Topic: CB350F - What did I find in my oil pan??? ANSWER: starter clutch pin and spring

[HondanutRider]

Its about at 6,000 miles and I figured with the oil change I should pull the pan and check the screen as recommended by the original service schedule.  I obtained this 1974 model the other year and got it cleaned-up and running nice after it had sat idle for 20 years.  I neglected to pull the pan then, as everything else looked so good and I was anxious to get it on the road.  

At any rate, these two items were found lying inside separately.  They appear to go together, but I'm not sure as the pin looks like what the parts manual shows for the oil pump, yet there isn't any mention of a spring.  I haven't pulled the pump yet, so I can't verify if it is missing one of the pins or if there are springs involved.

Anyone help me from the pictures to identify?  Thanks.

[kghost]

Looks like the pin and spring off the starter clutch.

[kghost]

Part number 28126-253-030 and 28125-253-020

http://www.cmsnl.com/honda-cb350ffour-usa_model435/partslist/E++15.html

[Kevin400F]

Absolutely from the starter clutch.  But keep looking, because in order for these two parts to come out of the starter clutch, another piece came out first.  This third part which does not have a Honda part number since it was never intended to come out of the clutch body.  It is a round pin, about 1/3 to 1/2 the length pf the as the hollow "cap", and has a stepped-down diameter to fit inside the spring.

[Bowswell]

Me too, am finding the same thing in the oil pan and  was a cause of the large bolt that had the fillage striper look picture...

[HondanutRider]

Looks like the pin and spring off the starter clutch.

Yes. that's exactly what I thought it might be from the looks of it.  Thanks for linking to the parts diagram for it, as I didn't see that particular page of the fiche.  Looks like there are supposed to be three of these items in the starter clutch.  Since the starter still seems to work OK, I assume/hope maybe its alright to leave alone.

How did it ever end up in the oil pan, do you suppose?  And, how would I get it back in...or should I try?

[MRieck]

 Someone pulled the charging rotor and it dumped out. they must have found the roller. Or maybe they didn't?

[Kevin400F]

There's a plug pin (as mentioned in my post above) that "backs up" the spring and cap you found.  The plug is staked in place in the clutch body from the outside, then the spring and cap are loaded from the inside, along with the roller.  When the retaining plug spits out of the clutch body, going wherever it chooses in the bottom end (hopefully not between gear teeth), the spring and cap fly out and go wherever they want to go also.  The rollers can't get out of the clutch, fortunately.  I found all six pieces in the sump of my 350F (three retainer plugs, three springs, and three caps).  It absolutely amazed me that none of them got crunched.   

[HondanutRider]

There's a plug pin (as mentioned in my post above) that "backs up" the spring and cap you found.  The plug is staked in place in the clutch body from the outside, then the spring and cap are loaded from the inside, along with the roller.  When the retaining plug spits out of the clutch body, going wherever it chooses in the bottom end (hopefully not between gear teeth), the spring and cap fly out and go wherever they want to go also.  The rollers can't get out of the clutch, fortunately.  I found all six pieces in the sump of my 350F (three retainer plugs, three springs, and three caps).  It absolutely amazed me that none of them got crunched.  

It seems the other two units are still in my starter clutch, as the starter seems to work fine.  Should I be worried?  If I was to re-assemble the clutch and re-install these parts, how would I go about doing so?  (Would the case need to be split and the clutch pulled off the primary shaft?)

[Kevin400F]

With the oil pan off, the starter clutch is in plain view.  Since at least one of the three plugs/springs/caps has come out, take a close look at the clutch hub and determine the status of the other two.  It could be you only have one stil in place.  Knowing what I know now about the propensity of these to work loose, I think I would try to re-stake the back-up plugs. 

[Bodi]

 "Someone pulled the charging rotor and it dumped out. they must have found the roller. Or maybe they didn't?"  No, Mike, the 350 has the clutch inside the cases on the primary shaft so unless the "clutch outer" has shattered I don't see those parts getting out. I really don't see the clutch working with only two rollers... I've had too much unlucky experiences with these things to believe that is possible. Maybe an extra spring and cap set was lost in the motor on assembly and has never caused a problem is 30+ years? The pasrts look brand new to me, anyway.

