Kawasaki Concours Forum

The C10, aka Kawasaki Concours - The Original => The Bike - C10 => Topic started by: gpineau on February 05, 2018, 09:42:50 pm

Post by: gpineau on February 05, 2018, 09:42:50 pm
I just bought a C10 to use as a parts bike but... its a shame to salvage it because it looks great and it is running.  When I start it, the bike idles good and throttles nicely.  But there is a knock coming from the engine.

Not sure its a rod yet but I will find out.

Here's my question: Can rod bearings be changed via access through the oil pan?  AND can the oil pan be removed while the engine is still in the bike?
Post by: tweeter55 on February 06, 2018, 05:23:12 am
I can’t comment on your questions but I have a couple observations. Check for hydralock and cam chain tension. I thought mine was knocking like a rod and it was the automatic cam chain tensioner not working as it should. Lots of good info on both subjects on the forum.
Post by: gpineau on February 06, 2018, 07:53:27 am
I just finished up a lot of top end engine work on my other Connie and experienced the cam chain noise. This newly acquired bike sound different than that.  I will check for hydro lock before doing anything else to the bike. 

My ears are telling me there is a rod knocking.  But if I use the screw driver to my ear to listen to different parts of the block, the noise does not seem to be coming from the crank case. Instead it seems to be coming closer to the transmission. All preliminary observations.  I have  spent less than 10 minutes with the bike. 

Can anyone answer my question?  Can you change rod bearing from the bottom? Can you get the pan off without pulling the engine? 

If the answer is no then I will start removing the parts I want and begin parting it out.
Post by: Daytona_Mike on February 06, 2018, 02:27:13 pm
The answer you want is Yes and No. it depends on which rod. Others can chime in and tell you exactly which rods can be changed without splitting the block open. 
So you need to figure out which rod bearing  is bad so we can tell you if it can be removed easily or easier.
Post by: gpineau on February 10, 2018, 10:55:24 am
I have taken most of the plastic off so I can get at the engine. Using my experience with automobile engines, here is what I have done so far to try to determine the problem.

I took the plugs out and checked each cylinder for play in the rod bearings.
 Cranked the engine by hand and got each piston on the down stroke, then pushed real hard from the top to  see if I could find some play. I could not detect any play in the rod bearings. 

I also pulled the plug wires one by one while the engine is running to see if the noise quit or got quieter. The engine slowed but the noise stays the same.  I am beginning to think it is not a rod but rather something in the top end.

Any old timers familiar with motorcycle engine noises please listen to this and give me your opinions. 


Post by: RFH87_Connie on February 12, 2018, 11:59:41 am
I had a pad on a rocker go bad and it sounded horrible.  It's the part that slides along the cam lobe.  It got louder and louder as time went by.  Put a new/used one in and it sounded fine again - no damage to the cams.  The cam chain tensioner (CCT) can also make horrible noises if it has slipped out of adjustment (meaning it unsprung itself).  The sound will usually be on the left side and echoes real loud in the faring if you are riding.  Take it out and inspect it.
Post by: gpineau on February 12, 2018, 12:32:41 pm
How did it sound. Like a knocking sound. 
I readjusted the valves because they wer too tight and had no clearance. It didnt help.
I also noticed that the "noise" was less when the valve cover was  off....or maybe my imagination.

listen to this at time 1:30  https://youtu.be/mec8aCRRl80  (https://youtu.be/mec8aCRRl80)   hear the knocking?

listen to the last minute of this. https://youtu.be/I7C84A7M7i8 (https://youtu.be/I7C84A7M7i8)  notice the knocking is not there with valve cover off?

Listen to this after valve adjust and valve cover back on..  https://youtu.be/-654FDkxbcQ (https://youtu.be/-654FDkxbcQ)  notice a clacking noise.

Isnt that weird. the is defiantly a clacking/knocking noise in the beginning. After adjusting the valves and running with the cover off the noise is gone. Sounds like a sewing machine.  Then when I put the valve cover back on the noise is back but not as loud as before.
Post by: RFH87_Connie on February 12, 2018, 12:47:53 pm
Mine developed what I would call a loud "clacking" sound.  It's hard to listen to a sound when you are not there, but that sounds a lot like it.  Mine got to the point where I could actually feel it in the handle bars and it started to make me cringe just taking it for a spin.  It had the sound like something was going to let go.  It came to the point where I had to find it, or get another engine.  Not that I can't, but I was not going to overhaul an engine.  It's way more economical on this bike to just find a low mileage used one and just swap it in.  I spoke with SISF about the sound and we discussed looking at the pad on the rockers.  I almost didn't.  Sure enough, it was right there.  Only one had it, probably not tempered to spec - luckily I had one laying around.  It doesn't take long to pull the rockers out - especially if you have the cover off already.
Post by: gpineau on February 12, 2018, 01:12:43 pm
Well I have put the cover back on now but I am getting really good at taking them on and off.
My other Connie had 2 bad rockers but it sounded different than this and it was easy to spot since there was a dropped valve and the cam needed to come out anyway.

But since I didn't see anything loose I didn't think to remove the cams and check for concave cam followers.

I will give them a look.  God I hope your right.
Post by: RFH87_Connie on February 12, 2018, 01:34:34 pm
Mine were not lose at all by hand feel.  They were still under heavy spring pressure.  I'm not sure if the sound is from no longer hitting the lobe right or that it is hitting something else from wear.  Maybe it's actually "floating" and hits each time the lob comes around and is smacked.  I'd have to study it again.

