'87 GN250 with engine clicking & ticking?

**h0dgep0dge** · 21st November 2014, 12:11

I recently bought an older nth hand Suzuki GN250, and at time of purchase everything seemed fine. The first thing I noticed was the noise coming from the engine. A strange clicking, tapping, or ticking noise. After some research I'd learned that this could be valve noise, requiring a valve clearance adjustment. Fast forward about a week I'd gotten the valve clearance adjusted properly according to the manual, with a proper tappet adjustment tool, feeler gauge, and all. No joy. Since then the noise has been getting gradually worse, and it really has me worried. My question is where should I look next for the problem? Is this even worth worrying about, should I just ignore it?

If you care to have a listen, I've uploaded some recordings here: http://h0dgep0dge.github.io/gn250.html
One is the raw recording and the other is the same recording, with a 2KHz high-pass filter.
Throughout the recording I rev the engine from around 1250 up to 4000 and move the microphone close to and far away from the engine. Listen all the way through to get all the information.

Cheers.

EDIT: So apparently there is no way to edit the title. It's just a typo, ignore it

**buggerit** · 21st November 2014, 12:30

Billy Goat Gruff?

**h0dgep0dge** · 21st November 2014, 12:35

Originally Posted by buggerit

Billy Goat Gruff?

What are you referencing?

**buggerit** · 21st November 2014, 12:47

Originally Posted by h0dgep0dge

What are you referencing?

Hunting And Fishings new cookbook, "Catching,cleaning and cooking Trolls and other small game"

**Murray** · 21st November 2014, 12:48

I wouldnt ignore it!!!

Is it using oil???

**ducatilover** · 21st November 2014, 12:52

Has it even got oil?
If I remember to PM you when I'm back in Hatsings I can have a look at it for ya, I think I might still have a few GN parts floating around

**h0dgep0dge** · 21st November 2014, 12:57

Originally Posted by Murray

I wouldnt ignore it!!!

Is it using oil???

I don't know if it's using it up, but the level is fine as of right now, perhaps 2 or 3 mm below full.

**Murray** · 21st November 2014, 13:25

similar noise to what I had in wifes GB400 and it was a broken cam chain guide. Doesnt sound like valves. As said above it almost sounds like it has no oil in the engine??

sorry cant help much but hopefully someone can

**h0dgep0dge** · 21st November 2014, 16:33

Originally Posted by Murray

As said above it almost sounds like it has no oil in the engine??

There's certainly oil in the engine, though is it possible that it's not being circulated properly?

**Pumba** · 21st November 2014, 17:26

Man I dont remember my old GN sounding so tractor like. Never did record it though. If you have adjusted the valve clearance my next suggestion would be checking the cam chain and chain guides.

**h0dgep0dge** · 21st November 2014, 20:11

Originally Posted by Pumba

Man I dont remember my old GN sounding so tractor like. Never did record it though. If you have adjusted the valve clearance my next suggestion would be checking the cam chain and chain guides.

That's what the manual suggests. I'm currently in the middle of a move, and I don't know yet how involved the procedure is, so I may have to wait a few days before I can take a look. I'll report back when I do.

**ducatilover** · 21st November 2014, 22:10

GNs do wear the cam journals quite often, and they shit guides, tensioners and chains. I probably have guides, tensioners and chains, doubt I have a head though

**h0dgep0dge** · 29th December 2014, 13:30

I've just gotten around to taking a look, and so far I've got the cylinder head cover off. If anyone has any advice on exactly where to go from here, that'd be great. I've only had a look at the faces on the rocker arms, but I'm not sure what I should be looking for there. They look like they might be worn, but it could also be regular grinding marks. They're slightly convex, that's really all I notice. I can post pictures if anyone wants to see anything.