Light fuel leak at the fuel distributor

[FPBBrandon]

I got my car home last night, and thought I smelled gas in the garage when I put it away.

I poked around this morning to find a pinhole leak coming from one of the banjo bolts for the fuel lines into the fuel distributor.

My question is can I disconnect the line from the car to try replacing the sealing washers easily? I'm not sure how much pressure is sitting in the line, or any other gotchas in working with the lines.

Any advice? I checked the FAQ and How-to and didn't see much there that pertained to distributor.

[Ron]

There is enough pressure that you might loose an ounce or so of fuel if you don't wait a few hours. I'd use a rag to catch it if I just couldn't wait...use new washers if possible.

[FPBBrandon]

There is enough pressure that you might loose an ounce or so of fuel if you don't wait a few hours. I'd use a rag to catch it if I just couldn't wait...use new washers if possible.

Thanks much. Can I source the washers locally (i.e. would they cross from other K-jet cars?)

[sdg3205]

Thanks much. Can I source the washers locally (i.e. would they cross from other K-jet cars?)

Ive ordered them through volvo dealers. There is a wait sometimes.

[jawn101]

The washers are surprisingly hard to find. I would have thought enough K-Jet was out there in the world to make them common, but the last time I tried to buy them the guy tried to convince me a small fender washer was the same thing :dunno:

[Ron]

Thanks much. Can I source the washers locally (i.e. would they cross from other K-jet cars?)I get them from my local ACE. Take an old one with you because they carry two that are very close to the same size for injector banjos (match the ID)...they have most of the others and if not, I get them from DMCMW (Dave or Julee). (Order extras ;-)

[DeLorean03]

You are VERY fortunate to have caught this in your garage, and you're subject to a miracle if you drove the car home with that leak. We have had a scary spike of engine fires lately, and fuel leaks are suspected to be easily the #1 cause of them. Call DMCMW (Dave and Julee), get new washers. Get a full set for everything on the distributor (18 small ones for the fuel lines and 3 big ones for the "bigger lines" on the side and back of the FD) as well as washers (2) for the cold start valve (CSV) and for the CPR/WUR (4) (control pressure regulator/warm up regulator).

This is not an area of the car you want to be questionnable or luke-warm about.

The banjo bolts should be a 12mm. Have a shoprag (red rag) ready underneath your wrench to catch any fuel that comes out. If you're going to wait a day or two, very minimal fuel come out, but expect a few drops easily - even after a day or two.

[Mark D]

Do banjo bolts really just start leaking out of nowhere like this? It seems really unlikely that suddenly a fitting would loosen up or a copper washer would fail.

If I had to guess a failure point I'd expect that the hose itself has a small leak and it's just dripping down onto the banjo bolt giving you the impression that the fitting/copper washer is leaking.

The fuel injector hoses are somewhat deceiving because of how they are constructed. The inner diameter is much smaller than you realize and there is a thick outer rubber cover over the thermoplastic inner hose. The plastic portion of the hose gets brittle and will develop hairline cracks causing fuel to leak but with no visible damage from the outside. The rubber protects the plastic hose but also covers up any cracks. Eventually the pressurized fuel will be able to find it's way between the layers of the hose and start to cause visible leaks.

The top of my fuel distributor was consistantly wet with fuel but all fittings were tight... leading me to suspect the hoses. It wasn't until I carefully cut back the rubber outer hose cover that I was able to find where the inner hose had failed.

Even if your banjo fittings/copper washers ARE the culprit in this case I would still recommend replacing the stock fuel hoses. If they are not leaking now they could end up failing as a result of flexing the hoses around as you go through and replace the copper washers. The SS braided fuel line kits are cheap compared to fire damage.

[OverlandMan]

+1 to what others have said about you dodging a real problem so far. I had a small engine fire a month ago that still has my car off the road. I was lucky in that I caught it before any real damage was done. Others have had their car completely lost. I'm in the process of gathering up all the necessary parts to rebuild the k-jet part of the fuel system.

I'd recommend you doing this as well before you drive the car any more.

