Weird Noise

[burly]

My 1999 Nomad has started making a strange metallic rattling sound (not real loud, but you can hear it over the motor) that begins a few minutes after ignition, and gets more constant until about 5-10 minutes have gone by and the motor warms up. Then it stops. Sounds like it's coming from the top end, but I can't localize it. I thought at first it was the pipes - I had some loose chrome happening, but I replaced and tightened everything, and it's still there.

It's not related to throttle or clutch.

Any ideas what this might be before I call in the mechanic? I am mechanically challenged so speak slowly :-)

[ringadingh]

Check to see if its anything external, like the rad screen, header pipe heat sheild etc. It could also be your cam chain rubbing on the spark plug tube, unscrew the tubes and check for wear marks, if the chain does cut through the tube, you will notice an oil leak. Although some of these noises wouldn't go away after a few minutes like you mentioned.
Sometimes it takes a while to pinpoint, you have to start checking everything and eliminating stuff.

[MAS Tequila]

KACR

Drain half the oil out of the bike and replace with ATF (transmission fluid, not the government agency) and run 20-30 miles.

Change the oil and use a high quality synthetic. This 'should' take care of most rattles that aren't mechanical in nature.

MT

[AlabamaNomadRider]

Sounds like it isn't getting enough lubrication. Then it finally warms up and everything gets back to normal. Could be that the oil isn't getting pumped properly.

[burly]

Originally Posted by AlabamaNomadRider

Sounds like it isn't getting enough lubrication. Then it finally warms up and everything gets back to normal. Could be that the oil isn't getting pumped properly.

That may be the problem - I had replaced the POG with Judge's JOG, but the JOG failed. I replaced it, but maybe the pump was damaged in the process.

[burly]

Originally Posted by burly

[quote author=genecross board=nomad thread=19189 post=289885 time=1281714186]Sounds like it isn't getting enough lubrication. Then it finally warms up and everything gets back to normal. Could be that the oil isn't getting pumped properly.

Very good call, Gene! I checked my oil level over lunch today, and it was down significantly. Added oil, and the noise seems to be gone. Now I have to figure out why the oil is down...I just put Rotella T6 in and had 1100 miles on it. Is it normal to use oil after adding synthetic to an older bike? There are no visible leaks.

[ringadingh]

It doesn't have to leak oil to lose it. It can be bypassing the rings and go out the tailpipe. It can happen so you have no sign of it happening, unless you check your oil level.
My bike will easily use a litre between oil changes, especially at highway speeds of about 75mph.
I was going to suggest checking the oil but I assumed that would be one of the first things you already checked.
Keep your eye on it from now on, and it should be fine.

[burly]

Originally Posted by Ringadingh

It doesn't have to leak oil to lose it. It can be bypassing the rings and go out the tailpipe. It can happen so you have no sign of it happening, unless you check your oil level.
My bike will easily use a litre between oil changes, especially at highway speeds of about 75mph.
I was going to suggest checking the oil but I assumed that would be one of the first things you already checked.
Keep your eye on it from now on, and it should be fine.

Thanks Ringadingh...and now you know never to assume anything with me. Next time I'll check first.

[ndbigfish]

Brent,
What happened to your oil gear? How long did the JOG last? What was the cause of the failure? Did you put a stock gear back in? My 99 has oil pump gear problem now, but prior to this it has never burned, by-passed or leaked oil. I never had to add oil between oil changes.

[burly]

Bad news - the noise continues unchanged, even with oil added.

It sounds like something rotating meeting resistance, and I think it's from around where the oil gear shaft is on the right hand side of the bike (as you sit on it). I'm afraid that this means the pump is going. Still wonder why it goes away when it warms up, though...

Ndbigfish - my initial JOG lasted 1 year. I think it failed due to an accident I had in Custer at the National Rally last year. All the teeth sheered off. Judge replaced it, and I've had the new one in since last summer.

The oil consumption is new since I added Rotella T6 synthetic last change. Using Dino, I used nothing between changes. I'm wondering if the consumption has something to do with the pump problem.

Anyway, I think that' s it for this Nomad. If replacing the pump means splitting the transmission as I suspect, I can't afford to put anything more into a 1999 bike. The thing has been a stream of problems since I bought it.

Off to the mechanic for an official verdict. Thanks for all the suggestions, everyone.

[MAS Tequila]

Stick a 1600 in that 99. I know of many 1500s that are now powered by newer 1600s.

Mine is one. It's an easy swap. Just find one you can pick up for a song. Once it gets cold you can get a fairly low mileage one for around a grand.

That's a lot cheaper than another bike.

MT

[ndbigfish]

Dragonchaser,
It there a place (thread) that has a break down of the things that are required to make a conversion to a 1600?

[MAS Tequila]

Originally Posted by ndbigfish

Dragonchaser,
It there a place (thread) that has a break down of the things that are required to make a conversion to a 1600?

It is a direct bolt in. They use the same mounting, intake, wiring,exhaust, ...et al.

If your bike is carbed you will have to drill and tap one hole in each head for the lower mounting bolt. If it's an FI bike then it's identical.

I used all the connections from my 1500 and it went in with no problems.

If I can do it, you can do it.

MT

[burly]

Sorry for my previous rant. One thing after another gets to you after awhile...and the suggestion to replace the motor and transmission at 20,000 miles put me over the deep end. I feel better today :-)

If I could get back to my original problem, I think it's the water pump. It makes a sort of metallic, chirping sound very intermittently which goes away once it warms up.

If it's bearings or something deeper I'm once again in the dreaded "remove the engine, split the crankcase" zone. I don't do my own wrenching, so that's the equivalent for me of "take the motorcycle, lift firmly and place in the nearest garbage can".

Any bright ideas from all you very wise and patient Nomadians on stuff to try before I call in the mechanic?

[macmac]

burly, I think the previous owner is more to blame than kawii is.

Perhaps to confirm the noise you would use a long metalic rod if you have one. I use techs stethescopes and or long extentions. You can pin point many noises that way.