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87 CR125 Resto: Q:Trouble w/ corrosion and some random questions
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Posted by: hellbertos---------------------

Hi guys- checking back in. The tear down is finally underway and I have run into a few snags. I wasn't prepared for how tough it would be to deal w/ a bike that has been sitting for so long. Quite a few frozen nuts n' bolts!! Managed to get past many, but I'm stuck at the impeller.

There was a ton of precipitated matter in the water pump chamber as well as corrosion. I've tried everything I can think of but can't get it to budge. I am leery of stripping it out since there is so much corrosion. Any of you guys ever come across this?? Any suggestions of methods to use to free the thing up. I really want to get it going and get the cases split.

Also, there is some depositing (chalky white) in the water jacket on the head (a lot where the fluid comes in) and in the cylinder(not much but noticeable). Does anyone know of a process to clean these out; either at home in the garage or a local shop(boil out or treatment or something??) . They seem in good shape but obviously need to be sanitized before I can reuse them.

The hoses seem to be in good shape for the most part, but, like every thing else, I want them to be 99.9%. Leaning on just buying new ones. Anyone have any input there based on past experience?? I'd like to reuse as much as I can to keep the cost down, but don't want to jeopardize finished product's reliability.

Lastly, and I think I asked this before, any ideas on radiators. They look ok when I peek inside, but after seeing all the deposits, I feel like they need to be flush. Someone previously recommended a local rad shop but I am leery of those guys w/ my small moto rads. Anyone care to weigh in?

TIA for any info and/or suggestions!

Posted by: zoommx---------------------

You should be able to remove the clutch cover without disassembling the water pump, at least my '86 will. After I had it off, I held the gear with a leather glove or wrapped in a towel and use an impact driver on the impeller. LOTS of corrosion in impeller area?? I suspect a magnesium case and etheylene glyocol/water mix coolant. Quite common on mid-80s CRs. I believe KTM dealt with the magnesium/coolant corrosion, as well as Cannondale, and even more recently some suzuki quads.

good luck

Posted by: sm7482---------------------

Told you to whatch out for that, now i dunno about the 87 year but the 84 year the impeller was part of the nut. meaning the whole impeller tightens down on the shaft. the impeller for our bike had a nut welded to it, we didnt know this until a while afterwards when we were so frustrated trying to hold the impeller and turn the nut. If this is the case with you then you have to spin the whole impeller off, not just the welded nut on the impeller, that is if 87 doesnt use the modern plastic impellers. i dount remember if it was left losen or right losen. if the impeller spins clockwise try turning the impeller to the right, if it loosens then its lefty tighty righty loosey. as for corosion try any corosion cleaner, watch out for a few things though such as chemicals that will eat the aluminum. a buddy of mine put sume corosion cleaner on the right hand case and the case started smoking. also watch out for any pin holes that may cause leaking after the corrosion is cleaned out. if theres any spots were its coroded through or really worn down leaving small pin holes it is possible the corosion has kept them sealed off but once cleaned it may leave open holes. as for the white powdery stuff, once the engines back together try purchasing some of that radiater cleaner. what you do is pour it in the radiators and run your bike for a few minuts while the flush circulates through the engine clearing out all the junk you couldn't reach. once the time is up drain it out and refill with the antifreez. make sure you buy the stuff mad for motorcycles. Really watch out for pin holes, now that we know theres corosion you cant help but stress that. Good luck! get some pictures going, id like to see your progress!

Posted by: Uchytil---------------------

Be careful. I've restored a few early 80's and the galvanic action between magnesium, aluminum, and steel is probelmatic using the lesser metal as a sacrificial point (like a zinc in marine apps). The big problem is the use of tap water which contained minerals. Here's what I do: Use penetrants and heat to remove frozen bolts. Work very slowly, ie. soak parts overnight, or so, dry, and then apply heat to the outer bores. You can also try a quick quench with cold water to try and break the bond. Whatever you do work slow. The corroded parts can be cleaned by wire wheel, bead blast, etc. I use an engine type epoxy to fill in, and smooth, corroded areas in the cooling system. Use sparingly. If the damage is extensive look for newer parts. The radiators are hard to clean being thin aluminum and subject to destruction with some acid cleaners. I used mild acids like cokeacola, or vinegar with little luck. You can send them out to a shop that specilizes in these. I ended up finding a few used ones that were pretty good which was the best bet. The white powder can be cleaned up with mild acid like I mentioned but don't overdo anything. Rinse well with mild detergent. Only use distilled water and antifreeze mix. Replace the hoses if you can afford to. Good luck! Oh yeah, don't use stainless steel fasteners on the engine either. Good luck!

