Genesis 1100 Gas Flow Oddity


 
E

Ed Chep

New member
In trying to keep my vintage Genesis 1100 functional, it has recently started resisting firing up when the main lighting burner is on the full/start position.
It almost seems like it is blowing out the flame while attempting to fire. Is it possible that too much gas is being delivered.
I discovered that if I turn the burner down, it will light.
The middle burner displays a similar resistance when lighting if the primary burner lit and when it fires there is quite an ignition swoosh noise.

The three ss burner tubes (replaced twice in 36 years) have slight surface rust but the openings are open. The crossover tube between the burner tubes are in similar condition.

The manifold is original and valves have recently been cleaned with carb cleaner and lightly greased with brake grease. It is not apparent if there is wear.

The regulator and hose was replaced with a Weber replacement about a year ago.

The tank is the only new item in the assembly and it is a re-certified used tank which was taken in, inspected and freshened up by a major LP gas supply company.

Any ideas what might cause the grill to not want to light at full throttle?
 
Ed Chep said:
The manifold is original and valves have recently been cleaned with carb cleaner and lightly greased with brake grease. It is not apparent if there is wear.
Click to expand...
That's a head scratcher all right. Did it still light properly immediately after you cleaned the valves. I would probably also try a different tank to eliminate that as a possibility.
 
More often than not it's surface corrosion giving gas flow a very slight change. I'd brush the burner clean and pay particular attention to the little vents or holes right near the igniter. Also a weak spark can be the culprit. Yeah you may "see" a spark but it may not be robust enough to light the gas off. Make sure the igniter system is free of corrosion so sparks are solid and strong and don't do any stray sparks. Trust me do that stuff it'll go back to lighting first click
 
LMichaels said:
More often than not it's surface corrosion giving gas flow a very slight change. I'd brush the burner clean and pay particular attention to the little vents or holes right near the igniter. Also a weak spark can be the culprit. Yeah you may "see" a spark but it may not be robust enough to light the gas off. Make sure the igniter system is free of corrosion so sparks are solid and strong and don't do any stray sparks. Trust me do that stuff it'll go back to lighting first click
Click to expand...
I can clean up the burner tube exterior surfaces a bit more.
I am not using a spark to ignite but rather stick matches.
 
BPratt said:
Probably spider web or nest somewhere in the manifold assembly restricting gas flow.
Click to expand...
I could be wrong but it seemed like excessive flow blowing out the flame.
I can possibly blow the manifold out with compressed air to address that concern
 
Steve Hoch said:
That's a head scratcher all right. Did it still light properly immediately after you cleaned the valves. I would probably also try a different tank to eliminate that as a possibility.
Click to expand...
After cleaning the valves it lit the same as before, not what I'd call properly before or after.
Another odd thing is that once all three burners catch and warm a bit, all can be turned to "Full" and hit 550+ degrees quite quickly.
I had thoughts about the tank. I think they only do a visual inspection to recertify them.
I was balking about getting a brand new tank but maybe that would dispel that thought.
 
Last edited:
Ed Chep said:
I got tired of replacing it. Matches are cheap and there is a hole in the front of the chamber at the start of the primary burner tube.
Click to expand...
Maybe too much gas buildup before you can get the match in there? Are you leaving the lid open during start up? I'm just throwing things out there, not accusing you of doing anything wrong.
 
Steve Hoch said:
The one on my original Genesis 1000 still worked perfectly after 23 years. I just changed it since I was restoring the grill and was changing out all the parts anyway.
Click to expand...
See? There ya go. Two user testimony that they were not trouble prone devices
 
LMichaels said:
More often than not it's surface corrosion giving gas flow a very slight change. I'd brush the burner clean and pay particular attention to the little vents or holes right near the igniter. Also a weak spark can be the culprit. Yeah you may "see" a spark but it may not be robust enough to light the gas off. Make sure the igniter system is free of corrosion so sparks are solid and strong and don't do any stray sparks. Trust me do that stuff it'll go back to lighting first click
Click to expand...
So after another round of going at it here's what I found:

I hit the burner tubes with a circular wire brush in a drill but was realized that rust in not one dimensional. The gas opening slots along the lengths of the burner tubes have some degree of rust in all the exposed edges of the slots and some were narrower than others. I used a welding nozzle reamer to scrape inside most of them so the size that fit the widest openings now fits most of them. That's not to say that any are the original manufactured opening sizes though. The four or five holes perpendicular to the main lines of tube holes are larger round holes and all seem good but a drill bit was used to slightly clean them up.
The crossover tube is another story. It has smaller and recessed openings and is not easy to service. The openings in that are much smaller and although I got my smallest reamer in some of the openings, it is difficult to clean inside. I am not convinced that would matter though with only the primary lighting burner being supplied with gas when lighting. That does bring up an point of interest though in why Weber does not use a crossover in the new Genesis grills but rather has individual igniters.

After that the original assumption remains. I think the gas delivery is overpowering the burners. If I set any or all burner valves to medium they burn well. If I go to high the flames jump off of the face of burner tube as if to be almost blown out but generally drops back and fires off the tube face, then repeat. So too much gas delivery? Or would slightly undersized openings be an issue raising the pressure? I might assume that with all burners open it would tend to reduce the gas pressure though.

As previously mentioned, the regulator at the tank end of the hose is fairly new and Weber brand (so it was presented as such). That's not to say it's not at fault though.

So I'm not sure that I am any closer to the solution. It could be the burner tubes (including crossover), the valves, the regulator or the tank's valving. On the tank I might assume that the hose regulator would control that.

I hate to say if Napoleon 3 burner grill had an open framed base I would go for one but with an enclosed base in the country it's an invitation to mice and squirrels to take up residence in the grill.
 
I thought it was the issue. You indicated you were tired of replacing the igniter. So, have to assume your issue was in there, where as you can see they last an incredibly long time
 
A new set of burner tubes couldn't hurt. You don't even need to buy an OEM set, most of the aftermarket ones work just fine for a lot less money.
 
Maybe some photos or better yet a video of the issue would help a lot. Barring that, I think you should probably invest in a new set of burners as Steve suggests. Your problem could reside in the burner vents that regulate the intake of air with the gas flow. Or it could be an issue with the old burners themselves. Either way, a new set should cover both of those issues. You should be able to get a set for under $20 off Amazon.
 
You must log in or register to reply here.

 

Back
Top