http://www.rotaryresurrection.com/

look under tech and find the fuel pulsation dampner...
its got the pictures, banjo bolt size and everything you need to know about doing the mod

 

You may have, but I'm betting that few other people have...

I'd also be far more worried about the 20 year old hoses and belts, as well as the hacked up wiring I find on most FCs then the PD failing.

Or the 20 year old brake lines, old bearings, oil cooler lines about to burst, etc.

 

stop,stop!!!

i keep replacing and replacing and think im almost done!!
then YOU come along and do this!!...DAMN YOU!


im half way done with that stuff anyways....i dont think ill ever be done though...

 

thats why i got bored and went through my entire chassis and engine harness and removed all used wires, cleans connections, and reloom everything. i do mean everything. i have too much free time. then again it helped to have the car be sorta of a purpose built car so about two 55 gal trash cans of wiring crap came out.

personally i replace the Banjo bolt on all of my sevens without issues. Then again, i replaced everything.

The theory is similiar to why you have (err..should have) a water hammer arrester in your house plumbing. when you turn on the faucet water flows, when you turn it off, the pressure comes to an immediate hault which causes a shuttering action, usually quire audieble. Same idea only smaller and more often.

 

I'm going withthe banjo bolt. And I agree with you on replacing all the other stuff. 20 years old is a long hit in that hot engine compartment!

I did find one problem area everyone should take note of. The wiring loom comes alfully close to sitting on some hot parts. In my case it was on the hose of the air pump right where it attaches. I started unwrapping it and found it had almost melted into one big *** wire! That's where I had my TPS problem. Now messure the distance from that spot to the PD.... inches. Thank GOD it didn't blow up!

I caught my leak on the 1st tank of gas when milage went from 300 to 200. That's 5 gallons of gas that PD was squirting out onto the top of the engine while I was tinkering with the wiring problem!

That's a hell of alot of gas to be sure! Why it didn't blow up in my face is just luck of the draw. So i'm pulling the Dynamic chamber and replacing everything under there and ditching the PD for a banjo bolt. I'd love to get rid of the rats nest but no need to go where I know nothing and have no problems... yet.

Off I go. Thanks everyone.

 

I think this ought to be the 1ST FIX ANYONE DOES TO ONE OF THESE CARS NOW THAT i KNOW WHAT IT CAN DO!

 

Alright, I was about to do the PD mod, but problems. First, I have a friend who had a fuel rail lying around, so I grabbed a banjo bolt off of there. However, it's not the right size, and it won't thread into where the PD used to be. The fuel rail is off of a second gen TII, I don't know if it's a S4 or S5. My car is a S4 N/A. Did they change the size of the fittings for S5's or Turbos? Also, I was looking at the pictures on Rotary Resurrection, and I would think they would have had the same problem because the threaded part of the banjo bolt in the pic looks bigger than the threaded part of the PD as well. Am I missing something?

 

I went down to NAPA and bought two M12 X 1 1/2" banjo bolts for 8 bucks. I had my alternator off and realized I could probably twist the old one off the fuel rail without having to dismantel the top of the engine. It wouldn't move so I'm waiting until the WD 40 sinks in and maybe able to twist it off. The palstic cover came right off too easily.

I don't know about the different sizes but I'd guess the turbo is different probably bigger.

 

I had to do this mod. it sucked because I had to take off the upper intake so I could pull the injectors and switch them out for the secondaries, since they were in better condition. I have yet to get my banjo bolt from summit and see if it will work, its the earl's 12x 1.25. it must take them for ever to get there shipments in order because I ordered the thing 10 days ago. but while I had the upper intake off I cleaned it up a bit to make it look better and get rid of all that dirt that the gas left behind

 

NAPA always has those parts that arent easy to find at local shops or stores...they might be a little more pricey here than autozone or advanced but when i walk in and ask for something they head right for the back (to get the part) and the people at autozone stair at the books and sratch their heads...LOL

 

You got that banjo bolt from NAPA!? You're lucky, they didn't have anything bigger than 10mm when I looked. The Mazda dealership couldn't get one either. I went with the Summit one and it's been working fine for over a year. Don't re-use the factory crush washer, whatever you do. If you need some help with it, PM me. I've been through it and I'd be happy to lend a wrench.

