Alfa GTV6 Fuel Pump Hose Replacement

 

The Alfa Romeo GTV6 fuel pump hoses have a unique routing that have hoses with 180 degree bends.  Naturally, these hoses are no longer available. Even if they were available, there is a very good chance that NOS (New Old Stock) fuel hoses will not be compatible with the ethanol fuel most of us have to use. If you are running original fuel lines, or fuel hoses that have been on for a decade or two, you should change these fuel hoses before a disaster occurs. 

The Alfa Romeo GTV6 uses an electric fuel pump located under the car, tucked besides a chassis reinforcement at the right rear.  Fuel runs from the fuel tank to gravity feed the fuel pump (#10 in the image above) and then is sent to the fuel filter (#9) then makes a 180 degree turn to run towards the front fuel feed (#11) 

Sure, changing old fuel hoses is a good idea, but the problem is because of the convoluted routing of the GTV6's fuel hoses, there aren't many options available to service these GTV6 fuel lines. A couple of Alfa specialists make these special  fuel hoses with the 180 degree bend, but they are expensive, or may be out of stock and those that come from Europe may not be compatible with the fuel blends sold here.  

Ethanol fuel can cause issues in classic cars that were not made for the that type of fuel. Problems can include deteriorated rubber fuel lines, gaskets, and plastic and rubber fuel-system parts.

The work around many people do is try to bend a straight length of hose 180 degrees. This will likely to kink and restrict the fuel flow.  This could result in poor performance and premature fuel pump failure.  No Alfa GTV6 owner wants poor performance, so here's an option.

RetroMotion Innovations' Sidewinder U-Cut Molded Curved Fuel Line part number: RMI-33010 half-inch J30R7 (35 PSI)  fuel hose along with a Bosch fuel pump and stainless steel fuel barb connector.

Retro-Motion Sidewinde 1/2" Molded Fuel Line Rubber Hose

Stainless Steel 1/2" to 1/2" Hose Barb

I found a set of universal ethanol resistant fuel hoses made for custom applications with pre-formed 180 degree bends.  Manufactured by RetroMotion Innovations, their  Sidewinder U-Cut Molded Curved Fuel Line, features universal hose elbows with 45, 90, 135 and 180 degree curves. The company makes fuel lines in 3/16", 1/4", 5/16", 3/8", and 1/2" sizes.  

The Alfa GTV6 uses a 12.5 mm and 8 mm fuel hose.  Many in the US Alfa community use 1/2" for the 12mm and 5/16" for the 8 mm. 

Bosch 69412 OE Electric Fuel Pump

The Alfa GTV6 uses an electric fuel pump.  The original Bosch part number was 0 580 464 020, however, it is no longer available.  It has been replaced with this Bosch OEM replacement pump, part number 69412 ( 0 288 517 941 21).  This pump is capable of putting out 100psi, so it is important to use fuel injection pressure rated hose for the output and hoses downstream of the pump. It should also be ethanol compatible. The SAE standard to look for is J30R9 (100psi).  

The inlet to the fuel pump is 12.5mm, but a 1/2" (12.7mm) is deemed acceptable by many in the GTV6 community. The inlet or suction side of the fuel pump is gravity fed, so a J30R7 (35 PSI) spec fuel hose is what I used.  Getting a flexible J30R9 (100psi) spec, ethanol safe 1/2" fuel hose is difficult to source, plus the hose has to be flexible enough to be routed around chassis components. That may be difficult to do with a super stiff reinforced hose. 

Above you can see how I trimmed the inlet a little at a time to get the right fitment. There is not a lot of room to fit all these hoses in the fuel pump location, so to help,  I trimmed the inlet hose as tight as possible to the fuel pump. 

I suggest starting off trimming these fuel hoses a little long, so you can fine tune the fitment.  It is a  tight fit under the car, so I wound up trimming the inlet end as close as possible to the pump.  I used a  1/2" barbed fuel line connector and high quality European style clamps. The barbed end was super tight to push in, so a little P-80 Emulsion rubber lubricant made the fitting slide in super easy. 

HIGH PRESSURE J30R9 100PSI Sidewinder 5/16" RMI-33004 Rubber Fuel Hose

Once the fuel pump inlet side was done, I went to work on the fuel filter side. This hose has to be high pressure  J30R9 (100psi) spec hose.  The RetroMotion Innovations' Sidewinder 5/16 molded fuel line comes in J30R7 (35psi) or J30R9 (100psi) specs.  Make sure you get the high pressure 100psi hose! You'll also need a 5/16" barbed fuel hose connector and high pressure fuel injection spec hose clamps. 

