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87m491
Have just done the whole soft fuel system soup to nuts and I am buttoning up the engine compartment. I went to remount the MPS and the service port on the fuel rail is hitting the MPS body dead center.

IPB Image

The fuel elbows to the injectors are new and not as pliable as the originals, though a fair bit shorter so any interference should have been less than with the originals. Any one else run into this? Tilting the rail forward or back does not seem to help much as this port hits right in the widest portion of the MPS. Now I know why them MPS only had the top bolt properly installed and sheet metal screws in the bottom two holes.



914_teener
I think that fuel rain goes on the driver side not the passenger side IIRC.

Also...it's easier to put the screws in first and then slip the MPS into it. Then getting to the bottom one is a PITA.
saigon71
The rail is on the correct side.

It's tight in there! I recommend using the pre-formed fuel injection hoses on the passenger side instead of simply using regular FI hose. It will give you a little more room. Even using them, I only have about 1/8" of clearance between that fuel rail bolt and my MPS.

JeffBowlsby
Factory photo does not show the fuel pressure gauge port on the passenger side. It does not conflict with the MPS when its on the drivers side.
914_teener
Yep....and here is a picture of a 74 2.0 with 47k original miles that I took this morning looking down from the drivers side at the Luftenkult.

Looks to me like it is on the drivers side.

Click to view attachment
914_teener
Here is the other side just for kick and giggles.

Click to view attachment
87m491
Whoa, that is one busy engine compartment with FP regulator and MPS on the same side. To be clear on my car the test port is factory blocked off AFAIK. Car is a 74 2.0. The port on the drivers side rail is open and feeds the cold start injector. Might be worthwhile to find a VW unit with no port at all to grab 10mm of space.
914_teener
On the 1.7's the port is on the end of the fuel rail on the drivers side and the CS injector is teed from the middle of the feed line.

Not so sure that what you have is the correct fuel rail. Give Bruce Stone a PM he has them all plated and blinged up.
914_teener
QUOTE(87m491 @ May 7 2017, 02:59 PM) *

Whoa, that is one busy engine compartment with FP regulator and MPS on the same side. To be clear on my car the test port is factory blocked off AFAIK. Car is a 74 2.0. The port on the drivers side rail is open and feeds the cold start injector. Might be worthwhile to find a VW unit with no port at all to grab 10mm of space.


FP regulator is on the driver side in the pic I posted it is on the right side.
JeffBowlsby
QUOTE(87m491 @ May 7 2017, 02:59 PM) *

Whoa, that is one busy engine compartment with FP regulator and MPS on the same side. To be clear on my car the test port is factory blocked off AFAIK. Car is a 74 2.0. The port on the drivers side rail is open and feeds the cold start injector. Might be worthwhile to find a VW unit with no port at all to grab 10mm of space.


That's not a FP regulator above the MPS...take another guess what it is.
iankarr
Decel valve?
JeffBowlsby
QUOTE(cuddyk @ May 7 2017, 03:40 PM) *

Decel valve?


sunglasses.gif You nailed it.
iankarr
QUOTE(Jeff Bowlsby @ May 7 2017, 06:49 PM) *

QUOTE(cuddyk @ May 7 2017, 03:40 PM) *

Decel valve?


sunglasses.gif You nailed it.

Thanks, professor!
914_teener
Jeff....you are much nicer than I am.
iankarr
QUOTE(914_teener @ May 7 2017, 07:01 PM) *

Jeff....you are much nicer than I am.

lol-2.gif
saigon71
Interesting...

I've got nipples on both my fuel rails. The drivers side is connected to the FI system - cold start valve? I've always used the passenger side to check fuel pressure.
jcd914
With a couple of wire ties around the intake runners and the fuel rail you can gently pull the fuel rail toward the intake runners and away from the MPS. Watch the injector elbows, you don't want to kink the hose and you don't want too much tension on the injectors.

Jim

87m491
Not too much give on the relatively short, and stiff new lines. I will try again. I think it might be easier to find another rail without the port. Surprisingly, I have not find a VW site that lists them yet....


QUOTE(jcd914 @ May 7 2017, 07:59 PM) *

With a couple of wire ties around the intake runners and the fuel rail you can gently pull the fuel rail toward the intake runners and away from the MPS. Watch the injector elbows, you don't want to kink the hose and you don't want too much tension on the injectors.

Jim

bdstone914
To my knowledge all Type IV injected engines used one rail with a port and one without.
I have many fuel rails but only those with ports are left, no rails without the test port.
BillC
87m491 --

According to the diagram here: http://www.pelicanparts.com/914/technical_...4_20FI_diag.htm , the '74 2.0 looks like it is supposed to have test ports on both fuel injector rails, with the driver's side test port feeding the cold start valve.

Check both rails, and see if one of the test ports is off-center. If so, that may be the one that is supposed to go on the passenger side. I'm just guessing, since I've never been that deep into a '74's engine compartment.

Also, when I re-did the fuel lines on my '73, the MPS bracket was held in with one machine screw on top and two sheet metal screws on the bottom. So yours may have been mounted correctly.

Are there any wear marks on your MPS, where the test port plug may have been rubbing before?

Edit: just had a thought: Are the new fuel injector elbows taller than the old ones you took off? Maybe you can trim the new elbows down to lower the rail and get the clearance you need.
TheCabinetmaker
I've owned and worked on cars from 73-76 of all engine sizes. Never have I seen one on the passenger side. There is very little clearance between mps and rail without the nipple.
arne
My late '73 2.0 also has ports on both sides, left to the cold start valve and right is capped.
87m491
The fuel rails are symmetrical right and left. I'd be very surprised if the lower bolts were supposed to use sheet metal screws given the bronze bushing installed rubber grommets at each mount, but then the bottom 2 holes did not have a welded capture but either.
As mentioned I used even shorter fuel hose elbows than stock so that should not be the problem.
I may just have the port removed and welded. I do not believe my MPS was properly installed with one machine screw and I'll fitting sheet metal screws (they came out by hand)


QUOTE(BillC @ May 8 2017, 06:01 AM) *

87m491 --

According to the diagram here: http://www.pelicanparts.com/914/technical_...4_20FI_diag.htm , the '74 2.0 looks like it is supposed to have test ports on both fuel injector rails, with the driver's side test port feeding the cold start valve.

Check both rails, and see if one of the test ports is off-center. If so, that may be the one that is supposed to go on the passenger side. I'm just guessing, since I've never been that deep into a '74's engine compartment.

Also, when I re-did the fuel lines on my '73, the MPS bracket was held in with one machine screw on top and two sheet metal screws on the bottom. So yours may have been mounted correctly.

Are there any wear marks on your MPS, where the test port plug may have been rubbing before?

Edit: just had a thought: Are the new fuel injector elbows taller than the old ones you took off? Maybe you can trim the new elbows down to lower the rail and get the clearance you need.

arne
FWIW - My MPS was also mounted with a single machine screw at the top, and two sheet metal screws in the lower spots. Coincidence?
87m491
Well, according to ETKA, sheet metal screws it was. Go figure!

QUOTE(arne @ May 8 2017, 05:51 PM) *

FWIW - My MPS was also mounted with a single machine screw at the top, and two sheet metal screws in the lower spots. Coincidence?

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