Replacing entire fuel system

It's next to the carb.

Well - the investigation was taxing -- but the result was a pretty easy solution. Turns out the output of the Mustang/Ford fuel pump relay was providing the power input to fuse #5. As I traced the wire from the relay (underhood) back into the car -- it was connected to a 'new' wire that ran to the backside of fuse #5. I recall having to cut this wire when I pulled the motor (and computer) -- because I put a male/female plug in to make disconnection easier the next time. Didn't know what it did or what it was -- just knew I needed to reconnect it. So all I had to do was unplug it from the power-supply/backside of fuse #5 at the fuse box -- and plug it into the new relay. Now power supply comes into the relay through fuse 7. It's triggered by the output of the Ford FP relay -- and it sends power to both of the original Volvo fuel pump wires, which if you've been following along, are now connected through the original plug in the trunk to the new fuel pump. According to the test light - it's working as it should. Primes for about a second with 'key-on'. Primes as long as it's turning over at more than 120 rpm. Should keep running when the engine starts.

Here I've pulled the 3 wires needed out of the Volvo relay plug - red is the power supply from fuse #7; black is ground for the relay coil; and the 2 yellow/red wires head back to the fuel pump.



Here I've rigged up the new relay with a jumper to simulate the signal input from the Ford relay. Sure enough -- I get power at the pump plug at the back, as I should.



Here I've put some shrink wrap around the plugs --- just a bit of help so that something hot is less likely to touch something it shouldn't when plugs are being pulled on/off.



And here - I decided to leave the Volvo fp relay/plug in place and just taped the new relay to it. (thanks Sean) I've got the 'trigger' wire from the Ford relay hooked up (green wire). Everything is all buttoned up after testing. Can't do any more now until my hoses come back from Fragola Perf. Systems. Turns out it's VERY difficult to make up the -6AN hose ends. The interference fit is extremely tight - and despite coaching from the folks at Fragola, use of boiling water and/or a heat gun to heat the hose (Fragola recommended this as they do it this way) I was never able to get a hose past the first barb. And it must go completely over two. So I mocked everything up, cut the Series 8000 hose to length -- and sent the hoses/ends to the good folks at Fragola who will make them up for me and ship them back. I'm ready. I've got a pump to test!!!

Brint and the fine folks at Fragola Performance Systems received my hoses/fittings on Tues and had them on the way back to me Wed. I got them today!!!



I was able to pretty quickly get the shortest one (8") installed -- from the supply bulkhead fitting to the filter inlet.



The other two are 10' (supply) and 13' (return) long and have multiple hangers along the way. I don't want to start that until I can finish it. My wife had oral surgery this morning (metal implant screwed into the lower jawbone!) so I'm in nursing mode this evening. And it's Friday the 13th anyhow -- I'll try and get it running tomorrow!!

Well - got the hoses in today -- everything hooked up and tightened. Still have a small heat shield to build for the passenger side cat -- and then I can start the car. In the morning I'll take a stab at jumpering the pump and see if we have any leaks.

Both lines hooked up at the back. Line on the left (driver's side) is the return - it follows the same path/hangers that the stock supply line was in.



Here's the return line exiting through the little hole in the Panhard support and headed to the front of the car.



Here's the supply line (passenger side) leaving the filter and running to the front. I put new rubber lined clamps all the way to the front --- basically the same route as the original supply line, but on the passenger side of the car.



Here's the termination point up front. Simple barbed fittings to connect to the Ford supply and return lines. All of this will be hidden by the 'splash' pan.



And here's a broader shot from up front -- you can see (sort of) how the return line comes up and crosses under the engine.



Now I have 3/8" (-6AN) fittings right up front so if new powerplants require more fuel, the system should have no problem delivering it. And plumbing it up can all be done with a bit of work at the front of the car.

First success this afternoon!!! I put the battery on the charger -- and jumpered the hot side of the pump plug. This allowed me to easily test the pump by turning my ground disconnect switch off and on. Pump fired right up -- and miracle of miracle -- not one leak. Pump sounded fine (quiet!) and you could hear it push the air out of the system as it gurgled through the return into the tank. Put the pressure gauge on it -- and it came right in at about 41 psig. That's on the high side -- 39 psig is preferred so I'll check that at warm idle once I've got 'er down off the stands and running again.

Here's a pic of the jumpered plug....



I crawled underneath to try and take a few pics of the heat shields around the cats, as well as the general routing of the lines. But it's tough without the car on a lift. (must get lift....getting too old) So the next few shots just show a bit of the routing. First one shows how the return line snakes past the rear brake line proportioning valves; next couple show some of the heat shields; and perhaps the last one is with the trunk finally back together.









So - with any luck tomorrow I'll get it back on the ground and see if she'll start. No reason to think that will pose a problem as I have pressure where I should; I know the pump is circulating fine; and my electrical checks seem to be showing that the relay circuit is working as it should. Then on to mounting a new set of wheels and tires.

Good deal. Glad you are doing it the right way.
I hadn't thought about extending the inline pump supply wires to the rear like that. I'll definitely do that when I convert to a single pump!

