Read this before changing dulsation dampener or installing PD elimination banjo bolt..

So I had the usual pulsation dampener leak start at 163K miles on the 86 NA. I bought a new one from rx7world, and went to work. Put in new one, put everything back together, ran fuel pump, and there is a fuel leak near the PD.

Well, you can't see anything with the manifold on, so I thought I'd take the manifold off, and run a temporary fuel line where the top fuel rail would normally be, so I could pressurize lines without manifold and see leak. I did this and there was no leak, so I thought maybe the new PD copper washers flowed into place and the leak stopped due to waiting a day. I put the manifold back on along with everything else, pressurized the fuel system and the leak is back.

Next I made extra long fuel line pigtails for the two lines going to the manifold along with adding a fuel pressure gauge to the system, so I could take manifold off and on without removing fuel lines. I pressurized the system with the manifold sitting on the fender. No leak. I put manifold on and it leaked.

This is when I figured out the problem. The manifold intake runners are extremely close to the PD. In fact the under side of the most forward runner has a depression in it to clear the PD. It's so close that if the factory fuel line hose clamp has its tangs pointing up(the one that comes off of the PD banjo), the intake runners will push on it and cause the line to compress on the top and gap at the bottom. This gap at the bottom was the cause of the leak and the reason I had to take the manifold off-on 4 times!

Make sure you orient the clamp tangs down or to the side. This was a very frustrating job. If you used the PD elimination bolt, you would have the same potental problem, althought you might be able to see it a little better.

 

Sorta had the same problem but I got rid of the 24 year old clamps and used new hose clamps.

 

Damper, not dampener. Lol, sorry pet peeve.

 

 

just use new hose clamp, problems solved. (who in their right mind would reuse the old one anyway?)

 

The OE spring clamps continue to tighten on their own as the rubber of the fuel lines ages and shrinks.

A worm gear/screw type clamp will not do that.

 

I always use new clamps (my other cars) and never had any problem.

just my experience that's all.

 

Fuel injection clamps are better to use than the worm gear type clamps.You get more grip of the hose.
They may cost a bit more,but it's the Piece of mind knowing that you don;t have to worry about any leakage or lines popping off!

 

this is an S4 t2? ive done that too, the ANGLE of the hose fitting is IMPORTANT on these. you can get it so that the manifold pushes down on the hose fitting and UNSCREWS the PD!

so yeah ive seen this too! but its always been way worse.

the S5 fuel rail is a good fix, cause you can't have this problem

oh yeah worm type hose clamps suck, and should be thrown away

 

my banjo bolt fixed it first try, tho it was a bitch to get threaded

 

I think many of you are missing the point. The type of clamp is not important. I did put new hoses and clamps on after I found the leak, but if I had put the new clamp on with the screw on top, it would have caused the same problems. There is no clearnace for tangs, screws, etc between the fuel line and the front intake runner. I don't want anyone else to waste all the time I did.

j9fd3s is right about the angle. The banjo joint must be kept at the lowest angle possible. There is a tab to position it. This car is a NA, but I believe the TII has the exact same setup.

Banjo bolt vs. PD makes no difference the problem exists for both.

 

oh really? i didn't know you could do that on an S4 na! i guess its been a while since i had one apart.