Project: 1987 Honda CH150

Discussion in 'Battle Scooters' started by Nihon Newbie, Dec 13, 2012.

  1. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    So stoked with my pile of tiny Honda parts, and materials for the rebuild!!! A local automotive shop let me use their impact screwdriver to remove the seized Phillips head screws anchoring the stator and failed pulse module, which was my last issue of disassembly. Big thanks to them! :D

    Lapping compound, sheet gasket material, Xacto knife, Hondabond, new piston rings, new cylinder, pulse module, new wrist-pin circlips, new exhaust gasket, new exhaust nuts, new base + head gaskets, new SS fasteners for the stator anchors, and clean gloves, lol!

    First thing, I need to verify the fitment of the new cylinder and gaskets. Next, I'll need to start tracing and cutting gaskets for the CCT, and the stator/pump cover. Tomorrow I'll be removing/cleaning the stator, then swapping it and the pulse module into the replacement stator cover with the new fasteners. After that, I'll start the valve lapping process, wash out and dry the head again, reassemble the cylinder head, and maybe if I have time, start stacking parts to work out the squish with the new gaskets, ensuring that everything is stacking up properly.

    The valve lapping suction handle thingy is way too big for these tiny valves, so I think I'm going to stick a piece of plastic hose on the end of the valve stem and just spin and pull from the other side, by hand.

    I'm still researching 2 things: a) if I'm supposed to apply anything heavier than motor oil to the valve stems/guides when I put the head back together and b) how best to clean, flatten, and prep the gasket mating surface on the head...

    Lastly, what say you all about re-using the original cylinder? I don't have a bore gauge, so I'm not sure on its exact ID at the moment, but I'm tempted to keep this brand new cylinder as a spare, and re-sell it whenever I sell the scooter. It has 19,000 miles on it, and looks to be in pretty good shape.
    #21
  2. Warney

    Warney Been here awhile

    Joined:
    Jun 6, 2010
    Oddometer:
    568
    Location:
    Omaha, Ne
    #22
  3. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    Ha! I watched that same video earlier. I've been on Youtube most of the day going between watching F1, and researching all the stuff I need to do to my engine. So awesome being able to look and watch people doing it, instead of just reading about it.

    News: My cylinder showed up in the mail today, but unfortunately, it is not an OEM part. This was not made clear in the listing, so I'm pretty pissed. I suppose I could re-sell it, but since it's not a factory-available part anyway, I guess I'm back to square 1 on the head gasket dilemma. The one that came with the eBay cylinder is of very different construction from the one I pulled out of the motor. There is no lip that seats down into the coolant jacket, and there is no fiber layer on the outside whatsoever. I'm not one to deal with parts misrepresentation lightly, so I'm kind of freaking out again.

    I guess I'll be back in contact with Gaskets to Go over in Thailand, as I have read about many a satisfied customer of his, after they had him custom make 1-off head gaskets for their bikes...

    I was so stoked earlier, thinking I would be riding this weekend...:becca
    #23
  4. Warney

    Warney Been here awhile

    Joined:
    Jun 6, 2010
    Oddometer:
    568
    Location:
    Omaha, Ne
    Contact Jack at jacksscootershop.com, he is a good fellow who may be able to get you fixed up.
    #24
  5. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    Thanks, I'll definitely give that a shot tomorrow. :1drink
    #25
  6. bykpimp

    bykpimp Live and let ride

    Joined:
    Oct 18, 2006
    Oddometer:
    1,410
    Location:
    Santa Cruz Ca
    This is a neat thread!!! I was working for Honda when these scooters were new and it brings back some great memories!!! I've got my ole CH150 Deluxe (forgets year, 85, 86? ) sitting covered up out in the drive. The exaust gasket thing brings back memories. 9 out 10 were missing when these scooters came in for a service. Love the pics in this thread as well!!!
    #26
  7. _cy_

