Fuel Pulsation Dampener, unlucky or is there something else going on?

[89gte]

My fuel dampener is currently leaking from the top where it looks like it has been crimped against itself (metal on metal) from Toyota. I bought 2 more off of SM, but I found that these two leaked from the top as well. I have a third one on the way that should be here soon, and then I will give that one a go. I've read almost every thread archived on SM and a lot of Google on these things, and the information I've gotten from reading makes me think I have just been unlucky. I just can't believe all three of the fuel dampeners I have tried all leak in the same spot.

I would rather not bypass it. Toyota put it there for a reason, and I have heard that some develop an untunable lean condition at certain RPMS. I just wanted to know if anybody thought something else could be causing this. I have also installed new crush washers from Toyota. Could I be breaking it when I'm tightening it? Is there anyway my FPR could be defective, and creating too much pressure causing it to start leaking from the top (I would think it would be able to stand maximum stock pressure). I have screws on all of the ones I've tried, and I have not adjusted them from how I got them. One of them was from Turbo Habenero's 7M, which I know was running until recently.

Background information: It started leaking on the first startup after putting engine back together, I have RC 550s, Walboro fuel pump, stock FPR.

 

[toyotanos]

Nope, sounds like a failed diaphragm in the damper. It happens from time to time, and all you can do is replace it. It's unlikely anything you did caused it to fail, unless you stuck pins and needles into it

edit: have you bypassed the J-tube? That could cause too much fuel pressure, but not so much it blows out the diaphragm I would think

 

[89gte]

I have not bypassed the J-tube. I just must be unlucky with these things. Hopefully, the next one will hold. It sucks having to wait to drive the car because of a small defective part. It's so easy to change too.

 

[toyotanos]

Since you're running an upgraded pump, I would suggest either drilling out or bypassing the J-tube. It may be a contributing factor to the failure you have been experienced, albeit slight.

I hear ya on the small things killing the car- you'll survive though. I know I have!

 

[jonahs_supra]

i sold him 1 of the dampners off my 87
it sat on the shelf for about 1 yr before he bought it
before installing my aeromotive a1000 afpr i was using walbro 255 with stock fuel system with no problems

89gte if that dampner is for sure bad let me know and i will gladly refund your money

sorry for the delay and i hope you get it fixed

 

[89gte]

Jonah,

It's no problem. You couldn't have known, and you gave it to me so cheap it was pretty much just cost of shipping. I'm going to try one more, and then go to Toyota. These little things are pretty expensive new.

 

[hvyman]

If your running a bigger pump definiality drill out or bypass the j tube. It acts as a back up for the fpr incase it fails. Bigger pump will out flow that tiny litle hole it has.

 

[jetjock]

If one thinks about it one will come to realize some parts should not be bought used.

 

[89gte]

I understand that buying used parts comes with the risk that they may not work; however, I have read (on this forum) that this particular fuel dampener rarely goes out. My Toyota dealership sells the fuel dampener at $122. When possible, I would prefer to save money as long as I am not sacrificing performance. If it is functioning properly, it is still an OEM part. However, I agree with you JetJock that purchasing new parts would be the best course of action.

 

[jetjock]

Appears you missed the point: some used parts come with a much higher risk of not working, or not lasting, than others.

 

[Nick M]

My 21 year old dampener started leaking. So I bought a new one. Too easy.

 

[jetjock]

Meh, you could have bought three bad used ones. So much cheaper and easier. After all devices with diaphragms, especially those with high cyclic rates, last forever...