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Discussion Starter #1
It's been a few months since I introduced myself and the poor neglected SL350 I dragged home. Thanks again for the warm welcome and words of encouragement from my introductory post. Now it's time to get to work! I bought this as a long term project. Over the years I've had plenty of 2-wheeled winter projects that needed various levels of TLC (and $$$) to get back on the road by Springtime. I had no such delusions when I spotted this one. I wanted something that will keep me busy during idle times for a while - I don't care if it takes 2 or 3 years before it's "finished" (are they ever?)
For those of you that missed my intro, here's what I've gotten myself into
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The owner was very upfront about the bike's condition. It had been sitting outside under a tarp and had been used as a parts bike for the very nice SL he had in his garage. The engine was stuck, but he threw in a CL350 engine that I'm using for parts. Part of the deal included a set of cut off CL350 exhaust pipes since the stock pipes were long gone. It didn't take long to start the deconstruction process, and to start making a list of parts I'll be needing to replace rusty, broken or missing bits.
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A full blown restoration is out of the question here. The bike needs way too much to make it worthwhile - there's just no return on investment here! I'm thinking more of a minimalist resto-mod scrambler running a batteryless ignition and minimal electrics (no gauges) that'll be simple to wire up. Of course, plans may change - that's why I'm playing it loose for now. And a lot depends on the kind of deals I stumble upon as I'm scrounging parts!
 

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Discussion Starter #2 (Edited)
Since the engine will be one of the more expensive propositions I decided to tackle it first. I appreciate that the owner threw in a CL350 motor as a source for free parts, it will probably come in handy. If nothing else, I can sell those parts on eBay to help fund parts I'll be buying! Here's both of them on the bench
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I began teardown of the SL motor first. The head came off pretty easily and everything appeared to be in fairly good condition, including the cam and followers. I try to work slowly and use a lot of Kroil to help loosen fasteners up. I also try to take lots of pictures along the way, not only to aid reassembly, but to tell my story here. Once I got a look inside the cylinders it was obvious that the right one was very rusty and locked up. Turned out to be a good place to stop, so I let everything marinate in kerosene and PBlaster for a couple of days.
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After a few days it was obvious that any combination of penetrating lubricant, leverage and swearing wasn't going to budge the stuck piston. Hammer Time! It only took a couple of whacks to start to move the piston down the bore. I knew the pistons and cylinders would not be reusable, but tried to be careful not to hurt anything else (or me) while using some persuasion here. Finally, I was able to lift the cylinders off. The left piston looked okay and the rings were free, but I still removed it and placed it in the "Do not reuse" bin along with it's mate and the cylinders.
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So, how am I doing guys? Enough pictures? :grin:
 

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You're doing very well. The pistons appear to be toast but the cylinders may yet be useable with a bore job.
 

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Discussion Starter #6
Wow... that might be the worst piston condition I've ever seen
Yikes! I'd have to agree! Fortunately, the spare motor has a good set of cylinders I'll be using, so I can donate these to someone who's looking for a set to bore.
 

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Looking good so far Pops!

EDIT
BTW - I noticed you mentioned a batteryless ignition. Everyone has always told me these things can't be set up for batteryless operation due to low end low voltage.
I would love to be able to set my current project up that way. I can solder wires with the best of em, but true electrical theory often leaves me dumbfounded. Sooo, what's the word? Is it possible? Maybe with a different stator? In my own case, I will have NO lights, gauges, etc. Other than a simple kill switch the only thing electric on this bike will be the ignition system. Sorry for the hijack Pops! :cool:
 

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Wow... that might be the worst piston condition I've ever seen
Yeah, that's the cumulative effect of every old-timer method of removing a seized piston not working. I soaked that thing in all types of stuff for days on end, hit it with things, drilled holes in the top, set it on fire...what finally got it out was a hole saw :D
 

