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Discussion Starter #1
HEY ALL SOMEONE HAD POSTED A P

HEY ALL SOMEONE HAD POSTED A PICTURE OF A FUEL ACCUMULATOR FOR A TR WITH A BOSCH PART # I HAVE MISPLACED THAT INFO. IF SOMEONE HAS THAT INFO THAT WOULD BE GREAT. AND WHAT IS THIS PARTS PRIME PURPOSE THANKS.
MIKE
 
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Discussion Starter #2
I don't know the part numb

I don't know the part number, but the purpose is to "soften" the flow pulsations caused by a running fuel pump.........keeps the flow smooth.
 
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Discussion Starter #3
Henry is correct. There is al

Henry is correct. There is also another purpose, and that is to maintain fuel pressure for a while after engine shut off, to prevent vapor lock.

By the way....Hi Henry...been following your exploits. You sure are busy lately. We are all learning a lot through your experiences...Thank You for posting. Hang in there!
 
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Discussion Starter #4
Hi Jeff: And I thought it was

Hi Jeff: And I thought it was the non-return valve, in the fuel pump, that holds the pressure.

So how is your TR coming along. Any more information on the leak? What have you decided?
 
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Discussion Starter #6
Sorry JR,
I beg to differ, pr


Sorry JR,
I beg to differ, presuming I'm understanding you correctly. The check valve and accumulator are on the pressure side of the system.

Here's how Auto-Solve describes the accumulator function.

The accumulator is the first of the components in the fuel system after the pump. This unit has an important role to fill in the operation of the Bosch K Jetronic system.
Its first job is to help smooth out any pulses in the flow of the fuel, this is achieved by passing the fuel through a series of baffles and into a chamber giving it slight capacitance and a much smother flow. Its other and possibly more important role is to maintain pressure within the system when the fuel pump has been switched off; this is achieved by the accumulator spring and diaphragm pushing against the fuel.
For the duration that the engine is running, the diaphragm will be against its stop within the spring's chamber. When the engine is stopped and all of the non-return valves close, the spring pressure against the diaphragm will maintain the residual or holding pressure and overcome any slight seepage.
Within the data books for this system, it is shown that the critical time for maintaining these pressures, is between 5 and 20 minutes. After a journey, when the engine is switched off, the under bonnet temperature increases causing the fuel in the lines to heat and it attempts to evaporate.
Maintaining the pressure eliminates this problem and ensures a clean start when the vehicle has been standing with a hot engine.


Fig. 6.2

Figure 6.2 shows an accumulator full of fuel.

 
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Discussion Starter #7
You are correct David..long da

You are correct David..long day..the other 'pressure valve' is in the side of the Fuel Distrib itself just in front of the return line.
 
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Discussion Starter #8
As usual f-talk comes through

As usual f-talk comes through again. I sometimes shake my head at the amount of information on this forum...priceless! I occasionally visit other fcar websites but f-talk is by far the best for technical information, respect, and class. That's why it's my favorite site.

I love the group answer to the question about the accumulator's function.

Hi Henry...and David...and JRV! As for my TR I've been procrastinating....but the engine is just about ready to drop out - again. I should have it out by the weekend. I'll try and post some pics of the situation.
 
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Discussion Starter #9
Jeff: Good luck......take it

Jeff: Good luck......take it easy, and don't get hurt. I wish I could be there to help you!!!
 
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Discussion Starter #10
Thank You Henry. At least thi

Thank You Henry. At least this time around I have much much less work to do than the last time. I'm getting pretty good at working on this darn car....and ya know I still don't regret it for a minute. I'll have so much knowledge that I'll be an expert when I go looking for my next Testarossa.
 
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Discussion Starter #11
Jeff: I am trying to get the

Jeff: I am trying to get the Boxer ready for the summer, because I feel that I may have the same problem, with the TR, as you are.

I recall, when I had a 328, that I had to buy a special tool to install the cam seals correctly. After installing one, without the tool, it leaked.

This may be true of the TR also, regarding the main seal. When you find the leak, let us know, before you install a new seal. I now know what this tool should look like, and I can machine one for you, if necessary.

So, find the problem, and let us know, before you go any further.
 
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Discussion Starter #12
Thank You Henry...will do. I

Thank You Henry...will do. I posted info. on another thread regarding those copper crush washers...I hope it helps.
 
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Discussion Starter #13
WOW WHAT A RESPONCE JR I HAVE

WOW WHAT A RESPONCE JR I HAVE AN 87 TR IS THAT THE SAME PART # AS THE BB?
 
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Discussion Starter #14
Hi MG,

sorry for the delaye


Hi MG,

sorry for the delayed reply.

No the BBi & TR are not the same..

the 87 TR takes a Bosch # 0 438 170 042

Regards, JRV
 
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Discussion Starter #15
As an interesting aside we are

As an interesting aside we are plumbing the fuel system in my P4. It's going to take 30 feet of fuel lines. It's a mechanical FI system with 2 electric pumps, one low pressure,one high pressure as well as a mechanical pump. It operates at 130psi! There's a cockpit PSI gauge, 2 fuel cells, two crossovers, one of which is heated by return engine water, an accululator tank, check valves, roll over valve return lines, etc. It's also interesting that the P4 gauges aren't illuminated. I guess if they wanted to read one at night they struck a match. I've added bulbs. I wonder if the judges will deduct for that...
 
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