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I guys.
I finally got round to looking into my fuel issue, a local bug guru tells me that the pump should measure 3.5 pounds at the carb. Mine reads 5 pounds or it did should I say. I adjusted the throw of the pump by placing two more gaskets twixt the pump body and the motor, that brought the pressure right to 3.5 pounds. Next stop is the float height. Adjustable with shims/washers I am told. Any advice guys?
The journey continues with the TDr. As does the dream of a Coast to coast run!
John the Brit
3.5 pounds is darned near perfect. If you don’t need to mess with the float, let it be and see how she runs.
Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The ShackI’d try running with the new pressure for a while first. I’ve never had to mess with the float in mine.
Hi Guys,
I seem to still have the same issue after reducing the fuel pump pressure. What happens is the fuel still drops into the motor after it has been shut off. The only way to start the car is to floor the throttle/crank it for a while and it will limp to life because it has so much fuel in the cylinders. The PO told me about this before I purchased the car. He replaced the fuel pump, carb and fitted a carbon tank to the gas tank at the time but none of these “fixes” worked. Is there a measurement for the float height?
John
Does your carb have a fuel shutoff (aka anti-dieseling) solenoid on it? Does it work? I’too, have never had float issues with a stock Soles carb..
Early FF TDr on 69 VW pan
Slowly coming back from the ashes...The measurement for the float height is included in the carb rebuild kit. $20 I think. However, from what you just said it may be the fuel cut-off solenoid. That’s supposed to be electrically opened and spring loaded closed. Its located on the bottom left side of the carb and should have a black wire going to it from the coil. When you turn the key on (don’t start it) you should hear a click from the solenoid being pulled open. If that is working then all that’s left is the float adjustment. What carb do you have?
Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The ShackHi Guys
I have a PICT 34 on the car with the anti run on valve fitted. I took the valve out and tried it on a battery. It will work intermittently. Doesn’t that valve merely open an airway to help shut the engine down. Im not sure how or why that would cause the excess fuel. I have a new valve on the way, the local guys were out of stock. Thanks for the help.
John
No, that solenoid shuts off the flow of fuel to the main jet in the carb. It is spring-loaded, and the solenoid only allows fuel to flow through the carb when the ignition switch is on. Turn the ignition off, and the fuel stops flowing, preventing engine run-on, dripping etc.
Early FF TDr on 69 VW pan
Slowly coming back from the ashes...Hi Guys.
Thanks Kent that clears that up for me. It was the bug guys that told me that it was a solenoid aaair bleed valve. Incidentally he also stated that none of our cars needed the caster shims, unless the vehicle had only been lowered in the front and in doing so change the caster angle on the front. He also added that if the car were to be lowered both front and back the car would need no such work.
Interesting. John
Well I also disagree with his statement about caster shims if both the front and rear have been lowered. Lowering or raising the rear has little effect on the caster of the front wheels – it’s the change in ride height and resulting angle of the front torsion/trailing arms. The height of the rear has a tiny impact on the angle, but not much…
The build manuals for most of the kits here call decambering the rear to lower it, in addition to lowering the front. Yet, several folks have found that the front caster adjustments needed are outside the range of the built-in adjustments, and require shimming the lower front torsion tube…
Perhaps he is used to lowering the front of stock-bodied bugs using “dropped spindles” rather than the cut/ reweld method in the TDr build manuals, or the highly recommended removal of the short leaves in the front torsion bar stacks. Using dropped spindles does not change the angle of the torsion arms, they simply move the wheel spindles up higher. The other two methods coomon on TDrs changes the angles. Removing leaves from the torsion bar stack is recommended because it changes (softens) the front springs to correspond with the lower weight of the fiberglass TDr and the changed seating position. KentT2015-06-05 19:52:48
Early FF TDr on 69 VW pan
Slowly coming back from the ashes...Hi Kent. very interesting observation. This begs the question as to what exactly is the optimum ride height and where does one measure it to and from. In a normal bodied vehicle for example you would measure from the centre of the front spindle to the bottom edge of the fender. giving measurement X. In theory and mass production that number is going to be the same. Give or take a tad bearing in mind factory limits and fits. With our cars where there are numerous variables such as fender fitment and even the wheels used etc where would be the common factor/ From ground to the floor? That issnt even taking into consideration the aesthetics and who built it.
