Why does my VLH die out?

[Jim]

Why does my VLH die out? During an idle it idles fine. When I give it any gas, it dies and wants to quit, AND you can "hear" the air going in the carb, but no "engine RPM response". If I keep working the throttle it will finally REV up, but not long enough to "drive away". Sometimes it will pop and "Chuff" through the carb too, but not consistently. (For now, I have air cleaner removed)

I have been fooling with this bike for at least a month fixing little things to get it running again. Just for an idea of things I did, I replaced the coil, I replaced float in carb due to it being broken and also cleaned the carb. I cleaned out old gas tank sealer (I don't recommend using this stuff). I set the points/ignition to fire exactly as the Riders Manual says. The other day it ran just OK (sort of) but I felt that the carb still needed some adjustment. Today I removed the carb AGAIN to make sure no "gunk" got into it from the gas tank because the gas filter was a mess (Yes, I had cleaned it before). Carb seemed clean and fine... BUT... now it won't run right. When I pulled off the carb the carb gasket kind of separated and some stayed on the manifold and the main part of the gasket came off OK. The bike will start and idle, but when I throttle it up, it dies... you can hear the throttle "air sound" when working the throttle grip back and forth. But, if I try to pull away, I cannot give it enough gas to "GO"... it just wants to die out. Right now I have the low/idle setting turned out about 3 turns, and I moved it in and out with no difference. Sometimes while idling it will 'rev' up and down.

Could this all be just a carb gasket problem? Do you think that some more "JUNK" got up into that main nozzle venturi? I blew it out really good with compressed air.

FYI... this is a Linkert M344 and yes, I know it's for an Indian... HAHA! But it always used to run really good!

I don't think the float level would make it pop through carb. I am out of ideas and getting tired of "guessing".

[exeric]

I am no mechanic but I have had fuel line problems, and gas caps that were not venting properly and both of those issues had similar symptoms to your's. . . . We have now reached the end of my diagnostic skills.

[Jim]

I am no mechanic but I have had fuel line problems, and gas caps that were not venting properly and both of those issues had similar symptoms to your's. . . . We have now reached the end of my diagnostic skills.

Thanks, I will give the gas cap a check tomorrow. I know it has vent holes, but; they could be clogged. I am "done" with it today.

[T. Cotten]

Jim!

I always place my bets on a vacuum leak.

Here's an absolute test: http://virtualindian.org.11techleaktest.html

Good luck!

....Cotten

[harleytoprock]

Does it run better with the choke in almost closed position? If so, its a fuel starvation problem or like Cotten said vacume leak. Easy way to check the gas cap for venting is just run it with out the cap. Its is also possible that it is a ignition problem. Have you changed the plugs? A gas fouled plug can behave like that. With the carb high speed needle out 2 full turns and the slow needle out 5 turns it should be running plenty rich. The main nozzles in the carb is vented. These old carbs are vented in different ways. I'm not sure of the method on your carb. I worked on a bike that would not move. I discovered that the air cleaner backing plate was covering the carb vent hole. I had to drill a hole in the air cleaner back plate and it was the fix.

[Jim]

Jim!

I always place my bets on a vacuum leak.

Here's an absolute test: http://virtualindian.org.11techleaktest.html


Good luck!

....Cotten

Cotten, Thanks, I found it. That is a easy way to test your manifold! The URL that you gave is supposed to have a "slash" rather than a '.' after the org. Like this: http://virtualindian.org/11techleaktest.html

[Jim]

Does it run better with the choke in almost closed position? If so, its a fuel starvation problem or like Cotten said vacume leak. Easy way to check the gas cap for venting is just run it with out the cap. Its is also possible that it is a ignition problem. Have you changed the plugs? A gas fouled plug can behave like that. With the carb high speed needle out 2 full turns and the slow needle out 5 turns it should be running plenty rich. The main nozzles in the carb is vented. These old carbs are vented in different ways. I'm not sure of the method on your carb. I worked on a bike that would not move. I discovered that the air cleaner backing plate was covering the carb vent hole. I had to drill a hole in the air cleaner back plate and it was the fix.

