The International CBX Owners Association

Hi Mike

Your summary re the problem is close enough, but there was a fatal detail which caught me out 100%.

THE TOP CRANK CAP HOLES ARE NOT BLIND. THEY ARE CONNECTED TO THE OIL GALLEYS*.

After the blasting, the cases were meticulously cleaned internally, and well enough (he thought ...) externally.
I never paid enough attention to these two holes, ASSUMING they were blind as many external holes are.
In my case they further 'seemed' blind as they their bottom was filled with sealant which resisted my air and water guns.

At the time I stupidly, missed the hint offered by Honda putting an o-ring around these screws, clearly shown in the parts catalogues ... but there you are

Had I realised this little-known fact, maybe the problem would not have happened. Regardless, I do agree glass blasting cases or even complete engines is a stupid idea, which however is quite common in the UK!!

I have now cleaned and re cleaned theses holes. However, when time comes to prime my newly rebuilt engine, I will leave the two crank caps out for a minute or so to get new oil pumped out of these two holes, further cleaning them, in case anything is left in them (which I doubt).

In any case and under normal servicing, these holes can get very dirty. Also I know of many people who drill and helicoil these as they are quite prone to stripping.
Chaps, beware of what ever is there after a long service life, or you inadvertently put there e.g. after helicoiling, as they are not as innocent as they look!

Best, Aris

*From data I have gathered in the last few months by asking around, in some engines these holes are blind, is some partially open, and in my case, the one on the left quite open (and hence the problem with rods 1 & 2) and on the right almost closed hence my no 6 rod staying healthy .

My apologies Aris...... I'm a bit confused as your comments go back and forth to sometines contradict one another. I am unable to put your thoughts together that make sense...........so I will comment on each of your statments.

>>The top crank holes are not blind.....they are connected to the oil galleys.
Something normal and to expect....no ? Normal oil feed to the crank.

>>I never paid enough attention to these two holes, ASSUMING
>>they were blind as many external holes are.
Yes..... I understand on might assume some holes are blind, or blocked off after their purpose (cross-drilling to allow access to holes that need to be drilled) is no longer needed.

>>In my case they further 'seemed' blind as they their bottom
>>was filled with sealant which resisted my air and water guns.
>>At the time I stupidly, missed the hint offered by Honda putting
>> an o-ring around these screws, clearly shown in the parts
>>catalogues ... but there you are

So Honda used "O" rings to seal off these holes that would feed oil to the crank ? How does this make sense ?

>>.. when time comes to prime my newly rebuilt engine, I will leave
>.the two crank caps out for a minute or so to get new oil pumped out
>>of these two holes, further cleaning them, in case anything is left in
>>them (which I doubt).

How can you do this with the engine cases together?
The crank caps are inside the engine.


My best....... Mike

Mike Cecchini wrote:>>The top crank holes are not blind.....they are connected to the oil galleys.
Something normal and to expect....no ? Normal oil feed to the crank.
Mike

Mike, read title carefully: Top crank CAP holes are not blind ...

The drawing below should clarify further: I was always referring to the hole pointed to with the green pointer (there are 1 either side of course) and the screws & o-rings pointed in red (nos 20 & 16 in the drawing)
The CRANK CAPS themselves (nos 2 in the drawing) are pointed to with orange pointers
Hope this clarifies everything.

Best, Aris

Ahhhhhhh.......said the blind man.
Picture worth 10,000 words.

How long before the majic moment of engine start-up ?

Fingers crossed for no suprises, knocks, taps or odd noises.

It should be quiet as a mouse with just the pistons swooshing up/down and a little clutch sound.

My best.........Mike

Amen brother!

Off for a short, late summer holiday.
Then the late night candle will be on overtime until the magic moment (or two).

Best, Aris

Kool_Biker wrote: Top crank CAP holes are not blind ...

Best, Aris

Aris: if you ever worked on the motor and turned it on the nut under the cap, you would see quite some oil squirting out of the hole, another indication, besides the O-ring that there is a connection to the oil gallery. An annoying side effect of performing this operation.
However, I don't know that I would have made the connection and take care of it properly, if I would have been in your place.
Some things just happen. That's why new vehicles have a warranty

Mike Cecchini wrote:
How long before the majic moment of engine start-up ?

Fingers crossed for no suprises, knocks, taps or odd noises.

It should be quiet as a mouse with just the pistons swooshing up/down and a little clutch sound.

My best.........Mike

All, after ~114 days of lows (too many) and highs (quite a few), my long suffering engine is at last repaired (he thought), assembled, looking good and days from being put back on my Z.
I hope to be in a position to fire it up in about a week.
Please wish me luck
Aris

Fantastic.

N.

Aris, your engine looks like new. I'll be keeping it all crossed for you. Good luck!
Ross

WOW........what a beauty !!!

Aris, if you haven't started your engine, yet, you might check with Dave McMunn, or others, about those two screw holes. If they lead into a major oil galley, you might not develop any significant oil pressure to feed the crank bearings. Could be a bad thing. Without any other information, I would just remove the sparkplugs (to unload the starteer); and, crank the engine for 30 seconds, maybe less, to 'flush' things. While I'm not sure, there may be considerable oil discharge from those two screw holes. If so, you may turn the engine for less time. I say all this based upon the amount of oil that does discharge from the screw hole when hand turning the engine while setting valve clearances.

Good luck with the project. The engine looks beautiful!

Thank you all !
Aris

Larry Zimmer wrote:Aris, if you haven't started your engine, yet, you might check with Dave McMunn, or others, about those two screw holes. If they lead into a major oil galley, you might not develop any significant oil pressure to feed the crank bearings. Could be a bad thing. Without any other information, I would just remove the sparkplugs (to unload the starteer); and, crank the engine for 30 seconds, maybe less, to 'flush' things. While I'm not sure, there may be considerable oil discharge from those two screw holes. If so, you may turn the engine for less time. I say all this based upon the amount of oil that does discharge from the screw hole when hand turning the engine while setting valve clearances.

Good luck with the project. The engine looks beautiful!

Larry
I have spent so much time researching this.

I plan to fill my freshly rebuilt engine with oil, before I put on the two end caps and without plugs have it cranked on the starter, to get some fresh oil (if any) coming out of the infamous two holes.
Then, I will install both end caps ensuring each top screw gets its little seal and continue cranking for few seconds to build pressure on the installed pressure gauge.
After this, I will let the oil permeate the various bearing surfaces for about 24 hours (thanks for the tip Dave ; ), and only then fire the engine.

Cheers, and thanks for your wishes, Aris

Sounds excellent, Aris. We all enjoy reading your experience. Most educational, too. Thanks.

Off the engine stand at last , sitting again onto the bike lift with carbs installed. And the voyage continues ...
Aris