R.P.M.

iTrader: (3)

Hey, I found a thread a long while ago with a Mitsubishi part number for a banjo bolt that replaces the Pulsation Dampener in the primary fuel rail.
I bought a couple from the Mitsu dealer and they worked great, they were the right thread, right length, right diameter. Only cost $10 with new copper washers.

I just cant find any receipts for them and I dont know the part number. I have another S4 N/A with a leaking pulsation dampener, so I'm going to replace it with the Mitsu Banjo bolt.

If anyone can find the thread or knows the part number off hand and could let me know, it'd be greatly appreciated!

Thanks
Joe

R.P.M.

iTrader: (3)

Well I went down to the Mitsu dealer and looked around in their stock room and found the bolt and copper washers needed.

Banjo bolt part number is #MS650013
Copper washers #MF66064

More expensive than I thought....total was $23.50

RotorRex

iTrader: (2)

So does this work? any downside to doing away with the dampener? I just need to get this thing running. Mazda wanted $175 for a new dampener. ouch.

Trots*88TII-AE*

iTrader: (11)

That is a long outstanding debate, I`d search it instead to avoid an onslaught of verbal diarrhea.

kustomizingkid

iTrader: (2)

I've never seen an adverse affect from it....

Icemark

Many people with blown motors may not attribute a missing PD with a fuel issue.

The debate is that some people claim there is not an issue replacing it with a banjo bolt. The draw back is that it forces the soft fuel lines and the Fuel pressure regulator to act as the PD.

Thus, there may be specific RPMs where you may have a harmonic in the fuel rail that does not have the PD and that harmonic could cause a un-desired and uncontrolled lean or rich situation.

No one has been able to prove one way or the other adverse effects, but based on fluid dynamics there will be adverse effects if there is not a PD; regardless of how many people say there is not on their car.

kustomizingkid

iTrader: (2)

Do you have any concrete factual evidence of a pulsation dampener causing an actual engine failure?

Agent_D

iTrader: (2)

Engine fire vs possible changes in AFR's, makes the decision an easy one imo. Unless there is a drastic change in the AFR's, which is more worrisome for the TII owners, its not really a big deal. Could always get an S5 primary rail too.

Icemark

I guess you had trouble reading so I will repeat it:

But having a functioning PD reduces the possibility of an uncontrolled A/F ratio as well as reduces the strain on the fuel lines (which I have seen fuel lines leak- interesting enough only in two cars without PDs, and a banjo bolt instead).

Icemark

and put your engine's life in the hands of a rubber stopper... I think not.

S5 and S6 rails leak just as much as S3 and S4 rails do, if not more.

kustomizingkid

iTrader: (2)

You know what there is some documented proof of?

RX7's being destroyed by fires started from a leaking pulsation dampener.....

2slow4stock

iTrader: (18)

Yes, my friends car caught fire acouple days ago because of a failed pd... Leaked and fire.. So proof. Want proof drive a s4 with a leaking pd and when a fire comes from underneath the hood you can say "Nope wasn't the pulsation dampener that caused this"

Agent_D

iTrader: (2)

Maybe I've been lucky then, I have never had a single S5 PD leak on me. But every single S4 PD I've had has leaked uncontrollably, until I got sick of it and JB welded the entire end of that PD while I searched for an S5.

Also, I have never seen a thread in the 9 or 10 years I've been on the forum saying "I had an engine fire from an S5 PD leak." I don't browse every single day or every single thread, but I've yet to see a thread that starts with such.

You're the last person I would contradict mark cause you are the person I would normally ask for anything, so don't think I'm trying to say you're wrong, just that I've not seen it.

So again it comes down to, would you prefer an engine fire or possibly some weird AFR's, whatever fuel rail you have. If there is a proper fix for the S4 PD that will allow it to never have a leaking problem then that would be great, but as far as I am aware there is not.

slick_ep

ok, so lets weigh this up,,,, who here has seen blown fuel lines in a rx7? compared to who has seen a fire in a rx7 due to pd. reply with fire or lines

lastly do japspec s4 rx7 svannah have a pd?

Fijensen

I bought a car for 200 bucks that had a PD leak. The engine had just been rebuilt by rotary perfomance in Plano, Tx. The owner probably opted not to have it changed. He spent $2600, and ended up with a glob of molten plastic covering a nicely rebuilt block. I cleaned it up, and have been driving with it in my car for 2 years. 115 psi both rotors, and I got my 200 back selling parts on Ebay. Yeehaw

Turbo7MN

Kid phrased that question poorly... he was referring to PD removal with the banjo bolt. It's very common knowledge that a leaky PD can and will cause engine bay fires.

Icemark

There was one here 6 months ago, and the S6 PD uses the same design, so you should check out the engine fires caused by PD on the FD section of the board.

This is how the S5 and S6 ones work:



JB welding it is just about the worst thing you can do.


They tend to leak at the fuel rails, when they go... I guess it could be attributed to the owner being an idiot and over or undertightened the fuel line onto the fuel rail. Funnny how it seems much more common through on the ones with Banjo bolts. Of course many of the owners have not worked on FC's since they were new as I have, so they may not see issues in the short time they have had their car.

All fuel injected cars have PDs from the factory. On the S4 Jspecs they are on the upper fuel rail, at the back of the motor. A spot considerably better as far as heat is concerned over the North American spec cars where it is on the primary rail.

Let me ask the non believer's (who for some reason think this is something to argue over), why do manufactures put a PD on every fuel injected car from the factory? Don't you think that if the manufacture could get away with a 50 cent bolt instead of a $75 pulsation Dampener they would?? Especially on the S5 model which had some many short cuts and cots cuts it's not even in the same ball park as a S4. So why didn't they use a bolt? I guess so you car can burn down after 20 years of neglect when one fails (or 10 years on a S6). Could it be that they are needed to stop the hammer effect of the harmonic. You can duplicate this same effect in your own home by turning a faucet all the way on, then closing it as fast as you can. You will hear a nice Bang to the pipe when you do this. This is the same thing that happens in the fuel rail, with only the FPR, PD and rubber fuel lines to absorb. If our lines were solid copper or brass, it might not be a concern (other than of course for how the injectors have to deal with it.

So, you can use a bolt, if you want... I personally will never- there are enough tuning issues when you build up one of these motors, and I don't want to band aid anything, or you can use a PD. $150 for a new PD that should last for the next 10 years or 100,000 miles is hardly a cost that can even be considered and one less thing to worry about.

Now if you are an idiot and have not changed the PD at 100,000 miles or 10 years, then your lack of maintenance is the issue, when one leaks, not a old worn out part.

Agent_D

iTrader: (2)

So have you or anyone you know actually purchased a brand new PD and not had any problems for years? I realize 20 years of wear is a lot, but how does a brand new one cut down on the screw working its way out and leaking on an S4 PD? Could loctite be used on that screw to keep it from working its way out? Or would the heat and fuel just break down the loctite?

Icemark

Yeah, actually I buy new PD's everytime I buy a FC. Even my 10thAE which I just rebuilt a Jspec motor for, I replaced the PD with a brand new one (even though in theory the Jspec one only has 45K miles on it and it is on the 2ndary rail away from a lot of the heat).

It is cheap insurance to just replace it and using the S4 fuel rails you can just unscrew and replace the PD and not have to replace the whole fuel rail.

There is loctite on the screw threads from the factory on new ones. Remember that screw needs to move up and down when it is attached to the plate inside, so that is why you don't want to glue them or cover them so that they can't move.

I think it is more the long term vibration that kills the loctite on the screw. Remember that screw is moving in and out every time an injector closes to help absorb the shock wave in the fuel rail.

But the screw is only half the story. It serves the same purpose as the rubber tab in the S5 PD diagram, that it keeps the membrane from over or under extending. So without the screw, the membrane can over/under extend and eventually rip. Of course putting the screw back in too far also does the same thing.

This is why I think the PD is important. Because all the movement in the rail. Sure there have been people (like Ted for example) that advocate the use of a banjo bolt (and have done so and ran cars with out PDs for years), but what is happening to all the movement that the PD normally helps absorb? What if it causes a low pressure moment at 4500 RPM because of the timing of the injectors closing... that low pressure suddenly could mean a lean condition. Most people wouldn't expect that to cause a blown motor... and I am not saying that it can result in one... there is just the possibility... a possibility that for spending $150 I am not willing to take.

RotorRex

iTrader: (2)

You called that one. Sorry all for resurrecting the debate

TitaniumTT

I don't understand why kids don't listen to people twice thier age with 10x the experience. Are you not getting enough attention at home?

Do a little research on fluid dynamics and maybe you'll understand why a PD is necessary. Here's a little expeiment to. Ever been in an old house and turn the water off and here the pipes shake? Now imagine doing that as many times as an injector does at fuel rail pressures and tell me that PD is useless.

You do realize that most new homes have a PD on things like washing machines and dishwashers right? In old homes if you have the shaking pipe problem the first thing you do is put a PD on whatever appliance/faucet is making the rattle and it goes away. Much easier than tearing a wall down

Stupid kids

87 t-66

iTrader: (133)

here is some good info on the subject

http://forum.teamfc3s.org/showthread.php?t=29559

kustomizingkid

iTrader: (2)

If it was so important why do cars with the PD removed still run fine? Why isn't a PD used on all cars if they are so important?

The comment about fuel line damage is really laughable, injector bounce is the only reasonable claim anyone can make, but that is a long stretch too. I have only seen injector bounce on one car and the injectors were close to being maxed out at WOT.... that problem was remedied by replacing the stock injectors with larger more appropriate sized units.

TitaniumTT

Let me re-iterate what Mark already said. Maybe in a manner that you will understand



































EVERY SINGLE PRODUCTION EFI CAR PRODUCED TODAY HAS A PD FROM THE FACTORY.


Cars that don't have PD's are owned by people that take them off becuase they don't have the intelligence of factory engineers.

Mutaku

It simple terms, yes your car will run without a PD, just like it would run without a lot of things. What it comes down to is this, the Pulsation dampener serves a purpose as stated above. Yes you could run it forever and not have a single issue, or you could end up blowing your motor because you ended up running lean or something similar. Some people will argue that the PD does nothing and some argue the opposite in the end its up to whether or not you want to believe in the R&D of the manufacturers or someone on a forum.
If you want to take that chance power to you, I'd prefer to have one myself because its that extra bit of reliability that you can get. Yeah sure it does break and end up leaking but thats why you should check your car daily (this applies to any car really).