Stuck bolts removing the Alternator

[AustinW]

2011 R1200 GSA. 86,000 and a bit scruffy with lots of corrosion on the engine under the tank, in fact a bit scruffy everywhere.

I left the bike in the garage for 10 weeks while we explored down under in a camper van and came back to it with what I am 99% sure is a seized alternator.

I started dismantling today. Tank off and alternator cover off, easy peasy (done both before). I cut the alternator belt as the engine wouldn't turn to use a bit of plastic to slide it off. With the alternator disconnected the engine turns just fine. A quick peruse of the Haynes manual says remove the four bolts that hold the plastic alternator cover on. T25 headed bolts to the top of the front engine cover. This where it all went wrong.

First bolt was very tight but came out OK with a bit of squeaking despite a squirt of releasing oil, next bolt turned about a quarter turn and got tighter (corrosion) before I felt the torx head give a bit - sure enough swarf on the bit which was a very loose fit after that. Despite mucho trying, hammering the bit in and being very careful I couldnt get it to let go and the torx head is now a bit mashed. All three bolts were liberally doused in penetrating oil and left for an hour or so. The third bolt let go at first, then went tight before snapping (I was using the bit in a screwdriver for chrissakes). So now there's a snapped stud to deal with too. The fourth bolt released about a sixteenth of turn, went tight so I left it all and had a couple of beers.

I am inclined to give up and take it to a professional (Mikeyboy I reckon) as there's a few other jobs that need doing requiring more skill and tools than I have. While I make my mind up any thoughts on removing the remaining two bolts and any other insights on alternator removal. Like do i have to remove the front shock or is there enough room to wiggle the alternator out.

(I am also minded to shove the bloody thing to the back of the garage and go out and get a new Guzzi 85TT. Its about the best looking bike I have ever seen).

 

[Bendy toy]

As you already have one seized bolt you might as well talk to Mike as that's likely to be beyond most of us mere mortals.

With Torx screws it's all too easy to use the next size down which will seem to fit until it mashes the screw head. Always confirm the next size up will NOT fit before using the bit. But it sounds like the bolt heads were not your problem.

Bolts that have seized solid can often be shifted only with heat. Arc weld onto the bolt head puts powerful heat right at the point of need. Lots of spark protection mats are needed around the job.

BUT and its a BIG BUT - any connected electronics are likely to get toasted by all the voltage spikes so make sure ALL boxes are not just powered down but disconnected. On the GS that's a lot of connectors - Battery, ABS, ECUs, Alarm, instruments, alternator, etc. At least you aren't bothered about the last one.

You will need to remove one of the front subframe / head bracket side arms then the alternator comes out ok. Its fiddly though and more bolts to be seized up.

There are two alternators. The GS has a larger pulley and longer belt. The GSA (higher power alternator) has smaller pulley and shorter belt. The drive pulley retaining bolt is wound up very tight. My alternator was seized so I wasn't concerned about damaging it but gave up trying to remove the drive pulley.

 

[AustinW]

Thanks Bendy. I have pm’d mike about it together with asking for his thoughts on giving the bike a bit of a refurb. The rear sub frame is very rusty and most of the paint is peeling off the engine. Wheels scruffy as is just about anywhere else on the bike that’s painted. It’s very disappointing really as although the bike has done 86,000 miles it’s not had a lot of winter /salty use.

Perhaps it’s time to change. The 1250 Rallye or the Guzzi V85TT are very tempting.

 

[landmarkjohn]

Just my 2c on applying heat..... took out a hex head shock bottom bolt with an electric impact gun (from LIDL, best thing ever!) and heat. It wouldn’t budge at first but then applied heat with a variable heat gun dialled up to 260 C and it shifted it, no paint damage.

 

[AustinW]

The bolts to be removed are Torx T25 cap head bolts that hold the shroud onto the alternator. Access isn’t straight due to the telelever and I have rounded the internal star in the cap head. The two remaining bolts have turned about half a turn before going so tight again I rounded them despite applying plenty of releasing fluid. I can’t get mole grips or anything onto the cap heads - least not so they grip tight enough to turn them. I have also tried tightening to clean the thread a bit but again I can’t get enough friction to turn them in either direction. The bike is booked into RGM motorcycles for him to play with but he is maxxed out until nearly the end of June. I am sure he will have the bolts out in minutes.

In the meantime I have sourced a used alternator from Sherlock’s and have given the rear sub frame a good de-rusting and s thick layer of black paint. Next job is the tyre pressure sensors and an oil service.

 

[Bendy toy]

It's probably easiest to get the Telelever swing arm off and out of the way. That makes removing the front subframe much easier so you might want to consider a new head bearing. They do wear though not as fast as "normal" forked bikes.

Really stuck bolts can shear off all too easily so some arc weld onto the bolt head can deliver enough thermal shock ti shift it. As said previously that's a pain because ALL electronics must be disconnected to protect from welding voltage spikes.

On the 1970's Suzuki, I had all tin ware grit blasted and zinc metal sprayed. For protection, it's second only to hot dipped galvanised. A careful flatting to remove metal spray nibs flowed by a good etch primer then a normal primer and paint. It's a faff but you'll only do it the once.

 

[Bendy toy]

I should have added that metal spray malarkey is for the frame components not the alternator bolts.

When rebuilding use a good quality anti seize grease. I have found Action Can CS-90 is good stuff use it all the way up the bolt shank to avoid small areas of contact that can increase the galvanic effect.