[AngelOfMurci]

Like I said in my write up and the other thread, the sender gasket is attached to the gas tank in an indented area that is approximately 2 inches lower than the top of the gas tank meaning when full, the gas level is above the gasket level, which means your gasket is seeping gas Into the indented area on the top of your gas tank. This is a very dangerous condition. Best to snake your camera or Boroscope in underneath the coolant expansion tank on the right side of your engine to see.

if so, the “while you’re in there” fix it list is fuel filters, fuel lines, sender? Or at least gasket, new coolant lines at least in that area, check power steering fluid reservoir.

Thanks for all the help.
Gonna definitely diagnose the issue.

 

[AngelOfMurci]

Like I said in my write up and the other thread, the sender gasket is attached to the gas tank in an indented area that is approximately 2 inches lower than the top of the gas tank meaning when full, the gas level is above the gasket level, which means your gasket is seeping gas Into the indented area on the top of your gas tank. This is a very dangerous condition. Best to snake your camera or Boroscope in underneath the coolant expansion tank on the right side of your engine to see.

if so, the “while you’re in there” fix it list is fuel filters, fuel lines, sender? Or at least gasket, new coolant lines at least in that area, check power steering fluid reservoir.

@DiabloClyde or others
what Do the gas caps on diablos look like?
Did Lamborghini just use the same cap for diablos, gallardos and Murcis?
My cap from my Murci does fit my Diablo roadster.

does your Diablo cap look like this? Thanks!

 

[DiabloClyde]

That does not look like an original Diablo bit it might be from a 99? These photos are for my 97 as well as my 08 gallardo.

 

[AngelOfMurci]

That does not look like an original Diablo bit it might be from a 99? These photos are for my 97 as well as my 08 gallardo.

My cap on the 99 roadster is made of metal
Just doesn’t look like it would come from a 99 roadster.

 

[AngelOfMurci]

@DiabloClyde
I finally had time to get into my gas tank area. Ran a $100 reticulating borescope in there.

Snapped this pic. Holy moly, lots of gravel and what appears to be a few nuggets of gold!!! Wow. Must be my lucky day 😎

There appears to be a torn piece of rubber surrounding the disc.

according to this Bullstuff diagram, it’s the fuel filler cap. Huh? I would think some hoses or tube would be coming out of it? What’s going on? The area surrounding it is depressed by an inch. Any thoughts are much appreciated.

 

[AngelOfMurci]

@DiabloClyde
I finally had time to get into my gas tank area. Ran a $100 reticulating borescope in there.

View attachment 334747


Snapped this pic. Holy moly, lots of gravel and what appears to be a few nuggets of gold!!! Wow. Must be my lucky day 😎

There appears to be a torn piece of rubber surrounding the disc.

View attachment 334745

according to this Bullstuff diagram, it’s the fuel filler cap. Huh? I would think some hoses or tube would be coming out of it? What’s going on? The area surrounding it is depressed by an inch. Any thoughts are much appreciated.
View attachment 334746

Or are you saying to look at the fuel level gauge depressed area?

 

[DiabloClyde]

Part number 31 is the gasket that secures the fuel sender unit, that’s the long tube. You are looking at the wrong indentation.

 

[AngelOfMurci]

Part number 31 is the gasket that secures the fuel sender unit, that’s the long tube. You are looking at the wrong indentation.

Ok, on Sunday I will do another inspection.
Thanks!!!

 

[AngelOfMurci]

Ok, on Sunday I will do another inspection.
Thanks!!!

Got some more pics of the fuel filler area. There does appear to be discoloration around the tank where the filler connects to the tank.

I’m going to buy a new gasket. On Bullstuff they call if a fuel dimmer seal. Strange.

when I open up the area I will fill the tank and see exactly where the leak is coming from.

 

[DiabloClyde]

Angel, please go back and read what I wrote! I didn’t say the filler tube, and I didn’t say the second indentation area, I said the sender — the fuel gauge tube mechanism is called a sender — on the top underneath the fuel filter! It is part #31 in your diagram above.

 

[AngelOfMurci]

Angel, please go back and read what I wrote! I didn’t say the filler tube, and I didn’t say the second indentation area, I said the sender — the fuel gauge tube mechanism is called a sender — on the top underneath the fuel filter! It is part #31 in your diagram above.

Aaah! There’s a reason it took me 7 years to get a 4 year degree 😜

 

[DiabloClyde]

Angel, rereading my post above I didn’t mean to bust your chops. I just recognize that this is a very serious issue. Please please check properly. Take photos and let us know!

 

[AngelOfMurci]

Angel, rereading my post above I didn’t mean to bust your chops. I just recognize that this is a very serious issue. Please please check properly. Take photos and let us know!

I’m just doing a lot of preliminary work before I start taking everything apart. What normally takes 4 hours, will probably take an entire week. Access looks horrible.
Ps
Lost my chops in college. Nothing phases me… except a bad beat on the river 😜

 

[AngelOfMurci]

I’m just doing a lot of preliminary work before I start taking everything apart. What normally takes 4 hours, will probably take an entire week. Access looks horrible.
Ps
Lost my chops in college. Nothing phases me… except a bad beat on the river 😜

It looks like the Diablo has had iterative designs. These 2 do not match the part number on bullstuff.
however, one can see the design with a recessed edge going off the edge would be a proper design. A better design would have a catch canal diverting the gas seepage onto the ground.

 

[AngelOfMurci]

@DiabloClyde @Sledge4.2
Do you guys stick to OEM filters or use cross referenced filters?
I ask because there’s a thread saying they use :


Replacement Diablo fuel filters

I found replacement fuel filters are available from NAPA.
a compatable filter for the Weber-FI-02/2 is a Napa Gold 3008.

