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Engine full of fuel and seized up

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PJM47:

--- Quote from: Trigger on November 03, 2020, 02:20:42 PM ---These should not leak if the studs are sealed and the O'rings are up graded  ;)

--- End quote ---


Trigger of you get a second would you be able to elaborate on what you mean studs are sealed? How would I do this? I have the upgraded O-rings now. Ta.

Nurse Julie:
The head studs that can leak are the ones that the towers slide over and they have a  M6 washer and M6 nut. If the stud thread is not sealed with thread lock, oil can weep down the thread to the spark plug area.

PJM47:

--- Quote from: Nurse Julie on November 06, 2020, 12:32:29 PM ---The head studs that can leak are the ones that the towers slide over and they have a  M6 washer and M6 nut. If the stud thread is not sealed with thread lock, oil can weep down the thread to the spark plug area.

--- End quote ---

OK thanks

PJM47:
Hi folks
I’m getting ready to put the engine back in, I thought first I’d hook up
the oil tank and try to see some oil flowing. But I am struggling to get pressure, I am turning it on the starter, as much as I dare not wanting to damage it, and all
looks good but I’m not seeing much or any oil get to the top end.
I’ve read this is not unusual with air locks in the pump. But I am not sure now whether to just put the engine back in the frame and sort it later or persevere with it on the bench. Opinions vary on what do.
I tried priming the pump but its not really possible with the engine vertical for access. I filled the oil gallery and that didn’t help, tilted it to the side, didn’t help.

Any thoughts appreciated.

MrDavo:
After a complete failure to get any oil pressure in my CB750K1 engine after I rebuilt it, a worried query on here sent me off to Boots to buy a tub of generic Petroleum jelly (it doesn't have to be Vaseline by brand).

I took the oil pump apart and packed it with the stuff, then tried again. Instant success! Oil appeared in the oil gallery at last, then in the cambox. I believe some old American V8s use the Vaseline technique as a matter of course to get their oil pumps started. The jelly simply dissolves into the oil, and wont damage or block anything. One wonders if Honda did something similar at the factory, I recall reading that they came primed with some sort of fishy oil that had to be replaced before use, the ex Honda workshop guys on here may be able to confirm that.

There was also a very sad thread on here from a member who put all his effort and money into a rebuild, then started his CB750 up without checking for oil pressure. the result was a beautiful rebuilt bike with a freshly ruined motor.   :( As I remember it he was too disheartened to pull the engine to do it all again, and sold the bike 'as is' for someone else to fix.

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