Posted by: whenfoxforks-ruled---------------------

Call around to the radiator repair shops. Tell them you need a set of small aluminum motorcycle radiators cleaned and inspected. Few years ago 35 dollars got twisted leaky radiators good as new. The cap also.

Posted by: zoommx---------------------

Non-water propelyne glycol won't corrode the magnesium either- i.e. Evans NPG+ or NPG+R is what I use. pricey though at about 35 bucks/gallon.

Posted by: hellbertos---------------------

Thanks for all the feedback guys! Hey sm, yeah, I remember that and when I popped off the rad hose, your post was the first thing that popped into my mind.

Lets see, it does appear that it threads on to the shaft via welded bolt. I wish I'd have popped it before pulling the motor from the bike, but I'll try the suggestion posted to hold it. I read both Clymer and Honda service manuals and no mention of reverse threading, but I will recheck the direction of rotation.

Given all the corrosion I'm inclined to think that I'll need to employ a few of the suggestions here. Any tips on brands of chem corrosion cleaners to try?

I may try heating it up w/ the propane torch (carefully) and w/o any chems on it, obviously. It looks like those parts are still available based on online microfiche, so I'll likely replace.

Also, any tips on the head (significant deposits) and cylinder(not too much)?? Corrosion cleaner and a small brush?? THe head in particular looks pretty bad.

Anyhow, thanx for the tips. I'll start taking some pix and post 'em up shortly.

Posted by: whenfoxforks-ruled---------------------

I thought most all the corrosion stemmed from putting tap water in them? If so, wouldn't CLR work? Granted, parts can be corroded to the point beyond repair. And anytime different metals touch each other, there WILL be corrosion, sooner or later. Blue loctite on threads does more than help secure the bolt. It does reduce corrosion, steel bolts into aluminum cases, drawing the magnesium cover. Bet you a fiber washer could have helped reduce the corrosion.

Posted by: hellbertos---------------------

CLR huh?? I'll look it up and give a try. I'd always used mix of distilled h20/Eth. Gly. but I honestly can't remember clearly. I probably lapsed right when I shouldn't have before it went to storage. At this point I am prepared to have to purchase some new parts, but it would be nice if some of this stuff ends up being usable.

Thx for the tip. I'll check out CLR.

Posted by: Ol'89r---------------------

Quote:

Originally Posted by hellbertos

Given all the corrosion I'm inclined to think that I'll need to employ a few of the suggestions here. Any tips on brands of chem corrosion cleaners to try?

Also, any tips on the head (significant deposits) and cylinder(not too much)?? Corrosion cleaner and a small brush?? THe head in particular looks pretty bad.
.

Find someone in your area that does Soda Blasting. That will remove all of the deposits and not damage the parts. It will also work for your hoses. Using CLR or any other chem cleaner can eat the magnesium even more. Like others have pointed out, the mid 80's CR cases had very bad corrosion problems. Like sm7482 said, check the cases closely for pin holes when your done.

A radiator shop will be able to clean out your radiators or try doing a search on Mylars radiator repair. These guys used to be able to repair just about any radiator for 35 bucks.

Posted by: hellbertos---------------------

Thanks 89'r! I will look into soda blasting. I was leery of CLR after I looked into it, but still may try a drop or two on the impeller shaft to free up that dang inpeller.

I did look at Mylers (http://www.motorcycleradiators.com/) but I think my rads just need cleaning/flushing, so I will poke around locally and see what I can turn up.