John
John, I think that you are missing the point here. Kent’s discussion is about the height of the chassis as this affects the angles that the torsion bars and the front end geometry. This has nothing to do with the height of the fenders or the body.
I believe that the VW chassis (from the ground up to the floor pan on level ground) is supposed to be about 7-1/2″, although I can’t remember what my source of information is.
At Carlisle I bought some caster shims and in a couple of weeks, plan to try them out as an experiment to see if they make a noticeable change in the stability of the car in high speeds and cross wind buffeting. Ed’s a fan and he’s one of the people on the forum that I listen carefully to. Stay tuned for the results of my test.
(Now is when Paul, rightly, is going to suggest that this whole discussion about ride height and front end alignment be moved to another thread since it has nothing to do with “fuel pump pressure”.)
Reading my mind Roy!
Well played!
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
Hi Guys
Paul please accept my humble apologies for getting off task within this thread.
Thanks
John
Getting back to the Carb on the air cooled VW the idle cut solenoid ( anti=dieseling) only cuts the fuel off to the low speed circuit in the carb, it has no effect on fuel percolating into the hot engine after shutdown. see these pictures
Note from Paul: I cleaned this up by making the “see these pictures” the link instead of that very long search url.
PMOSSBERG2015-06-06 11:56:33
It actually cuts off the idle air bypass circuit, restricting the air to the engine ,slowing it down to prevent run-on.
BritinaAz wrote:Paul please accept my humble apologies for getting off task within this thread.Thanks
John
No worries John. Normal forum stuff…avoiding too much thread drift makes things easier to find in the future. We’re creating a legacy here for people restoring our cars fifty years after we’re gone. Or maybe I’m dreaming.
PMOSSBERG2015-06-06 12:00:24
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
Hi guys
So here is the update so far. The shut off valve has been replaced so the car now idles fine and doesn’t run on etc. The fuel still runs into the engine after you shut it off so no improvement there. I think that only leaves me with the float height being at fault ??. All work on the car has come to a halt for few weeks as I have now broken the bones in the back of my hand and its now in a full cast. grgrgrrgrggr frustration abounds!
John the Brit
Well some improvement is better than none! I always hate when I am chasing a problem and replace things that don’t actually affect anything!
Ouch! Hope your hand heals quickly!!!With the float level, you may not have to adjust it, but make sure the little plastic retainer is in the right way. See this picture for how it should be. I put mine in backwards once and it caused the same issue where it would flood after shut-off.I’ll assume that you are going to rebuild the carb. After you do and before re-installing on the manifold, turn the carb upside down and blow into the fuel inlet. It will give you some confidence that the float is actually going to stop fuel when the bowl is “full”.
(As a side benefit, it takes me back 60+ years to when I used to siphon gas out of my dad’s car before going over to my girlfriend’s house.)Hi Guys.
Thanks for the help. right now the arm wont let me do anything, I cant even hold a wrench or screwdriver except if I jam it between the cast and my palm. We shall see.
John
John. Sorry about your arm. I feel you pain…only at my shoulder. But it’ll heal and you’ll be back at it.
Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The ShackHi Guys.
Well 4 days without doing anything is enough. The idle vale has been changed out with no improvement to the gas dropping into the cylinders on shut off. Fuel pressure lowered from 5 pounds to 3.5 pounds. No change, placed an extra washer under the needle vale in the float chamber. Again no change but noted that the valve was not the original type, it had been replaced with a grose jet. Replaced the grose jet with a new original type but left the two washers under its seat. A quick look down the carb throat and it looks better with no fuel flooding everywhere. By this time the hand is telling me to quit being stupid and rest it like I was told.!! I had to give up for today but I am hopefull, Needs further investigation. Thanks for listening.
John the Brit
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