Fuel Accumulator Question

[EIPtuningR32]

is there any way to bypass a fuel accumulator? and is there any downside to doing so?

[EIPtuningR32]

im tired of my car sitting... and i dont have $425 to spend on it

[MPDano]

$200 Good Used at 928 Intl with a 1 Year Warranty.

[EIPtuningR32]

Originally Posted by MPDano

$200 Good Used at 928 Intl with a 1 Year Warranty.

high pressure fuel line and clamps wont work?

[waynestrutt]

My 80 has never had one as long as I have owned it [ since 86].I never realized that until last november ,so what besides the accumulator have I been missing for the last 100k km? I would think that just a good check valve should suffice to keep the pressure in the line between startups.

[AirtekHVAC]

I am intrested to hear more input on this...I don't know if mine is bad, but it sure don't look good....

[EIPtuningR32]

mine was bad. The car wouldnt start if it was hot, but it would if it was cold.

So if your car works without one, i assume mine would to... i think ill try the HP fuel line and clamps method.

[JK McDonald]

Hey EIPtuningR32, The fuel accumulator is only installed to smooth out any minor fluctuations in your fuel pressure (similar to a shock absorber) as you drive your car and to maintain a residual pressure in the fuel lines after shut down to help during a restart. It is basically a canister with a rubber bladder in the middle, a spring in the top half and fuel stored under pressure in the lower half. There are many Bosch style fuel accumulators on the market that are interchangeable between vehicles. As long as the connections are similar and the internal capacity of an accumulator is relatively close – it will work. For example I often install one designated for a 6 cylinder Volvo on 911 Porsche – at half the price. Search on the internet under Bosch Fuel Accumulator rather then one for a specific model car and you’ll see lots of photos that will help in identifying a substitute. By the way the one needed for a Porsche, Mercedes, BMW - V8 engine is a big mother and they are all pricey....

If you are having trouble with your accumulator one other temporary option (until you buy a new one) is to install an axillary toggle switch to manually energize the fuel pump relay. This can often help during start up. Normally the fuel pump relay/fuel pump on a CIS injection car is initially turned on when the ignition switch is in the start position. Once running there is an small switch on the fuel control unit that looks for movement of the air control arm and keeps the fuel pump running. If your fuel line check valves are sealing properly and the accumulator is working, a cold or hot restart is normally no problem.

By temporarily installing an aux toggle switch to apply a ground to the fuel pump control relay, you can force the fuel pump to pressurize your fuel lines (negating the accumulator) before you even begin to apply the starter.

Please note – once you are running, turn the added aux toggle switch off. This allows air flow switch to control the fuel pump as the system was designed to do. The air flow switch is a safety circuit that will turn off the fuel pump if the engine shuts down for any reason.

Good Luck, Michael

[Plexus928]

Delete, at worst your starter might have to spin the engine for another second while the fuel pump pressurises the line prior to starting. cut off the threaded fittings and silver solder on a couple of olives. As you can see from the fuel staining where it used to live , car definately better off without it.
EDIT_ sorry, this pic shows more of the emmission hoses, better pic'on later post

[AirtekHVAC]

Dang...I never thought of that....and considering I have rewelded mower decks with coat hanger rod, seems like something I would have come up with! I gots lots o silver solder!

[Luis_M]

Plexus928: Consider replacing that 30r7 spec hose with something tougher, like EFI hose. You know the fuel pressure is about 75psi in that wheel well there....

[whatudrivin]

Get the 30R9 hose (100psi) or the Gates Hose with Green Shield. That stuff is good up to 255 psi.

[AirtekHVAC]

good Eye Luis...I am in the process of redoing all mine, and did not catch that....I got the Gates Barricade stuff....not too expensive...got mine at O'reileys, but hate their clamps...

[whatudrivin]

That Gates hose held enough pressure that the front face of my fuel pump blew out before any leaks or stress were noticed anywhere else.

[Jadz928]

Originally Posted by EIPtuningR32

is there any way to bypass a fuel accumulator? and is there any downside to doing so?

I heard you could substitute it for a coiled loop of high pressure rated fuel line. The coils basically make a "pee trap" to keep fuel up in the feed line once fuel pressure is released.

I've have no direct experience doing this. Do your research. YMMV.

[MPDano]

Geezus, remove those clamps and put FI Clamps on there. You cannot use those clamps on high pressure hoses.

[EIPtuningR32]

are the olives necessary?

[AirtekHVAC]

Plexus...what did you do for a fuel filter?

[Plexus928]

I agree with swaping the clamps,only ones I had available when doing a test set up. there are two lines there, the supply line (the one that is only about 8 inches long)is high pressure, the branded line is connected to the one way valve/emission, not pressure.
I left enough space when I cut off the threaded fittings for an in line filter, probably put one there when I uprate the fuel pump, at the moment have standard pump/filter set up.
You will need the olives, regardless of clamps, without the olive/shoulder there will be a risk of the line blowing off

[AirtekHVAC]

Ahhh....I think I may have to do this...I wanted stock, but mine is so F'd up, that might not be feasible at this stage. Priority one is to get it to run and assess the mechanicals before I go full bore on it.