Thanks for your input!

Posted by: hellbertos---------------------

Quick follow-up: Talked a shop that does marine restoration who offer soda blasting. The guy I spoke w/ said he does hot rod and moto resto's at home and offered up that the corrosion has likely damaged the part/thinned the metal to a point as to make it not worth reinstalling.

Granted he didn't see the items in question, but, just curious here... in case... in such a situation, would there be anyway to cost-effectively rehab a component? Like a machine shop that could weld it up and grind it out?? Just wondering in case it comes to that. Looks like the heads are not available new.

Posted by: sm7482---------------------

get sum pics so we could judge better. as for the cases and such or even the head welding maybe an option if the areas welded are easily accesed. I know for our right side case we were able to weld up the wholes and grind it down, it's worked well. DONT USE jb weld. weve tried it and it works well for a while but then it softens and turns into a paste then leaks. have you tried running the part numbers to see if there are other models that use the same head? try ebay. but more than likely, with the right tools it's probally fixable. for the impell. er you could try holding the mag/flywheel with flywheel holders and then spin the whole impeller loose. for the cylinder/ cyilinder head/ and crank case cavitys try useing baby bottle cleaning brushes, the flexible one might be better and ream out the pathways kind of like a hone. For the circular coolant ways you may even be able to attach it to a drill and "hone" out the coolant pathways real well. try finding them in diffrent sizes for diffrent size pathways and areas. You can even buy welding brushes, the small wire ones that look like baby bottle brushes. try to get a stiff one eather way. Realy watch for them pinholes. As for the guy who said some areas may be to thin to fix we can't tell untill its cleaned and expected. Even if theres some good size pin holes they can be drilled and filled just like a cavity. Id like to see some pictures of the challenges your faceing, impeller corosion, cylinder head, cylinder and some others.

Posted by: hellbertos---------------------

Great input sm! Dang, you guys are good. As a rookie I am still just learning the trix of the trade. LOVED the bottle brushes on a drill. I used to have some cool attachments for the dang Dremel, but that got lent out (I know, I know... I finally learned). I will definitely look at that to clean the cylinder's water jacket. Its the head I am more worried about. I'll have to see whats doing w/ the right side case.

Also, great idea about spinning the impeller off from the other side! I need a better tool to hold the mag. That will be looked at first thing tomorrow.

Went to take a few pix tonight but my old camera chewed through the batteries I put in it last week. I'll get that sorted out as well and get some pix going. I really appreciate the guidance!

Any tips on suppliers for mutli-sized bottle brushes?? Esp. for ones that would fit in the drill?? That would be nice.

Posted by: Ol'89r---------------------

Quote:

Originally Posted by hellbertos

Quick follow-up: Talked a shop that does marine restoration who offer soda blasting. The guy I spoke w/ said he does hot rod and moto resto's at home and offered up that the corrosion has likely damaged the part/thinned the metal to a point as to make it not worth reinstalling.

Granted he didn't see the items in question, but, just curious here... in case... in such a situation, would there be anyway to cost-effectively rehab a component? Like a machine shop that could weld it up and grind it out?? Just wondering in case it comes to that. Looks like the heads are not available new.

He is correct about the 'thinning of the case. Those cases have a very high content of magnesium in them. Most of the time they can be tig welded and remachined. But, if they are eaten to a point where they are thin, it is very hard to weld them without blowing through the case. Also, it's hard to find someone that can tig weld magnesium.

Soda Blasting will clean the case without removing metal like Bead Blasting or Sand Blasting will do. Also, soda is inert so, if a little is left in the case it won't hurt anything as opposed to sand or glass bead. After the case is blasted, check it closely for holes. lay the case on its outside and fill it with gasoline. Let it sit overnight. If the gas doesn't leak through, you should be good to go.

The CLR will work on your radiators and hoses. Most of the crust in the hoses will come out if you take your hand and crush the hoses and then blow them out with compressed air. If you use the CLR in your radiators, be sure to rinse the radiators with DISTILLED water after you are done to neutralize the CLR.

