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Water In Gearbox And Other Problems


hrmad
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Don't beat yourself up over buying the bike with the bad seal. It would happen some time anyway so you would have had to learn sometime.

After 4 oil changes, all the previous water should have been out so it clearly has new water getting in.

If you decide to disassemble the clutch, be sure to keep track of the order of the plates for reinstall.

You can clean up the steel plates with some #400 abrasive paper on a flat surface and slide the plates on small circles to keep them flat.

I have had the fibers come unglued from the plates when water was in the oil for too long. They can also swell. If they seem OK, a light sanding the same way is OK.

I don't know about Beta but my old Gasgas had an index mark to get the pressure plate clocked to the clutch basket during reassembly.

Have fun!

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Thats_a_five: thanks. I'm starting with the water pump. I've got the housing off and have included a pic of what it looks like. Sorry but I couldn't get the circlip and impeller off. Does it look corroded? I know it's a bit silly to ask but I don't know what I'm looking for.

post-20468-0-39460800-1412009628_thumb.jpg

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The guts of the story seems to be... you cant prevent it and just repair or replace as necessary?

The longest repair was 5 years and it seemed to be related to the type and brands of coolant used. (ethylene verses propylene?) I noted the coolant used to get 5 years was Motul Motocool Factoryline Organic. Might be a good one to use if available??? More research maybe?

Don't forget to NOT mix coolant types or brands, a good flush is necessary. Look up Engine Ice and have a peek at their recommendations to flush system using plain vinegar and water.

This issue must have reared its ugly head here on TC? Try a search and see what comes up if you have not already?

Mags

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The guts of the story seems to be... you cant prevent it and just repair or replace as necessary?

The longest repair was 5 years and it seemed to be related to the type and brands of coolant used. (ethylene verses propylene?) I noted the coolant used to get 5 years was Motul Motocool Factoryline Organic. Might be a good one to use if available??? More research maybe?

Don't forget to NOT mix coolant types or brands, a good flush is necessary. Look up Engine Ice and have a peek at their recommendations to flush system using plain vinegar and water.

This issue must have reared its ugly head here on TC? Try a search and see what comes up if you have not already?

Mags

Ta Mags. I'm not sure if I can get away with epoxy and organic coolant or if I should buy a new waterpump/ clutch case. It seems to be a reoccurring problem with betas. One owner of a 200 in that article said the 200s have aluminium casings and not magnesium, I'm not so sure. A replacement would probably be better but more expensive. Thanks for the advice about flushing the system, will do before putting in new coolant. To repair or replace, that is the question...

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HI,

Sorry for the slow reply. I think you already have answers from Mags and others. Their answers are accurate but unfortunately they are not good news. At the risk of being redundant, here are my answers.

Yes, there looks to be significant corrosion inside the water pump portion of the housing. The surface inside the water pump area should look very much like the surface just to the right of the sight glass in the photo – more smooth looking like it has a nice coat of paint on it. In fact, it should have a nice coat of paint on it prevent the liquid coolant from touching bare metal. Once the paint loses a good seal on the metal, the coolant can start to “eat” the metal. Two problems exist: 1) The coolant “eats” the magnesium much faster than it “eats” aluminum. 2) Once the corrosion starts it can be very difficult to stop. Usually it is necessary to grind or cut away the corrosion until you get to good, solid metal below it with no signs of corrosion left. If you don’t get it all, the corrosion will continue, even if you put a good coat of paint on the entire metal surface.

It is difficult to be sure just from the picture but it looks like the corrosion has eaten away enough material to make holes completely through the metal allowing the coolant to pass through the little holes it created in the metal. We previously thought the coolant was leaking past the rubber seal on the water pump shaft. It seems now that the coolant is passing through the holes in the metal.

When things heat up, they expand. So, the coolant expands when hot and builds pressure while forces some of the coolant through the holes in the metal. When it cools, it gets smaller, creating a vacuum. This thermal expansion and contraction could explain how the water got into the gearbox when hot and possibly how the oil appeared to go down as the motor cooled because the oil got sucked into the cooling system.

Now to the question of what to do to fix it.

Choice A: Repair with sealant. Unless you can completely remove any existing corrosion and apply protection to prevent it from returning, any “fix” will be temporary. A poor fix could fail in weeks, a good fix could last years. A big part of poor versus good will be how well the existing corrosion is removed from the metal it is attacking, and how well you can seal that metal surface to keep the corrosion from “eating” the metal again. The other main part of the repair has to do with the heat expansion again. Because metal and plastic expand and contract at different rates with heat, the sealant can come unstuck from the metal allowing coolant to leak between them with the resultant leak and additional corrosion. Some of the epoxy type sealants have tiny particles of metal mixed in to try to make the epoxy expand and contract more like the base metal. One brand available in the states is called JB Weld. This is probably the cheapest fix in the short term.

