So after my last post I was feeling pretty defeated but I spent some time in the garden which helped get my mind off the car and show for a while.
After getting a few tomatos and zuchinni planted it was time to think back on my morning issues to figure out what was going on.
I came across this video on YouTube which very clearly shows how these fuel pressure regulators are built and it struck me that if the diaphragm fails it should fail in the HIGH position, meaning the engine would be supplied with maximum pressure, not minimum. So a decrease in fuel pressure means there’s some type of leak occurring at the relief seal going back to the surge tank.
The only other component between the FPR and HP pump is a 40 micron filter. Since the pump and surge tank were newly installed I supposed it could be possible it brought along a bunch of contaminants with it, potentially clogging the filter.
It was easier to get to the FPR so I tackled that first – 4 bolts and you’ve got the guts of the FPR laid out, I didn’t even have to pull any lines. Unsurprisingly, the diaphgram was fully intact. There weren’t any indications of distress to the diaphgram or to the sealing surfaces at the relief. Based on how it’s designed, it’s highly unlikely the seal could have gotten off-kilter or offset enough to cause a leakage condition. These results didn’t jive with my previously observed issue, where I saw fuel pressure decaying rapidly when I had the check valve located on the INLET side of the FPR. Head scratching continues, but I don’t think this is the cause for my 20 psi reading.
I then pulled the filter – I had installed a new filter element prior to closing out the new setup – and I ran alcohol through it going in the reverse direction. Nothing washed out from the filter.
This wasn’t looking good for the HP pump …
I reassembled the filter case, this time leaving the filter element out, and re-plumbed the fuel system. With the filter completely eliminated the pressure loss across it should be minimal. Unfortunately pressure had fallen to somewhere south of 15 psi now.
To eliminate my fuel injectors and the FPR relief I disconnected the line going to the fuel rails and reconnected it to the FPR relief port; this effectively dead-heads the HP pump and takes the FPR relief out of the equation. I plugged the remaining port at the FiTech surge pump.
With the low pressure pump cycling to ensure the surge tank was completely full, the HP pump continued to be stuck in the mud, only making ~10-15 psi.
OK, there’s really nothing left to do but pull the FiTech surge tank for a deeper inspection. In the meantime SLC veteran AUzwiak had informed me that a FiTech surge tank used in a prior build of his had failed with similar symptoms – ~15 psi maximum discharge. When he opened the surge tank he found the line between the HP pump discharge and the surge tank outlet fitting had broken, which explains the pressure loss.
After removing the surge tank I attempted to crack it open but I quickly discovered that at least 1, possibly 2 screws retaining the upper cap were cross-threaded. There was no way to open the case without totally destroying that bolt (and potentially the tank).
The FiTech surge tank is going back to Jeg’s and I’m walking away from FiTech altogether. That’s 3 instances of failure due to poor quality (my 2 units and Allan’s). Given the extremely small sample size that’s a real statement about the quality of this product!
I thought really long and hard about what I should do next …
… and I decided to purchase ANOTHER Bosch 044 pump. Before everyone rolls their eyes and calls me crazy, let me explain (this will be long and circuitous):
My issues have stemmed from poor quality; either manufacturing (knock-offs) or assembly (FiTech). The only person I really trust when it comes to putting stuff together is myself. So why not build my own integrated surge tank? Note, this confidence ends at the mechanical bits as I can’t wire my way outside a paper bag.
That’s the line of thought I was going by anyway, and here’s what I found:
- There are several companies out there who manufacture great looking surge tanks, offered with and without pumps. I was able to find one company whose design I felt was superior to others, and was better than I could produce myself.
- I was messing around on Summit’s website and for giggles loaded my cart with the Bosch 044 pump. I clicked on shipping estimate and added my zip code – and it gave me a price! I called their bluff and went through with the ordering process – and I received a confirmation!
- It’s not cheap going this route.
Why did I buy another Bosch 044 pump? As strange as it may sound, it’s because it’s the only pump I can truly verify is GENUINE and not a knock-off. I guess the good thing about being the most popular pump to counterfeit is Bosch has implemented a verification process to let you know whether you have the real deal (I believe they do this for many of their products, not just pumps). If I were to purchase an integrated tank/pump system I wouldn’t be able to verify that the included pump was genuine … so I’m going to pay extra to ensure I get that verification code. As far as I know, no other pump manufacturer does this to ensure you’re not getting a knock-off.