On the impeller, try using a little heat before removing it. Use a torch DIRECTLY on the impeller. This will expand the impeller and loosen its grip on the shaft. Be careful not to get the flame on the magnesium side case or your motorcycle will turn into a giant sparkler.

If for any reason the magnesium case does catch fire, DON'T THROW WATER ON IT! That will cause it to explode. Just take it outside and order some hot dogs.

For chemicals to treat or prevent rust and corrosion, check out this site---> www.eastwood.com

Posted by: sm7482---------------------

Quote:

Originally Posted by Ol'89r

If for any reason the magnesium case does catch fire, DON'T THROW WATER ON IT! That will cause it to explode. Just take it outside and order some hot dogs.

For chemicals to treat or prevent rust and corrosion, check out this site---> www.eastwood.com

Actually for our right crank cover we used a propain torch and some low heat aluminum welding rod. we heated up the areas we needed to weld then added the rod, kinda like soldering. it's worked well and our case didn't explode/catch fire ect.

as for the cleaning brushes you should be able to find them at any hardware stores. they call them plumers brushes/tubing brush ect. For drill attatchment you should be able to find a cleaning brush with a rather thick wire stem, try checking around for flexible ones, http://www.harborfreight.com/cpi/ct...temnumber=90631.
capture some good pictures of the head seeing how thats your main concern, then we'll go from there. Try holding the flywheel then spinning the impeller or viseversa but get a flywheel holder, you woldnt want to damage the flywheel.

Posted by: sm7482---------------------

Oh but before you try anything dealing with heating up the parts being removed really try to break it free with elbow grease, if for some reason the magnesium does ignight there really isn't a way to put it out.

Posted by: MOgle80---------------------

http://www.mrcycles.com/fiche_image_popup.asp?fveh=3227&section=137073&year=1987&make=Honda&category=Motorcycles&dc=792&name=WATER+PUMP[/IMG] THIS Should show the impeller as a threaded on piece

Posted by: Ol'89r---------------------

Quote:

Originally Posted by sm7482

If the case is magnesium, DO NOT USE OPEN FLAME ON IT. This is a very bad idea. Look on the side of the case. If it is mag, it will say magnesium on the case. Using open flame on a mag case can catch it on fire. Mag can be tig welded because tig welding uses an inert gas to eliminate oxygen from the welding area. Without the oxygen, the case will not catch on fire. Using open flame in an oxygenated environment is VERY dangerous with magnesium. Once it catches fire, you can't put it out.

The impeller is made of aluminum. It's ok to use a little heat on it to expand and loosen it instead of just using force and hoping for the best. Just using elbow grease is a good way to break something.

The nut is not welded on the impeller, it is cast as one piece.

Posted by: sm7482---------------------

Quote:

Originally Posted by Ol'89r

very true indeed, our right case very well may have been made of aluminum, but even if mag is flammable the heat thats generated by heating the impeller just may ignite it no? was it cheaper to make an aluminum mag alloy than all aluminum? seams dangerous no? I would still try using wd40 or or similar to free the impeller than heat, who knows what could happen but if it comes to it you gatta do what you gotta do. try a little heat, hold the flywheel with flywheel holders and try to unscrew the impeller as a whole.

Posted by: whenfoxforks-ruled---------------------

You are fortunate to have one of two years that the ama made the pros race what came off the assembly line. At the time, they were factory bikes.

Posted by: Ol'89r---------------------

Quote:

Originally Posted by sm7482

No, as long as you use a torch and apply the heat directly to the impeller it won't ignite the mag.

One of the problems with using a penetrating oil is, it is very difficult to get the penetrating oil up behind the impeller. Also, WD40 is a solvent, not a penetrating solution.

The reason they made the cases from magnesium was to save weight.

Posted by: hellbertos---------------------

Hey guys- Thanks a ton for all the input! Some family issues kept me away from the computer, so I lagged on posting, but here's the update...