[FPBBrandon]

I got at it last night, and did some investigating. The sealing washer on the high side of the banjo bolt has a small straight channel in it (that I can see and feel with a fingernail) thats letting the fuel squirt out under pressure. The banjo head itself looks like its a little rounded off compared to the other 5 on the distributor. The car will be off the road until this gets cleared up.

I think new sealing washers and a banjo bolt for the line will hopefully do the trick to get rid of this particular line's issue. I'm considering doing all 6, but as mentioned above I'm not sure I want to run the risk of tweaking the old lines unnecessarily until I have replacement lines in hand ready to change. As far as I can tell from everything I looked at last night, this is the only fuel leak I have.

[DeLorean03]

Get new stainless steel braided fuel lines. Have had mine 10 years nearly - not one single issue. Very strong and durable - they are WELL worth their price of admission at DMCMW or SpecialTAuto.

[FPBBrandon]

Get new stainless steel braided fuel lines. Have had mine 10 years nearly - not one single issue. Very strong and durable - they are WELL worth their price of admission at DMCMW or SpecialTAuto.

Installation of the lines involves pulling the body off the frame, doesn't it?

[opethmike]

Installation of the lines involves pulling the body off the frame, doesn't it?

No. The hoses Jeremiah is talking about are replacements for the rubber hoses that attach to the distributor.

[DeLorean03]

No. The hoses Jeremiah is talking about are replacements for the rubber hoses that attach to the distributor.

Correct.

Quick picture reference:

22806

[FPBBrandon]

A new banjo bolt and a few crush washers cleared the leak up. Haglin automotive in boulder had actual delorean parts on hand and were awesome in terms of getting the parts to me quickly.

My garage doesn't smell like a gas station anymore!

[DeLorean03]

Excellent - glad you got that taken care of.

I'm not trying to spend your money, promise, but consider investing in the SS fuel lines when you can. We've seen too many fires this year, and some members here can attest to the weakness of over a 1/4 century old flexible lines.

Just to think, when those lines were installed in the car, the Berlin Wall was up, CDs were non-existant, Microsoft hadn't introduced Windows 3.1, and Nintendo hadn't introduced the NES.

Take it for what it's worth :thankyou:.

[FPBBrandon]

Excellent - glad you got that taken care of.

I'm not trying to spend your money, promise, but consider investing in the SS fuel lines when you can. We've seen too many fires this year, and some members here can attest to the weakness of over a 1/4 century old flexible lines.

Just to think, when those lines were installed in the car, the Berlin Wall was up, CDs were non-existant, Microsoft hadn't introduced Windows 3.1, and Nintendo hadn't introduced the NES.

Take it for what it's worth :thankyou:.


Totally understood, I plan to do new lines (though the comparison to the various things this car and its fuel lines have been around for had me laughing pretty hard). I just need to recover a bit from buying the car first! I addressed some other things last night, like the unsprung horn. Going to try to tackle the constant-on ebrake light tonight. I love it so far!

[Jack]

I've seen on or two owners with hard/metal fuel lines.
They look pretty much like brake lines.
Anyone have any info on that set up?

[DeLorean03]

Totally understood, I plan to do new lines (though the comparison to the various things this car and its fuel lines have been around for had me laughing pretty hard). I just need to recover a bit from buying the car first! I addressed some other things last night, like the unsprung horn. Going to try to tackle the constant-on ebrake light tonight. I love it so far!

Totally understand, my friend :thumbup:. I just didn't want it to fall in the perpetual "one day...." spiral and then somewhere down the road a tiny fuel leak become an engine-consuming fire :bawling:.

Glad you got one of these cars! Believe me, life will never be the same :P.

[David T]

Totally understand, my friend :thumbup:. I just didn't want it to fall in the perpetual "one day...." spiral and then somewhere down the road a tiny fuel leak become an engine-consuming fire :bawling:.

Glad you got one of these cars! Believe me, life will never be the same :P.