    _cy_ Long timer

    Joined:
    Sep 25, 2011
    Oddometer:
    6,468
    Location:
    Tulsa, Oklahoma
    got two CH150 or CH125 parts scooters. both has complete engine/tranny, wheels, etc. let me know if you get stuck and need something
    #27
  8. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    I cut out some new gaskets for the CCT and the stator cover, though I only made the stator one as a template to send off if I ever need the gasket actually made, as it would have to be heavier duty than this thin fiber paper stuff. I only need to cut out one more, for the base of the new cylinder. I guess after I have the head machined, I'll try using the MLS head gasket that the cylinder came with...I also removed and cleaned the stator itself, before swapping it into the replacement case cover, then I did a final clean and lube of the water pump impeller shaft and its bearings. Learned a valuable lesson about why you shouldn't use anything but snap-ring pliers when removing snap rings...

    I spent a whole day on the head last week. Really hard to get any decent pictures, but I "ported and polished" it. I sanded the intake and exhaust runners, removing the fat lips of aluminum casting flash where the runner meets each valve seat ring, as well as smoothing the walls of the chambers. I polished the domed part of the inside of the head, as well as lapped the valves. Now I need to file down the welds on the muffler from when I repaired the break, have the head milled flat, and install my new valve seals, which unfortunately won't be here til January 4th. :/ Theoretically, after that, I should be a go for reassembly of the whole scooter. I'm thinking I'll run it for a day with the first oil change, drain it, fill it up again, and maybe run that second oil fill for a week? ...Thoughts on that?


    That's awesome! I think I would love working for Honda. This is definitely my first experience with all this gasket nonsense, both for the head and for the muffler...It's definitely a heck of a lot of work to be putting into something this old, but it's a great learning experience!

    Thanks so much,I'll definitely keep that in mind!:beer
    #28
  9. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    So, I took the cylinder head to an engine builder in town...The owner is a bit crazy, but still a sharp machinist. He spent a while looking it over and checking for warpage across the deck...I started getting nervous, then after a very, very long conversation about RA finish levels, and gasket composition, he declared it was just fine, and in no need of being machined! Didn't want to charge me for his time, said come back if I ever needed anything down the road. Super stoked on all this. :D

    Not stoked on still having to wait another week for my stupid backordered valve stem seals...ha
    #29
  10. tcjames.yu

    tcjames.yu Adventurer

    Joined:
    Jun 21, 2009
    Oddometer:
    49
    Location:
    Taiwan, Scooter's country
    I rode through Xindian Taipei today, sunny day.[​IMG]
    #30
  11. Wentwest

    Wentwest How's that work?

    Joined:
    Feb 19, 2007
    Oddometer:
    726
    Location:
    Northern California
    When I work on the deep mechanicals of a Honda Elite I'm impressed by the quality of workmanship and materials in these places where no customer was ever expected to go. The plastic body parts are fragile and get pretty worn looking with age, and they are not durable, but the serious machinery is really top grade. When you compare the original parts with Chinese reproduction mechanical parts it can be pretty shocking.

    That's why I keep working on these old scooters. They are worth the effort.
    #31
  12. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    I couldn't agree more! Even with 19k miles, and who knows what kind of maintenance before I bought it, I have been continually pleased to see that Honda really put some effort into building a lot of quality into this motor. Same story with my other Hondas, too. :D
    #32
  13. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    Valve stem seals finally arrived! So stoked. Tomorrow I get to put the head back together, and start reassembling the motor! :D
    #33
  14. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    Good news: I got the cylinder head put back together with new valve stem seals, piston installed with new rings, and all my new gaskets cut and ready.:D

    Bad news: It seems the bore on the aftermarket cylinder I was sold is undersized, by about .024" which is a hell of a lot...Seems odd that everything else about the part is bang on, but they failed to nail the most important spec of all. :(

    Going back to the engine builder tomorrow to see if he can either bore the new cylinder to fit properly, or hone the old one so I can re-use it...
    #34
  15. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    Since I live in a pretty small town of about 14,000 people, I assumed there wouldn't be anyone here in town who could do the cylinder, but I was wrong, ha! The engine builder I've been talking to recommended an automotive shop here in town, half a mile from my freakin house, lol!