So, I went w/ setting the cases on their side and pooling a little penetrating oil on the end of the impeller. I let it soak in all day, dripped a bit more on later and let it sit over night. My buddy has been popping in and helping me out w/ it and he encouraged me to hit it in the morning w/ his extra hands and smarts (he is an airline mech.).

We talked it over and agreed we'd save heating it as a last resort. The main trouble was holding the crank so we could torque on it; to see if the penetrating oil would even work. Next time that comes off while the engine is still in the bike!! Given the problem, my pal came up w/ a great idea. We pulled the clutch basket and held the shaft from the other side by pinching off what I believe is the ATAC drive gear. What I found interesting is that it seemed to come off relatively easily which was good since the gear in question is plastic. We both felt the penetrating oil did its job well.

With the impeller out of the way, we proceeded ahead and got the cases split. I am excited to get to this point and much appreciate all the input so far.

At the risk of wearing out all the goodwill... I still have the corrosion issues which I am unsure about, as well as general rebuild questions (like how to remove the main bearings from the crank?? I guess I better start looking for a good machinist...) and I'm sure many future questions as the project goes on. Given this, I am not sure the etiquette for posting. Should I keep reopening this post or repost as new questions/problems arise?

By the way, I have pictures of the corrosion that I will post once I return home next week. Thanks again for all the info so far!!

Posted by: hellbertos---------------------

You know, I forgot to mention that in addition to holding the impeller by pinching off the gear behind, my buddy also devised a way to hold the impeller since the nut/casting on the impeller was stripping out; I believe due to the corrosion.

What he did was wedged a crescent wrench in between the impeller blades so we could actually grip the impeller. We then used vicegrips on the crescent wrench to turn it. As stated in the previous post, w/ the impeller shaft held from behind, it actually popped off relatively easily. The technique did mar the impeller, but it is off and needs to be replaced anyway, so no big deal.

I thought it was a pretty inventive way of getting around the problem... now if I can just keep coming up w/ those. Heh...

Posted by: SMMWest---------------------

Just did a Restoration of a 1985 Honda CR125, but then the guy that had it before me painted the frame White and I repainted it White and after talking with the guys at BBR and also Ron Lechien, I want it to be as close to Original as possible so I am going to tear down the entire thing again and repaint the frame Honda Orange (trying to find some old cans of PJ-1) or Chevy Engine Orange.

Good luck with your project.

Posted by: hellbertos---------------------

Quote:

Originally Posted by whenfoxforks-ruled

You are fortunate to have one of two years that the ama made the pros race what came off the assembly line. At the time, they were factory bikes.

Thanx! Yeah, I really loved the bike. Even when it was a couple years old, it still felt as though it held its own. One of the reasons I thought it would be a good rebuild as well...

Thanx SMMWest! Let me know if you find any extra PJ-1 paint in Honda orange. I looked around a bit but didn't find any. I'll look at the Chev engine paint when I get to that point, but, in all likelihood, if I do paint it I'll probably go to an auto paint shop and see if they'll color match.

BTW, I had an 85 CR125 way back when also. Sold it to get my 87. Loved that bike too. Nice work keeping it alive... and, in my opinion, nice work returning the frame to stock. I remember guys doing their frames white back then and never really liked it. I recall it being the "Euro" look. The custom aspect was cool but I guess I just thought the white clashed too much w/ the rest of the bike + got dirty and ugly fast... my fashion rant for the year...

Posted by: Ol'89r---------------------

Quote:

Originally Posted by hellbertos

At the risk of wearing out all the goodwill... I still have the corrosion issues which I am unsure about, as well as general rebuild questions (like how to remove the main bearings from the crank?? I guess I better start looking for a good machinist...) and I'm sure many future questions as the project goes on. Given this, I am not sure the etiquette for posting. Should I keep reopening this post or repost as new questions/problems arise?

No worries. You can keep this thread going for your project and we will check back in. If your friend is an AP mechanic he should be sharp enough to help you through most of your rebuild problems. Use heat to remove the crank from the cases. Your main cases are aluminum, not magnesium, so you can use direct flame on them without any danger of catching them on fire. You have to be careful not to overheat them because they will melt at a little over 1100 degrees. Heat them until you can sizzle a drop of water on the case. Then, your bearings will almost fall out. Reinstall them using the same method.