Stainless Steel 5/16" to 5/16" Hose Barb

The trimmed fuel hoses. The small tube is the P-80 fuel hose lubricant that helps ease installing the tight fuel hose barbed ends.

The fuel hoses installed on the fuel pump and fuel filter.  

After the fuel pump and filter are clamped into their respected brackets, the large feed coming from the fuel tank (green arrow) is connected to the fuel pump barb.

The fuel pump feed line  (green arrow) come from the bottom of the tank, attached to the fuel tank filter screen. I used a fire and abrasion resistant silicone insulation sleave over the fuel feed hose. The red arrow is the fuel retune line coming from the fuel injection rail.  

Here's the GTV6's fuel tank screen and banjo fitting. The large 12.5mm / 1/2" fuel line is attached to this and feeds the fuel pump.

This is how I renewed my fuel hoses on my GTV6.  The information is provided for entertainment and informative purposes. At the very least, you'll get familiar with what's going on under the car.  Only you can decide if you feel comfortable doing this kind of work. Use the information at your own risk.  If you have any doubts on you ability to perform this work or have any issues, I recommend having it done by a professional. I am not responsible for any issues arriving from you reading this post. 

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Parts I Used On My Car For Your Convenience     

Retro-Motion Sidewinde 1/2" Molded Fuel Line Rubber Hose

HIGH PRESSURE J30R9 100PSI Sidewinder 5/16"RMI-33004 Mandrel-Formed Rubber Fuel Hose 90

P-80 Emulsion Temporary Rubber Assembly and Pump Seal Lubricant

I bought the above parts from Amazon (except the RMI-33004 which I couldn't find on Amazon). If you buy them from the Amazon link, as an Amazon Affiliate, I may get a tiny commission from the sale. If you do purchase them from the link, I thank you.

Alfa Romeo GTV6 Fuel Pump Hoses, Alfa Romeo GTV6 180 Degree Fuel Pump Hoses, Alfa Romeo GTV6 Fuel Pump Hose Routing, Alfa Romeo GTV6 Fuel Pump Hoses Diagram

Cleaning and Refinishing GTV6 Engine Parts

 

The Alfa Romeo GTV6 engine sports an aluminum alloy cylinder block and heads.  Pretty much all the external components of the engine are aluminum, with some magnesium alloy thrown in.  While many lightweight alloys are used in the engine, the Busso V6 is not lightweight, coming in at about 397 lbs*. This is due to robust internals like a forged steel nitrided crank, forged rods, cast iron cylinder liners, and case-hardened steel camshafts, among other stout components.

The Alfa GTV6's all-alloy engine is rugged and imposing. The upper and lower oil sump and bell housing are lightweight magnesium alloy.  The Alfa GTV6 set a record in the amount of magnesium used (about 99lbs.) in a road-going high production (over 10.000 units) automobile.**

The large two-piece magnesium oil sump holds nearly 8 quarts of oil.

 

Massive cam covers are a prominent feature of the Alfa GTV6 hemi-headed engine. This is my engine in 1997, just before installing it after a rebuild. 

And what the engine looks like now after being parked for the past 23 years.  Don't worry, we'll be taking care of that...

Cleaning the Alfa alloy engine presents some challenges.  One is aluminum can be easily damaged using the wrong chemical.  Even a handful of seconds in the wrong solution (like Purple Power / Alkaline chemicals) can discolor or even damage aluminum. Always read the instructions on these chemicals, and if it says dilute it, dilute it!  Be careful.

Another is what kind of finish do you want? Do you like the natural aluminum finish or the painted, blasted, plated, or coated look? It's your car, so do your research and enjoy whatever you choose. 

Alfa GTV6 Intake Tubes Clean Up

I like my engine's natural aluminum finish look, as long as it looks fresh and not old.  My intake tubes looked dingy even after cleaning (WD40 and brake clean).  I didn't want to paint them, so I thought of having them and other parts vapor-blasted / honed, but there were no facilities near me.  Just as well, as I'm not working with an unlimited budget.  

I've heard positive things about NAPA Aluminum Brightener and decided to try it. 

I taped off a section of an intake tube and tried it out.  You can see the results after about 30 seconds.  The aluminum intake tube was noticeably brighter. Wow, something that works!  

One note I'll make is to go slow with this product.   If you do multiple applications, limit the applying time to 30 seconds or so for each pass and then check the finish carefully.  Repeated applications can damage your part.  It is also a combination of phosphoric and sulfuric acid, so don't even think about not wearing skin and eye protection. Don't take a chance.