    Dropped off the old one to be ball-honed. They'll check it with the bore micrometer to see if the ID is within spec, after the hone, then I should be good to go put the whole bike back together.

    Unfortunately, there are no returns on the eBay ripoff cylinder, so I'll have to either re-sell it as the wrong size, or pay to have it actually re-bored to proper spec, then sell it or keep it to be sold along with the scooter.

    Anyone want that new cylinder?? :D
    #35
  16. baloneyskin daddy

    baloneyskin daddy bikaholic

    Joined:
    Oct 21, 2009
    Oddometer:
    2,177
    Location:
    southcentral PA.
    Just to save you from a small hassle, for some reason it seems ,at least on mine, that the exhaust doesn't seal correctly unless I use 2 gaskets. Maybe the new oems are thinner but I've been thru this twice now and for 4bucks I just buy another gasket. It sounds alright when you fire it up but on deceleration it would pop.
    #36
  17. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    Thanks for the tip! That area will still be a major concern of mine when I get this thing running later this week. I put a weld bead around the base of the flange part that fits into the head, hoping it would give that sliding collar more leverage to hold it ll in place, so fingers crossed, there.

    I only have the 1 factory gasket, and I guess I should have ordered a few when I bought this one. Oops. I'll see how it works with one, then see about trying your trick if I have any trouble.:beer
    #37
  18. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    Cylinder took an extra day, but the hone worked out great, still well within spec on the ID, and it scrubbed up pretty well, too.

    I finally got to start the assembly process today, and put in 7 hours. Re-stacked the motor, new head gasket installed, motor back into the frame, all hoses and wires hooked up, except for the fuel tank. Adjusted the valves, put fresh oil in the engine, and decided to call it a night, praying that all my 200 hours of work won't be for nothing come test time tomorrow...

    Tomorrow I need to hook up the fuel tank, fill the coolant system, file down all the welds on the muffler, install the muffler, and connect the freshly charged battery. Then I can test start it, and see what kinks may need to be worked out. My biggest worries are the new head gasket, and the water pump. Fingers crossed! :uhoh
    #38
  19. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    Well, the scooter is back together! :D

    Spent a couple hours filing down the welds on the muffler, namely the restricting factory welds right where the end collar attaches to the head pipe. All sanded smooth now, and installed with the proper exhaust gasket. The only bad thing about the day, besides the rain, was that one of the 2 threaded exhaust studs spun in the head. :bawling: It holds the muffler just fine, but if I ever have to back that acorn nut off...I'll have another project.

    Motor started up just fine after I rolled the bike out of the garage. A little smoke from the exhaust, but runs smoothly. Can't tell if the small differences I notices on the short test ride were all in my head, but the throttle response feels smoother and more urgent than before. Less squeaking, too, ha.

    Hopefully the rain will be gone by monday and I can take it out for a longer shakedown ride and grab some better pics.

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    Scrubbed the outside of the motor so it would be easier to spot any possible leaks later on. Safety wired the acorn nuts so I won't lose them again. MLS head gasket seems to be working fine so far, thank God.
    #39
  20. Nihon Newbie

    Nihon Newbie Been here awhile

    Joined:
    Dec 13, 2012
    Oddometer:
    192
    Location:
    SLO Cal
    Well, the thing runs great, and displayed no signs of trouble after the 25 mile shakedown ride yesterday. Today, however, I took the bodywork off and noticed that the head gasket is weeping a little, and the cases are leaking a little oil. Can't see where from, so I'm pulling the motor out again tomorrow to try tightening the head bolts, and fix the oil leak. :cry
    #40