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Discussion Starter #10
Ouch! You guys are giving me the willies talking about all the drastic measures you had to take! I guess I was fortunate only needing a 4 pound sledge and a piece of 2x2! Anyway, once I had the top end apart it was not long before I had the cases split and was able to disassemble and inspect all the internals.
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I expected the worst when I saw all the moisture and coagulated oily goo, but everything looked and felt good after a good scrubbing in the parts washer. I was very pleased to discover the bearings spun smoothly and quietly and there was no play in the rod bearings. I lubed everything well, wrapped them up and set them aside for the time being. The cases looked like they had been at the bottom of the local swamp for a few years, so they got the next scrubbing. After getting the initial layer of mung off, I hit them with the soda blaster then gave them another good wash.
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It was about that time I realized I'd lost the little rubber ball that blocks an oil passage in the case bottom. (You guys know exactly what little ball I'm talking about!) After agonizing about it a couple of days, I donned some heavy rubber gloves and fished around the bottom of the big stainless sink full of solvent we're using as a makeshift parts washer. I must be living right, because I managed to find it in a big wad of goo I pulled out of the bottom recesses!
 
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Hahaha That little rubber ball...I've had some little rubber ball induced anxieties as well. Glad you found it. What do you think of the soda blasting? I have access to a bead blast cabinet and I used it on all my engine components. I swear I'll never do that again. Those damned beads get EVERYWHERE and they're just the worst to get rid of. After running everything through the dishwasher twice, I still had to blow glass beads out of every threaded orifice and every hidden crevice everywhere. I'm now staunchly anti-bead.
 

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Discussion Starter #12
The biggest advantage of soda is it dissolves when you wash your part afterward. You do need to wash the parts well when you're finished if you intend to paint the part - any left over soda residue will lift the paint when you're done. Just google "painting after soda blasting." I like the finish the blasting leaves - it's clean but not perfect. That's the kind of build I'm going after here.
I've never tried bead blasting before. A hot rod builder buddy has a cabinet, I've been meaning to give it a try.
 

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Yeah, soda seems like a way tidier option. The glass beads are awesome for what they do...they indiscriminately strip things bare. I think there you can achieve different finishes with different size beads, my engine looks matte gray after blasting all the parts. I think it's really cool, but it's definitely a long ways from the stock appearance. At any rate, there are tons of things I would absolutely bead blast again...engine components aren't going to be one of them. It's just too much hassle to clean up. DSC_0025.jpg
 

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Discussion Starter #14
Since the whole top end is trashed on this engine, I figured I'd tear into the spare to see how many of the components are good enough to switch over. Since I'd already torn down the one engine, and this one was on the bench with nothing in the way, this one came apart very quickly.
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I didn't notice it immediately, but once I had the top end completely apart it appears that something has come apart and bounced around up here sometime in the past. The tops of the pistons have plenty of scarring around their periphery, and the combustion chambers in the head have excess material "welded" around the edges. In addition, the head has one TimeSert that came out with the plug when I pulled it. So much for using this cylinder head...
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I cleaned up the pistons enough to see "0.25" stamped on the crowns, so this one's already been bored once. Given the damage to the other parts, I was really surprised to see the cylinders were in great shape, just mud-caked and generally filthy. A little clean-up session in the laundry room sink worked wonders.
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A little careful eBay scrounging has yielded a nice new pair of properly sized pistons and new oversize rings too - and very reasonably priced I might add! It certainly helps to find good deals on parts. I need to keep this project under the household budget radar, if you know what I mean... That being said, I'm in the process of cleaning up the rest of the spare engine parts I won't be needing. If anybody needs 350 twin engine parts, give me a shout. I'll let you have them for the cost of shipping. In the interest of keeping this thread cleaner, I'll probably start another thread in the classifieds with descriptions and pictures.
 
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Enjoyed the read and pictures so far. Looking forward to watching progress too. Im going to have to lookup whats happening with that easy off ;) Enjoying these processes and learning. Thanks for sharing!
 

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Watching this one, with interest, as it is ironically the same model SL350, that I have and I also am not going to even think about a "Restoration" either, because of the parts prices & no assurance of the return, should I need or decide to sell it later on. I never thought of the term Resto Mod Scrambler, but basically, I guess that is basically my goal as well. Only I have decent gauges and am going to use them. Also I am keeping the electrics, but no lights at this point (though I might add them later on. Anyway, I am liking your project and attitude regarding it. ;) One thing mine does have, is a solid exhaust system, though it is a 2 into 1 low pipe, that is kinda bulky, to me and way too quiet! So, I am hoping to be fortunate enough, to come across pipes of some kind (CL, CB or even SL) that might need some work, to make them presentable enough and some kind of mufflers, that I can rework, to give it some decent sound, but not like straight pipes would be.