Alfa GTV6 Intake Plenum Clean Up and Paint

My intake plenum was next.  I cleaned it in a diluted Castrol Super Clean solution, leaving the surface discolored, grey, and dull.  I wouldn't recommend using Super Clean.

The intake plenum on a GTV6, being on top of the engine, is very noticeable, so I wanted it to look good but not be gaudy.  I was torn about what finish to go with, but I figured I would start with the natural aluminum finish and see how it looked.   Wondering how the NAPA Aluminum Brightener would deal with the discoloration. I applied three applications with the above results.  Not bad...

I then did the whole plenum to even out the finish.  I did multiple applications using a stiff plastic chemical brush.  Above is how it turned out.  There were still some patchy discolorations, but the surface was clean and as close to new-looking as I could get.  

While the plenum looked a lot better after the brightener treatments, I wasn't happy with the discoloration so I decided to see if I could match the factory color with an aluminum-colored engine paint. I tapped off the manifold to test how it looked, and it was an absolute surprise.

 I found it was identical to the natural color of the intake plenum. The mounting boss at the top was also painted and it is nearly impossible to tell where the paint starts or ends.  

I then gave the intake plenum a few light mist coats to blend in the discolored patches.  Looking at the plenum in person, it is hard to tell it was painted. 

Note that the roundish stain in the middle of the lower part of the plenum was from a yellow paint mark that has been there since I bought the car in 1986. I think the factory may put it there as a quality check mark.  I wanted to save the outline so I could re-paint it when I was done. It gives you an idea of how light the mist coats were.  

VHT SP955 Cast Coat Aluminum Engine Enamel paint  (Amazon Affiliate Link)***

 I highly recommend VHT SP955 Cast Coat Aluminum Engine Enamel paint if you are cleaning up your plenum and want the factory look.   A caveat is I know what it looks like with these mist coats, but if you do heavy coats, I can't speak to what they would look like.  

Alfa GTV6 Valve Cover Painting

The years were not kind to my GTV6's cam covers. These were originally painted with Kyrlon Dull Aluminum spray paint back in 1997. 

Washed up with a mild degreaser.  Whatever you use, check the warnings to ensure they don't mention Do Not Use on Aluminum.  Many common degreasers at auto parts or hardware stores are incompatible with aluminum. 

Degreased, cleaned, and sanded. Ready for paint.

Seymour Alumni-Blast Automotive Aluminum Spray Paint (Amazon Affiliate Link)***

I painted the valve covers with Seymour Alumni-Blast Automotive Aluminum Spray Paint. 

I used a red permanent paint marker to paint the Alfa Romeo script.

Take your time doing this.  It's good to practice on something to get the feel of how the paint flows.

Done and ready to install. 

I'm not 100% with the look, but the Alumni-Blast is a popular paint, and the covers look much better. I may revisit them at a later date.

Painting the Alfa GTV6 Intake Plenum, Painting the Alfa GTV6 Valve Covers

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* Road&Track 1982 Alfa Romeo GTV6 Road Test.  Alfa V6 engine weights have been reported between approximately 330 lbs to 400 lbs and up. The 397lbs. listed in the post above ia from a period Road Test and from a credible source.

**Source:  Proceedings of the 39th World Magnesium Conference and Exhibition, 13-15 June 1982, Detroit, MI, USA, pp. 57-60

***   I spend hours doing research trying to find products I can use for my car.  To save you time and the aggravation finding something that works for your car, I participant in the Amazon Services LLC Associates Program.  The links posted are the products I've used, plus as an Amazon Associate I can possibly earn something from readers making qualifying purchases.  Links to products may earn this site a tiny commission if purchased. 

1981 Alfa GTV6 Dealer Press Release Intro

 

The Alfa Romeo GTV6 was introduced to the United States in the 1981 model year. Posted here is the 1981 Alfa Romeo GTV-6/2.5 Coupe press release information kit featuring Mario Andretti. These kits were produced for the approximately 141 Alfa Romeo dealers in the USA back in 1981 to get them up to speed on the new GTV6 model.

In 1979, Alfa Romeo returned to Formula 1 racing after a 28-year absence. Mario Andretti signed on to be a team driver in the 1981 season. The well-known Andretti, a beloved racer in the US with celebrity status, was the perfect spokesman for the hottest Alfa Romeo ever brought into the country.

How much Formula 1 racing technology filtered down into the new GTV6 sounds like hyperbole, but it makes for good copy.   

The EPA estimated the 1981 GTV/6 highway mpg to be 28 mpg. In my experience, this was an accurate estimate, as I commonly achieved that in my car on the highway. 

