Author Topic: Fuel Pressure Testing Equipment  (Read 3817 times)

PeterPortugal

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Fuel Pressure Testing Equipment
« on: March 13, 2018, 17:14:26 »
Guys,

Can anybody recommend me a kit (available on Amazon ideally) which is suitable right out of the box to test the fuel pressure at the cold start solenoid valve, fuel filter, etc. Let's call it the low pressure side.

There are millions online and I don't want to pick a useless one !

Regards

Peter
1963 220se Cabrio
1968 280se Coupe

WRe

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Re: Fuel Pressure Testing Equipment
« Reply #1 on: March 14, 2018, 07:21:08 »
Hi Peter,
here you find some inspiration: http://w113.eu/Shop/mano.jpg.
...WRe

PeterPortugal

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Re: Fuel Pressure Testing Equipment
« Reply #2 on: March 14, 2018, 10:21:44 »
Hi WRe,

Thanks for the reply. I had seen that already and intend to buy it....along with some of the other really useful parts that Wolfgang produces.

I have 3 areas I want to measure
1. Fuel pressure after the filter (0.4 atm) - I will use the device available from W113.eu
2. At the cold start valve (0.6 - 0.8 atm) with fuel circulating
3. At the cold start valve (1.2 atm min) with fuel flow blocked at the return to the tank
I still need something to connect to carry out tests 2 & 3

What I notice on many of the pressure measuring kits available is that they are for modern vehicles which have test connections (schrader valves). I am working away from home and so have no idea what sort of connection is on my cold start valve. I would just like to buy a kit which is waiting for me when I get back and has the connections necessary for the job.

I have a 1963 220seb by the way....before anybody with a Pagoda tells me the pressures I quoted are wrong !

Regards

Peter
1963 220se Cabrio
1968 280se Coupe

Shvegel

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Re: Fuel Pressure Testing Equipment
« Reply #3 on: March 14, 2018, 10:30:10 »
Are not all of the tests listed after the fuel filter?  I am not clear on how the pressure can vary from any of the points listed as they are all part of the same pressure area between the filter outlet and the restriction at the outlet of the injection pump.  You should be able to take all the pressures from any point in that system and simply block the return hose for the last test.
« Last Edit: March 15, 2018, 01:42:37 by Shvegel »

mistertj

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Re: Fuel Pressure Testing Equipment
« Reply #4 on: March 14, 2018, 10:44:00 »
Hi Peter,
I believe that this might be what you are looking for. The adapter is 14mm and screws into the top of the fuel filter case. Hopefully you can read the Amazon info from the photo.

PeterPortugal

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Re: Fuel Pressure Testing Equipment
« Reply #5 on: March 14, 2018, 12:27:35 »
Guys,

Thanks for your responses. I can read the picture easily, which is great.

I was also confused about how the pressure could vary for the first two tests (with the fuel return open). I have consulted the manual again and it does seem to offer conflicting info. See pictures attached.

Having read the info on W113.eu I believe that the 0.4 value is a minimum and the 0.6 to 0.8 atm is optimum.

As many people have pointed out on the forum though, the flow is more important and I will be checking this too.

Thanks again for your support.

WRe....if you are in fact Wolfgang then note that the gauge should be able to read a higher pressure than 1atm to do the test with the fuel return blocked.

Regards

Peter
1963 220se Cabrio
1968 280se Coupe

WRe

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Re: Fuel Pressure Testing Equipment
« Reply #6 on: March 14, 2018, 13:40:29 »
Hi Peter,
I'am Wolfgang too but not 'Wolfgang Roadbook" :-).
...WRe

PeterPortugal

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Re: Fuel Pressure Testing Equipment
« Reply #7 on: March 14, 2018, 14:37:21 »
Hi Wolfgang,

The Roadbook Wolfgang offers some great solutions and deserves some publicity on this board.

Thanks for answering my post and advising me.

Regards

Peter

1963 220se Cabrio
1968 280se Coupe

Shvegel

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Re: Fuel Pressure Testing Equipment
« Reply #8 on: March 14, 2018, 21:04:18 »
If you do have issues with the flow remember there is a screen in the tank as well as in the inlet of the fuel pump.

PeterPortugal

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Re: Fuel Pressure Testing Equipment
« Reply #9 on: March 15, 2018, 07:18:25 »
Shvegel,

I have bought a new tank filter....and to fit it a 22mm hexagon wrench which cost me more than the filter itself !

Regards

Peter
1963 220se Cabrio
1968 280se Coupe

Kevkeller

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Re: Fuel Pressure Testing Equipment
« Reply #10 on: March 15, 2018, 16:33:49 »
Hi Wolfgang,

The Roadbook Wolfgang offers some great solutions and deserves some publicity on this board.

Thanks for answering my post and advising me.

Regards

Peter

I’ve never heard of this book and can’t find it. What and where is it?

Kevin
1970 280 SL

WRe

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Re: Fuel Pressure Testing Equipment
« Reply #11 on: March 15, 2018, 17:16:47 »
Hi,
see here: http://w113.eu.
...WRe

dirkbalter

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Re: Fuel Pressure Testing Equipment
« Reply #12 on: March 15, 2018, 20:00:28 »
Shvegel,

I have bought a new tank filter....and to fit it a 22mm hexagon wrench which cost me more than the filter itself !

Regards

Peter


Peter, probably to late for you but a 14mm bolt (22mm wrench) with a couple of nuts works fine as well.

Dirk
Dirk
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BaronYoungman

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Re: Fuel Pressure Testing Equipment
« Reply #13 on: March 15, 2018, 21:44:26 »
Also keep in mind besides the screen filter on the bottom of the fuel pump( 27mm) if the one way valve on top of the fuel pump (22mm) gets clogged with rust or old gelled gas or other particles it will lodge half way open and imped the flow.
Bob
Bob "Baron" Youngman
1971 280 SL silver  1 car 0 boxes
1983 500sec Wheeler Dealer AMG Widebody
1985 500sec Paris Autoshow AMG coupe
1994 320sl wifes car
1988 560sec  Japan "Yakuza Car"

ja17

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Re: Fuel Pressure Testing Equipment
« Reply #14 on: March 17, 2018, 15:00:47 »
Most standard water or air pressure gauges from a hardware store will work on these low pressure fuel systems. Find a 30 psi gauge. If you are using it often,  buy the expensive, specialized equipment. Otherwise the standard gauge will do for occasional use.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback