Help needed ASAP

[Jeff G 78]

Don't you hate ambiguous specs. I did a little digging and came away more confused than when I started. I don't know for sure what those numbers mean...:mad:

What are the part numbers for the pumps you bought?

The two Facet pump numbers are 610-1077 and 610-1078. They are Facet pumps, but also have Napa branding on them.

[Jeff G 78]

Jeff -

I believe Bruce would know exactly what to set that pressure at - my Mikuni's are set at 3.5 psi. Pressure regulator is a must in my opinion. Best of luck. Let us know on that dyno once you get it finalized.

Bruce suggested I talk to Steve in the shop, but nobody has been answering the shop number when I call. I'll try again tomorrow.

[beermanpete]

The factory pump provides 3.4 to 4.3 PSI.

We have our regulator set to 4 PSI and the car works well.

[Captain Obvious]

The two Facet pump numbers are 610-1077 and 610-1078. They are Facet pumps, but also have Napa branding on them.

After much digging and cross referencing**:

NAPA 610-1077 contains Facet pump number 40106

NAPA 610-1078 contains Facet pump number 40104

Slightly more info for those two pumps can be found here:

http://www.facet-purolator.com/index.php?option=com_content&task=category&sectionid=7&id=16&Itemid=31

PART # MAX-MIN PSI GPH

40104 4. - 1.5 25

40106 7. - 4 32

I still don't know what the specs mean, but here... This graph should clear it all up.

This is what happens when Marketing asks Engineering for some documentation that they can put on the website that couldn't possibly cause anybody to actually be able to be held accountable for anything at anytime.:mad:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~

**Here's the NAPA page for the 610-1077 -

https://www.napaonline.com/Catalog/CatalogItemDetail.aspx?R=BK_6101077_0334661226

on that page it lists the mfg #NAP12SV.

Here's a pdf catalog from Facet/Purolator -

http://www.facet-purolator.com/images/facet_guide_2004.pdf

At the end of that catalog it lists the solid state cube pump P/N FEP 12SV

At this point, it's pretty clear that the NAPA 610-1077, Facet FEP 12SV, and Purolator PRO 12SV are all the same thing.

Then on this page -

http://www.facet-purolator.com/index.php?option=com_content&task=category&sectionid=5&id=38&Itemid=62

there's indication that the FEP12SV and PRO12SV are clamshell kits containing a pump number 40106 and other associated items.

Similarly (without listing all the intermediate steps), the NAPA 610-1078 is a clamshell containing the 40104 pump.

[Captain Obvious]

Just found one more interesting piece of info. On this website (which looks like a Chinese second source to the 40106 pump)

http://www.aliexpress.com/store/301124/209377070-452432241/Facet-Red-Top-Electric-Fuel-Pump-40106-squre-shape-.html

It lists a curious spec "Shut-off pressure : 4-6psi"

The implication to me is that these pumps, being solid state and all, have actually got some pressure sensing technology in them and the pumping action is actually controlled to maintain the pressure between the two pressure points listed.

In other words, the implication is that the 40106 pump will turn off when the outlet line pressure is above 7 psi, and will turn back on again if the outlet pressure is below 4 psi. And if you stay in the hysteresis band between those two limits, the pump will always run.

So, if you've got a pressure regulator between the carbs and the return to the tank you just pick the Facet pump that has your regulators pressure at approx the middle of it's operating range.

This is all inferred, of course.

[240260280z]

I refreshed a clacker pump from a 240z and I vaguely recall some sort of pressure regulation inside with a spring.

If you can monitor O2 when you hit high rpms, if it is lean then it is fuel delivery, if it is rich then most likely it is spark (un burned fuel).

I had a 240z bog at high rpms and I thought is was fuel problem. I chased my tail checking everything and it turned out to be a spark issue.

[Jeff G 78]

Wish me luck tomorrow. I will go through the list and see what I can do to fix the issue. I was able to find a Spectre regulator just like the one beermanpete showed earlier in this thread. I wasn't able to find a gauge yet, but I do have the little tiny 0-10 psi gauge that I can use until I find a bigger one. I will have lots of things to check and swap tomorrow and hopefully I find SOMETHING that gives me hope that the problem is fixed.

Since I found a regulator, I will use the 4-7 psi pump and I have a new Bosch FI canister fuel filter from my '78 that I can use before the pump. It should provide good flow and have lots of filter media.

