Rebuilding CIS fuel lines
Thread Starter
Nordschleife Master
Joined: Jul 2003
Posts: 7,743
Likes: 78
From: Minneapolis
Rebuilding CIS fuel lines
What's are the good approaches for replacing hose on CIS fuel lines? My cars have the '79 to early '80 version of the lines. Got those odd fittings that make countermen say "Hmmmm."
My plan now is to get some fuel injection (high pressure) line from NAPA and have Pirtek replace the rubber lines. They'll make the right collets and do a quality 8-way crimp. NAPA offers ordinary lines and "better" ones with multiple layers. The hose that seems to work is 5/8" OD so gets 3/8" ID or 10mm.
The guy at Pirtek really wants to put in sweet stainless hose with teflon cores. The estimate including cutting and welding of the fitting is about $150. $35 to replace rubber.
Thanks.
My plan now is to get some fuel injection (high pressure) line from NAPA and have Pirtek replace the rubber lines. They'll make the right collets and do a quality 8-way crimp. NAPA offers ordinary lines and "better" ones with multiple layers. The hose that seems to work is 5/8" OD so gets 3/8" ID or 10mm.
The guy at Pirtek really wants to put in sweet stainless hose with teflon cores. The estimate including cutting and welding of the fitting is about $150. $35 to replace rubber.
Thanks.
Rennlist Member
Joined: May 2012
Posts: 319
Likes: 2
From: 88 928 S4 in Dallas, TX
I had a line blow on my Mercedes Benz 91 560SEL due to old age. It was the line that goes to the fuel distributor on those cars. The 91 used CIS-E which runs at a higher pressure to CIS and uses to fuel pumps.
I bought some fuel injection hose and a couple of stout fuel injection hose clamps and put it together. It was problem free until I finally killed the car.
I bought some fuel injection hose and a couple of stout fuel injection hose clamps and put it together. It was problem free until I finally killed the car.
Rennlist Member
Joined: Dec 2002
Posts: 5,283
Likes: 52
From: Australia
I was able to get the rear filter to accumulator hose geneuine a couple of years ago, and the delivery line from the steel pipe to the engine up front, for my 83 S, but these may be different in your earlier model. The return line in the engine bay was NLA then. I would have thought they could recover the fittings and re-crimp to them if they know their business well.
jp 83 Euro S AT 55k
jp 83 Euro S AT 55k
Shameful Thread Killer
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Joined: Aug 2004
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From: Rep of Texas, N NM, Rockies, SoCal
I have a Ferrari with CIS. I had one injector hose that looked quite bad and I had to replace it. Once I got the old hose off without abrading the metal barbed area which is a lot of work, fitting the new hose was not much fun. Here's what I did.
Get a simple tubing flare kit which has the multi sized clamping/pinching tool, which is at the bottom of this picture; http://www.sears.com/eastwood-brake-...SPM6316703904P
Find the one that will pinch the black FI hose without crushing. If you don't have the right size, go slightly larger. It should be snug but not crush the black FI hose. Put one or two wraps of simple scotch tape around the FI hose about 3/4" above the end where you are going to clamp. Now, boil some clear water, and just leave the FI hose in there while it heats up with the clamp on the FI hose. The hose end which is going on the barb needs to be fully immersed. Get the injector or the fitting ready on the vise so that it will not move. Once the water boils for about 5 minutes, take it out with a gloved hand, and quickly move to the injector and push it firmly and straight down onto the injector top or fitting as needed. Try to do it all in one motion. Let it cool and remove the tubing flare clamp and tape. Repeat as necessary for the other end the same way.
After I did the two, I made a quick jig to apply compressed air to test before fitting. I put 155PSI air on it for about 3 hours and left it in the sun. This is about 3x the working pressure and had no problems.
Get a simple tubing flare kit which has the multi sized clamping/pinching tool, which is at the bottom of this picture; http://www.sears.com/eastwood-brake-...SPM6316703904P
Find the one that will pinch the black FI hose without crushing. If you don't have the right size, go slightly larger. It should be snug but not crush the black FI hose. Put one or two wraps of simple scotch tape around the FI hose about 3/4" above the end where you are going to clamp. Now, boil some clear water, and just leave the FI hose in there while it heats up with the clamp on the FI hose. The hose end which is going on the barb needs to be fully immersed. Get the injector or the fitting ready on the vise so that it will not move. Once the water boils for about 5 minutes, take it out with a gloved hand, and quickly move to the injector and push it firmly and straight down onto the injector top or fitting as needed. Try to do it all in one motion. Let it cool and remove the tubing flare clamp and tape. Repeat as necessary for the other end the same way.
After I did the two, I made a quick jig to apply compressed air to test before fitting. I put 155PSI air on it for about 3 hours and left it in the sun. This is about 3x the working pressure and had no problems.