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Time to start putting stuff back together. After I got the cases all cleaned and blasted I masked off everything I didn't want to paint and shot a couple coats of High Heat Primer to give me a good base for the finish coat. Probably unnecessary, but I'm into experimenting with this bike, and wanted to see what kind of results I'd get. Oh, while I was cleaning, I ground the rivets off the windage tray in the bottom case and pulled it off so I could get all the goo out of there - glad I did! I drilled and tapped the bosses and re-attached the tray with pan head screws.
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Then it was on to the finish coat. I used DupliColor Ceramic Engine Paint for the cases. I've had good luck with it with my other projects, and thought it would do the job here too. I'll have to double check, but I think I went with the Cast Coat Aluminum. Anyway, very pleased with the way it lays down and the finish you get.
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After I let it cure for a few days I got back to reassembling the bottom end. The local Honda dealer is only a couple miles away (this could be dangerous!) so I hit them up for a fresh tube of HondaBond hi temp case sealer. I had given the gearsets a good cleaning and inspection, and lubed the bearings well before putting everything in place.
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The hardware was looking pretty cruddy, so a little time on the wire wheel made them look better. If this were a proper restoration, I would have purchased new hardware or investigated the home plating process some of you have used. Maybe next project... I always enjoy breaking out the torque wrench - there's just something satisfying about feeling that gentle "click" when you hit your set torque! So, the bottom end is together and ready for those fresh pistons and rings!
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Discussion Starter #19
Spring has definitely sprung here in the beautiful Shenandoah Valley, and even though the lawn and household maintenance have claimed most of my free time I still get a little "garage therapy" in whenever I can. One rainy weekend I was able to start work on the top end. After checking the ring gaps on my new rings and verifying everything's well within spec, I assembled them to my new pistons.
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Next step was to gather up the new circlips and assemble the pistons to the rods. I had a devil of a time getting the first circlips into their grooves just holding the pistons in my hands. Once I had the pistons installed with the wristpins in place, the remaining 2 circlips snapped into their grooves easy-peasy. It dawned on me that they installed so effortlessly because the wristpins were backing them up, keeping them from going past the groove. Duh! Garage tip - when installing the first circlip, just slide the wristpin into the piston to keep the circlip from "overshooting" the groove. I suppose I could have installed all four with the pistons already in place on the rods, but I like to lessen my chances of any small parts falling into the crankcase. Been there...done that!
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A couple weeks prior I had cleaned and painted the cylinders, so now they were nice and dry. I double checked to make sure everything was ready to go together - cam guide and tensioner assembly in place, tensioner retainer rubbers in place, fresh cylinder base o-rings and gasket. I carefully slid the cylinders down over the tops of the pistons and was able to press the rings together with my fingers so they gently slid up into the cylinders. The oil ring on the second cylinder was the only one that gave me any trouble, and I used a popsicle stick to help compress it.
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That's when I noticed something wasn't quite right...the jugs weren't seating tightly against the case. I'd remembered reading a couple of threads about the o-rings being too fat in certain aftermarket gasket kits, so I figured that was the case here. A quick trip to the Honda dealer, and Lisa the friendly parts girl assured me they are still available from Honda. So, a quick $18 later, I have the right o-rings on order and will swap them out when they come in. One step forward, two steps back. Oh well, it's a good thing this is a long term project.
 
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Got a call from the dealer that my parts were in. I walked in only to discover an old chum is the lead sales guy there. (Uh-oh, this could really be dangerous!) We spent a few minutes catching up on what we and our kids are doing, then we took a quick lap around the sales floor. Sorry, the new models just don't excite me, maybe this won't be so dangerous after all.

Anyway, I got the new o-rings and immediately noticed a big difference in the thickness. I had no trouble pulling the cylinders back off and swapping the o-rings. Putting the cylinders back on was even easier the second time...maybe because I knew what I was doing this time? Nah, probably because the piston rings had been compressed in the cylinders for a week already, and were much more willing to slip into the cylinders this time! Instant gratification - the cylinders now fit snugly against the engine case! Now it's off to go meet Ted (oupa) and swap some parts. I'm going to be needing a cylinder head here soon...
 
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