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Discussion Starter · #1 ·
Bike has started, idled and ran real good for about a year and a half now....I've done just about EVERYTHING to rebuild it both mechanically and comsetically EXCEPT for anything to do with the engine itself:



Well I ride it Saturday and it runs great.....I go out Sunday morning to start it and I hear this horrible dull,deep, whirling sound that sounds like it's coming from the back of the engine...it will whirl around for a few seconds then I start hearing some major clunking that AINT good !!! The sound does get faster as you rev the engine....if you put the kill switch to off and just crank the engine you do not hear the noise, you only hear the noise when the bike has totally started and idling.



I know it's difficult to diagnose over the internet without actually hearing the noise but my guess is it's the cam chain...I know I need to drain the oil to see if any metal is in there and that will "help" answer my question. I also know I'm going to have to drop the engine and open it up to tell for sure but the oil might give me a real indicator.



Another issue although it DID run great until now is that I've always smelled gas in my oil...when I'd go to check the oil level I can smell it everytime.....I know my carbs are spot on as the bike RAN great until yesterday...the oil just smelled. I guess my question here is that I've read before where if your carbs are ok and you always smell oil that you have another internal engine issue here ? Is that true and what could internally be causing THAT issue.



I'm trying to determine if this thing is actually worth fixing....let's say the engine isn't all ground up inside due to a cam chain and I get that issue fixed.....do I also have another inner engine issue causing the oil to always smell like gas that I'm going to have to deal with as well ??



My thoughts are that if I need to do more engine work other than a cam chain (to fix the gas smell in the oil) that I'm not gonna do it.



I guess I will drain the oil, drop the engine, open up the back and have a look....it certainly won't hurt anything IF the engine is toast already !!
 

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drop the oil rick,and make a start.you need that rear cover off
 

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Don't part it!!! You can't leave us!!!!!

We don't have another rickbert....
 

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Discussion Starter · #5 ·
I think this video may help you hear some of it....obviously once I started it I didn't want to run it too long, so yes it's short but to the point.



 

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AS its an 82 and from what I can see in your signature pics

its got a vac tap and TI igntion

This suggests its got an auto cam chain tensioner and they have been known to

fail suddenly with no warning.

These are guesses of course but as you've not ridden it or used it much as it is

IF it is the tensioner thats failed, you have a good chance of fixing it

before any major danage has been done.



If you remove the plug on the rh rear cover and have a poke about inside

(small torch and dental miiror may help here)

you may be able to confirm or dismiss this theory

Good luck with it
 

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my opinion is engine out rick.thats nasty,could be a broken cam guide or the like
 

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Just seen/heard the vid

could well be the tensioner or, as Bandit says,

a snapped guide.



Easy enough to fix if caught early

I know guys who kept riding with nasty noises and this is not advised
 

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Rick, not many of the new guys know this but you have had your share of strange gremlins with this bike haven't you! This is the first I have heard about a noise starting suddenly like this.

Before you take anything apart, put a clear drain hose on the carbs, loop it up and open the drain. With the hose held to the engine side of the bowl, let me know where the fuel level is for each carb. If either of them are too high it could be overflowing into the engine and past the rings. There would be nothing else inside the engine that would cause the gas smell. I don't remember if we changed the fuel needles in the carbs after I got them back to wash out the red gas tank coating. There may be some still in one of them that's hanging up the needle when it's sitting if I didn't change them. I would think I did though. But with the vacuum operated petcock it shouldn't be an issue unless that's gone bad and leaking too.

Another way to test that would be to loosen both intake manifolds so they have a gap between them and the head. Let it sit overnight and see if fuel leaks out of the intake manifold while it sits. I use those blue paper towels under drain hoses to see if I have any leaks. They hold the stain well if there is. Put one under each intake to see if you have a leak.

You could also take the fuel line off the petcock to see if that leaks while it's sitting.



As for the engine goes, yes, drain the oil and see what you have. But since it just started you may not have too much show up yet.



One possible reason for the sudden noise is that maybe the starter solenoid may be stuck. It's worth a shot anyway. Pull the starter out and turn the key on to see if it spins without hitting the button. If not, hit the button and see what happens. You'll need to be sure it's grounded though. If it's still spinning it may be the source of the noise. Not likely, but it's worth a shot.



It could be a chain noise but I don't think so. I would suspect something like a magnet coming loose in the flywheel that may be hitting, or a starter clutch screw backing out and hitting. Either way I would be pulling the motor if the starter isn't stuck.



