Wednesday, March 2, 2011

There’s nothing so sweet as the sound of a running engine….

Especially when it was torn down to the cases just two days ago.
Some of you may recall that I purchased a 1982 Honda FT500 Ascot last January for the missus. (Link here.) Well as with any 30 year old motorcycle, it had some issues, not least of which was a minor oil leak around the rocker cover. So one of my winter projects was to fix the leak.
On this model, the rocker cover is precision machined to fit on top of the cylinder head without a gasket. The oil up there isn’t under any pressure, so a good clean fit with properly torqued bolts usually does the trick. But not when the bolt holes have been stripped.
Of 11 bolts that hold the rocker cover in place, 9 had been stripped. Of those 7 had previously been heli-coiled, of which 5 of the heli-coils had also been stripped. So basically, if I had been able to do so, I could have turned the bike upside down and given it a good shake to have the rocker cover simply fall off. Now I knew why the previous owner (the so-called motorcycle mechanic!) had been reluctant to fix the oil leak – although, to his credit, he did advise me of it during the negotiations. So I guess it’s really my fault for not digging further into it at the time. (Another lesson learned, belatedly.)
So I was faced with drilling and re-tapping all those bolt holes 2 sizes over, which is not only a pain in the ass to do, but in a couple of cases would end up making the walls really thin. But then I remembered that the bike came with most of a spare engine, which was spending the winter out behind the shed, covered in snow. I went and dug it out and dragged it into the shop to thaw. And to my great delight, when I removed the rocker cover, the head had not been similarly butchered. So a quick swap of the cam and a couple of other bits and I now had a good head to work with. From there it was easy to bolt it all back together and fire it up. Now it runs great in the garage and I’m just waiting for the roads to clear for a final road test. I’m pretty sure I didn’t see any leaking oil (although the exhaust fumes were thick as a London fog when I was running it up to temperature inside the garage) so I’m hoping it’s good. But for now it’s done, and I can get on to the next project.

10 comments:

  1. I love working on engines! done a bit of heli-coiling too thanks to people who think that a torque wrench is a ratchet with a 6 ft piece of pipe on the end. Great for you to have a spare. Photos of the finished article when the weather improves please!

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  2. Geoff - Perhaps a skills test should be required before anyone can buy a set of wrenches.

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  3. I can do body and paint. Wish I knew WTF I was doing on my Harley motor. Would/Could save me some bucks.

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  4. It's always great when you can do the job yourself, saves lots of money ;-)
    I've to do my sons rear brakes this weekend, replace calipers, pads and maybe rotors, Pepboys quoted him $700 :-0

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  5. Dear Canajun:

    I'm sorry I didn't know you were working on this. I would have dropped by, parked my ass in the comfy chair next to the stove, drank your beer, and offered useless assistance. Next time.

    Glad you got a break on the covers.

    Fondest regards,
    Jack • reep • Toad
    Twisted Roads

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  6. Mr. M. - And I could say the same. Wish I knew how to paint. But that's why the barter system works so well.

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  7. George - As long as no custom tools or special machining are required it nearly always pays to do it yourself if you can. But having a competitor's quote does somewhat limit how much you can charge your son.

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  8. Jack - That's a very kind offer. Next time I need some useless assistance I'll be sure to call you... and stock up on weak beer.

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  9. Holy jaw-dropping hell! What kind of maniac ape got a hold of your bike? I have to admit, I snapped a rocker cover bolt (aluminum) off in my early days of motorcycle repair. I learned from my mistake and never repeated the offence. 9? Dammit. Wow.

    It is the mark of an insane man to repeat the same action and expect different results.

    Brady
    Behind Bars - Motorcycles and Life
    http://www.behindbarsmotorcycle.com/

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  10. Brady - I did a bit of research (after the fact, of course) and found out that there had been 18 registered owners of this bike! So plenty of blame to go around. I expect the real story was successive owners deciding the way to fix the oil leak was apply more torque to the rocker cover bolts - with predictable results.
    Anyway, it's now good, and the next owner won't have to worry about it.

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