On 3/2/2011 5:41 PM, Gene wrote:
On Tue, 01 Mar 2011 19:59:01 -0500, L wrote:

Google results show differing opinions. Has anyone used Teflon tape
without success on a fuel line thread?

TIA,
Larry
FIRST and FOREMOST.... teflon ONLY works on TAPERED threads. If it
isn't a tapered thread.... forget the teflon (or any other sealant..
fix what is wrong).

There are different formulations of "teflon" for different
applications. For fuel, a "non-white" tape is probably called for.
Don't use the wrong kind. Not all tapes are created equal.

Don't put ANY tape on the first 1-2 threads.

There are semi-liquid thread sealants that are better than the tape.
Globs of pipe dope don't seal better; don't put pipe dope on the first
1-2 threads.





I might be wrong but aren't you supposed to use double flared on metal
fittings? I don't think compression or pipe thread is allowed.

wrote:
On Tue, 01 Mar 2011 19:59:01 -0500, L wrote:


Google results show differing opinions. Has anyone used Teflon tape
without success on a fuel line thread?

TIA,
Larry

Yes but only in front of the last filter. In my case there are 2
before you get to the fuel pumps and one more before you get to the
injectors (2 in the motor)
The tape won't be hurt but if you pinch off a piece in the fuel flow
it will cause problems if you don't catch it. That is also why a lot
of "gas" (natural/propane) guys use dope.

I'm not worried about a piece getting into the fuel line. If it
dissolved in the gas will it still be large enough to foul my injectors?

I_am_Tosk wrote:
In ,
says...

On Wed, 2 Mar 2011 07:09:12 -0500, wrote:


GreaT question. I have always thought teflon tape was impervious to
everything.

It's not, diesel mechanics never use teflon tape for anything because
small pieces of it can break off and clog injectors. They use lliquid
sealants like Permatex or Loctite instead.

I suppose the new Loctite tape is a no-no with Diesels too?

I would not use it downstream of the filters. Liquid sealant is
actually easier to use than tape in my experience. Removal is no
problem if you use the right stuff.

Did the op suggest why he wants to use the "wrong" stuff when the right
stuff is so easy?

The op - me - was unaware of the right stuff. I'm familiar with pipe
dope but I don't keep it around the house and wouldn't have thought it
would be any better.

Gene wrote:
On Tue, 01 Mar 2011 19:59:01 -0500, L wrote:


Google results show differing opinions. Has anyone used Teflon tape
without success on a fuel line thread?

TIA,
Larry

FIRST and FOREMOST.... teflon ONLY works on TAPERED threads. If it
isn't a tapered thread.... forget the teflon (or any other sealant..
fix what is wrong).

There are different formulations of "teflon" for different
applications. For fuel, a "non-white" tape is probably called for.
Don't use the wrong kind. Not all tapes are created equal.

Don't put ANY tape on the first 1-2 threads.

There are semi-liquid thread sealants that are better than the tape.
Globs of pipe dope don't seal better; don't put pipe dope on the first
1-2 threads.






They are tapered threads. It is a fuel line with the correct fittings.

Boating All Out wrote:
In ,
says...

On Tue, 01 Mar 2011 19:59:01 -0500, L wrote:


Google results show differing opinions. Has anyone used Teflon tape
without success on a fuel line thread?

TIA,
Larry

FIRST and FOREMOST.... teflon ONLY works on TAPERED threads. If it
isn't a tapered thread.... forget the teflon (or any other sealant..
fix what is wrong).


Right. Most gasoline fittings are flared.
Teflon tape is for NPT fittings.



There are different formulations of "teflon" for different
applications. For fuel, a "non-white" tape is probably called for.
Don't use the wrong kind. Not all tapes are created equal.


Right.


Don't put ANY tape on the first 1-2 threads.


Right. And it easier to avoid the first threads with tape than it is
with dope. The argument about using not using tape because it can enter
the line is bogus. Improperly applied dope does the same.


There are semi-liquid thread sealants that are better than the tape.
Globs of pipe dope don't seal better; don't put pipe dope on the first
1-2 threads.

Right. But unless NPT, gasoline fittings will be flared or o-ring.
Neither needs tape or dope.



The fittings I replaced were not flared and the larger, replacement
fittings are also not flared.

In article ,
says...

I_am_Tosk wrote:
In ,
says...

On Wed, 2 Mar 2011 07:09:12 -0500, wrote:


GreaT question. I have always thought teflon tape was impervious to
everything.

It's not, diesel mechanics never use teflon tape for anything because
small pieces of it can break off and clog injectors. They use lliquid
sealants like Permatex or Loctite instead.

I suppose the new Loctite tape is a no-no with Diesels too?

I would not use it downstream of the filters. Liquid sealant is
actually easier to use than tape in my experience. Removal is no
problem if you use the right stuff.

Did the op suggest why he wants to use the "wrong" stuff when the right
stuff is so easy?

The op - me - was unaware of the right stuff. I'm familiar with pipe
dope but I don't keep it around the house and wouldn't have thought it
would be any better.

Ahhh, makes sense now.

HenryK wrote:
On 3/2/2011 5:41 PM, Gene wrote:
On Tue, 01 Mar 2011 19:59:01 -0500, L wrote:

Google results show differing opinions. Has anyone used Teflon tape
without success on a fuel line thread?

