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:baffled:This is one of the more perplexing situations I have been in. A few days ago I changed the cam belts. I aligned the hash mark and the TDC marks as instructed in the repair manual. The bike was running fine after the belt change. This afternoon I went out to start it and it made a sharp clanging noise, once, and did not start. I made sure the clutch was pulled, the bike was in neutral, and I got nothing out of the start motor. It was drawing current and the headlight dimmed slightly as I pressed the button. Still, no movement from the engine. The charge on the battery was good so I tried to move the engine by hand cranking it. It felt like something inside was keeping it from moving. Could this be a "cam thing?" Help.
 

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longrider wrote:
:baffled:This is one of the more perplexing situations I have been in. A few days ago I changed the cam belts. I aligned the hash mark and the TDC marks as instructed in the repair manual. The bike was running fine after the belt change. This afternoon I went out to start it and it made a sharp clanging noise, once, and did not start. I made sure the clutch was pulled, the bike was in neutral, and I got nothing out of the start motor. It was drawing current and the headlight dimmed slightly as I pressed the button. Still, no movement from the engine. The charge on the battery was good so I tried to move the engine by hand cranking it. It felt like something inside was keeping it from moving. Could this be a "cam thing?" Help.
:waving::waving:Welcome to the Best Goldwing Site on the Internet, longrider!:waving::waving:

I'd pull the timing cover and take a look, it's possible one of the new belts failed or a tensioner got loose and let the valve timing shift enough to let the piston hit a valve.

I wouldn't try to turn the engine over until I'd checked this out. Sorry I can't give you a happierrecommendation. The only good thing about this kind of disaster is that it doesn't always damage the piston and if that's alright it's just a matter of pulling the head and replacing the valve or puttin on a used head.
 

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Hello longrider and welcome to the forum. I'm afraid I agree with Paul, sounds like a belt slipped and a piston and valve are jammed together. Don't even think about hitting the starter button again until you have pulled the covers. You didn't say what model Wing you have, but if its a GL1500 you can pull the covers quickly enough.
If the belt slipped at idle there is a slight chance you migt not have bent a valve, but try not to think about this for now. Just put the belt back on and then turn the engine by hand to check for binding before starting.
 

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I remember a friend who had his belts changed by a mechanic, who after riding for a while had the same problem, it seems the rubber dust seal that should have been glued in wasn't replaced properly and it dropped down and got caught in the belt, this allowed the belt to jump a tooth. we can all guess what happened as a result. Replaced piston, valve and resultant labour costs etc.
It does sound ominous.
 

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Sorry for forgetting a few pertinent details. As you can imagine, I was ready to go riding my 1980 GL1100 on this sunshiny day when the event happened. What is interesting about this is that I never got the engine to even turn over.

So, I need to pull the heads, loosen a few screws so that the valves come back up, then put it back together with the valve covers off, and hand crank it to check for binding.

How will I be able to tell if the belt slipped?
 

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Jason,

If I feel no binding you think it may be o.k. to put it back together?
 

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Jason,

If I feel no binding you think it may be o.k. to put it back together?
 
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Hey longrider :waving: Your very welcome to the forum. :clapper: There seems to be an echo from your last mesg. :stumped: These "Gurus" will soon get you sorted. :jumper:

:weightlifter::18red::weightlifter:
 

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First things first. Take off the timing belt covers and see if the belts are in place, and all the marks line up. That'll tell you a lot first. Then you can proceed to the heads. And you can get to the crank bolt to turn the motor over with a ratchet.

Raymond
 

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Bad news. I followed the steps as you guys outlined. I put even checked for binding. I should have taken off the exhaust pipes and intake manifold pipes and looked at the valves before doing anything else. I didn't.

I pressed the start button and immediately heard a clack, clack, clack noise. I shut it down. I have a feeling I have a broken valve. Did I hear somebody say something about having toreplace thehead if this happens?
 

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longrider wrote:
Bad news. I followed the steps as you guys outlined. I put even checked for binding. I should have taken off the exhaust pipes and intake manifold pipes and looked at the valves before doing anything else. I didn't.

I pressed the start button and immediately heard a clack, clack, clack noise. I shut it down. I have a feeling I have a broken valve. Did I hear somebody say something about having toreplace thehead if this happens?
It does sound like you have the usual results of valve mistiming. The damage can be anywhere from bent or broken valves to piston and cylinder damage. At this point I would pull the head off and take a look. Don't crank it again, each time the damage is getting worse, if a valve head is loose in the cylinder it will be damaging the cylinder walls, possibly requiring a rebore.

If you are lucky the damage will be limited to the valve. Next worse is the valve guide or head is damaged. If it is limited to the head, I'd start looking at eBay or one of the bike salvage outfits for a used head.
 

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Of no use at all but....................

