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Tips
Tips

Holy Vapor Lock Batman!

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I DO have a charcoal canister. I recently replace the charcoal and the cotton filter in it, and it seemed to have good air flow through all of the fittings. I have this small gizmo in the trunk I've never messed with though. I think it's supposed to the the vapor sepparator? I haven't seen any replacements for this device, and I haven't seen anything in my Haynes manual that details how to service the device.

I have tried opening the fuel tank cap, but it never gives me the tell tale "inhale" when I do. Even after the car stalls, it opens up normally with no sudden inhale or exhaling of air.

I suppose I could try runninng with the float bowl to canister line disconnected to see if it makes a difference? Or maybe it'd be as simple as just blowing through the line to make sure there's no blockage?

Anyone here with a RB B care to commment on the ease or difficulty of filling the fuel tank? I have to barely squeeze a fuel pump handle to fill the tank. Most places, will shut off if I go faster than barely making the pump flow.
 
If it does happen again remove the gas cap and see if you get the gas to flow back in the filer again. (edit since you posted before I got my post in) The canister in the trunk(the vapor seperator) should be mounted vertical with the line from the tank on the bottom and the other line which goes to the charcoal canister on top. If it's laying on it side it may be full of gas and cutting off airflow back to the tank.

Maybe it the slightly different with the metal filler neck but once I can get the lovely cali pumps to pump it will go full bore till the auto cutoff.
 
And the green almost matches the yellow too don't it - /ubbthreads/images/graemlins/wink.gif
 
I just re-read some of the earlier posts and it's strange that the fuel filter fills back up on its own with the key off. Anyway, as Doc said earlier, are you SURE the fuel pump is working?

Also, check your plugs. If the car is running lean it will run hot. If your pump is going out or it is having a hard time supplying fuel it could cause your engine to run lean on fuel as well. If your lucky you might get two birds with one stone here.

/ubbthreads/images/graemlins/cheers.gif
 
You could have (and I've had this happen on a carburetted ford van 6 cylinder before) a rubber fuel line collapsing under the faster flow of the fuel at speed.
 
I'm nearly positive the pump is running. It can be a little diffiult to tell that it is running while the car is on and in traffic though. Then again, it could be one of those 'I always hear it so I automatically tune it out' type things, and only take note when I don't hear it. I always listen for it during my start up procedures, though.

I can only recall one situation where it wasn't running and that was due to a short back there, and it _really_ didn't want to run when that happened.
 
The only time I had delivery problems (after buying a new pump), the little plastic screen on the pickup tube was glazed over with old gas resin... But I could only get about a half mile before it would quit... then after several minutes with they key on (pumping fuel)... I could go another half mile. /ubbthreads/images/graemlins/smirk.gif Not nearly the same symptoms though.
 
[ QUOTE ]
the little plastic screen on the pickup tube was glazed over with old gas resin

[/ QUOTE ]

Or, trash in the tank that blocks the intake...or, the pump is losing its prime & the fuel line drains
 
Based on my experince, I would recheck the lines and pickup at the tank end first. I have had a similar sounding problem with one of my B's and it turned out to be the line coming out of the fuel pump, which was connected to an inline filter there. I had to remove the filter completely and replace that little piece of hose...and haven't had a problem since.

The no gas in the filter indicates that it is not vapor lock to me, anyhow /ubbthreads/images/graemlins/confused.gif

Bruce /ubbthreads/images/graemlins/cheers.gif
 
You know Bruce your are correct, fuel line somewhere between the filter and the tank is restricted. That indeed is the first order of business.

Clean tank and line, etc.
 
hmmm... thanks for all the tips guys. I changed from the stock SU pump to a Facet pump last year because I thought the pump was at fault. When I disconnet the fuel line from the carb and let it free flow, it seems to be on the 'low end' of having a good flow rate. I think it filled a 1 pint Mason jar around 25 seconds, I'm not sure. It's been a while since I did that test.

I'll have to do it again. This time with a portable gas tank so I can easil put it back into the car.

I can't help be think that the problem is somewhat related to heat though. The reason being that the fuel filter drains a lot faster on hot days than it does on cool days.

Anywho, I've noticed something else. It would seem that I'm not the only owner of this car to have fuel delivery problems. I've notice that someone had run rubber fuel line from the rear of the car all the way to the front of the car. That fuel line is not in use anymore, and has been corked at both ends. The hard fuel line (curently in use) in the car look like it could be original; it's nice and crusty looking on the outside. The PO tells me the fuel tank is "new", and indeed it looks a lot newer than the rest of the fuel system. But as many have pointed out in the past, that don't always make it "good".

I'll have to give the fuel system a thorough going over, when i don't have so much fuel to drain next weekend.

Thanks for again for the tips guys. I'll report back once I get the pick up checked out.
 
Fill a one gal gas can with fuel. Attach one end to carb fuel inlet with maybe 4 ft of hose, other end in gas can. Make sure gas can is higher than carbs. Give it a go, Don't forget to make sure no air in hose.

Attach hose to fuel pump inlet see what kind of output you get?
 
hmm? What does that do? Erm... just to make sure the car will run on a gravity-fed fuel delivery? Should I do that when the car starts mis-behaving?

The second check, is that connect the gas can to the fuel pump, to see if the fuel lines between the pump and carb are ok?

Sorry, if these sound like stupid questions, but I'm a little confused on what I'm checking with those, and when I should perform them.
 
yep your second question is yes. You had some question about the fuel line.

Forget the gravity fuel delivery, the second will work better.

Something in your case is keeping the fuel from getting to the Carbs, and I don't think it is vapor lock. I think you have a poorly pump, cloged line or junk in the tank or a bit of all there. In fact I think you said the entire fuel line is rubber hose? Bet it is going away inside and restricting the flow, try the gas can on the pump trick and see what kind of output you get and for how long, pump the whole gal through, should not take long.
 
I'm on my 3rd (according to Darrin) or 4th (according to me) fuel pump since April of 1994. It sat around from Oct of 94 to Nov 98.
So in 8.5 years of very light use maybe 10k miles 3 or 4 fuel pumps.
I read your first post and MOST of the replies and I'm convinced that a new fuel pump would fix your problem but maybe NOT the cause. So it might resurface.
 
Well I wish I could give you a more educated answer, but I have no clue.
Maybe I'll switch back to the SU pump after I get the bracket.
Also my gas mileage really inhales. 15 mpg maybe!!!
 
erm... Sorry, if i confused the matter. The hard lines are in use on my car. They are really old though.

Soft lines were run at some point in time. The soft lines are still on the car, but they are NOT in use.
 
[ QUOTE ]
erm... Sorry, if i confused the matter. The hard lines are in use on my car. They are really old though.

Soft lines were run at some point in time. The soft lines are still on the car, but they are NOT in use.

[/ QUOTE ]

If this were my car, I'd disconnect the fuel feed line at the tank and again where it crosses the firewall. Blow it out with a couple of bursts of compressed air. Do the same thing on the vapor return line between the charcoal canisters and the vapor seperator in the boot. Just make sure you disconnect the tubing on both ends; you don't want to blow crud back into the tank or the separator.

I'm on the same SU pump for the last 16 years.... tick tick tick tick, tick, t i c k... Replaced the diaphrgm once and reset the throw over, it is good as new. I hate the Facet pumps, they've no soul /ubbthreads/images/graemlins/devilgrin.gif
 
Scott!!! The silly soul-less Facet pump has allowed me to traverse the continent (the Eastern bits)!!! But I couldn't agree more that it is certainly soul-less. I am putting an SU back in service in lieu of the Facet. And a "spare" SU will be in th' boot from now on.
 
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