[HondanutRider]

"Someone pulled the charging rotor and it dumped out. they must have found the roller. Or maybe they didn't?"  No, Mike, the 350 has the clutch inside the cases on the primary shaft so unless the "clutch outer" has shattered I don't see those parts getting out. I really don't see the clutch working with only two rollers... I've had too much unlucky experiences with these things to believe that is possible. Maybe an extra spring and cap set was lost in the motor on assembly and has never caused a problem is 30+ years? The pasrts look brand new to me, anyway.

I'll have to have to crawl under and have a look later to see if the clutch case is visible from the bottom.  From the parts blow-up for the 350 Four, it does look like it is visible from the bottom so should be able to rotate it and see the condition.  (i.e. Does it have any staked holes or maybe one that is empty?)  I should also be able to pull the spark plug leads and get the starter to try turning it over and verify that the clutch still works - it certainly seemed fine when I last used it.  (I always used the starter motor and only tried the kick once or twice.)  I've also got to try removing the other three screws holding-in the deflector plate inside the bottom pan, to see if anything else is in/under there.  So far, only one screw has responded to my torque.)

Once I've checked, I'll post another report.

[strynboen]

have find this for 400 f,,think its same pics says more then 1000 vords

[HondanutRider]

Well, I've checked under the motor and believe that indeed you can see the starter clutch mechanism, just beside the gear that the starter idler turns.  From what I can see, there appears to be three holes around its circumference that would correspond to the locations for the three springs and caps that retract the roller clutches.  Two of these holes on mine appear to have a plug in them, while the third seems to be empty.  The pictures included show what I observe.

I'm concluding that the pin and spring I found in my sump belong in this hole.  I haven't found the plug yet, but I am going to strain and check the oil I last drained - maybe its in there or else was "ejected" some time before.  I'm also going to try the starter, as it was previously working and I don't think that the starter clutch was frozen on as it did seem to disengage.  I am also going to clean off the exteriors of those other two plugs with some degreaser and try applying some Locktight sealer to them, so hopefully they can be prevented from coming adrift as well.  That empty hole - perhaps I should try fitting the cap and spring back in and fashioning up a small plug?

[Kevin400F]

The clutch body is "peened" slightly to keep the plugs from ejecting.  The one plug in the photo looks like it may have moved out slightly as compared to the typical original position.  Have you tried pushing it back in, against spring pressure?  If it moves in easily, the peened-over areas will be apparent, and you may want to reach in there with a small steel drift and peen the metal over more substantially.

[wdhewson]

Gentlemen:

Now here is a good helpful competent thread.  I'll be into my C350F engine soon, and will be on the look out for this issue.

A potential solution is to find a friend with a lathe and fashion up a steel plug with about 2 thou taper over the plug's length and 2 thou interference fit.  Clean with light solvent, smear with loctitie, and tap it in place.  A good interference fit will stay put, but it must be done right.

Thanks guys..........Don

[HondanutRider]

Well, I never did find the plug in the oil I drained, so I don't know when these parts came out.  So I've proceeded to fabricate a plug using an old bolt that had an un-threaded shank which was just a bit larger than the diameter of the hole.  Since I don't have a lathe (which would be nice) I shaped it up with a file and my drill press, getting the diameter shaved to be a good interference fit.  I also put a small lip on the end to fit into the spring end.  Guessing at the actual dimensions and shape, the picture shows what it ended-up looking like.

As the tank and battery are off, and its drained of oil, I laid the bike down so I could work on it better.  The plug got tapped in and I staked the edges similar to the other plugs.  Then I applied a drop of extra-strength thread locker to hopefully prevent future "drifting".  While doing that, I also applied the thread locker to the other two plugs, after I tapped the stake marks on them a bit more.  You can almost see the finished result in the last picture.

Hopefully this does the trick.  Thanks to those who correctly identified my parts and especially to Kevin who's description helped me fashion the missing plug.

[Kevin400F]

The finished plug looks exactly right, and your installation method should keep it in place permanently.    Nice work!

 

[wdhewson]

Well done for the plug repair. 

I think that this was one of the best threads on the site.  Helpful, documented with pictures, and very positive. 

More later, Don.

[b1jackson]

I think this will help me a lot.  Similar issue discovered today on a project bike.