Hello all,
Very new Jaguar owner here. I just purchased a '59 Mark IX, and went out today to check all fluids and familiarize myself with the car. I put the ignition key in, and switched the petrol switch from main tank to the off tank. It made a very funny, repetitive noise so I turned it back to the main tank and removed the ignition key. That's when I heard a liquid hitting the floor, and crawled under the car to find a good amount of fuel leaking out onto my garage from just to the left of the front passenger-side tire.
I tested it again, and same result...if I switch the tank, it dumps fuel onto my floor. Do I have a clogged line? I didn't crawl directly under the engine, but I could not find where the actual leak was originating.
Did I do something wrong, or do I need to have the fuel system checked out? Any help would be appreciated, thank you :)
Daniel
Submitted by easttennatm@ho… on Tue, 12/04/2007 - 22:22
Submitted by SE98-32482CJ on Tue, 12/04/2007 - 07:57
Mark IX dumping fuel when tank is switched...ideas?
Do not know what the outside temp is where you are but 80 is high for winter with casual driving--you should be more towards 70. Sounds like your cap is not holding pressuer which could cause that. As far as trash in the floats that can be an issue--but---one of the reasons I like to maintain cars in their orig. condition is they become easy to trouble shoot. Your car should have a screen filter at the bottom of each tank--it should have a s,all filter at the entry point of each carb. If both are present and in good condition trash will not be a problem to the float but could clog the filters--different problem. Good luck George Camp
Submitted by easttennatm@ho… on Sat, 12/01/2007 - 18:02
Mark IX dumping fuel when tank is switched...ideas?
Hey George,
That was definitely an issue, I ran it around the block for about 20 minutes today, and didn't have any fuel issues. I think it's still running rich, that might be cured with a carb adjustment though.
I finally found a cut-away diagram of the float bowl and carb, so I know what I'm looking at now. My mechanic friend says if there is garbage in the fuel tank and lines it could cause the problem to reoccur, so I'll keep my eye on it.
Last thing while I have you, at operating temperature my water temp gauge sits on about 80 degrees Celsius, and then when I park it a bit of steam/smoke escapes from under the radiator cap for a minute or two. Not a lot, just enough to be noticeable. The cap doesn't seal very tightly, as it's all original and getting a little tired.
Does 80 sound correct to you? I am planning on flushing the radiator completely and refilling as I noticed a bit of sludge build-up around the opening of the radiator fill. I'm guessing it looks the same down inside.
Thanks for the help!
Daniel
Submitted by SE98-32482CJ on Sat, 12/01/2007 - 07:56
Mark IX dumping fuel when tank is switched...ideas?
You have found the problem--make sure the float noes not have fuel in it--It should float high in the fuel. If there is no fuel in the float (shake it and listen) then put it back and check--you either have a sticky needle or a sunken float! George Camp
Submitted by easttennatm@ho… on Fri, 11/30/2007 - 18:32
Mark IX dumping fuel when tank is switched...ideas?
Thanks for the replies...
George, my neighbor suggested tapping the top of the bowl as well :)
Last night I removed the overflow pipe and top of the bowl, and although I couldn't remove the cap completely enough to get a clear view inside I did see a brass/gold-colored thing floating in the bowl. The bowl was full to the rim with gasoline.
I replaced the overflow pipe and lid, but did not start the car because of the amount of gas that had previously splashed out when I was removing the lid, and I haven't had time to look at it today but will get back to it tomorrow.
A couple questions:
-Is the bowl supposed to be full of gasoline, or is this because of the stuck float?
-If I turn the ignition on again and fuel does NOT dump onto the ground, does this mean the problem is fixed (at least until it sticks again?)
I'm really looking forward to learning to work on this car, but I honestly don't have a lot of mechanical experience. Thanks for the advice, I appreciate it!
Daniel
Submitted by SE98-32482CJ on Fri, 11/30/2007 - 06:07
Mark IX dumping fuel when tank is switched...ideas?
Daniel good job detecting the leak. Prior to spending all of your earnings on rebuild gently tap on the big nut that holds the over flow pipe on. If the car has sat for a long period the float needle can become stuck. If tapping does not work remove the top of the bowl--same nut and check that the float has not sunk. Bet is tapping will fix it--please feel free to send some portion of the saved rebuild cost to me--just kidding--good luck George Camp
Submitted by chris.johnston… on Thu, 11/29/2007 - 17:11
Mark IX dumping fuel when tank is switched...ideas?
I'm guessing that the 'carbs' need to be rebuilt, they are either HD6 or HD8 I think.Also the 'carb floats' are most likely full of gas. Get new fuel pumps and replace all fuel lines.
Submitted by easttennatm@ho… on Thu, 11/29/2007 - 16:56
Mark IX dumping fuel when tank is switched...ideas?
Update to my previous post...
I had someone else turn the ignition on so I could watch where the fuel was coming from. It is actually draining from a tube connected to a reservoir just below the left carb, and I guess that is a float valve of some sort that is stuck and causing the excess fuel to drain out?
So I know it's not a clogged fuel line or leak, and that's probably why the car is running very rich as well I assume.
Should be an easy fix, but I'm not terribly familiar with this car so any ideas, hints, or advice is still welcomed!
Thanks,
Daniel
As far as the cap not holding pressure, you're probably correct because as I stated before some steam escapes once I come to a rest. I'll replace the cap and seal and see if that helps the issue some.
Found another fuel problem, but this one wasn't related to the carb float. I noticed a strong gasoline smell in the car, and happened to check the trunk and found both sending units leaking gas from the bottom of their seals. This was discovered AFTER filling both my tanks full, about 20 gallons worth of gas :P
I've spent the past two days siphoning gas back out and into cans, and I've pulled both units and cleaned the edges up so I can reseal them. While I'm in there I'm going to replace all the rubber venting hoses (not sure of the actual name for these) since they are getting pretty old.
Working on the car is satisfying, I just don't want to get in over my head :) Thanks for the tips!
Daniel