Question does Roadster fuel tank have baffles??

[Jeff_J.]

We'll in finally driving my MK4, at least for a 500 mile shakedown before paint. I ran across a odd situation. I was changing highways on an overpass, while I was 3/4 of the way up the long right hand curve leading to the top of the overpass the car sputtered and stalled, then refired when it slowed, I'm thinking the fuel in the tank sloshed over to the PS and the pump ran dry.. I initially though I didn't have enough fuel in it but it did it again with a 1/4 full tank. It hasn't sputtered at any other time than the long right had turn. My initial startup in the garage had maybe 1/16 of a tank so I'm thinking the pump pickup is low enough, I'm sure one of the experienced guys will know if the fuel tanks are baffled if someone has run into this before?? Can't drive the car only making left hand turns... I'm looking for some insight here before digging deeper.
Thanks in advance for the input.

Jeff J.

[Jeff Kleiner]

Not really a baffle per se but there is an approximately 3” high by 8” to 10” square “box” around the pickup that is supposed to help contain fuel around the pickup when it sloshes. It has openings at the bottom so that fuel can move in or out slowly however if you’re running low it’s not going to be containing much so I could see the pickup becoming uncovered.

Jeff

[edwardb]

1/16 full I could understand the pickup getting uncovered. 1/4 full not so much. But still possible as Jeff described. I've used those tanks in multiple builds and haven't had an issue for street driving. I typically always fill back up when the gauge is at 1/4 full. Maybe that's all you need to do.

[Jeff_J.]

Thanks for the info / input guys. I haven't had the problem other then on the corner which makes me wonder about the pickup. In for alignment tomorrow and a little more shakedown before the body comes off for what I hope will be the last time, I may take the opportunity to measure the depth of the tank vs the pickup just to be sure I'm all the way there..
J.

[Avalanche325]

On my gauge and others that I know, 1/4 means almost empty. I can literally see the gauge moving.

[boat737]

On my gauge and others that I know, 1/4 means almost empty. I can literally see the gauge moving.

Man oh man, aint that the truth. That last 1/4 on the fuel gauge starts acting like the speedo or tach.

[StangRacer]

I used the factory Mustang fuel tank in my 94 GT CMC race car and never had any issues with fuel sloshing away from the pickup. Many in CMC use the factory tank and I don't recall anyone else having the issue either... some Sunday races would be 45 minutes and would be down to around a 1/4 tank by the end of the race... Some did have the baffle in the tank break loose which would result in the symptom you describe. It may be worth checking...

[Flip Smiley]

My baffle broke loss in the stock donor Mustang tank I used. Caused some sloshing issues.
I purchased and installed a new one.

[runamuk]

The pick up is on the right hand side of the tank, so in a long sweeping right hand turn the fuel will slosh to that side. If you pull the pick up out of the tank, shine a flashlight inside to look at the baffling that surrounds the fuel pick up.

[rich grsc]

The pick up is on the right hand side of the tank, so in a long sweeping right hand turn the fuel will slosh to that side. If you pull the pick up out of the tank, shine a flashlight inside to look at the baffling that surrounds the fuel pick up.

Actually it will move to left side of the tank, not the right

[CraigS]

I would definitely take a look at it. Just surmising here but who knows who makes the current tank and whether it is made to original specs or not? I could see that, in the constant striving for low prices, that baffle being left out.

[Kbl7td]

I would definitely take a look at it. Just surmising here but who knows who makes the current tank and whether it is made to original specs or not? I could see that, in the constant striving for low prices, that baffle being left out.

Bought my tank from eBay, the “box” was still in there. In fact most should know because it makes installing the pump more of a challenge.

[Jeff_J.]

I'm using an Aeromotive Stealth, in tank pump and hangar/pickup so I'm kinda off on my own here. I'll measure the depth of the tank against the length of the pickup at some point just to know what's going on.
J.

[cfriedman67]

I Had the same exact problem and what cured it was reseating the fuel pump in the tank. I think mine might have been slightly angled and not sitting exactly flush with the tank. It was also recommended to get a Holley Hyrdramat which I did but never installed it.

[Rdone585]

If the baffel / box does brake loose you will get metal particles introduced in your fuel lines. My fuel filter would collect them and when they built up enough it would starve the carb for fuel. It took me a while to find the root cause - the baffel sliding around inside the tank. I discovered that fact when I jacked one side of the car and heard it slide inside the tank. Replaced the tank, both fuel filters, and thoroughly flushed the lines - problem solved.

[BrewCityCobra]

We'll in finally driving my MK4, at least for a 500 mile shakedown before paint. I ran across a odd situation. I was changing highways on an overpass, while I was 3/4 of the way up the long right hand curve leading to the top of the overpass the car sputtered and stalled, then refired when it slowed, I'm thinking the fuel in the tank sloshed over to the PS and the pump ran dry.. I initially though I didn't have enough fuel in it but it did it again with a 1/4 full tank. It hasn't sputtered at any other time than the long right had turn. My initial startup in the garage had maybe 1/16 of a tank so I'm thinking the pump pickup is low enough, I'm sure one of the experienced guys will know if the fuel tanks are baffled if someone has run into this before?? Can't drive the car only making left hand turns... I'm looking for some insight here before digging deeper.
Thanks in advance for the input.

Jeff J.

Well this is a bit concerning for my aspirations of hitting up Road America once my car is complete. The carousel might be interesting.

I guess keep plenty of fuel in the car is the obvious solution there.

[Rdone585]

BrewCity, you'll be fine at RA, just top off the tank after each 20 min session. I would run a little less than a gallon per lap (4 mile track) and about 8 laps per session.