The 1981 Alfa GTV6's manufacturer-suggested list price was $16,983 plus destination charge, dealer prep, and any optional extras.

Estimating typical destination charges of the day at $260, dealer prep at $140, and a four-speaker stereo at $350, you get a total of $17,733.  

The press kit included this Autoweek article to whet the appetite of the dealer body. The GTV6 was eagerly anticipated not only by dealers but also by the US press.

1981 Alfa Romeo GTV6 Brochure

Alfa Romeo GTV6 Transmission Ratios

 The Alfa Romeo GTV6 transmission gear ratios have been revised a few times during its production life. Using official factory resource materials, here's a look at the various gear ratios used. Before we do, like many things that concern the GTV6, production changes overlap model years. For example, my car is a 1982 model year but has the 1981 transmission ratios. So don't be surprised if a 1984 car has 1983 gear ratios, etc. Typical Alfa.

When the car debuted in Europe in 1980, the ratios were as follows.

Alfa Romeo GTV6 Transmission Ratios (European and Early US Cars)

ALFA GTV6 EURO AND EARLY US TRANSMISSION GEAR RATIOS

Final Drive: 4.10:1

(gear ratio / overall ger ratio)

1st: 3.50:1 / 14.350:1 

2nd: 1.956:1 / 8.0196:1 

3rd:  1.345:1 / 5.5145:1 

4th:  1.026:1 / 4.2066:1

5th: 0.78:1 / / 3.198:1   

REV. 3.000 1 / 12.3000

European and Early US Spec Alfa Romeo GTV6 Speeds in Gear*

1st   @1000rpm  4.8mph (7.803kmh)               @6300rpm  30.55 mph (49.16 kmh)

2nd  @1000rpm   8.67 mph (13.964 kmh)        @63000rpm  54.66 mph (87.97 kmh)

3rd  @1000rpm    12.63 mph (20.321kmh)       @63000rpm   79.55 mph (128.02 kmh)

4th   @1000rpm    16.55 mph (26.642 kmh)      @6300rpm   104.29 mph (167.85 kmh)

5th   @1000rpm  21.78 mph (35.053 kmh)        @6300rpm 137.22 mph (220.83 kmh)

RPM @ 60 mph in 5th gear: 2755 rpm 

These were the same ratios used in North America when the GTV6 hit our shores in 1981. Some early 1982 GTV6 models also had these ratios until they were replaced by the noticeably taller ones below.

Alfa Romeo GTV6 Transmission Ratios (1982-1983 US Spec)

1982-1983 ALFA GTV6 TRANSMISSION GEAR RATIOS

Final Drive:  3.42:1

1st  3.500: 1 / 11.958:1

 2nd 1.956: 1 / 6.683: 1

3rd  1.258: 1 /4.298 1

4th  0.946: 1 / 3.232: 1

5th  0.780: 1 / 2.665: 1

REV. 3.000 1 / 10.249: 1

1982-83 US Spec Alfa Romeo GTV6 Speeds in Gear**

1st   @1000rpm  5.82 mph (9.37 kmh)              @6300rpm  36.68 mph (59.03 kmh)

2nd  @1000rpm   10.41 mph (16.76 kmh)        @63000rpm  65.61 mph (105.59 kmh)

3rd  @1000rpm    16.20 mph (26.07 kmh)       @63000rpm   102.06 mph (164.24 kmh)

4th   @1000rpm    21.54 mph (34.66 kmh)      @6300rpm   135.68 mph (218.36 kmh)

5th   @1000rpm  26.10 mph (42.00 kmh)        @6300rpm 164.41 mph (264.60 kmh)

RPM @ 60 mph in 5th gear: 2299 rpm

Some feel that these taller ratios took away the "hot-rod" feel of the earlier car. However, the lower rpms at highway speed were welcomed by many who spent a lot of time on the highway. First gear also became more useful. Zero to sixty times were also improved by eliminating the shift out of second gear before sixty miles per hour were reached.

Alfa Romeo GTV6 Transmission Ratios (1984-85 US Spec and Other Markets)

These ratios continued until the 1984 model year, when the 1982 tall gear ratios were combined with the original 4:10:1 final drive. This transmission is referred to in Alfa Romeo documentation as the "High-Geared Gearbox/Differential." 

