pulsation dampner screw
 

Yeah.. Took my primary fuel rail off.. The screw is in the cap.. Can I just screw it in and pretend that everything is okay?

-Tesla

Not an informed answer...........when I first overhauled my car, and knew not what that screw was all about, I just put it back in with locktite and pressed on with life. Since then I find that this device can, and does cause fires if it fails(not the screw, the damper). Still its been a few years now with no problems(in that area anyway). So, I say screw it. Have fun, and carry a on board fire extinguisher if you own a rx.

I had the same problem. After re-installing it, I still had a gas leak coming down the side of the motor, a little too close to the exhaust and turbo for me.

Bought a new pulsation damper, read about too many engine fires....

Greg O.

if the screws out it's probably too late. I wouldn't risk it. replace it

The screw is out, but it didn't seem to be leaking.... :-/

-Tesla

the screw has nothing to do with the leaking. it can leak with the screw in or out. what the screw does is hold the rubber in place from moving around too much. what happens is when the screw losens or comes out. the rubber moves around too much and springs a leak. so right now your rubber will be damaged a bit. it just might not be all the way through. so by putting the screw back in, it might last forever. or it still might rip the rest of the way. you won't know unless you try. but it's not worth chancing. many many people have had fires.

Bleh..

What was the final verdict about the 89+ fuel rails fitting on 86-88's?

Or.. What bad things would happen if i simply plugged the end of the fuel rail.. Like, removed the dampner, and just plugged it instead.

-Tesla

I'm not sure on the newer rails. I think some people have blocked it off but they did put it there for a reason. even some newer cars still use one. I think it puts more wear on the fuel pump and injecters without it.

I've read from reliable sources that the fuel rails are interchangeable. The 89+ has an advantage because the pulsation damper is integral and doesn't have the screw problem.

I discovered my screw was out while removing the injectors. It was replaced right away because 1) it's a pain in the ass to replace the damper later when it does fail (which it will). 2) I don't want my engine to catch on fire.

Check out http://home.earthlink.net/~burntoast...iondamper.html
for more info.

Lars

Here is the Mazdatrix read on the pulsation damper http://www.mazdatrix.com/c-pulsation.htm by the way, two of my three cars had fires from the previous owners. The turbo was a salvage vehicle due to an engine fire. Make sure you have new or better fuel lines installed under the manifold when you do work under there. Not a lot of hose and cost involved. Make sure you get fuel injection line also instead of regular fuel line.

Get rid of the 86-88 PD
 

I've got an 88 vert. The PD started to leak so I shut the car off until I could effectuate the repair.
Do not put the screw back in or glue it. The previous posts about the rubber diaphragm were dead on!!!
Ted Kosecki has said numerous times that this is a really bad thing to do. You are begging for an engine fire! Kudos to Ted for reiterating this forcefully and often!!
Replace the 86-88 PD/Primary rail with a rail from the 89-91. It fits without any problem. Just take the two screws from the 89-91 or find a shorter screw for the rear attachment point as the 86-88 rear screw is longer. Take a look at the old PD, it has a raised attachment point. That's it. If you replace with an 86-88, you are begging for a repeat in however long it takes for the new one to degrade.
By the way, from pictures, it seems the 89-91 is placed backwards on those year cars (with the "hat" facing the firewall). I placed mine in the same orientation as the 86-88 rails, with the "hat" facing forward. I asked and was told it makes no difference!
I found my 89-91 PD in a salvage yard. Installation is just like the old one, but watch the oil injection lines. They are brittle. I broke one of mine and ended up replacing all of them (don't forget the copper washers if you have to do this, not reuseable!)
Ralf

I had this problem... caused a fire. I was lucky- it only cost me $500 to fix it. (because the INSURANCE paid the other $2000!!!!)

FIX IT NOW! DO NOT just screw in the screw- replace the PD with a new one.

Brad

Once the screw backs out, time to replace the PD
 

The above comment is worth noting! I came up with the idea of putting the screw back in just a bit snug, then covering it up with J-B Weld! WRONG!
I just discovered that the screw and o-ring move in and out of the housing while the diaphragm moves. Keeping it from moving will prevent the damping from taking place. I guess this would be an easy way to prevent a fuel leak on a N/A engine.

This was posted in another FPD thread but just replace it with the one below.

Herko Fuel Pressure Damper PR4188 for S4 N/A cars

Fix it, it is not worth losing the entire car over a worn out part that is known to leak and cause fires.