I also found the Napa 3248 compatible for the lower pair of filters.

 

[DiabloClyde]

I used the Webbers but I’m sure Napa replacement would be just fine. It’s a very straightforward fuel filter. Please note the main filters are on the top of the tank, but there are also two small pre-filters located underneath the tank where the fuel comes out. Those are a mess to replace, because the tank must be fully empty and even then you’re going to get gas in your face. The filters up top are easier and less gas. Use the absorbent waterproof pads that you can find on Amazon similar to a puppy training pad and them around before you take that filter off. Obviously, don’t use power tools.

The first gas tank photo above is what I have in my 97. Needless to say it has a little cup indentation where is my fuel puddled. If you have the later gas tank, it will run down the front of the gas tank in between the gas tank and the passenger seat firewall and will likely not hit the ground. It will collect on the frame covers underneath the car. I had to remove mine by drilling out rivets to find that there was fuel puddled in there as well. It makes a real mess of the under coating, which needs to then be cleaned off and re-sprayed before returning the panel back on.

in looking at both of the gas tank photos you posted I do see another problem. Eventually the filler tube, which is on a proximately 45° angle also has a gasket and that filler tube gasket is also below the level of fuel on a full tank. Overtime I suspect that gasket will also need to be replaced. If you are in that area, might as well replace that gasket as well.

 

[AngelOfMurci]

I used the Webbers but I’m sure Napa replacement would be just fine. It’s a very straightforward fuel filter. Please note the main filters are on the top of the tank, but there are also two small pre-filters located underneath the tank where the fuel comes out. Those are a mess to replace, because the tank must be fully empty and even then you’re going to get gas in your face. The filters up top are easier and less gas. Use the absorbent waterproof pads that you can find on Amazon similar to a puppy training pad and them around before you take that filter off. Obviously, don’t use power tools.

The first gas tank photo above is what I have in my 97. Needless to say it has a little cup indentation where is my fuel puddled. If you have the later gas tank, it will run down the front of the gas tank in between the gas tank and the passenger seat firewall and will likely not hit the ground. It will collect on the frame covers underneath the car. I had to remove mine by drilling out rivets to find that there was fuel puddled in there as well. It makes a real mess of the under coating, which needs to then be cleaned off and re-sprayed before returning the panel back on.

in looking at both of the gas tank photos you posted I do see another problem. Eventually the filler tube, which is on a proximately 45° angle also has a gasket and that filler tube gasket is also below the level of fuel on a full tank. Overtime I suspect that gasket will also need to be replaced. If you are in that area, might as well replace that gasket as well.

Thanks for all the advice…
I’ve just order 4 of each gaskets. I like having multiple backups of all cheap items. That way when they go NLA, I have plenty.

whenever I work on fuel lines/filters, I roll the vehicle out of the garage. No use risking setting the house on fire 😜

are there any special tools for replacing gaskets/fuel filters and removing coolant tank?

thanks!

 

[AngelOfMurci]

I used the Webbers but I’m sure Napa replacement would be just fine. It’s a very straightforward fuel filter. Please note the main filters are on the top of the tank, but there are also two small pre-filters located underneath the tank where the fuel comes out. Those are a mess to replace, because the tank must be fully empty and even then you’re going to get gas in your face. The filters up top are easier and less gas. Use the absorbent waterproof pads that you can find on Amazon similar to a puppy training pad and them around before you take that filter off. Obviously, don’t use power tools.

The first gas tank photo above is what I have in my 97. Needless to say it has a little cup indentation where is my fuel puddled. If you have the later gas tank, it will run down the front of the gas tank in between the gas tank and the passenger seat firewall and will likely not hit the ground. It will collect on the frame covers underneath the car. I had to remove mine by drilling out rivets to find that there was fuel puddled in there as well. It makes a real mess of the under coating, which needs to then be cleaned off and re-sprayed before returning the panel back on.

in looking at both of the gas tank photos you posted I do see another problem. Eventually the filler tube, which is on a proximately 45° angle also has a gasket and that filler tube gasket is also below the level of fuel on a full tank. Overtime I suspect that gasket will also need to be replaced. If you are in that area, might as well replace that gasket as well.

Received all the parts.
Lamborghini should have made the filler and sender connections the same diameter. That way they could have used the same gaskets, bolts, bolt pattern , etc…. Saving money in design and fabrication.

can I assume the coolant tank needs to be drained? I.e. it can’t just be disconnected from mounting bracket and slide over[edit: never mind , just reread what you posted. Looks like it’s gotta be drained and removed]

fyi, I siphoned the tank, it looks like the internals of the tank are such that it is divided and having holes along the partitions. I believe that’s to prevents large amounts of gas from slushing around during cornering and braking.

 

[AngelOfMurci]

Here’s a pic of the fuel filler area(from inside the gas tank). Note the cable you see is my borescope camera cable. I was able to reticulate the camera 180 degrees to get the pic/video.

note: there is a little discoloration on a couple bolt heads. Not too sure if that’s of any significance. Ps this site is having major issue uploading pics. Gives errors, etc.

 

[Giallous?]

Thank you everyone. For future reference if anyone is in my situation, remove the passenger rear tire and fenders. They are attached with maybe 12 bolts 8mm and 10mm, very simple to remove. The photos attached are the view you will get with the rear passenger fender removed. It is significantly easier to access this location than from under the engine bonnet above.

Wow. That is one of the most useful and helpful posts in the history of automotive forums.