Alberta Land Rover Enthusiasts Club Forum
General => Technical Discussions => Topic started by: davis911s on August 01, 2017, 10:53 AM
I have the Land Rover out at the farm. It is acting very weird and the worst part is....it is sporadic
I am pretty sure it is fuel related. It will be running fine and then just stall out, engine will restart but stall out right away. It is like it is running out of fuel. (It has 1/2 tank) The hardest part is sometimes it will run just great, then stall, then run fine again a few minutes (3 minutes - 2 hours) later. It is NOT getting hot. It will act this way 30 seconds or 5 minutes into a drive, or it will drive 30 minutes continuous with no problems.
Also I do not believe it is terrain or bumpy roads, because it will act this way on level straight ground, or bumpy roads, but also will run fine on bumpy trails too
It has an electric fuel pump, but the switch is On, I can hear it running AND The fuel bowl is full.
I thought it may be flooding, but why sometimes and not others?
Dirty carb or filter that has something in it that is periodically blocking, then settles???
Thoughts?
Yep, the last part about stuff in the lines / filter.
I heard a story of a truck driver having similar problems and eventually it was traced to a condom in the fuel tank. :o The "F ing" thing would float around and when close enough, restrict fuel suction then float away with motion of the fuel. Must have sent the driver crazy trying to find the cause.
Also, the condenser can do strange things to the ignition as it fails.
In most cases they either work/don't work, but they can also fail intermittently due to heat, ie: run not bad while cool, fall off as they warm up.
I read one time that 50% of carb problems are actually ignition related.
Quote from: Chad M on August 02, 2017, 06:58 AM
Also, the condenser can do strange things to the ignition as it fails.
In most cases they either work/don't work, but they can also fail intermittently due to heat, ie: run not bad while cool, fall off as they warm up.
I read one time that 50% of carb problems are actually ignition related.
X2 on that. Had ign coils do the same intermittent thing too. Drives a guy crazy.
Shawn, I forgot to mention that I have a spare condenser if you want to swap it out.
Or, just a loose wire, bad fuse contact.... Especially if it dies suddenly and decisively. I think a blockage in the car would cause it to run poorly at times, other times stall out completely.
I've seen similar problems where there was a temporary reoccurring fuel blockage.
One time it was some crap floating in the tank and sucking up against the pickup tube intake.
The other time was a chunk on clear silicon in the float bowl that would suck up onto the main jet.
still no note of draining and cleaning the entire fuel system here? usually needed on older vehicles as a pre-startup check
UPDATE
I have replaced
Plugs
Points
Condensor
Coil
I have also cleaned and rebuild the carb, including checking the float height in the bowl is to spec.
Same issues!
I unhooked the fuel line and turned key on. Good fuel pressure and flow from the electric fuel pump. I added a clear in-line fuel filter just before the carb. This was more to visually see the fuel flow more that to use as a filter. I can see fuel going through as it idles. The filter never fills or even fills half way to where the fuel would be level to the input and output. It will start and I can watch fuel enter the filter as it idles. I can manipulate the rpms at the carb and it will run, But as soon as I put the transmission into gear it will die. It has died while idling too though, but will idle for 3 - 4minutes no problem but will die. It is definitely fuel related.
Fuel is good, I have not drained the tank looking for a condom yet
Sounds like you are getting air with the fuel. Check the pump suction lines.
Where are these lines? How do I check those? Thank you
This sounds awful familiar........ ???
Find the electric pump and look at the suction side lines for any damage.
Finally got a chance to look.
The electric fuel pump has 2 fuel lines. An input and an output. There are no blockages or kinks in anything I can see. The only other line is the electrical
First thing today I took the top off the carb. The bowl was empty. Turned on the key, could hear the electric fuel pump kick in and watch the fuel fill the carb. Turned key, Engine started right up.
While it was running I could see the fuel entering the clear filter I installed just prior to the carb.
Checked the glass bowl by the mechanical pump. It was full. The engine ran for about 2 minutes, (idled very nicely). While engine was running I watched the glass bowl, I could see air bubbles in the glass bowl 2 times during this 2 minutes, (fuel going in like a waterfall ?? sorry weird description) The glass bowl was completely full except the 2 times I could see bubbles where the level went down to maybe 3/4 full for a second or two.
Then the engine died. The glass bowl was full when it died. I took the top off the carb and the bowl was empty.
I turned the key on again and watched the fuel filter fill up, then it started right up again and did the same thing
2 options I am thinking
1- Since there is lots of fuel in the glass sediment bowl, but the fuel is not getting to the carb, it must be the mechanical fuel pump?? or;
2- Like Red90 said, the electric fuel pump is going and these air bubbles are causing like a vapour lock?
Thoughts?
Chad M stopped by, has a great idea. I am going to bypass the mechanical pump and run the fuel line direct from the electric pump to the carb and see if anything changes.
I do not know why the PO put in an electric pump, but I assume there was something wrong to start with. The other thing I do to know is if there is a diaphragm in the mechanical pump, or if he just bypassed it?
Hopefully will get a chance in the next week or 2 to check it out, but I am definitely getting closer
UPDATE
Did what Chad recommended. Bypassed the mechanical pump, so fuel goes from tank to electric pump and then direct to the carb. Works like a charm. I have only taken it for short drive, but it idled great for 10 minutes, and has started and idled 3 times since. Prior to this it only would idle for 2 minutes or so then die, so I assume all is well.
So with engine NOT running, the electric pump would push fuel all the way and fill the carb bowl. As soon as the engine was running, the mechanical pump would close to flow of fuel to the carb, the engine would burn off whatever was in the bowl and die due to lack of fuel.
I will buy a rebuild kit for the mech pump next time I make an order and rebuild it in warmer weather.
Thanks everybody
Make sure the fuel has not been making it into the crankcase. If the diaphragm failed it is possible.
Thanks Red. I checked the dipstick and did not see any indication of fuel in there. Good point, if fuel in there that would not be good