1HDT fuel hose question

[Jan-78FJ40]

What is the size of the fuel hose that is in between the hard lines (from the tank) to the fuel filter assembly on a 1HD-T?
I have a non metric hose there and it fits poorly.
Inner diameter or part number would be very much appreciated.

thanks everyone!
Jan

 

[girraffe]

12mm or 1/2 inch ID

 

[Jan-78FJ40]

12mm or 1/2 inch ID

That was fast, thank you!
Jan

 

[rick_d]

1/2" = 12.7mm by the way.

some supply lines were 10mm early on so electric pusher pumps are used.

 

[mudgudgeon]

I found 1/2 was a poor fit, ended up using 12mm

 

[girraffe]

I found 1/2 was a poor fit, ended up using 12mm

I would have preferred 12mm but 1/2 was readily available. So I just used that with clamps

 

[Dave 2000]

1/2" = 12.7mm by the way.

some supply lines were 10mm early on so electric pusher pumps are used.

Some people are so picky! By the way, you did not use a capital S when starting a new sentence.

regards

Dave

 

[Bisonthecruiser]

Sorry to revise an old thread, but figured for historic use it may help to have more info in here. What size is the fuel hose running pre and post fuel filter for the 1HDT? I want to hook up a vacuum gauge post-filter, but am unsure if a 1/4 NPT fitting would restrict flow too much coming off from the t. Thoughts?

 

[Douglas S]

As mentioned above it was 10mm (3/8") on early trucks and 12mm (1/2") on later trucks.

 

[gnarlynick2072]

I just did my fuel hoses and used 7/16" which was a very nice fit on the barbed ends on the fuel filter. 11.1mm. close enough.

 

[Bisonthecruiser]

Thanks gents. So I'd be better off going with a different size gauge then from the sound of it . Going to hook up a dahl or racor to replace the factory setup.

 

[Bisonthecruiser]

I can't find a filter (racor/dahl) with greater than a 3/8 outlet (even 90gph). Please bear with me , but why the heck are they using 1/2 hose. 3/8 is sufficient for a 5.9 Cummins or 650hp Chevy, so what am I missing ?

 

[mudgudgeon]

Toyota changed to 12mm hose and hard lines early in the 80series (92 or 93) to eliminate surging at highway speeds.
Injector lines were also increased in size. Many early 80series trucks had these upgraded as a warranty item during routine servicing.

 

[toadshade]

Sorry to revive a really old thread, but I am replacing my fuel filter housing due to an air leak. If my engine originally had 10mm lines, was the barb fitting modified or sufficient to take the new 12mm line you refer to? I am assuming the new filter housing would be the 12mm. I don't want to fix one air leak with a new one in a different place.

 

[Bisonthecruiser]

You should be fine. Go to a racor unit

 

[toadshade]

I was checking these out during the thread but I need to do more research. Right now I need to get myself running so I decided the quick OEM was a safe bet. But so far I like the idea. Especially the finer filtration

 

[oldandintheway]

What is the size of the fuel hose that is in between the hard lines (from the tank) to the fuel filter assembly on a 1HD-T?
I have a non metric hose there and it fits poorly.
Inner diameter or part number would be very much appreciated.

thanks everyone!
Jan

Just did mine on our 1990 HDJ81 and they were 12mm - Used some 300psi rated diesel hose off amazon. Anything was better than the cracking decade old hose from ATEB. Peace