Bosch 044 fittings

[Walt Fricke]

I'm replacing a used 2.7 Bosch fuel pump with the redoubtable Bosch 044 in my2.8 track car. May be overkill, but one thing the 044 allows is finally doing away with any use of hose clamps in the fuel system.

I know I can purchase an M18x1.5 to -6AN fitting for the inlet side. But what about the outlet?



First off, with Electromotive fuel injection do I need the top fitting, which I take to be a residual pressure valve/make sure there is pressure before opening valve? This is a race only car. If I remove it, I can use an M12x1.5 to -6AN fitting and I am done. Otherwise I have to find a 12.5mm banjo to -6AN banjo fitting (which I am not finding easily), and then find an M12x1.5 cap nut. Washers I have.

Secondly, whether or not I use a banjo, can't I dispense with the intermediate fitting? The one between the aluminum top plate of the pump and the RPV? It has the same threads on both ends, so all it seems to do is act as an extender. Yes, that gets the banjo or anything else out away from the electrical connections, but what issue I may not have imagined would arise if I dispens with this fitting?

Walt

[JFairman]

The intermediate fitting is a spacer so you don't need it and the long threaded one is the check valve for the pump, you do need that.

You need a banjo fitting and cap nut for the check valve. They are available in AN and the cap nut is too. A 930 front pump cap nut will work with an AN banjo fitting and others would too.

[Mahler9th]

I run an 044 in my race car as do many of my friends. In all of our configurations, the check valve is removed. So we can use a commonly available alu or steel adapter. Sometimes Ii buy steel parts from BAT, but Earl's or Aeroquip are more common in my car.

If you need something special for some reason, you can reach out to JWE as they may have a small inventory of special adapters. There are very few puzzles they haven't seen and solved.

- Mike

[Walt Fricke]

Interesting, Mike.

I've been wondering how important the check valve is in an EFI system. I know that on the CIS systems you need a functioning check valve to keep the residual pressure up within the Porsche specs. It goes down over time, but so does the temperature of the important parts, which I assume means you don't have hot start problems.

But with EFI why do you need to keep that pressure up? Isn't it going to build almost instantly as soon as you try to start the motor?

Or is it an issue of boiling temperature - higher with pressure, so residual pressure keeps the fuel out where it is hot from boiling until things cool? Preventing vapor lock? But if lots of guys with EFI don't use an RPV, and don't have hot start issues, what's the deal? Parts not installed can't break and cost nothing, etc.

As it turns out, I got a suitable Banjo from Pegasus, and the M18x1.5 intake fitting from (I hppe) RPW. I also got the banjo end cap nut - it is steel, and shipping cost 3x what the part cose. As best I can tell, you have to go to England to get an aluminum M12x1.5 end cap.

[JFairman]

The bosch fuel pump check valve banjo fitting doesn't need to be there with EFI. There is usually no fuel pressure accumulator to store some residual fuel pressure up to 24 hours after shutting off the motor with EFI anyway.
I'm so used to CIS on an old 930 these days I forgot about EFI not needing it so I removed that from my earlier post.

For the fuel inlet fitting on the 044 pump, Turbokraft makes a nice one piece fitting if using a 12mm ID hose and clamp for a street car gas tank set up.
TurboKraft : Catalog Home : Fuel Pump Adapter Fitting : Bosch 044 [999 620 993 TK] - $34.00
Or use an 18x1.5mm metric adaptor fitting with AN fitting for a race car. There are lots of places to buy those.

If it's a competition car it's good to use 2 or more fuel pumps in parallel for plenty of fuel volume and backup so the car will keep running if one stops working during a race.

[KTL]

BAT Inc. has the cap on page 4 top right

http://97.74.32.155/files/metric.pdf

Pegasus rocks (I see you looking thru their catalog). Most everything in stock and ships same day. I can get stuff in a day from them, being nearby in IL. Can't beat that with a stick!

[BoxsterGT]

In case anyone is in need, I make these custom fittings for the 044 pump when using either M14 or M16 hoses...........




I also stock the correct Banjo & Cap Nut & Copper crush washers to complete the install.....



The M16 size matches what is used for the all 3.6 & larger factory systems.

Len at Autosportengineering dot com

[SteamWolf]

If you remove the spacer, make sure the fitting doesn't bottom out when you tighten it up, or it'll damage the pump.

The only other reason to leave it in is without it, it's damn hard to get a spanner in there!

[Walt Fricke]

I figured as much for the purpose of the spacer, but without the check valve part, you can tighten the hollow bolt part nicely on the bench, and should be able to expect it to stay tight even while loosening the cap nut as might be needed while it is in the car.

[d.a.autry]

BoxsterGT, are you still on this thread?

Looking for those fittings you mention and it seems the page you referenced is 'under construction'. Would like to speak with you regarding the fittings.

Thanks!

[BoxsterGT]

Yes, I can help.

Best to email me..... len dot cummings at verizon dot net

or

go to my user name above left corner and pick "send email".

[lvporschepilot]

I used an m12 to 6an check valve I snapped up off ebay for under $25 shipped just two days ago. If you don't want a check valve then an m12 to 6an adapter is under $10, again on ebay. I mated it all with a 90 degree 6an swivel head which met up with my 6an main fuel line through the tunnel. Used 2 3/8" aluminum tubes for feed and return, works awesome and is a permanent solution not to mention very clean.