The Choke made no difference in how it ran other than it would not idle as good as I started to close it. In other words... it didn't help. I thought too that it may be 'starving' for gas. I DID go out and blow through the gas cap and the vent is Clean and free of dirt or rust.

My Plugs? Well, they aren't new and I DID clean them this afternoon but haven't run it since I cleaned them. I also double checked the gap too.

I also have the air cleaner plate OFF the bike now while I am getting it going. I doubt that the air cleaner I have is blocking any holes because the bike ran fine with it on a couple years ago when I was running it. I am betting it is the Carb/manifold Gasket... the one that mounts the carb to the manifold. Looks like these:

https://aaok.com/media/catalog/produ...5/8/5817_1.jpg

[T. Cotten]

Thanks Jim!

By the time I noticed miss-link, the forum format would not allow me to edit!

....Cotten

[exeric]

I have one other suggestion, but it may be way off. Condensers can exhibit some strange symtoms, and they are of notoriously poor quality in these modern times.

[Jim]

I am more sure now it is the intake gasket is the problem. I pulled the carb off this AM and found that a BIG chuck near the top hole is missing. That missing area is less than half the thickness of the "good" areas. Probably fell off when I took the carb off a week ago (or thereabouts). I ordered a couple of new ones today... Should have it Monday.

[Peter Cooke]

While your waiting for your new gaskets use your old one as a pattern and cut one out of a piece of thin cardboard like a breakfast cereal box. That way you can test your theory and keep looking if it doesn't fix it.

[T. Cotten]

Jim!

This narrow gap between bolt hole and spigot hole is painfully tiny.
I am not certain whether a fat or thin gasket is best, but we all must agree that the two mateing surfaces must be proper.
Particularly since this interface cannot be pressurized in a practical manner, yet.

The manifold can be ground flat on emery paper, or better yet, the side of a large grinding stone. The spigot of the carb flange demands however, that it be cut to flat upon a lathe, or whatever (Attached).

The last area to clean up is most often at the gallery plug.

....Cotten

[Jim]

Jim!

This narrow gap between bolt hole and spigot hole is painfully tiny.
I am not certain whether a fat or thin gasket is best, but we all must agree that the two mateing surfaces must be proper.
Particularly since this interface cannot be pressurized in a practical manner, yet.

The manifold can be ground flat on emery paper, or better yet, the side of a large grinding stone. The spigot of the carb flange demands however, that it be cut to flat upon a lathe, or whatever (Attached).

The last area to clean up is most often at the gallery plug.

....Cotten

Hi Cotten, Actually, I was referring to the area "next" to the top hole, not just underneath it although that is a tiny 'missing' spot too. The area that looks like it has a crosshatch pattern. In other words, IF the top hole is 12 o'clock, then look at the 11 o'clock position. ;^)

While your waiting for your new gaskets use your old one as a pattern and cut one out of a piece of thin cardboard like a breakfast cereal box. That way you can test your theory and keep looking if it doesn't fix it.

Anyway... I did what Peter suggested in making my own "temporary" gasket out of cardboard. This cardboard is thicker than a cereal box, but not as thick as the "Linkert" gasket. The bike started and I found that it is running pretty good now. But, I have to run with the choke on the "FIRST" click. If I open the choke fully, it kind of 'bogs' a tad from a fast twist of the throttle. I close the choke one notch and it runs as it should. I wonder if putting the air cleaner on would change anything... Then again, it really isn't an air cleaner, but more of a metal snorkel if you're familiar with those. IF not, then I suppose that is just a matter of adjusting the carb screws now? But, I won't do that until I get the new Gasket on. More on that later...

[T. Cotten]

Jim!

I know it is enormous fun for many of us to tinker and play with these things.
Much of my youth disappeared in just that manner.

But at the risk of losing play time, you might just as well cut your other losses by securing all loose ends before you overheat something.
If something isn't right now, more things won't be soon.

Its sucking air.

Don't feel all alone..

...Cotten

[Jim]

Thanks Cotten, I have pushed it back into the garage corner until the new gasket arrives. I have to learn to "leave it alone".... HAHA!