You will need a bearing splitter to remove the bearing from the crank. It is a wedge type of device that goes under the bearing and pushes it up off of the crank. Check with your local dealer to order one. You can also heat the bearing and try to pry it up by using two levers on opposite sides of the bearing. If that doesn't work, you will need the bearing splitter. Your local shop may remove the bearings for you for a small charge.

Posted by: SMMWest---------------------

Quote:

Originally Posted by hellbertos

Thanx SMMWest! Let me know if you find any extra PJ-1 paint in Honda orange. I looked around a bit but didn't find any. I'll look at the Chev engine paint when I get to that point, but, in all likelihood, if I do paint it I'll probably go to an auto paint shop and see if they'll color match.

BTW, I had an 85 CR125 way back when also. Sold it to get my 87. Loved that bike too. Nice work keeping it alive... and, in my opinion, nice work returning the frame to stock. I remember guys doing their frames white back then and never really liked it. I recall it being the "Euro" look. The custom aspect was cool but I guess I just thought the white clashed too much w/ the rest of the bike + got dirty and ugly fast... my fashion rant for the year...

Haven't been able to track down any PJ-1 Honda Orange Paint, but I can find tons of 1988-1989 Honda Red.

I think I will put this whole thing back together with the "Euro" look White Frame (after tearing it all the way back down again) and get in some riding and racing on this thing and then right before Hangtown Amateur Day this year I will tear it all back down and get a Automobile Paint Shop to do my frame also depending on the price. If the price is too high then I will go with the Chevy Engine Block Orange paint and do it myself.

I think besides my old 1982 Suzuki RM125 that my 1988 Honda CR125 was my all time favorite bike and me getting this 1985 Honda CR125 is bringing back that feeling. It just doesn't sit the same as my old 1988 Honda CR125 in the Front. I am going to throw on some Answer Alumilite Honda CR HI Bend Bars and see if that helps.

Posted by: 2strokerfun---------------------

Quote:

Originally Posted by Ol'89r

If your friend is an AP mechanic he should be sharp enough to help you through most of your rebuild problems.

His friend may very well be able and competent to help him. But I went through A&P school in late '70s and I have to say I wouldn't let about half the guys in my class change the water in my dog's bowl. A lot of people with A&P licenses are excellent mechanics, but certainly not all. Some people liked and understood working on engines and some just wanted a way to make a living working for a major airline. But almost every general aviation mechanic I've ever known is an excellent all around mechanic, too.

Posted by: SMMWest---------------------

How are things going with this project?

Posted by: mas2de---------------------

(kind of late but...)
Magnesium doesn't much like to ignite when it is in large chunks. filings and thin strips will blind you and won't blow out but as for open flame on big pieces of magnesium, you should be ok if you're careful. And welding magnesium is extremely difficult. I believe it is still a challenge for professional welders, but should be do-able. But it is not much for the amateur. The TIG easily burns through the magnesium and has other problems too.
And doesn't soda blasting leave a funky residue and work it's way into more crevices than sand? Guess it wouldn't much matter for around the impellar and if you're rebuilding the rest of the stuff.
You can get the bearings off the crank ok, it is putting them back on which is the problem. For that you need something a little more precision. A good machine shop really ought to be able to put it back together right.
Glad to hear it's going alright. and good luck.
see ya,
Mike

Posted by: SMMWest---------------------

Had to sell the 1985 Honda CR125 yesterday that I had rebuilt from the ground up. Couldn't miss a Child Support Payment, so it had to go. Someday when I can get ahead I think I will purchase another one and rebuild it the same or grab a 1986 Yamaha YZ490 again. Sad Sad Day.

Posted by: 2strokerfun---------------------

Quote:

Originally Posted by SMMWest

Couldn't miss a Child Support Payment, so it had to go.

You're a better man for it.
Hope you get another one someday to rebuild.

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87 CR125 Resto: Q:Trouble w/ corrosion and some random questions

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