As for your title here, don't be ridiculous! Just look at that bike! Why would you even think of parting it? You know you'll get all the help you need here to get it back in shape. This family doesn't fail each other. And you are definitely part of the family. Actually now that I think of it, except the carbs you are one of the few that's not had any issues with you're bike. Count you're blessings and fix that sweet lady up. She's just asking for some love that's all.



Larry



See, lots of help while I was typing my reply. I don't think the starter could be the problem now after hearing the vid.
 

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Discussion Starter · #11 ·
The petcock works fine, I check it when I change inline fuel filters...I set the tank on a table and test the petcock operation and it works fine, it does not leak when in the on position without any vacuum and it does not drip any gas when in the off position either....when I loosened my carbs earlier this year to put new throttle cables on I did notice some drops of gas in the insulator boots.



However right now I'll bypass this minor gas smell issue then to find out what the sudden engine noise is.......first I'll drain the oil and see if anything is in there. If I don't see anything in the oil then I think Larry is suggesting to take the starter off before I drop the engine ?
 

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A bit of fuel in the manifold isnt unsusual

its what gets sucked in as the motor shuts down and I've seen it lots of times



I very much doubt its the starter motor

Possibly the starter clutch rollers, but my moneys on the cam chain tensioner

or guides
 

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Rick, It's normal to have wet intakes after they are shut off. Don't worry about that. It would be a constant drip that you would be looking for.



Is it just me or did I hear a ringing after the engine was shut off. Almost like someone tapped on a bell or a flat plate of steal. I'm thinking something is hitting the starter ring gear now. Pull the starter and reach inside with your finger to see if the starter gear turns one way and not the other. Also see if you can feel a drag on it while your spinning it. Or a clunk when it goes past a certain point. There may be a starter clutch bolt backed out.
 

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Thats a bummer, Rick. I have no more insight on what the problems is than the already discussed areas. I just wanted to offer my tools for you to drop your engine. And, can I watch too? Seriously, if you need some help or moral support, I am only 60 miles away and will be happy to help where I can. These things can take a week or two to resovle, since you don't really know what parts you need until the engine is opened, then it takes a week or so to get the parts and install them. I have no problem haveing your bike apart in my garage for a couple of weeks if that's what it takes.
 

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I'm thinking cam chain related. Marbles in a can. It's always the worst sound.

A spare engine can be found but this should be easily repaired or at least checked out for the price of a rear cover gasket.
 

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Discussion Starter · #17 ·
Well since I saw no flakes in the oil (which I do understand is no guarantee). I think I have nothing to lose by taking the starter off and doing what Larry suggested, it can't hurt. I'll start there.



Roger if I do end up dropping the engine, I think I have all the tools I'll need to do that. I can at least get it off the bike and take off the rear cover to see inside there and take a pic for you guys. Then once we see what it needs I'll probably bring the engine out to your house to do whatever we see fit after I have the parts.
 

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I have a good engine with a bad cylinder head if you need it. I'll even throw in a good cylinder head. I also have a GL500 engine but it would require alot of cleaning to make it look nice. If your planning on doing a Disney run, you can swing right by.

A
 

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Discussion Starter · #19 ·
Rick, It's normal to have wet intakes after they are shut off. Don't worry about that. It would be a constant drip that you would be looking for.



Is it just me or did I hear a ringing after the engine was shut off. Almost like someone tapped on a bell or a flat plate of steal. I'm thinking something is hitting the starter ring gear now. Pull the starter and reach inside with your finger to see if the starter gear turns one way and not the other. Also see if you can feel a drag on it while your spinning it. Or a clunk when it goes past a certain point. There may be a starter clutch bolt backed out.


Larry,



I took the starter off (that was easy enough) and put my finger in the hole in the engine and felt the gear that the starter turns. It turns freely ONE direction with no hang ups or snags. I do however hear a rattling sound as I'm spinning it around almost like the gear is a little bit loose, don't know if that's normal or not.



Larry, I also did what you suggested after I removed the starter I turned the key on and it did nothing, I pushed the starter button and it spun freely and smoothly and real quiet, I let go of the the starter button and it stops quietly as it should, no odd noises from the starter itself or afterspin when starter button released.
 

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No Rick, that's not normal. It should be smooth and quiet. Sounds like you found the source. When you pull the engine remember that you'll need the large bolt to remove the flywheel. I bought mine at a bike shop years ago. I'm sure you can find one locally instead of ordering it online if you don't have one. The book doesn't say what size it is. It looks like a 20 or 21mm though. If you don't have a compressor and an impact driver you will also need a way to hold the flywheel still while you tighten the removal bolt.
 
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