Of the multiple surge tanks available that can accomodate the Bosch 044 pump, I felt the one designed by Radium Engineering was the best of the bunch. Unfortunately it’s also one of the priciest of the bunch coming in at ~$400 (ironically, you can source it for cheaper on eBay but I’m staying well away from eBay for this one!).
I was pretty set on staying with an in-tank pump/surge tank because it addresses all the major concerns I had with my prior design (heat, vibration, etc) and the noise suppression is now much more important to me after having listened to the FiTech.
The Radium unit also addresses one of the issues I had with the FiTech unit – cheap, hard to access binding posts. With all the hoses plumbed to the very small cap, it was nearly impossible to tighten the electrical posts due to access issues. The Radium unit has a Mil-Spec type connector that can be easily attached, even with the top of the can fully populated with hoses. It’s even offset to the side so you’re not having to squeeze your fingers in between 4 fittings. The Radium unit keeps the Bosch pump fully submerged and hard-mounted; there’s no clamped rubber hose routed between the pump discharge and the outlet.
So going with a Radium surge tank + Summit sourced Bosch 044 pump + me personally assembling the unit addresses every concern and issue I’ve encountered so far – let’s hope there aren’t any new ones!
How’s it possible that Summit’s willing to send me a Bosch 044? I have no idea. When I originally built my fuel system 2 years ago no one was willing to sell me a stand alone fuel pump (hence my going to eBay). But in the interim, for whatever reason, Summit has now decided they’re going to ship these pumps to CA residents. Amazon, however, still will not. I don’t know if legislation has changed, if Bosch has made a change so it’s now OK in CA, or if Summit decided they DGAF and they’re doing it anyway. Or I slipped in under some computer glitch. I’m taking getting my soup and I’m not asking any questions!
Assembly of the Radium surge tank is fairly straightforward.
**Update: yeah, so that rubber washer I made isn’t sealing well enough. I tested the system by cycling the pumps while the car was in the garage and things looked good, but once I hit the road for a short test drive it started leaking. Guess I’ve just got to hold my horsies back and wait for that washer to get here
I got all the wiring wrapped up at about 10PM and considered whether I should be a good neighbor and wait until the next day to do a test start … what the hell, they can only hate me for so long, right?
The engine cranked to life on the first attempt – WOO! Man, what a relief to finally get a handle on this fuel system. My fingers are crossed it’ll prove to be reliable, updates to come as they develop!
Generally, human aural memory is very short (your ability to remember sound). If you don’t hear 2 things back to back, it’s easy to forget which is louder – but subjectively, it seems to me like this Radium/Bosch combo is a bit louder than the FiTech was. It’s certainly much quieter than having the Bosch pump fully exposed, but I can definitely tell when the pumps are cycling, even in the cabin.
Whatevz, I’m over it.
I got a few blocks of driving in then I popped the rear cover to look for any leaks – and the cloud hanging over my head opened up and provided me with a nice puddle of fuel right on top of the Radium surge tank. Apparently that DIY rubber washer I installed wasn’t sufficient to keep the tank sealed. I turned around and nursed the car back home. Bummer, guess I have to wait for that $0.05 washer from Radium before I can get back into the saddle! When I called them and inquired about possible next-day shipping for the washer the shipping charge was going to be $70! I decided I’d let USPS do their thing and enjoy my soup.
Here’s a walk-through video of the Radium surge tank along with a few minutes of driving – the few times I’ve been able to get into the car these past few weeks has reminded me how much I enjoy driving the SLC. It’s really an incredible experience for the driving enthusiast! – YouTube link
The new washer arrived and I got on with the business of reinstalling the surge tank. After having done this for the fourth time, you find a certain rhythm and it goes surprisingly quick! I got everything buttoned up and cycled my pumps to pressure test the surge tank – all looked good in the garage (as it did last time). Since it was 10:30PM on a weekday I figured it would be a good idea to hold off on testing the new washer until tomorrow.
Good news – the new washer is holding up like a champ! A short drive and everything’s still leak-tight! Now to find some time to drive the car!