Thread Starter
Nordschleife Master
Joined: Jul 2003
Posts: 7,743
Likes: 78
From: Minneapolis
I should have been more clear on the lines. These are the pressure and return lines that are in the engine bay. The return is OK but the pressure blew out at one end.
Thanks for the input. I thought Greg had these and/or Mark. Carl offers hose but no sets. I got two kinds of high-pressure 5/8" OD line from NAPA and will have them rebuild with that.
Thanks for the ideas.
Thanks for the input. I thought Greg had these and/or Mark. Carl offers hose but no sets. I got two kinds of high-pressure 5/8" OD line from NAPA and will have them rebuild with that.
Thanks for the ideas.
Former Vendor
Joined: Feb 2005
Posts: 15,228
Likes: 2,530
From: Anaheim
I make both the fuel and return lines, in the engine compartment, as well as all of the lines in the rear, to and from the pumps.
I also make all of the lines to the injectors, cold start valve, and warm-up regulator.
I had all of the metric ends for the large feed and return lines custom made in Germany. The ends required on the fuel distributor, injectors, cold start valve, and warm-up regulator I had custom made by Goodridge, in the UK.
All are made from Goodridge Teflon lined hose and have a lifetime warranty.
Roger, at 928 R US, stocks them all.
I also make all of the lines to the injectors, cold start valve, and warm-up regulator.
I had all of the metric ends for the large feed and return lines custom made in Germany. The ends required on the fuel distributor, injectors, cold start valve, and warm-up regulator I had custom made by Goodridge, in the UK.
All are made from Goodridge Teflon lined hose and have a lifetime warranty.
Roger, at 928 R US, stocks them all.
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Michael S. Palmer
Instructor
Joined: Jun 2009
Posts: 220
Likes: 1
From: gone to Pelican - search for reanimotion
I'm going to purchase a set of the main feed lines, is there any merit to replacing the CIS hard lines? and does anyone have a photo of the components for a 16v Euro S - loose or installed.
Rennlist Member
Joined: Dec 2002
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From: Australia
What do you call "components for a 16v Euro S" ? Distribuor head, WUR, Vacuum regulator, solenoid for dropping control while half hot, cold start injector, thermotimer, etc ?
I would not have thought there was any value in rep;lacing CIS hard lines, unless you know there is something really wrong with them.
Greg B - whats your definition (or the maker's) of 'lifetime warranty' ?
jp 83 Euro S AT 55k
I would not have thought there was any value in rep;lacing CIS hard lines, unless you know there is something really wrong with them.
Greg B - whats your definition (or the maker's) of 'lifetime warranty' ?
jp 83 Euro S AT 55k
Instructor
Joined: Jun 2009
Posts: 220
Likes: 1
From: gone to Pelican - search for reanimotion
Sorry, by components I meant the custom lines, not the Bosch parts.
There are photos of Mr Brown's artwork in a few threads for later efi and 32v engines, and the feed lines for a 79?, Greg mentioned above he made the lines between the Distributor/Injectors/ColdStart/WUR, Carl has previously done he same.
As the factory lines are hard lines - and the Euro S has slightly larger diameter lines (?) - and hard lines are better behaved and stay where they are placed
, I'm also of the opinion there is little need to change them. The flex lines on the other hand are a must do.
There are photos of Mr Brown's artwork in a few threads for later efi and 32v engines, and the feed lines for a 79?, Greg mentioned above he made the lines between the Distributor/Injectors/ColdStart/WUR, Carl has previously done he same.
As the factory lines are hard lines - and the Euro S has slightly larger diameter lines (?) - and hard lines are better behaved and stay where they are placed
, I'm also of the opinion there is little need to change them. The flex lines on the other hand are a must do.
Rennlist Member
Joined: Dec 2002
Posts: 5,283
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From: Australia
FWIW, when I replaced my tank, the rear hose from filter to accumulator, and the front high pressure hose in the engine bay a few years ago, I had both front hoses out, and found both were in VERY good condition - no signs of cracks AT ALL when flexed very tightly. I replaced the pressure line because it was available, but the return hose was NLA. My car had done 7 years in UK from new, and 9 years in Saudi (temps to 120F), so it must have lived indoors a lot. Since then I have sleeved the front pressure hose in stuff called Firesleeve - fibreglass tube covered in heat resistant red silicon - which should protect the hose from engine heat, and constrain any leaks to dribbling down inside rather than spraying everywhere. I should still have the old hoses somehwere if pics of those would help ? I suspect you rear hoses are different from later cars?
jp 83 Euro S AT 55k
jp 83 Euro S AT 55k
Instructor
Joined: Jun 2009
Posts: 220
Likes: 1
From: gone to Pelican - search for reanimotion
Mine are fine also - the engine bay lines are showing minor signs of surface cracks in the layer above the outer reinforcing cloth but are still solid and pliable, the pump to accumulator line is also in very good condition. I've replaced or renewed virtually everything else, so the fuel hoses are next in line "Just to be sure" 