Looks like your whiteblock conversion is coming along nicely. Ultimately, I want to LS3 mine - and this fuel system will manage that quite nicely. I also wanted the space to put two mufflers in front of the rear axle -- so the inline pump had to go. Am intrigued by your muffler fab --- I've often wanted to make my own and may yet give it a go.

M.H. Yount said:

The Ford engine has supply/return connections on the front/passenger side of the compartment.

Click to expand...

Do these connections point down towards the ground? Just wondering why you didn't bring the feed line up the firewall and across to the engine instead of routing under crossmember and up from the bottom of engine.

pwschuh said:

Do these connections point down towards the ground? Just wondering why you didn't bring the feed line up the firewall and across to the engine instead of routing under crossmember and up from the bottom of engine.

Click to expand...

Just saw this, it seems a bit risky exposing the line on the forward most point under the car.

"Just wondering why you didn't bring the feed line up the firewall and across to the engine..."

Because the connections to the Ford system are at the bottom of the engine (yes -- pointing down towards the ground) under the alternator and air injection pump on the passenger side front of the engine. They sit about 2" away from the downward 'dip' the front V6 sway bar takes to clear the balancer. The connections to the system previously came via two 6' long rubber efi hoses from the stock Volvo filter/return line high on the firewall on the driver's side running alongside the driver's side framerail (in close proximity to the steering shaft and the driver's side exhaust manifold). This change was, in part, to get rid of that routing which was terrible given the location of the stock rails on the Ford motor. Not only did the new routing remove about 6' of fuel line from the supply route and 3' of line from the return route (both of which reduce risk) - it removed about 12' of rubber fuel line (supply and return) from the ravages of engine compartment heat. And I was very careful to keep it higher than all the hard parts (oil pan bottom, bottom of bell housing, lower braces/suspension arms, front 'frame rails', front sway bar....). If I have a big enough excursion to damage the fuel lines -- I will have run into (literally) much bigger problems than that.

A big part of the reason for going this route is that when the time comes to swap the Ford lump for an LS lump -- I can very easily modify this new 3/8" system to deliver fuel exactly where it's needed. In the case of the LS with a car manifold it's right at the top/rear of the intake manifold. And in the meantime -- I have much less fuel line (and MUCH more robust) in the system than I did before subject to much less heat than it was before. So I'm pretty sure I'm better off in all respects than before. I did give it a good bit of thought before jumping in.... And yes -- I wish the connections to the Ford system were on the driver's side, high near the back of the engine. But they didn't ask me.

A footnote -- unless you've played with V8 conversions - you're probably unaware of just how tiny the real estate is you have to work with running anything from below up the firewall. On both sides you now have exhaust manifold joints that are nearly right up against the frame rail. I'll take advantage of the engine being out of the car when I do the LS conversion to make choices on fuel line routing and exhaust manifolds so that I minimize the interference between the two.

I jumpered the pump again and set the fuel pressure to 39 psig. Took it off the jack stands and turned the key. She fired up on the first try. Settled into a nice 800 rpm idle -- 19" of vacuum brought the fuel pressure down to 30 psig at idle. I thought it was quiet standing at the back of the car with the trunk open - but you can't even hear the pump prime from inside the car anymore. You certainly can't hear it with the motor running. Took it around the neighborhood long enough to bring the cooling fans on and the oil temp up to 180F. Very uneventful. No pressure venting out of the fuel cap. Fuses/wires/connectors all cool to the touch. No leaks of liquid or 'smoke'. Should be good for a 200 mile run down to the Walter Mitty vintage races at Road Atlanta weekend after next.

And I test fit my new Voxx 17x8's. All went well. Man does the wheel ever sit close to the strut....but not much moves around up there. 1/4" is as good as a skosh.

I'm calling this one a success. Only thing left to do is let it run for 3 or 4 hours on a long cruise. But I suspect that will be as uneventful as the trip around the neighborhood was.

Thanks for the tips/help/questions.

Great. Doing it right the first time definitely saves some headaches later.

Well, well, well - not so fast. Car starts, runs absolutely great. Can't hear the pump at all -- couldn't be happier with all that.

Problem is this -- I smell fuel fumes in the garage. There are no leaks at fittings or hoses. As I research this -- it seems it's quite a common problem for folks that use SS or textile braid hose. It has it's roots in the fact that usually none of these hoses (with rubber-based cores) are rated SAE30R9 for fuel use (or better rating). I believe that the problem is that with ethanol in the fuel the molecules of certain components of the fuel literally come through the hose. LOTS of people face this problem it seems. And all are upset about it as many have spent literally hundreds of dollars on stainless braided hose only to have it stinking up the joint. No danger apparently - but a pain in the butt if you have a car that sits in a closed garage for any length of time. Luckily, the garage the Volvo lives in is detached; some folks are actually getting fuel fumes inside their houses!

