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Found this in my oil pan!!

PostPosted: Sun Apr 22, 2012 7:35 pm
by 79cbx
I found this pin in my oil pan (79 cbx.) Can anyone tell me where it's from and do I need an overhaul now? I've just had this bike for a short time and I'm not to positive on the history of the bike.

Jerry

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Re: Found this in my oil pan!!

PostPosted: Sun Apr 22, 2012 8:46 pm
by Jeff Bennetts
Looks like the internal clutch actuating arm pin but theres no reason for that to be in the pan, I'd have to go measure one to be certain, let's see what the rest of the guys say, what's it's diameter?

Re: Found this in my oil pan!!

PostPosted: Sun Apr 22, 2012 11:44 pm
by bobber01
Appears to me to be the bottom locating pin for cam chain guide.

Re: Found this in my oil pan!!

PostPosted: Mon Apr 23, 2012 12:04 am
by 79cbx
The pin is about 6mm in diameter and 35mm in length.

bobber01 wrote:Appears to me to be the bottom locating pin for cam chain guide.


I kinda thought it may have been that pin also after looking at my repair manual. Is that pin used to secure the cam chain guide?

Jerry

Re: Found this in my oil pan!!

PostPosted: Mon Apr 23, 2012 9:24 am
by Jeff Bennetts
bobber01 wrote:Appears to me to be the bottom locating pin for cam chain guide.



That makes more sense. :text-goodpost:

Re: Found this in my oil pan!!

PostPosted: Mon Apr 23, 2012 11:52 am
by 79cbx
Any adverse affects in not having this pin installed???

Jerry

Re: Found this in my oil pan!!

PostPosted: Mon Apr 23, 2012 12:28 pm
by bobber01
79cbx wrote:Any adverse affects in not having this pin installed???

Jerry

I wouldn't run the engine without it. Cam chain tension will be affected and also allow guide to 'bounce' on the bottom due to nothing securing it, allowing it to weaken and break. Then chain may jump cam gear teeth causing some major valve/piston top damage at the minimum. Get head/base gaskets and re-install. Shouldn't have to totally pull engine (tilt forward). If all it needs is the pin re-installed, a days work. But I would source a cam chain guide as I suspect its been damaged.
Just checked an engine I have apart and the dimensions you provided match that pin.

Re: Found this in my oil pan!!

PostPosted: Mon Apr 23, 2012 1:45 pm
by 79cbx
bobber01 wrote:
79cbx wrote:Any adverse affects in not having this pin installed???

Jerry

I wouldn't run the engine without it. Cam chain tension will be affected and also allow guide to 'bounce' on the bottom due to nothing securing it, allowing it to weaken and break. Then chain may jump cam gear teeth causing some major valve/piston top damage at the minimum. Get head/base gaskets and re-install. Shouldn't have to totally pull engine (tilt forward). If all it needs is the pin re-installed, a days work. But I would source a cam chain guide as I suspect its been damaged.
Just checked an engine I have apart and the dimensions you provided match that pin.



Thank you very much for the reply. :text-thankyouyellow: Looks like a top end job is instore for me as this bike has kinda low compression anyway. :(

Jerry

Re: Found this in my oil pan!!

PostPosted: Mon Apr 23, 2012 5:44 pm
by daves79x
I'd make absolutely sure that's the pin before tearing down the engine. I don't have one out close by to verify, but it is impossible for that pin to 'jump' out, unless the trough it runs in has broken out and if that's the case, you'd have a lot more metal in the sump. As Jeff said, it might be the clutch pin, but then you'd not have the clutch operating if it was missing. If it is the tensioner pin (and it sure looks like it), perhaps someone thought it was installed properly, but it popped out during assembly and has been laying in the sump ever since. If so, the bike has run since then without it. So if it is for sure the pin for the tensioner, I'd be tearing it down to replace. You can do it without removing the engine. This is a good reason to check the sump frequently after an engine rebuild - lots of critical stuff has been found there that had been installed incorrectly during a rebuild.

Dave

Re: Found this in my oil pan!!

PostPosted: Mon Apr 23, 2012 6:35 pm
by Jeff Bennetts
I think bobber nailed it Dave, looks like the cam chain tensioner pin, I couldn't tell by looking at it on this IPad but once he posted the dia it sealed the deal. When you have a thirty year old bike who knows how many PO's it's had or what the heck they have been up to inside a motor.

Better takes Dave and bobbers advice and pull the top end off to make sure the boss for the pin hasn't been damaged or some kind of Jerry rigging went on in the tunnel.

Can you get your hands on a flexible mini scope? the only other way I can think of inspecting for damage.

Re: Found this in my oil pan!!

PostPosted: Tue Apr 24, 2012 6:08 am
by 79cbx
Thanks for the reply Dave. Yes, I too would like to know for sure that is the pin before I tear into it. I don't have access to a scope unless I buy one but I wouldn't know where to get one. The story I got from the previous owner who said he got the bike from the original owner who had it rebuilt after a hydro lock/ bent rod. The previous owner said he put about 2k miles on it. I've put about 300 on it. I didn't think the top end noise was too excessive. Which makes me wonder if it is that pin. But this is my first cbx and maybe I just don't know if the valve noise is excessive. So, if I do get a scope and look up past the oil pump, would I be able to see if the pin is there if the boss area is still intact? Seems like I would still have doubts if the pin is actually there if the boss area is good. There wasn't anything else in the pan. No metal chips/shavings at all.

Jerry

Re: Found this in my oil pan!!

PostPosted: Tue Apr 24, 2012 6:48 am
by Rick Pope
If the engione was re-built, it could be a pin that someone dropped, and your tensioner could be fine. I'd try finding a scope first and have a look.

I think Milwaukee tools has one for a reasonable amount of $. Might be as cheap as a set of gaskets and a days work?

Re: Found this in my oil pan!!

PostPosted: Tue Apr 24, 2012 10:38 am
by Jeff Bennetts
I wonder if you could rent a scope? It's certainly a possibility someone dropped that in there. I'm 99 percent sure it's a cam tensioner pin, I went out to my shop and measured one and it coincides with your measurements.

Re: Found this in my oil pan!!

PostPosted: Tue Apr 24, 2012 4:43 pm
by 79cbx
Thanks for all your help fellas. I will try to source a scope to see what I can see. 8)

Thanks again...you people are very helpful in ones time of need. :dance:

Jerry

Re: Found this in my oil pan!!

PostPosted: Tue Apr 24, 2012 8:18 pm
by steve murdoch icoa #5322
Harbour Freight sells a couple versions of inspection cameras, one for $100.00.
The reviews seem to be 50/50 as to whether it is junk or not.
http://www.harborfreight.com/digital-in ... 67979.html