 

I agree. If you ask me, ANYTHING rubber on the exterior of the car should be replaced. Well, maybe not some of the grommets such as those on the firewall... but you know what I mean.

Welcome to owning a 20 year old car. Hell, can't I register my car as an antique in 5 years?


Wow, you got lucky.

 

If you want to know when a new PD will "go bad", just look at the original one. It'll go bad in 15+ years time just like every other one. More likely it'll outlast the car. Whatever excuse you use for removing the PD, you need to come up with a better one than this.

 

That's one of the reasons I check my mileage on every fill-up.

There also exists the Marren PD, which does not leak gasoline onto the engine when it fails.

 

My excuse, other than peaceof mind, is that I don't have excess money to spend. I can barely afford rent, tuition... etc.

 

Mines went bad in 1996.
That's just about 10 years on my 1987 model.
That's not even close to "outlasting the car".

I think I'm kinda jaded cause luckily a friend was behind me when my FC caught on fire.
I could've ended up DEAD from the car catching on fire if I wasn't flagged down.
Something to think about...


-Ted

 

That's what I'm talking about. Why live with that possibility when you can banjo bolt it.

Not burning up > death.

 

Ten years is well below normal life expectancy. You just got unlucky. Mines still fine after 18 years and judging from the regular threads about this there are still lots of original (15-20yo) PD's still out there.

I never said an original one would outlast the car, I said a new one would.

Jeez, talk about over-dramatic. You would've kept driving even with smoke and flames pouring out from under the hood? I'm pretty sure you would've figured it out long before you were in any real danger.

 

So are you implying the original PD is not new?


I never knew the car was on fire.
The flames were UNDER the car.
My friend saw it cause he was behind me.

I give you props if you could stay calm if you did figure out your car was on fire.
I just don't want to take the chance anymore.
Once was one time too many...

If I were to do it "right", I'm going with the SX Engineering FPR and gut all that stock crap.


-Ted

 

As much as I'm sure everyone loves reading another banjo bolt debate, there is a topic in the archives for a reason. I think it is safe to say that all this has been well covered before.

 

For anyone worried about any POSSIBLE ill effects from PD removal.....

In 1987 Jeep introduced the MPFI 4.0 L I6. Other than emissions and ECU changes these engines remained very much the same till 1999. The only part used to regulate and control the flow of fuel was a simple vacuum operated pressure regulator mounted to a single fuel rail for all six injectors. There was never a pulsation dampner, and these motors are known for running for 200k plus miles with minimal part replacement.

I recently sold a 88 Comanche that was still running well on the stock injectors with 230k miles on the odometer. Fuel pulsation caused by the opening and closing of the injectors is very minimal, and the risk of a failing injector due to this is considerably lower than the risk of a failed PD causing a fire.

If a Jeep can run for close to 20 years on the stock injectors, with all six creating pulsations in one rail, why can't a RX run for just as long with only two injectors per rail creating pulsations. Ditch the PD and run a banjo. IF an injector fails, get a new one. No big deal.

 

I agree. DSMs never came with pulsation dampeners, and we've (the DSM crowd) never had problems with injectors. Although technically, the stock FPR uses a diaphragm and is itself dampening.

 

I just found another source for banjo bolt for this mod. Russel, the makers of stainless steel hoses and such, offers a M12 x 1.25 banjo with a 1/8th" NPT port in the head. This port can either be capped off or used for access for a fuel pressure gauge or a wet nitrous fuel feed (I think). I ordered one today, and when it comes in I will post a pic and part number.

Any Autozone should be able to get this part. The price is $9.99 (US).

 

quick question... before I hammer away at the PD (too late really) is there anything I need to worry about breaking? I'm trying to remove it from the front now that the alternator is out of the way. I'm down to the "frame" of the PD but need to cut more of it away before I can get a wrench on the nut. I think I can do it. I haven't been able to get the unit to turn so far while pounding away at the outer rim.

 

I here is a link to the page on Russell's site for the banjo bolt.

M12 x 1.25 Banjo Bolt