won't run

[larry emrick]

After faithfully getting me through the worst of this dreadful weather (two full weeks in 4x) my '74 weber carb gasoline 88 suddenly packed it in yesterday. It will start and idle perfectly on full choke but as soon as I either start pushing in the choke or giving it gas it cuts outs and backfires; pull the choke full on and it returns to a normal idle. It's got lots of fuel in the tank, I have given it some gas line antifreeze and nothing appears to be disconnected. Interestingly, even warmed up, it idles perfectly on full choke without blowing any black smoke, which it normally does if I leave it on full choke too long. It will also move under its own power on full choke idle but as soon as I touch the gas pedal it cuts out. Any help would be appreciated. Thanks, Larry.

[exmod110]

Sounds like a good sized vacuum leak, check for any lines off, or cracked or even a loose carb???? do you have power brakes? or any other vacuum uses? could also be the timing has gone way out too..

[DaveB]

Might also want to check for ice crystals in the float bowl that slipped through before you added methyl hydrate. If the water was in the lines before freeze-up it would make its way through the filter and could have frozen in the float bowl. I had similar symptoms on my tractor that I plow the driveway with recently and that's what it was.

cheers, Dave

[ANDYD]

Hi Larry,

I remember having some what similar problems with a blocked breather hose on the gas fill.
Do you have the gas cap with the little piece of gauze on the inside of the gas cap? Check it is clean and clear.
One way to confirm, is run the engine without the gas cap for a few minutes to see if it helps the situation.

good luck,
Andy

[larry emrick]

Gentlemen: I still have not sorted this out, despite three bottles of gas line antifreeze , draining the filter housing again and trying out the no gas cap idea. I was hoping not to have to drain the tank with $30 of gas in it but that would appear to be tomorrow's project. Is there anything particulalry difficult about doing so? I have the 3/4 inch socket ready to go so long as the plug is not frozen or rusted in. Would I be correct in thinking that if there is water in the gas then it will be in the bottom of the tank , which should enable me to save some of of the gast, any suggestions are appreciated. Thanks, Larry/

[rezdiver]

I am not sure if draining the gas tank is a necessary solution. have you gone through all the other possible issues in the previous posts. if she runs on full choke, i dont think that your tank is contaminated.
i second the vacuum leak or lose manifold or carb needing a cleaning.

[Rob]

I would suggest draining the tank will be a dirty and potentially dangerous job and I recommend you avoid doing it if possible. That being said, you could eliminate the tank as a problem by disconnecting the feedline from the tank to the fuel pump (at the fuel pump) the connecting a jug if fresh gas to the fuel pump with a hose - if the motor runs much better it would indicate looking for a problem somewhere in the tank or fuel line. I fhtere isn't much change then supply from the tank doesn't seem to be the root of the problem.

Some things to think about:

Does the truck still have the mechanical fuel pump and sediment bowl? If so, be sure to clean the sediment bowl (I would look for signs of water there)

Gas line antifreeze doesn't do a good job of melting existing ice so if there is a lot of ice in the carb it will need to be warmed-up so the ice can melt (and the alcohol in the antifreeze can then bond to the water and allow it to get pushed through the carb and motor). You may want to consider parking in a heated garage (or at least warming the motor compartment if you figure the fuel tank and fuel lines are not frozen) so that the carb can get warm and thaw out.

My personal experience with this sort of problem on a series truck from living on the prairies was to pull the carb and put it on the work bench - clean out the bowl and use some carb cleaner on the rest if it looked dirty. It was amazing the yuck that accumulates in the bowl (and the ice that can get in there as well)

Once you know the carb is clean and the fuel delivery system is good then you can look at other things such as vacuum leaks.

Good luck, hope this helps!

Rob
PS: If you do need to drain the gas I wouls suggest siphoning as much out as possible first before dropping the rest out of the bottom drain plug. Also, some hardware stores and marine suppliers sell filter screens for funnels that seperates water from gas - might be something to consider if you chose to filter your gas.

[larry emrick]

Rob, Gentlemen: It's 9 a.m. Sunday and I am still at it. I did drain the tank last night and still no improvement. I now have had a hot air heater on the back of the carb for about half an hour, enough to warm the carb body. Still starts perfectly on full choke but I noticed that as it is running at a fast idle the intake manifold is icing up on the outside. I popped off the big air intake hose and with the ignition off opened the choke and throttle manually to look into the carb. There is a liquid of some sort down there, presumably gas, but what also look like ice crystals. I have got the heater back on it but am trying to figure a way to get that liquid out of there. Back to the car port. Larry

[John]

Carb icing is a common problem with the Webber carb's installed on Land Rovers. I have been watching this thread and am surprised that nobody has yet suggested it to you. You can try shutting the engine off not long after you have gotten some heat into it, maybe after a long idle period or after a short run while it is still running pretty good on the choke, and letting the heat generated soak into the carb. Sometimes it will run fine after that. Otherwise you can search the web for the many creative solutions that others have tried in attempting to remedy the situation. You will find that after many attempts that some have opted for pitching the Webber in favour of a stock carb.

[larry emrick]

First off: Thanks to everyone who has contributed. Cross my fingers, but I just got it around the neighbourhood for the first time in days and it's idling nicely. So here's what I did: removed and checked all the hoses for cracks and leaks. They were all fine. Replaced the gas line filter (Lordco has a Fram replacement to the AC) and cleaned out the bowl. Drained the tank. Took the glass bowl off the fuel pump and cleaned it out; cleaned out the float bowl and put a little heater onto the intake for about two hours. I even put a few drops of gas line antifreeze directly into the carb. There was icing and water in just about every receptical I got at so there's little wonder it would not run. I am amazed it would even start. Even under normal conditions it runs so cold that it barely generates any heat even though I have partially blocked the rad intake. And most of my driving is short runs so it never does get a chance to warm up. Again, thanks to all who helped . Larry

[ANDYD]

Great to hear your up and running.

I had a Webber on my 2a, than never gave me any trouble (I was lucky I guess!) I remember there is a manifold heatsheild between the carb and the exhaust manifold. I would take mine off in the winter and put it back on in the summer. This would help to get some warmth to it on cold long winters!
Make sure you put it back in the summer cause they are prone to have fuel evaporation issues in the heat of summer!

cheers,
Andy

[DaveB]

I built additional heat shielding with an old cookie tin. It worked fairly well to direct heat from the exhaust up onto the carb.

Glad to hear you got it running and all the ice out of it.

cheers, Dave

[rick.m]

i will have my series IIA 109 at the EVENT, with what i replaced :"grrrrrr dmm webbbbb,rrr . WITH . if any one wants to drive the truck through the course. or to have a reminder of what we sreies truck owners go through, in our long suffering ownership of our rovers. ..come one come all.