Choice B: Repair by grinding out the corrosion, welding in new metal and machining it back to the original size and sealing it against corrosion. To do this well, the complete housing should be removed and the welding done by a professional. It might be cheaper than buying a new housing, it might not. Research can determine that. If done well this repair could last longer than the epoxy repair but if done poorly might not last as long.

Choice C: Replace the housing. If you do this, try to find a new housing made from aluminum (aluminium in the UK), rather than magnesium. See this link for a video of how to tell aluminum from magnesium. http://www.youtube.com/watch?v=g2A5o_MJ1-k . If you choose this option, be absolutely sure there is a good coating on the metal (even paint some extra layers on) because the slightest bit of bare metal that contacts the coolant will allow the coolant to start “eating” the base metal again. This choice is probably the most expensive but also has the best chance of lasting for a much longer time before failure.

Whichever choice you make, be sure to check that oil sight glass every day before riding so you can see very quickly if another leak is starting to pass coolant into the oil.

I am sorry that you are faced with this so early in your ownership of the bike. I wonder what recourse might be available to you with the previous seller. It is difficult to tell from the pics but if there had been a previous “temporary” repair, that previous owner had known, and did not tell you about, they might have some legal responsibility or even feel some moral responsibility to participate in the repair.

Good luck and keep up posted on how you get on.

Cheers. :beer:

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HI,

Sorry for the slow reply. I think you already have answers from Mags and others. Their answers are accurate but unfortunately they are not good news. At the risk of being redundant, here are my answers.

Yes, there looks to be significant corrosion inside the water pump portion of the housing. The surface inside the water pump area should look very much like the surface just to the right of the sight glass in the photo – more smooth looking like it has a nice coat of paint on it. In fact, it should have a nice coat of paint on it prevent the liquid coolant from touching bare metal. Once the paint loses a good seal on the metal, the coolant can start to “eat” the metal. Two problems exist: 1) The coolant “eats” the magnesium much faster than it “eats” aluminum. 2) Once the corrosion starts it can be very difficult to stop. Usually it is necessary to grind or cut away the corrosion until you get to good, solid metal below it with no signs of corrosion left. If you don’t get it all, the corrosion will continue, even if you put a good coat of paint on the entire metal surface.

It is difficult to be sure just from the picture but it looks like the corrosion has eaten away enough material to make holes completely through the metal allowing the coolant to pass through the little holes it created in the metal. We previously thought the coolant was leaking past the rubber seal on the water pump shaft. It seems now that the coolant is passing through the holes in the metal.

When things heat up, they expand. So, the coolant expands when hot and builds pressure while forces some of the coolant through the holes in the metal. When it cools, it gets smaller, creating a vacuum. This thermal expansion and contraction could explain how the water got into the gearbox when hot and possibly how the oil appeared to go down as the motor cooled because the oil got sucked into the cooling system.

Now to the question of what to do to fix it.

Choice A: Repair with sealant. Unless you can completely remove any existing corrosion and apply protection to prevent it from returning, any “fix” will be temporary. A poor fix could fail in weeks, a good fix could last years. A big part of poor versus good will be how well the existing corrosion is removed from the metal it is attacking, and how well you can seal that metal surface to keep the corrosion from “eating” the metal again. The other main part of the repair has to do with the heat expansion again. Because metal and plastic expand and contract at different rates with heat, the sealant can come unstuck from the metal allowing coolant to leak between them with the resultant leak and additional corrosion. Some of the epoxy type sealants have tiny particles of metal mixed in to try to make the epoxy expand and contract more like the base metal. One brand available in the states is called JB Weld. This is probably the cheapest fix in the short term.

Choice B: Repair by grinding out the corrosion, welding in new metal and machining it back to the original size and sealing it against corrosion. To do this well, the complete housing should be removed and the welding done by a professional. It might be cheaper than buying a new housing, it might not. Research can determine that. If done well this repair could last longer than the epoxy repair but if done poorly might not last as long.

