New to me 1985 XJ6 that has had the fuel system replaced prior to my buying the car, including rebuilt injectors and all new fuel lines and clamps.

I am fighting a leaking injector hoses on #5 and #6 where it comes off the fuel rail. When I got the car not a single clamp was tightened, so I am not all that confident the correct size hose was used when the injectors were replaced. My question is, what is the correct size hose? I have read OEM is 7.5mm, but 7mm will work and Moss motors list it being 8mm. I have also read where 3/8" and 5/16" was used. I will inspect the fuel rail for any nicks from when the old hose was removed, but am leaning towards the hose being the issue. And I assume these are ID measurements.

OEM hose clamp part number is EAC3215/2 comes up as part JHC200101 on SNG Barratt and is a worm style clamp at $5.50 each and is listed as fitting 3/8" - 1/2" OD hose. Most other sites show the traditional injection style clamps.

Advice sought. The most important is buying the correct hose that will not leak.

 

I have a new spare section that I believe to he 5/16", but I am away until next year when I can check it.

 

Hello, Don't use a worm clamp, Find a full circle clamp that tightens evenly around the hose. A worm clamp will tighten unevenly around the hose and possibly cut it.

Thank you.

Larry Louton

 

I did some measuring, and it makes sense that the OEM size is 7.5mm. 5/16" is 7.9mm which would go over the large section fine, but then you are asking a clamp to take up .9mm of slack on the narrow section. Maybe this is all well and good and would work, but 7.5mm hose is what I am going with. I had a spare fuel rail that still had the original hoses on it and the part that slips onto the injector measured 7.7mm ID and that is a little stretched from being on the injector for years.

Continental 916030000527, 1149971882EC5 Fuel Hose/Line; Unbraided, Internally Reinforced; 7.5mm ID; Bulk - Mercedes | 1149971882 11499718821 2304768726 FHM7.5X3 (autohausaz.com)

• Continental 1149971882EC5 smooth rubber fuel hose
• 7.5x13.5mm internal string reinforced electronic fuel injection rated bulk fuel hose

 

The factory used worm clamps and that is what I went with. I feel the key to any clamp, especially worm clamps, is to buy good ones and not cheap made in China ones. If you look closely at the factory worm clamps you can see they are made much better than what you would get at some auto parts box store. The Comp Cams description sounds like they are the same design as the factory clamps. I guess time will tell.

I bought a box of 25 Comp Cams clamps off Jegs.

COMP Cams G3912-25: HOSE CLAMPS 12-20 MM 1/2-7/8 - JEGS

Gator Brand Clamps are made using a stainless-steel continuous band with extruded, asymmetrical threads for reliable performance. The edges of the band are rolled to prevent any sharp edges from damaging the hose. This is especially important on silicone hoses that have a soft, vulnerable cover.

An asymmetrical (offset) gear box is employed to reduce clamp twist when tightening. The gear box housing is designed to remain stationary as the clamp tightened to prevent movement over those hose. The combination of the asymmetrical gear box and the extruded threads provides an even clamping force over the surface of the hose that ensures proper sealing with minimal torque. Gator Brand Clamps hold up under 3.7ft./lbs. (5mm) torque; conventional clamps strip and fail at this torque.

Gator Brand Clamps can be installed using a flat blade screwdriver, metric socket wrench, or with the Gator Brand Flexible Clamp Tool for maximum torque potential.

 

7.5mm hose fit much better than 5/16" or 8mm and the Comp Cams hose clamps took a lot more torque. No more fuel leaks.