it was the alternator, unfortunately whilst in there it was discovered that the swing-arm was toast also (guess the seller saw me comin'), now got myself a 2000 ex-Avon and Somerset Plod Pan with 54k on the clock, think I'm going to break the other one so if anyone needs any bits I'm keen to get some of my ?1200 back :-(

 

[cornwolf]

now go grab that southern region tag while the weathers still nice.

Not so fast Trosty.... being the wrong side of half a century and very few miles since I 'gave up biking' in 1979 I'm not nieve enough to think I can just jump on and go so.... signed up for a back-to-biking course next week, I like to think I'm being sensible but really 'er indoors would only let me loose on a bike if I signed up lol

 

[thunderpipes]

Update.... thanks guys, just had it all apart and it was the alternator, unfortunately whilst in there it was discovered that the swing-arm was toast also (guess the seller saw me comin'), now got myself a 2000 ex-Avon and Somerset Plod Pan with 54k on the clock, think I'm going to break the other one so if anyone needs any bits I'm keen to get some of my ?1200 back :-(

I had exact same thing happen to mine at 20years 80,000miles.due to split alternator, caused by UK road salt & rear mudguard being too short and allowing mud & road salt in to enter the alternator. Eventually this will make the outer casing swell & crack it.This will lock the engine solid. I brought a Chinese copy alternator from USA, this cost £135+£35 import duty & and post. It arrived about 2weeks latter and looked & worked just like the original. Spray WD40 on all nuts & bolts before attempting to undo anything. I repainted the parts that are prone to rust and cause Mot failure. We paint the £800 swing arm,the underside of the fuel tank, £300 rear shock & rusty bits of frame near by with Por15 paint(£22)its very durable but you only get a small tin that goes a long way. This is brilliant brush on paint. Don't get it on your hands. One week latter my hands are still black, be warned this is special paint. Look on fleebay for the paint, alternator & tools. Dog in to it.its only nuts and bolts. You have nothing to lose, your bike is dead, you have everything to gain. Don't be frightened, it's your hobby remember. Use this forum, a Haynes manual & watch YouTube vids and take pics with your camera phone to help you remember where things go. You will need the swing arm removal tools this is a castle type socket & you will need a 17mm hex to undo the other side fitted to a long-bar, this was very tight. again on ebay. By the time the alt arrives from USA you will have completed removal & painting.leaving you the more enjoyable reassembly. I had time to extend the rear mudguard with plastic & fixed with 3 bolts.i am not a mechanic and I had all the parts to hand. It took two days to do. I had to borough some tools from a friend. I hope that this will inspire owners with this problem. It's not the end of the bike. If I can do it, You can do it.

 

[thunderpipes]

The alternator is on the back of engine, left side, down low, behind the gear-shift lever. Remove the gray plastic panel behind the gear shift lever and you'll see the alternator unit. I don't know if I'd say the seized alt is all that common but it does seem to appear on bikes used year round on salted roads.... and/or perhaps then left outside for extended periods of time after the corrosion has already started. Is 3-4 wks enough time.... not sure but I'm guessing it's certainly possible depending on the conditions. In the meantime, get your battery fully charged and with engine running, check your running DC voltaged with a digital voltmeter on the battery. Check the easy stuff before assuming the worst.
Regards,
Mr. BR

Try to rotate the engine by removing the front inspection cover 2 10mm bolts & remove all the spark plugs.

 

[thunderpipes]

Try to rotate the engine by removing the front inspection cover 2 10mm bolts & remove all the spark plugs.

If it don't turn it's probably a seized alternator.this happened to mine . The rear mudguard is too short and everything drops into the alternator. So add
a bit of plastic and drill and bolt it together.

 

[thunderpipes]

I have had the same problem with mine, remove the tank, slacken the three bolts retaining the alternator, pull it back off its splines, then thumb the starter, if the engine turns over then the alternators shot,
remove the swingarm and take it out, then repair it or fit a replacement,
a good sign of corrosion is a cracked alternator body so if you see cracks its definetly worth pulling it to see

there's a Chinese alternator at a fraction of the price but you have to order it from the USA to dodge the copy rights

 

[Bmacleod]

thunderpipes, all this info is good and relevant, but be aware, the OP hasnt been around in 9 years