Choice C: Replace the housing. If you do this, try to find a new housing made from aluminum (aluminium in the UK), rather than magnesium. See this link for a video of how to tell aluminum from magnesium. http://www.youtube.com/watch?v=g2A5o_MJ1-k . If you choose this option, be absolutely sure there is a good coating on the metal (even paint some extra layers on) because the slightest bit of bare metal that contacts the coolant will allow the coolant to start “eating” the base metal again. This choice is probably the most expensive but also has the best chance of lasting for a much longer time before failure.

Whichever choice you make, be sure to check that oil sight glass every day before riding so you can see very quickly if another leak is starting to pass coolant into the oil.

I am sorry that you are faced with this so early in your ownership of the bike. I wonder what recourse might be available to you with the previous seller. It is difficult to tell from the pics but if there had been a previous “temporary” repair, that previous owner had known, and did not tell you about, they might have some legal responsibility or even feel some moral responsibility to participate in the repair.

Good luck and keep up posted on how you get on.

Cheers. :beer:

Thanks for all the advice and help :)

I took it down to my friends workshop today and we worked on the bike. Got the clutch case off, thanks worldtrialchamp. The corrosion hadn't gone all the way through, but it didn't take much drilling out before we made a hole through to the case. Cleaned out all of the corrosion with a grinder then applied a sealant. Hopefully it will hold and work for now. I acknowledge the bike will need a new clutch casing once the sealant looses adhesion. It would not have taken long to eat right through the magnesium.

Where I believe water was getting in was the inner clutch case gasket. It had rotted and fell apart when we removed the casing. There were also signs that it had slipped in places and may have been that way for a long time.

I've got a new clutch case gasket on the way, we have replaced the water pump shaft and seal. Used sealant on the water pump housing and have put a new o ring on the clutch case cover. I've got the silkonene gear oil and organic coolant people on here have recommended.

We've also bled both brakes, bled the clutch. Taken the chain off for a clean, adjusted the throttle for free play and made a spacer for it. The two pieces that hold the air box are damaged (I'm guessing flipping the bike during a wheelie) so I have ordered two of these. Put on a new set of stickers to jazz him up, new number board and I will get some nice wide after market pegs when money allows. New stand and bracket as the old one had snapped off. Adjusted the suspension, handle bar controls to suit.

At least the engine turns over well, no starting issues baring poor technique in the beginning. I bend the other leg too now ;)

I have contacted the previous owner to ask if he was aware of these issues, he hasn't got back in touch- surprise surprise. Was 1300 a lot to pay for a bike of this age and condition? I feel like I've been a bit of a fool. A few friends have told me to sell the bike, I'd rather do her up to a high standard, I wouldn't sell a bike with problems to someone and riding a trials bike is too much fun :D

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I applaud your willingness to jump in and work on the bike (with the help of a friend). It sounds like you are doing a good job of fixing up many things that have needed a better repair then they had in the past. It is a good feeling to know that things have been put right and they will be unlikely to fail for a long time into the future.

I don't know the market value of bikes in your area but it doesn't sound like you made a bad deal. I do think you have given us all a good reminder to think and do some research before we buy a used piece of equipment. We are quite fortunate to have a resource like Trials Central to read old posts of what to be aware of when looking at a used bike.

I look forward to hearing how you do in upcoming trials.

Keep your feet up and keep smiling!

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I applaud your willingness to jump in and work on the bike (with the help of a friend). It sounds like you are doing a good job of fixing up many things that have needed a better repair then they had in the past. It is a good feeling to know that things have been put right and they will be unlikely to fail for a long time into the future.

I don't know the market value of bikes in your area but it doesn't sound like you made a bad deal. I do think you have given us all a good reminder to think and do some research before we buy a used piece of equipment. We are quite fortunate to have a resource like Trials Central to read old posts of what to be aware of when looking at a used bike.

I look forward to hearing how you do in upcoming trials.

Keep your feet up and keep smiling!

Thanks TAF. I feel very fortunate that trials central is here, there is so much information about the bike I would have been lost without.

The gasket arrived, put her back together today and put in some motul factory line coolant, hopefully it'll do the trick. A new seal and cir-clip for the waterpump went on and a new magnetic drain plug for the gearbox. I've filled her up with light gear oil and put in 500ml as recommended by some here. Why does the glass look empty after I've filled her up, does 50ml make that much of a difference?

post-20468-0-90133700-1412624084_thumb.jpg

I also found one of the brackets for the gearbox was cracked, replaced both of those- rather elaborate attachments to the rear shock and the exhaust- tricky to put back together!

post-20468-0-06545400-1412624071_thumb.jpg

The spark plug has blackened within two rides (definitely the correct plug) Anyone have an explanation?

Thanks everyone for the help so far.

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