TIA,
Larry
FIRST and FOREMOST.... teflon ONLY works on TAPERED threads. If it
isn't a tapered thread.... forget the teflon (or any other sealant..
fix what is wrong).

There are different formulations of "teflon" for different
applications. For fuel, a "non-white" tape is probably called for.
Don't use the wrong kind. Not all tapes are created equal.

Don't put ANY tape on the first 1-2 threads.

There are semi-liquid thread sealants that are better than the tape.
Globs of pipe dope don't seal better; don't put pipe dope on the first
1-2 threads.





I might be wrong but aren't you supposed to use double flared on metal
fittings? I don't think compression or pipe thread is allowed.
The original Yamaha fittings weren't flared. They also didn't seem to
have any Teflon tape or any other pipe dope on them.

Gene wrote:
On Wed, 02 Mar 2011 19:25:54 -0500, wrote:


On 3/2/2011 5:41 PM, Gene wrote:

On Tue, 01 Mar 2011 19:59:01 -0500, L wrote:


Google results show differing opinions. Has anyone used Teflon tape
without success on a fuel line thread?

TIA,
Larry

FIRST and FOREMOST.... teflon ONLY works on TAPERED threads. If it
isn't a tapered thread.... forget the teflon (or any other sealant..
fix what is wrong).

There are different formulations of "teflon" for different
applications. For fuel, a "non-white" tape is probably called for.
Don't use the wrong kind. Not all tapes are created equal.

Don't put ANY tape on the first 1-2 threads.

There are semi-liquid thread sealants that are better than the tape.
Globs of pipe dope don't seal better; don't put pipe dope on the first
1-2 threads.






I might be wrong but aren't you supposed to use double flared on metal
fittings? I don't think compression or pipe thread is allowed.

You will see a lot of tapered pipe threads, AN flares, and SAE
flares.... maybe even a bubble flare!

No compression fittings, but if high pressure (fuel injection), maybe
a double flare...






It is an EFI motor. The fittings are on the fuel/water separator.

wrote:
On Wed, 02 Mar 2011 19:39:29 -0500, Gene
wrote:


On Wed, 02 Mar 2011 19:25:54 -0500, wrote:


On 3/2/2011 5:41 PM, Gene wrote:

On Tue, 01 Mar 2011 19:59:01 -0500, L wrote:


Google results show differing opinions. Has anyone used Teflon tape
without success on a fuel line thread?

TIA,
Larry

FIRST and FOREMOST.... teflon ONLY works on TAPERED threads. If it
isn't a tapered thread.... forget the teflon (or any other sealant..
fix what is wrong).

There are different formulations of "teflon" for different
applications. For fuel, a "non-white" tape is probably called for.
Don't use the wrong kind. Not all tapes are created equal.

Don't put ANY tape on the first 1-2 threads.

There are semi-liquid thread sealants that are better than the tape.
Globs of pipe dope don't seal better; don't put pipe dope on the first
1-2 threads.






I might be wrong but aren't you supposed to use double flared on metal
fittings? I don't think compression or pipe thread is allowed.

You will see a lot of tapered pipe threads, AN flares, and SAE
flares.... maybe even a bubble flare!

No compression fittings, but if high pressure (fuel injection), maybe
a double flare...

Where I have the threaded fittings are hose barbs into the tank and on
the water separator.

I have the barbs on the fuel line side. It's the separator I was asking
about. Even the two plugs for a two-engine system aren't flared.

wrote:
On Thu, 03 Mar 2011 20:18:45 -0500, L wrote:


Gene wrote:

On Wed, 02 Mar 2011 19:25:54 -0500, wrote:



On 3/2/2011 5:41 PM, Gene wrote:


On Tue, 01 Mar 2011 19:59:01 -0500, L wrote:



Google results show differing opinions. Has anyone used Teflon tape
without success on a fuel line thread?

TIA,
Larry


FIRST and FOREMOST.... teflon ONLY works on TAPERED threads. If it
isn't a tapered thread.... forget the teflon (or any other sealant..
fix what is wrong).

There are different formulations of "teflon" for different
applications. For fuel, a "non-white" tape is probably called for.
Don't use the wrong kind. Not all tapes are created equal.

Don't put ANY tape on the first 1-2 threads.

There are semi-liquid thread sealants that are better than the tape.
Globs of pipe dope don't seal better; don't put pipe dope on the first
1-2 threads.







I might be wrong but aren't you supposed to use double flared on metal
fittings? I don't think compression or pipe thread is allowed.


You will see a lot of tapered pipe threads, AN flares, and SAE
flares.... maybe even a bubble flare!

No compression fittings, but if high pressure (fuel injection), maybe
a double flare...







It is an EFI motor. The fittings are on the fuel/water separator.


Funny thing, I was just in one of those a couple weeks ago (bad pump).
Mercury uses some kind of red dope on the fittings.
There is still one more filter before you get to the injectors on a
Merc. It is after all of the threaded fittings. They use snap n locks
with O rings down stream of the fuel cooler.

That motor does have another filter under the cowling. I'm going to
change that next but this will be the first time. It's still fairly new.