So far the supplier (Fragola) hasn't returned my email asking questions about the problem. I'll try again next week and also bring Summit into the picture as I actually bought everything through them. In the meantime I found a Ferrari guy out on the west coast who has had some success by putting polyolefin shrink tubing around the fuel line. For about $25 I can try that and see - before I give up and bend hard aluminum lines. Knowing the routing as I now do intimately, it turns out the hard lines won't be so bad if I have to go that route. I only need a 'bender' for one tighter radius turn on the return line at the front of the car. All the rest I can simply 'shape' by hand.

Everything, it seems, is a production.

Word to the wise -- before you lay out a bunch of green for this type hose do your research. Hard lines may be a better (certainly less expensive) to go. FWIW -- the folks that have SS braided lines with a teflon core don't seem to have this problem. Moral of the story is - you can buy fuel line that is hell-for-stout when it comes to dealing with heat, pressure and abrasion. But it won't stop tiny little hydrocarbon molecules from passing right through it unless it was designed to do just that.

Found a place where I can get 25' of polyolefin shrink tube for $19. Gonna try that and then cover it with a silicone stretch tape and see if those barriers solve the problem. Stay tuned. Although -- it's getting boring even for me at this point. I've got new wheels to sand and paint...

M.H. Yount said:

Well, well, well - not so fast. Car starts, runs absolutely great. Can't hear the pump at all -- could be happier with all that.

Problem is this -- I smell fuel fumes in the garage. There are no leaks at fittings or hoses. As I research this -- it seems it's quite a common problem for folks that use SS or textile braid hose. It has it's roots in the fact that usually none of these hoses (with rubber-based cores) are rated SAE30R9 for fuel use (or better rating). I believe that the problem is that with ethanol in the fuel the molecules of certain components of the fuel literally come through the hose. LOTS of people face this problem it seems. And all are upset about it as many have spent literally hundreds of dollars on stainless braided hose only to have it stinking up the joint. No danger apparently - but a pain in the butt if you have a car that sits in a closed garage for any length of time. Luckily, the garage the Volvo lives in is detached; some folks are actually getting fuel fumes inside their houses!

So far the supplier (Fragola) hasn't returned my email asking questions about the problem. I'll try again next week and also bring Summit into the picture as I actually bought everything through them. In the meantime I found a Ferrari guy out on the west coast who has had some success by putting polyolefin shrink tubing around the fuel line. For about $25 I can try that and see - before I give up and bend hard aluminum lines. Knowing the routing as I now do intimately, it turns out the hard lines won't be so bad if I have to go that route. I only need a 'bender' for one tighter radius turn on the return line at the front of the car. All the rest I can simply 'shape' by hand.

Everything, it seems, is a production.

Word to the wise -- before you lay out a bunch of green for this type hose do your research. Hard lines may be a better (certainly less expensive) to go. FWIW -- the folks that have SS braided lines with a teflon core don't seem to have this problem. Moral of the story is - you can buy fuel line that is hell-for-stout when it comes to dealing with heat, pressure and abrasion. But it won't stop tiny little hydrocarbon molecules from passing right through it unless it was designed to do just that.

Found a place where I can get 25' of polyolefin shrink tube for $19. Gonna try that and then cover it with a silicone stretch tape and see if those barriers solve the problem. Stay tuned. Although -- it's getting boring even for me at this point. I've got new wheels to sand and paint...

Click to expand...

Bumping the thread I know.
If you do go the heatshrink route. Search out Raychem DR-25. Its the diesel resistant type so it'll be happy around fuel. Not cheap though.

Car's been running so good and so much fun to drive I've been delaying taking it down to heat shrink the lines! But I finally did today. Pulled 'em off and have 'em hanging in front of a fan to dry them out. Confirmed -- you can definitely smell gasoline outside the hose when you put your nose on it. I'm going to try a relatively low buck fix -- silicone stretch wrap tape and then the polyolefin shrink-wrap (3:1) over it. If that doesn't do it - I'll just hard line it with aluminum tubing. The RayChem is $464 for 50'. I don't have that in the whole fuel system - pump, line, fittings, etc. LOL Besides, it's only available in a 2:1 reduction - and that won't git 'r done. Need 1" to fit over the fittings - and need 3:1 reduction to cinch things up.

Lines came off easily and the silicone tape and heatshrink went on beautifully. Should get it running tomorrow and we'll see if the aroma of gasoline is a distant memory.

looks good!!! you coming to the NC meet????
if so, do you still have that old kjet pump laying around???

awesome.

No - won't make it up on Sunday. I didn't get it all the way back together today. The silicone wrap and heat shrink increased the diameter just enough that my insulated clamps don't fit; so I've got to do some reconfiguring. And I've got to change my speedo gear as well - easy while it's up in the air. HOPING I get the gear/new o-ring in the mail tomorrow. Don't have my old pumps -- I donated them to a buddy with a Nissan SR20 turbo motor in a 510 Datsun.

Early - but it appears we have success!!! I primed the pump yesterday -- and 18 hours later - no gasoline smell in the garage. When I first primed - I had the smell of gasoline 8 hours later. If it changes I'll post again.