A couple of years ago I'd just bought a GL1000. It was a sunny day and an excellent excuse to use a bike. :clapper:

On pushing the starter it made a very terminal sound (the sort that makes you look for protruding con rods etc) and noting would move afterwards. :stumped:

Being fortunate in also having a old Triumph, I jumped on that. The night before, I had started it with no problems. This morning it showed all the signs of having a flat battery. :stumped:

So I got in the car and off I went.:whip:

The problems with the bikes bugged me all day. Coming back along my favourite bit of twisty road I found a load of oil and water mid way round a bend. A bit further I found two cars that had come to grief. With four wheels and ABS it was no problem but I was forced to wonder how I would have coped on either bike. :baffled:

After dinner I went out to find out what was wrong with the bikes.

The Triumph's battery was fine even though I'd not charged it and it started first time. :gunhead:

Having checked all the obvious things with the 1000 I dabbed the starter button and she also started with no problems. :gunhead:

Anyone believe in guardian angels? :D
 

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Good news-I hope. I pulled the heads and noticed that none of the valves were broken. I wonder if one of the valves got bent when hit by the piston. Number one piston has, what looks like, fresh scarring on the lower half of its face. I'm thinking the number one exhaust valve must have come into contact with it. I'm also thinking thatthe valve is probably bent and sticks.

I suppose I'm looking at replacing the valves in that head for sure. Any other recommendations?
 

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The valve is probably bent, and you need to do a real check out of the whole valve train, rocker arm, lifter, etc. When that valve hit the piston it was the same as you taking a big hammer and hitting the valve head on one side. So everything in the head that's part of the valve train was REALLY overstressed. Personally I'd start looking in eBay or a salvage yard for a decent used head. Normally if an accident like yours doesn't happen, these things last near forever. Simply replacing the head might actually be cheaper than buying new parts. It's basically just replacing the head and gasket and resettingthe rocker arm shims.
 

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So...... Did you ever pull the timing covers off first to see if your cam pulleys were out of time with the crank pulley? Obviously it's all off now..

Raymond
 

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Yes I did. Of course, with the engine not moving, there wasn't a whole lot I could do. After the engine stoppage, I expected the timing marks to be anwhere but aligned. And I wasn't surprised that they weren't on the time marks.

How many times does the timing mark, TDC, in the engine have to go around before the marks should line up again? Ideally, if I get the marks lined up exactly, then after (four??) rotations they should line up again-right? Is it possible that they wouldn't?

If they didn't, what would be next in my list of things to look at and replace?
 

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I believe 2 revolutions of the CRANKSHAFT will bring the cams back to where they belong for the timing marks to lineup IF they were aligned to start with.

Pat
 

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Longrider,

Look at the crank pulley compared to the cam pulley. The cam pulley is twice the diameter of the crank one so it's a 2 to 1 ratio, two turns of the crank to one turn of the cam. This is the set up on almost all four stroke engines since each cylinder fires every other turn of the crank.

Inspect your cylinder walls to make sure there are no scratches. If the piston isn't chipped but just has a shallow dent from the valve it probably is okay. The thing to do now is to do a careful inspection of the valve guides, lifters and cam and rockers. When the valve hit the piston it put some severe stresses on the whole valve train and all the moving parts in the head are suspect now. It's important that you check all that out carefully. If there is damage in the valve train and you put it back in operation you are likely to have another catastrophe soon.

If it were my bike I would really look around to see if I could buy a used head. They come up reasonably often on eBay and there are several bike salvage yards that you can find with a Google search. They aren't all that expensive, you probably can get another head with valves for less than the valves would cost you new. You will need a new head gasket and will have to readjust the valve shims.
 

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Well, if you had one mark right on, and the other was way off, you had a belt slip a few teeth. Obviously too many. You said you had just changed the belts, so try and figure out what went wrong, so you don't repeat it.

Sice you have the heads off, I would take the head that had the valve hit the piston, to an expert and have them inspect and possible lap the valve. Make 100% sure the valve is seating before you put it all back together.

And figure out what went wrong. Were the belt(s) real loose? Sounds like maybe an adjuster came loose, or it wasn't tight enought to begin with.

Raymond
 

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Erring on the side of caution, I went to the bone yard and got another head. Got new gaskets too. The new head came off of a bike that supposedly had fewer miles on it than mine. I put it on with new gaskets, adjusted the rockers, and put the belts back on. I put the belts back on making sure all screws were tightened, belts tight, and the tensioners were not not too loose or overtightened-just like it says in the Clymer repair manual. I pressed the start button and it cranked right up.

Oh yeah, there's no hesitation or skippingfrom the engine. However, I'll ride it to close destinations, with a variety of highway and city driving to test it. I'm even thinkig about pulling the timing belt cover off periodically and checking the alignment marks again just to be safe. Am I being a little too cautious here?

p.s. the crank pulley and the cam pulleys are turning just like you said they should 2:1. Yes, I cranked by hand numerous times just to see if I could detect binding or a sticky valve or anything tht might suggest interference with the timing. I even changed the gaskets on the tming belt cover just make sure it didn't have any pieces coming off and interfering with the belts.
 
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