Just so you know, this was on a used engine I picked up.  Clacked as soon as I started it up.  Probably why the bike was parted out.  I originally thought I did a valve adjustment wrong, but discovered this.

Good luck!
Post by: gpineau on February 12, 2018, 05:57:08 pm
Just pulled the valve cover again in anticipation of changing the cam followers.

I ordered a whole set of rocker arms (followers) and they should arrive on Friday.

I need to know what size allen to use to remove the chain guard that goes over the top of the cam sprockets.  I know I had one cause I used it for my other Connie but now I need to go buy another one.

So I am back to working on my other Connie which developed a radiator leak last week.
Post by: gpineau on February 13, 2018, 03:22:17 pm
Today I got nothing to do after installing the repaired radiator in my other machine so I pulled both of the cams.  All the cam followers look good (normal but smooth wear) except number 3 intake. There is a quarter inch wide concave grove worn into it. It doesn't show well in the photos but you can definitely feel it with your finger.

It looks as bad or worse than the photo of the BAD one posted by RFH87_Connie.

I hope that is the noise source because I am running out of suggestions.
Post by: Daytona_Mike on February 13, 2018, 05:47:59 pm
Yup, that one would normally  make a loud 'Tack Tack Tack' sound
Post by: Kelly E on February 13, 2018, 08:32:23 pm
The same thing that happened to my bike except it was #4 exhaust that had the bad follower. I used the opportunity to install a set of torque cams. 8)
Post by: gpineau on February 13, 2018, 09:51:36 pm
Was it making a clacking  noise like a rod knocking?

The cams look to be in good shape. there is some pitting but the surfaces are smooth. I think I will live with just a set of followers. It was supposed to be a parts bike but I think it will make someone a good weekend rider when I am finished with it. 
Post by: Kelly E on February 13, 2018, 11:16:29 pm
Yep, a clacking noise that sounded like a rod knock.
Post by: RFH87_Connie on February 14, 2018, 05:47:13 am
You found it!  Put it back together and enjoy it!  Thanks again to advice and discussion from SISF!

I don't think there is any rhyme or reason to which position they are in when they wear because the part simply wasn't manufactured correctly (tempered).  The peps assembling them just grab a random set from a container and install them wherever they wind up.  Most of time 8 good ones were used during assembly.

P.S. - I know you said you bought a set, but I would just replace the bad one since you know the rest are unworn and still good.  Keep them in the exact same place also.
Post by: gpineau on February 14, 2018, 08:36:02 am
Good Idea. 7 of the followers have proven good for thousands of miles. Why take a chance on replacing them. I'll just change the bad one and have 7 spares.
Darn, its only Wednesday and the parts wont arrive until Friday. 
Today is supposed to be near 60 degrees outside. Maybe I will take one of the bikes for a spin.
Post by: gpineau on February 14, 2018, 03:50:40 pm
Pulled the intake followers today. The oil feeder tube is filthy. no wonder that follower failed. I am surprised that none of the others have not failed as well. Most of the feeder holes are so dirty you can see the sludge caked up inside the tube. I pushed a cotton swab through it and it came out black.

 I need to know is there an engine flush for motorcycles that everyone trusts as safe?

Post by: RFH87_Connie on February 15, 2018, 05:51:59 am
All my opinions and probably what I would do:

The oil tube, unless it was blocked, was probably not the real problem unless they're all bad.  It was still bad manufacturing.  I would just put fresh oil in it.  The C-10 has a wet clutch so anything you add will ruin the disks.  If you are that concerned you could remove a few of the supply lines and flush them out, but probably a waste of time.  I would just consider a little more frequent oil changes with a fresh filter each time for now.  If it was me (IMHO) I would use synthetic (and I do, Rotella-T6).  You can pick up the Walmart house brand or the better Rotella-T6 for a good price, especially since you might be changing it more frequently now (for a while).  Also, just a reminder, the C-10 has TWO drain plugs - not including the filter itself.

Since you are in there already, you may want to consider changing the thermo to make sure it is keeping the engine as hot as possible.  You can actually use one from a car.  Tell them you want one from a 1983 Honda Accord.  The model doesn't matter.  Get the 192 degree I think it is.  Order the O-rings from the local dealer or online (2 if I remember, a big one and a smaller one) for the housing before you start though as they usually dissolve into black bubble gum over time and you won't be able to seal it back once opened.
Post by: gpineau on February 15, 2018, 07:58:28 pm
Thanks everyone for all the advice and good suggestions.

Just buttoned it up. (except for the tank and seat.  Bad lifter did the trick. Sounds like a new bike. !!!

I just changed the one bad follower and left the others alone. So I have 7 back ups.

Decided against the flush. I am just going to change the oil with some really cheap  stuff and run it for a while then change it again.

This $300 parts bike just turned into a $2k Connie.

Thanks again guys.
Post by: gpineau on February 17, 2018, 06:48:02 pm
You can hear the difference on my Facebook post.

https://www.facebook.com/groups/ConcoursOwnersGroup/permalink/10156291418793311/ (https://www.facebook.com/groups/ConcoursOwnersGroup/permalink/10156291418793311/)
Post by: Rubber_Snake on February 17, 2018, 08:13:15 pm
Very nice work!  Sounds great.