Gs850 issues

[Scudder]

Got the gs850L started and running. Cylinder #2 isnot firing, but I haven't had time to look into the carbs. It's got spark, etc. The thing starts fine, except for once issue that scares me abit.

The other day, after it had set for a while, when I went to start it, it turned over fine and then WHACK! A very loud, singular WHACK! THen it died and wouldn't turn over immediately following. Sounds bad. But... then in a couple minutes it starts right up and sounds great.

This WHACK, has happened twice. I'm not starting it again until I take off the cam cover and take a look at the cams, chain, etc.

What's crazy is it idles fine and seemingly is running well. I have no idea what it could be or where to start with this problem. Thanks for the help.

Scudder

[BassCliff]

Hi,

Hydrolock on #2?



Thank you for your indulgence,

BassCliff

[Scudder]

Pardon for my misunderstanding, but what is a hydrolock. Sounds bad. Is in the valve or cylinder? How do I fix it?

Scudder

[Big T]

Petcock leaking fuel into the cylinder, filling it up. Liquid is noncompressable, so engine won't turn over. Clue is that #2 is not firing because it is flooded

More likely, the WHACK is your starter clutch, pull off the stator cover and check

[tom203]

Disconnect petcock vacuum line and plug at carb end- this will prevent fuel is leaking down to #2 carb; it might have only leaked when vacuum was applied (mine did this). Check that no fuel flows in "on" or "res" position and nothing dribbles out the open vac port on petcock. Check oil level and give it a good smell- any sign of gas? If not, trying running on "prime" and see if #2 cyl starts behaving.

[Scudder]

Ok. I just installed a new petcock after por-15 in the tank. Gas has been leaking. As a matter of fact, when I got home from work last night, I had a pool of gas in my garage. Not good. So... of course I tried to start it and that was the second WHACK.

So am I to pull of the starter cover, or stator cover and check? What will I see to verify that the gas is flooding cylinder #2?

The petcock that I bought doesn't have a adjustment handle. Only a slot for a small screw driver. I didn't have it on prime. The tank, immediately after I treated it leaked somethin' awful at the petcock. I pull rubber washers on the screws that bolt the petcock to the tank and the leaking stopped. Thought I'd solved the probem, and then WHACK! Leaking gas and more issues.

Thanks
Scudder

[Steve]

The petcock that I bought doesn't have a adjustment handle. Only a slot for a small screw driver.

Unfortunately, that is the correct one.

One position (I don't remember which one) is RUN, turned the other way is PRIme. You have no REServe position.

.

[Scudder]

The old petcock I took off the bike was exactly like the one that I purchased and installed. I've heard on this forum that this is the kind of petcock the 1980 gs850L has, however that being said, obviously something is wrong.

scudder

[Big T]

So am I to pull of the starter cover, or stator cover and check? What will I see to verify that the gas is flooding cylinder #2?

Thanks
Scudder

Pull the #2 spark plug and crank the engine by hand. See if the plug is wet with gas and if anything comes out of the plug hole when you turn it over

The starter clutch issue won't tell you anything about the problem with #2. Pull the stator cover and see if the big gear is loose.

[Dogma]

Unfortunately, that is the correct one.

One position (I don't remember which one) is RUN, turned the other way is PRIme. You have no REServe position.

.

I have one, and I can't remember which is which. Sorta hard to remember when you only use it once a year.

Well, I checked. Horizontal is run, vertical is prime.

The only way a new (and not defective or clogged) petcock should flood #2 cylinder is if it was left on prime after running (a vacuum pulse is required to start flow, even on prime).

[Scudder]

I pulled plug 2. It didn't smell of gas. Pulled the other plugs to compare. They were normal dark, maybe a bit rich. However, based upon what I know, 1,3&4 looked and smelled normal. 2 was like a new plug. Took off the stator cover. As I was gingerly pulling it off a large washer fell off and I notice the large gear was loosely engaged. I went ahead and took it all the way off because it was basically hanging there. Now... I have two washers and don't know where to place them on the large gear. How could the large gear get loose like that? Seems kind of unusual to me.

Could this disengaged gear cause my #2 cylinder problems. If so, how and what do I do to get going in the right direction.

While I was at it, I removed the cam cover and turned the engine by hand. The valves seem to be moving fine and everything looked normal. I still need to adjust the valves though.

Thanks,
Scudder

[Big T]

The starter clutch being loose is a common issue. It's likely not related to the #2 cylinder issues. Fix it and the WHACK will be gone

The 2 large washers probably go on each side of the idler gear, check your parts fiche

You do have service manual for the bike?

OKay, back to the #2 problem = getting fuel?, getting spark?, compression - I see you need to adjust the valves - start there

You say #2 plug looks new -probably not getting fuel

[Scudder]

I have a manual. I'll adjust the valves over the weekend. Hopefully that will take care of it.

Scudder

[Scudder]

Adjusting the valves will help the compression which will inturn help get the gas from the carb to the plug which will let cylinder 2 fire? Am I on the right line of thinking?

Scudder

[850 Combat]

Adjusting the valves will help the compression which will inturn help get the gas from the carb to the plug which will let cylinder 2 fire? Am I on the right line of thinking?

Scudder

Probably not, but you need to do it anyway. If it doesn't run on on any or all cylinders it will still be a fuel or spark thing nearly every time. It would take a mechanical problem of very large magnatude to make it not run at all on a cylinder.

If you crank it with the #2 plug out and there is a big air escapement noise from the plug hole, there is proabably enough compression for it to run.

Have you traded the #2 and #3 plug leads and plugs around? If that doesn't help, I would get into the carbs again.