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Post by robinbanks on Nov 3, 2022 7:09:02 GMT
Welcome.
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Post by growntree on Nov 3, 2022 13:41:17 GMT
Welcome.
What is actually wrong with it? Engine seized? No spark? Carbs seized? As said previously, turning the engine over by hand is a good idea to start with. Left side engine cover off (you don't have to drain the oil first for the left hand cover, but worth a check of the dipstick to see condition and if there is any) and turn the flywheel anticlockwise. Cmsnl.com has the parts guide and exploded views.
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Post by johnjones on Nov 3, 2022 15:34:33 GMT
I assume you know how to check the oil level, but in case you don't ( wet sump like a car, unlike your dry sump British bikes ), with bike on centre stand on level ground, unscrew the dip stick, wipe and reinsert but don't screw in, remove and check oil level. It should be in the cross hatchings. Do not overfill.
Cam cover off ( first time remove HT coil and cdi black box ) to expose cam and valves...
A picture tells a thousand words so pictures of in there would be good at this stage.
The engine will run with the cam cover off but is messy due to oil feed and splash lubrication.
Flywheel cover off, plugs out, turn flywheel by hand ( anticlockwise Norman running direction ) to establish valves open and close properly. If engine appears to "lock" STOP, and check for increasing rocker to valve play/clearance. 250 5 inlet and 6 thou exhaust cold, 400 4 inlet and 5 exhaust cold. The valve faces and piston crown will be visible thru the plug holes.
Do valves open and close properly ?
Ohc chain driven. On the flywheel you will see an F and T. There is a pointer on the c/case about noonish. Notice the lines on the cam sprocket. At T the lines should be horizontal inline with the cam cover head sealing face.
Any line "lean back" ?
Much lift of cam chain from sprocket ?
To adjust cam chain ( you may as well do that now if all ok so far ), set to T, slacken the lower nut in the middle of the cam chain tunnel at the rear of the engine, did the rear cam blade move down ?
It's sprung loaded but can suffer from "Stocktion". Then nip the nut up and tighten ( only 6 foot pounds ! ) Do not ( DO NOT ) shear it's bolt.
See CMSNL exploded views for the chain arrangement.
Check valve clearances, if tight then adjust, if slack adjust. After the engine has run for a while you can revisit this task.
So, valves free and working properly, refit cam cover taking care the rubber seal is still in place, if your fighting it to get it off and on your doing it wrong, there is a sweet spot where it comes off and goes back on hassle free. Notice the two chromed cam cover bolts, do not ( DO NOT ) shear them off, 6 foot pounds max.
If the bike has a kick start, then you can now kick it over many times, if not you can use the starter motor.
Checking for spark, the cam cover is rubber insulated !
Red neons plug caps are really handy and will pay for themselves the first time used. They fit inline with HT cap and plug but you will have to make and adapter...they flash when ht passes thru them. This is the safest way ( apart from finger test ) to check for spark, the system is a bit fragile.
Alternatively if you have a welder or can thread a hole in some metal, arrange for two old working spark plugs to be attached to said metal bit, which has a flying earth lead.
Wasted spark ignition system, both plugs spark at same time once per revolution.
Cdi does not require a battery to work,it's a self contained system, a modern take on a magneto if you will. it works with a kick start, works better with the starter motor as cranking speed is higher.
Increased revs, increased rate of change, increased HT.
Enough from me for today got car work that needs to be done....
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Post by johnjones on Nov 3, 2022 15:37:12 GMT
Stocktion should read Stocktion. Stocktion Bloody hell it's sticktion
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Post by johnjones on Nov 3, 2022 15:40:18 GMT
Pictures pictures pictures, take your time and enjoy...
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Post by philsbury on Nov 3, 2022 18:48:40 GMT
Lets see what happens when I sort this Maybe what should be expected - but hope it sorts the battery drain Cheers, Phil
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Post by duffer on Nov 3, 2022 19:48:18 GMT
Blimey Phil, John has taken a shine to you. An absolute masterclass lesson in going over a long standing engine. Enjoy cleaning and fixing up the starter. I have a go at anything. I love the line from an old John Wayne film "You're not dead, till I tell you you're dead ".
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Post by growntree on Nov 3, 2022 19:55:01 GMT
Lets see what happens when I sort thisĀ Maybe what should be expected - but hope it sorts the battery drain Cheers, Phil Doesn't look too bad. Clean the contacts up towards the bottom with glass paper (don't use sandpaper as the bits of grit will come off into the motor), check the terminal has no continuity to the chassis (it shouldn't with that middle section taken out) and then stick it back together again. You may have to rearrange the washers so the end of the coil doesn't catch the brushes, push and pull on the shaft a bit while you turn it. Then positive to the terminal and negative to the body and it should spin.
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Post by philsbury on Nov 4, 2022 8:27:37 GMT
Still on a learning curve - and appreciate the advice being given. Thanks everybody Always prepared to have a go and pay the professionals when it goes beyond my ability Dont think it will be long before its running
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