Engine full of fuel and seized up

[McCabe-Thiele (Ted)]

Having followed this post with interest I am none the wiser yet as to what the cause was - have I missed something?

[PJM47]

Having followed this post with interest I am none the wiser yet as to what the cause was - have I missed something?

No I'm not sure I am either. Like I say at the start of this page once the starter gear was removed everything freed up. Putting it back on and everything is still free, the crank spins nicely, even keeps turning on its own with a push, I could barely move it before. Putting the rods back on as Trigger suggested and it still all turns nicely.

As I say my only concern was I'm not sure if that gear is mean to be able to move latterly on the shaft a bit which it does now. I have nothing to compare it to and nothing looks wrong.

I'd have been much happier finding something broken but not sure what else can be done.

[Bryanj]

Put the alternator rotor on temporarily(i.e. bolt not tight) then see if it wobbles when crank is spun, i have seen the taper end bent

[PJM47]

Put the alternator rotor on temporarily(i.e. bolt not tight) then see if it wobbles when crank is spun, i have seen the taper end bent

No wobble. Checked with fixed point on the case, not that accurate, but nothing obvious.

[royhall]

Like I mentioned at the start it was probably that the petrol washed every bit of lubrication out of the engine and made it impossible to turn. Now it's re-olied everything is fine. But ensure on reassembly that every single part is cleaned and oiled and carefully checked.

[PJM47]

Note it was definitely the starter gear that was the problem, then crank was in and out several times and fully oiled and nothing else connected, it was just resting on the bottom shells but it still would not turn freely. On one of the occasions of taking the crank out the starter gear came loose a bit and then everything was instantly fine after that. Still seems very odd to me.

[PJM47]

so most bits on order now (ouch).

Without wanting to start too much of a debate what's the best / recommended sealant for the bottom end? I've seen other posts but not really a conclusion.

Honda Bond, 3 Bond , Yam Bond etc for crank case halves only. The lightest, lightest smear, so light, you can almost see through it.

Thanks, blimey Honda bond 4 is reassuringly expensive isn't it. Don't want it leaking though.

[Bryanj]

Only thing i can think of is the bush in the big gear is worn and allowed the gear to cock sideways, could be worth checking play to crank.
Sold a nos one to the states last year!

[royhall]

Trying to turn a locked engine on the starter has probably knocked it out of line.

[PJM47]

I sssume that bush is not replaceable?
I wonder if the bush has pushed in/back slightly under the stress allowing the gear to move further up the shaft than normal and hitting the case and also getting stuck? On the plus side at least the gear can be replaced after the engine is back together.
First pic is mine, secon pic is a used one on eBay.


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[allankelly1]

Hi

Looks like a glacier bush to me

I have changed these on my RD350LC kick starter idler and the clutch centre bush so could be well worth while if it’s shot pressing it out and getting a size and asking a local bearing supplier if they could supply a new one






As then the bush and gear would be as good as new


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[PJM47]

Hi

Looks like a glacier bush to me

I have changed these on my RD350LC kick starter idler and the clutch centre bush so could be well worth while if it’s shot pressing it out and getting a size and asking a local bearing supplier if they could supply a new one

As then the bush and gear would be as good as new


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Interesting thanks. I will look into it.

[Trigger]

That bush looks ok. But, always worth measuring it up

[royhall]

Note it was definitely the starter gear that was the problem, then crank was in and out several times and fully oiled and nothing else connected, it was just resting on the bottom shells but it still would not turn freely. On one of the occasions of taking the crank out the starter gear came loose a bit and then everything was instantly fine after that. Still seems very odd to me.

Looks like you found the smoking gun then. The wheel should not have been stuck to the crank it should be free to rotate. Amazing what lack of oil does to an engine. It is free to slightly move on the boss and is fed by pressurised oil to the bush and to behind the wheel through a feed hole. Make sure everything is straight before reassembly as those starters on a good battery put out a lot of torque.

[PJM47]

Yes hopefully that’s it. Evetthing else seems nice and straight and in good condition. Just waiting for all the bits to arrive. New cam and primary chains and tensioners. New seals everywhere new piston rings. And I’ll do the valve guide seals and lap. Should be a nice little overhaul for it anyway.

Do we think I need to give the cylinders a light hone to put cross hatching back to settle in the new rings or is best to leave as is?