Author Topic: Engine full of fuel and seized up  (Read 17777 times)

Offline PJM47

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Re: Engine full of fuel and seized up
« Reply #105 on: October 10, 2020, 04:41:15 PM »
What's this circled in red? (It could be something or nothing, difficult to tell on my phone)

Just a bit oil, cleaned off and there's nothing there.

Offline PJM47

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Re: Engine full of fuel and seized up
« Reply #106 on: October 10, 2020, 04:48:30 PM »
All gears and teeth are fine.

The conrods don't look obviously bent but I guess it would be difficult to tell.
It is tighter when pistons 2&3 are down (compressed) and fairly loose when they are the way out.

So can I get to the pistons / conrods without opening the top end or is it now major strip down?


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Offline PJM47

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Re: Engine full of fuel and seized up
« Reply #107 on: October 10, 2020, 04:49:59 PM »
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Online Johnwebley

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Re: Engine full of fuel and seized up
« Reply #108 on: October 10, 2020, 04:55:56 PM »
Have you got the head off?

Or the cam off?


If not. That may be the reason it is  difficult to rotate.

The cam opening the valves

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Re: Engine full of fuel and seized up
« Reply #109 on: October 10, 2020, 05:04:33 PM »
If you want to lift the crank out you can remove cam and rockers to let the cam chain drop down to crank,  then undo conrods/ big ends and lift crank out

You dont have to disturb the barrels and head at this stage.


Offline PJM47

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Re: Engine full of fuel and seized up
« Reply #110 on: October 10, 2020, 05:43:25 PM »
Cam and head still on. Haven’t touched the top end at all. I’m a bit reluctant to take things apart unless it’s really necessary, so was trying to establish what is normal and what is sensible to check for at this point.  The more I take apart the more I can check but also the more chance of things going wrong/me failing to put it back together properly :)
Is there any fairly non intrusive checks I can do? Would it be silly to put it back in the bike now?

Offline Nurse Julie

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Re: Engine full of fuel and seized up
« Reply #111 on: October 10, 2020, 05:54:51 PM »
No point in putting engine back in the frame yet, you haven't really diagnosed the problem yet. It would be such a shame and a pain to have to take it out again.
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Offline PJM47

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Re: Engine full of fuel and seized up
« Reply #112 on: October 10, 2020, 06:12:39 PM »
Yes absolutely, but do we know there actually is a problem now?

Offline philward

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Re: Engine full of fuel and seized up
« Reply #113 on: October 10, 2020, 06:56:09 PM »
Been following this thread and all the experts views - I would go for a full strip (I know its not what you want to here) - I think hydraulic lock damage - piston/rod - needs to be eliminated
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Offline Bryanj

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Re: Engine full of fuel and seized up
« Reply #114 on: October 10, 2020, 07:19:12 PM »
Sorry its got to come apart, there should be no difference 1&4 moving and 2&3 moving

Offline SteveW

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Re: Engine full of fuel and seized up
« Reply #115 on: October 10, 2020, 07:21:36 PM »
I don't know if this is even possible but could the cam have sheared in two?

So if only a part of the cam is turning you could get more than one compression stroke at a time and therefore way more difficult to turn engine?

As I said I don't know if this is even possible but a mate of mine did have a cam shear in two in his car once.
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Offline Bryanj

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Re: Engine full of fuel and seized up
« Reply #116 on: October 10, 2020, 07:26:28 PM »
Yes its possible and yes it has happened on other bikes before

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Re: Engine full of fuel and seized up
« Reply #117 on: October 10, 2020, 07:31:25 PM »
Inspection of cam is easy,  just remove cover as it is just that "a cover" and disturbs nothing.

Offline PJM47

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Re: Engine full of fuel and seized up
« Reply #118 on: October 10, 2020, 07:57:54 PM »
Ok will have a look at that next.

Offline PJM47

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Re: Engine full of fuel and seized up
« Reply #119 on: October 11, 2020, 09:33:16 AM »
All looks ok under the rocker cover.

Cam out and head off next then. I'll read the manual, but any top tips I should be aware of?

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