Should I try to keep the return to start with and run the regulator in the return line? What about the mechanical pump - should I remove it right away, or keep it in series to start with?

[Travel'n Man]

1 to 10 psi should be fine if you have your fuel pressure regulator set - mine is below for reference if needed.

[Captain Obvious]

Should I try to keep the return to start with and run the regulator in the return line? What about the mechanical pump - should I remove it right away, or keep it in series to start with?

Hmmm... I'm no expert on this stuff and I would gladly defer to someone else who's been through this before, but I guess I would come out of the gate with this:

• Mechanical pump still attached, but outlet routed back to inlet (because there's still residual fuel inside and you don't want it spraying on your cooling fan). And the reason I would take the mechanical pump out of the loop is because it may provide an unwanted restriction to the electrical pump, and in theory, the electrical pump should be able to provide all the fuel the engines needs, even at WOT high RPM, right?
  
• Electrical pump mounted as close to the tank as possible (because the documentation for those cube pumps says that, while they are self priming and can do 12" lift, they are really pusher pumps).
  
• Regulator located after the last carb pickoff point from the rail, and then outlet of the regulator returning back to the tank.
  

Question... Are you running the original fuel rail? If so, what (if anything) are you planning to do with the original fuel rail "regulator" restriction orifice? If you're installing a real regulator elsewhere, I would remove that orifice. You don't want a pressure drop there anymore. You could drill it out or cut an inch off the end of the hard return line tip.

And... "Good luck. We're all counting on you."

PS - Crap! I was out late last night and didn't check the forum when I got in... Just looked at the posting time, and you're already on the track!

Edited October 1, 2011 by Captain Obvious
Looked at the time...

[Jeff G 78]

Quick update... No, the race isn't until NEXT weekend. This weekend is all about getting everything diagnosed and the pump installed.

Facet pump is installed as WAS the Spectre regulator. Pump works fine, but the regulator appears to not work. With the regulator in place, no fuel flows past it. With it gone, the pump flows properly. The regulator has a In and Out marked which were checked.

The carb inlets were clean and the float heights were fine per the FSM. I haven't tuned it yet due to yet another several issues. We installed a thermostat and one of the bolts felt soft upon tightening. Sure enough, it leaked and when removed, the housing was partially stripped. A Helicoil solved that problem and the leak is gone. Next, we readjusted the valves. Most were fine, but a few needed some minor adjusting after the track day and a fresh valve job. The next issue is that we started it up and it ran great, except we have no oil pressure or temp showing on the gauges. Before, the temp would climb to 120 and the oil pressure worked just a few days ago. They are both completely dead now. I can't see anything wrong, so now I'm off to check the archives for how to check the gauges. The cam lobes have fresh oil, so I know it's just the gauges. Everything is hooked up as it was a few days ago when they worked.

We haven't made near the progress I had hoped today, but we still have time to get it done.

[Travel'n Man]

Jeff -

Left you a PM........

[Jeff G 78]

In for the night. It was a long day, but we made some progress, I think. Per my last note, the 4 - 7 psi pump is in place and working. According to my crappy little gauge, it is putting out about 3.5 psi with no load. I need to find a real gauge and a long hose to see what I'm getting on the track.

I found the issue with the temp and oil pressure gauge. My teammate was cleaning up wiring and cut a power wire that fed them. Interestingly, the temp gauge does work. That means that for the past two years the temp has never gotten above 130F even when it was 80F ambient. With the thermostat in place, the temp gauge came up to just below the mid point just running it in the garage. I bought a 180F fail safe gauge BTW made by motorad. I think that's the same brand that MSA sold me when I bought one for my 280 a few years back.

I still need to tune the carbs with the floats adjusted and the thermostat in place. I took the front fuel filter out to install the regulator and I then put it back in when I had to remove the regulator. It was the easiest way to make the hoses that I had work out. Prior to using the electric pump, the filter was always about 1/2 full, but now it's completely full of fuel. I guess that's a good sign that I have more flow. The mechanical pump is gone and we installed a block off plate. I still have the return line in use right now, but I will keep an eye on the pressure and block it if needed. I am still using the OE 260 fuel rail that is similar to a 280 rail with a return loop. If I quit using the return, I will need to come up with a safe way of blocking the hose. I guess I could install the regulator in it that won't flow anything.

Tomorrow I will tune the carbs and check timing, compression, leakdown, vacuum, etc. At least I don't have any more leaks from the water neck. The helicoil did the trick. It's always good to have a M8x1.25 kit handy.