[jonzo454]

VN900, only about 4000 miles, obviously pampered life, always garaged. Suddenly won't start. Battery was weak so I replaced it. Still just cranks and cranks. Removed filter and sprayed starting fluid in intake, no change.
Short time before complete no start it was hard starting and backfired a bit before straightening out and running decently.
Any thoughts?

 

[sfair]

Remove and post a picture of the plugs.

Do not use starting fluid.

 

[jonzo454]

It is below freezing currently. I will post the picture as soon as it warms up a little.
What damage will starting fluid do? I have used it to troubleshoot fuel injected cars before.

 

[sfair]

What did you learn by using it?

 

[jonzo454]

The vehicle had a bad fuel pump.

 

[sfair]

No, I mean on your motorcycle.

 

[jonzo454]

Oh. No change. Still no attempt to fire.

 

[sfair]

Oh. No change. Still no attempt to fire.

That is why I do not recommend ether. It does not advance your knowledge base and there is always a risk of backfire and subsequent inferno. If the engine should start, one usually gets a brutal knock because of the uncontrolled burn of ether.

Have you checked for spark? Be careful that if you do that, you get no ether exhausted onto the plug and an ignition.
While the plugs are out, post a picture of them.

 

[jonzo454]

I pulled the rear plug. It's really gas-soaked. I am ordering 2 new plugs.

 

[jonzo454]

I changed the plugs for fresh replacements. It now starts and runs. I ordered a K&N air filter too.

 

[Hot Cruiser]

I pulled the rear plug. It's really gas-soaked. I am ordering 2 new plugs.

From the photo it appears that the spark plug is oil-contaminated, and especially at your reported 4000 miles the plugs should be much cleaner. When I changed mine on my 900 at 9500 miles they looked as new, with no deposits or contamination. Is the engine oil level in your bike too high? It appears that quite a lot of oil is getting into your engine.

 

[jonzo454]

From the photo it appears that the spark plug is oil-contaminated, and especially at your reported 4000 miles the plugs should be much cleaner. When I changed mine on my 900 at 9500 miles they looked as new, with no deposits or contamination. Is the engine oil level in your bike too high? It appears that quite a lot of oil is getting into your engine.

They smelled like gas. And there was no smoke from the exhaust when it was running. I don't think the oil is overfull but I'll probably change it soon anyway.

 

[sfair]

That plug is carbon fouled.
The problem that caused them to foul in the first place may still be present.
Run them for a bit and then recheck again for carbon deposits.

 

[Wild Bill]

I suggest you check your plugs after a little riding. Maybe she is running too rich and causing foaling.

WB

 

[FerricOxide63]

I changed the plugs for fresh replacements. It now starts and runs. I ordered a K&N air filter too.

Cool, I like a happy ending! 👍

Sent from my SM-G900W8 using Tapatalk

 

[Bandit]

Now to find out why the plugs fouled so bad in the first place.

 

[Hot Cruiser]

They smelled like gas. And there was no smoke from the exhaust when it was running. I don't think the oil is overfull but I'll probably change it soon anyway.

There has to be a reason for that spark plug to be so badly fouled and that problem needs to be sorted out or it is likely that the same no-start situation will recur. Also there probably will be carbon build-up on the valve faces and interior cylinder head which will get worse and will result in more difficulties, among them pre-ignition. It would appear that oil or possibly excessive gasoline is getting into the combustion chambers and being burned, resulting in the carbon fouling situation. Whatever the cause it needs to be detected and resolved. Suggest following sfair's recommendation.

 

[durox]

Hi,
I would like to see some more pics of the spark plugs. It's easy to misread one single picture.

Spark plugs can get dirty if they don't reach the operating temperature... Combine that with a rich idle and one could end up with something like that over the cold season.
I don't think that's an oil deposit but gasoline (carbon) fouling.

*don't idle the engine if you're not going to ride -as a maintenance over the winter.

 

[jonzo454]

I already discarded the plugs. But I believe they were gas-fouled. The plugs smelled like gas when I removed them. Of course, by this point they probably couldn't fire because they were so fouled. The air filter was dirtier than I would have expected at this point so I ordered a K&N filter. And although I don't start it and idle it ever, much of my recent riding has been very short trips where the bike probably didn't get really warm. In the future I will pull the plugs occasionally and inspect them.