1984-1985 ALFA GTV6 TRANSMISSION GEAR RATIOS

Final Drive: 4.10:1

1st 3.500:1 / 14.350:1 

2nd 1.956:1 / 8.0196:1

3rd 1.258:1 /  5.1578:1

4th 0.946:1 /  3.8786:1 

5th 0.780:1 / 3.198:1 

1984-85 US Spec Alfa Romeo GTV6 Speeds in Gear*

1st   @1000rpm  4.84 mph (7.80 kmh)              @6300rpm  30.53 mph (49.14 kmh)

2nd  @1000rpm   8.67 mph (13.96 kmh)        @63000rpm  54.65 mph (87.95 kmh)

3rd  @1000rpm    13.50 mph (21.73 kmh)       @63000rpm   85.07 mph (136.90 kmh)

4th   @1000rpm    17.95 mph (28.89 kmh)      @6300rpm   113.10 mph (182.01 kmh)

5th   @1000rpm  21.78 mph (35.05 kmh)        @6300rpm 137.21 mph (220.82 kmh)

RPM @ 60 mph in 5th gear: 2755 rpm

Note: These speeds are based on 195 60 R15 tires for comparison sake and not the TRX Metric  200/60 HR365  tires size standard on the 1985 US GTV6.

Interestingly, while most European cars I've heard of stayed with the original 1980 gear ratios, this "High-Geared Gearbox/Differential" is listed in the European Technical Inspection Manual dated from 3/1984. 

1985.5 ALFA GTV6 Isostatic Gear Shift

 Starting about mid-way through the 1985 model year for US cars (Chassis number 10006731 according to Alfa Romeo documentation), Alfa updated the transmission shift linkage for an improved feel. This revised shift linkage is commonly called "Isostatic ." This modification replaced the simple external shift lever at the transmission case with a series of rods and levers. The consensus at the time was that the revised shifter was smoother, easier, and had a more positive feeling than the rather clunky original shifters. However, nearly 40 years later, Isostatic shifter parts are challenging to source. Because of that, some are saying if you have a worn-out shifter, you are better off now with the old-style shifter mechanism. So much for doing the Isostatic upgrade I never got around to doing!

Update 2-21-2023

I see the Alfa Romeo European Workshop Manual showing 1985 and later European GTV6 models as having the ratios listed below. I invite our European friends to post a comment and let us know what ratios they have in their cars.

Alfa Romeo GTV6 Transmission Ratios (1986 US Spec and late 1985 European Version)

The gear ratios were revised again in 1986. The 4.10:1 final drive was retained, but the first three gears were modified. This close ratio gearbox had less of a gear spread, which is intended to keep the engine in its powerband while accelerating. Now the first four gears were closer without the significant speed gaps of the 84-85 transmission. First gear also returned to being a more useful gear ratio, which many people welcomed. 

1986 ALFA GTV6 TRANSMISSION GEAR RATIOS

Final Drive: 4.10:1

1st 2.875: 1 / 11.787:1

2nd 1.720: 1 / 7.052:1

3rd 1.226 1 / 5.027:1

4th 0.946 1 / 3.879:1

5th 0.780:1 / 3.198:1

REV.  3.000 1 / 12.300:1

1986 US Spec and late 1985 European Version Alfa Romeo GTV6 Speeds in Gear*

1st   @1000rpm  6.00 mph (9.646 kmh)              @6300rpm  37.76 mph (60.770 kmh)

2nd  @1000rpm   10.01 mph (16.123 kmh)        @63000rpm  63.12 mph (101.575 kmh)

3rd  @1000rpm    14.05 mph (22.620 kmh)       @63000rpm   88.55 mph (142.506 kmh)

4th   @1000rpm    18.21 mph (29.315 kmh)      @6300rpm   114.76 mph (184.685 kmh)

5th   @1000rpm  22.08 mph (35.553 kmh)        @6300rpm 139.18 mph (223.984 kmh)

RPM @ 60 mph in 5th gear: 2716 rpm

Update 2-19-2023:

I have found official speeds in gear@1000 rpm and have updated the 1986 numbers. Previously they were calculated.

Let us know if you have more information to share by leaving a comment.  Thanks for reading!

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Sources: 

Alfa Romeo Inspection Specifications publications dated 10/1981, 2/1981, 3/1984, 

Alfa Romeo GTV6 Owners Manuals: 1981 through 1986

Alfa GTV6 Spare Parts Catalog, USA edition 0060495165, 9-1989

Alfa Romeo Workshop Manual  PA36090+ 9/84

*Official km/h @ 1000 RPM speeds in gear provided by factory. Converted to mph for convenience.

**Approximate speeds in gear calculated. Factory tire size value used. Rolling radius of tires, among other variables, affects speed. Speeds are rounded for convenience.