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Discussion Starter #1
How does one check for gas leaks on an 88 Daytona 2.5 liter? I did take the air cleaner off and noticed the air filter was pretty dirty so I took it out and will get a new one. The smell seems to be coming from the front of the car and when I sniffed around the engine when I got close to the throttle body is where I smelled the strongest odor gasoline (is this normal I don't know). Any how I just need to know the procedure so I can do it myself. Besides hoses, does the throttle body have a gasket that could be getting bad? After I drove it 5 miles yesterday, then parked it in the garage, when I got out of the Daytona I smelled an extremely strong smell of gasoline like someone had dumped it on the floor. I looked under the car but saw NOTHING on the concrete! UGH.
 

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The most likely source of leakage in that area are the fuel supply and return hoses. They come up along the passenger side near the firewall and are U-shaped, before they connect to the throttle body. They are metal lines which have a section about 18 inches long of rubber fuel injection hose crimped on, then metal to the throttle body. Look with a strong flashlight beam, and flex the hoses with the engine running (and with goggles on). You will probably see hundreds of tiny cracks in the rubber hoses, and maybe even some traces of liquid gas oozing.

I reworked them by slowly and painstakingly cutting the metal crimps with a hacksaw blade, after having disconnected the fuel filter and let the lines drain. Then I bought SAE 30R9 fuel injection hose and doubled up on fuel injection clamps to replace the rubber sections. Don't use SAE 30R6 or 30R7, they are not rated high enough for the pressure of the supply line.
 
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Discussion Starter #3
So most likely it would be those rubber hoses that need replacing. This is where I smelled the worst of the gas smell was the passenger side. And when lifted the hood later afterwards I smelled gas on that side again.

So the replacement of those rubber hoses does not sound easy? Who in the world would design metal clamps that have to be removed by a hack saw? Sheesh!!

How long are the rubber hose sections approximately? Thanks for the reply this was very helpful.


Bob Lincoln said:
The most likely source of leakage in that area are the fuel supply and return hoses. They come up along the passenger side near the firewall and are U-shaped, before they connect to the throttle body. They are metal lines which have a section about 18 inches long of rubber fuel injection hose crimped on, then metal to the throttle body. Look with a strong flashlight beam, and flex the hoses with the engine running (and with goggles on). You will probably see hundreds of tiny cracks in the rubber hoses, and maybe even some traces of liquid gas oozing.

I reworked them by slowly and painstakingly cutting the metal crimps with a hacksaw blade, after having disconnected the fuel filter and let the lines drain. Then I bought SAE 30R9 fuel injection hose and doubled up on fuel injection clamps to replace the rubber sections. Don't use SAE 30R6 or 30R7, they are not rated high enough for the pressure of the supply line.
 

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The hoses are replaceable, they have a quick-release at the bottom, but my experience is that they are difficult to remove. And I don't think replacements are available.

It's not hard, just tedious, to cut off the clamps. You will need about 18 inches per hose, but plan for 24 so you don't end up short. The supply is 5/16" inside diameter, the return line is 1/4" inside diameter. Typically this hose costs a couple of dollars per foot, so you're looking at about $10 plus the clamps. Supply clamp is FV-15 size, return is FV-13, and if you double up, you will need 4 clamps of each size.
 

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These hose ends were crimped because no repair was recommended.
New male/female ends are available to make your own:
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You want only high-pressure EFI fuel hose as stated. Use no other hose type.
Use only EFI or 'aviation-style' clamps.
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Do not use regular screw clamps.
Many shops will refuse to repair fuel hoses due to possible liability from leaks or fires.
If the new parts are available. Replace them.
Do you see wetness? Are the steel lines rusted under the car?
 
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Discussion Starter #7
What I do not understand is how the shop missed this last year. I have been smelling gas on and off and it's been getting worse. I am lucky it did not catch on fire. The metal lines were inspected by the shop, but obviously they did not look at the rubber hose sections. When I bent one of them, I saw TONS of cracks!!! I did not even bother to start the car because I figured this has to be it due to where the gas smell was coming from.
 

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Are they wet while running?
 

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Discussion Starter #9
I will check it tomorrow and see if they get wet while running.


ImperialCrown said:
Are they wet while running?
 

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Even if they aren't, with tons of cracks, they will. Best to avoid the fire and do them now.
 
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Discussion Starter #11
I agree, Bob.


Bob Lincoln said:
Even if they aren't, with tons of cracks, they will. Best to avoid the fire and do them now.
 

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Discussion Starter #12
How many rubber hoses will need to be replaced? I see two rubber sections in the photo between metal lines. Please help me all to be specific on what will need to be replaced as we are going to get someone this weekend to do this. I just want to make sure I get the right hoses. Thanks.
 

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You should buy a two-foot length each of 5/16" diameter and 1/4" diameter fuel injection hose that is rated SAE 30R9 or SAE 100R6. For fuel injection band clamps, buy 4 each of FV-15 size (15mm) and 4 each of FV-13 size (13mm). This way, you can double up with two clamps on each end of the hose to guarantee no leaks.

Pressure in the lines will bleed down if not cranked for a few days, but you can also unplug the fuel injector and jumper the battery across it for no more than a second or two (be careful not to short across the battery), to open the injector and dump fuel pressure.

I used a hacksaw to cut the crimps off, which did take awhile (more than an hour), for safety. There may be other creative methods that won't generate a spark.
 

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The hose clamps are just Fuel Injection type screw clamps and if they are too rusty to remove after soaking with penetrating oil, I just use a large angle side wire cutter.
 

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Discussion Starter #15
Thanks for the list, Bob. Well, I thought it was going to get done this weekend not sure if it is now. Any ways, I have the list :)


Scstables said:
How many rubber hoses will need to be replaced? I see two rubber sections in the photo between metal lines. Please help me all to be specific on what will need to be replaced as we are going to get someone this weekend to do this. I just want to make sure I get the right hoses. Thanks.
 

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Discussion Starter #16
Found the culprit, it was a 3 inch long tiny rubber fuel hose that connected to the throttle body. That was replaced and now there is NO gas smell when the car is running. Happy! I have the hose to replace the other longer rubber sections, that is next on the list. Right now there is no fuel leaking from the longer fatter ones, but I am sure that could happen if those don't get replaced soon.
 
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