In my experience it is rare to see the fuel lines (the lines themselves NOT the connections) around the motor leak. Unless they were abused (kinked, stretched, twisted, overheated) they seem to be very safe. The crush washer with the scratch is troubling. It sounds like it was reused and it is not safe to reuse them in most circumstances. If there are no other leaks, then things are best left alone once the known leak is fixed. Hard lines make it harder to work on the car and they have to be bent exactly or you put stresses on the parts. Typically what happens when you reuse the copper washers is that they get work-hardened from the first use and when you go to reuse them they won't "give" because they are no longer soft. You get a leak so you try tightening the banjo bolt more to stop the leak. When you overtighten the banjo bolt you break it, it is weak in the middle and not meant to be made so tight. Probably why the one you see is rounded over, from being overtightened to try to stop the leak. Very common for a newbie to lose a washer and not know it, have a leak and break the bolt in the hopeless attempt to stop the leak. Fuel leaks on a K-jet system are particularly dangerous because of the higher than usual pressures. With such high pressures you may not even see a leak or wetness because the fuel is instantly vaporized. A spark or enough heat and you have a jet of flame. You are fortunate to have found the leak and not have had any problems.

[FPBBrandon]

In my experience it is rare to see the fuel lines (the lines themselves NOT the connections) around the motor leak. Unless they were abused (kinked, stretched, twisted, overheated) they seem to be very safe. The crush washer with the scratch is troubling. It sounds like it was reused and it is not safe to reuse them in most circumstances. If there are no other leaks, then things are best left alone once the known leak is fixed. Hard lines make it harder to work on the car and they have to be bent exactly or you put stresses on the parts. Typically what happens when you reuse the copper washers is that they get work-hardened from the first use and when you go to reuse them they won't "give" because they are no longer soft. You get a leak so you try tightening the banjo bolt more to stop the leak. When you overtighten the banjo bolt you break it, it is weak in the middle and not meant to be made so tight. Probably why the one you see is rounded over, from being overtightened to try to stop the leak. Very common for a newbie to lose a washer and not know it, have a leak and break the bolt in the hopeless attempt to stop the leak. Fuel leaks on a K-jet system are particularly dangerous because of the higher than usual pressures. With such high pressures you may not even see a leak or wetness because the fuel is instantly vaporized. A spark or enough heat and you have a jet of flame. You are fortunate to have found the leak and not have had any problems.

Agreed. I'll keep smelling for gas and checking under the hood, but the immediate threat is out of the way.

[DeLorean03]

I don't trust the integrity of the seal between the fuel line and the banjo bolts. Even our vendors say the fuel lines from the factory are prone to cracking. The stainless lines are smaller, allow more more to work, are almost 3 decades newer, more resistant to failure, can be bent nearly on top of themselves (ask me how I know), are a welcome upgrade visually, and offer a great peace of mind. The banjo bolt connections on the original lines are an absolute joke. In my early days of owning my car, I cracked a fuel line just trying to loosen the line that meets the CSV. It was ridiculous. Many owners have upgraded the lines, and there's a reason nearly all vendors have started offering these.

I am not saying an owner is negligent if they keep the original lines. They want to do that, that's fine.

Bottom line, yes, if the fuel lines are never, ever messed with - then I am sure all will be fine. But we all know sooner or later, those lines are coming off for one reason or another. When they do, I wouldn't be putting on 32 year old fuel lines. I don't trust those plastic lines - especially with gasohol running through them.

[David T]

The vendors stock and sell stuff that they know their customers will buy. Just because you can buy them is not a good reason to replace the lines. The interior is not plastic, it is much tougher than plastic (I don't know exactly what it is but it isn't plastic or rubber). I do not want Delorean owners to think the lines are a time bomb, ready to explode and burn the car to a crisp. It is not that bad unless the lines were abused and you would know it because they WOULD be leaking. The fuel lines I would be careful about are the ones by the fuel pump. In the beginning people were changing their fuel lines on the motor because they wanted the "look", not for any safety reasons. That is why the vendors started providing them. If you feel you need to change lines, change the clutch line and the 4 brake hoses and the one from the clutch reservoir to the master cylinder.

[Ron]

Hmmm...I'm confused here.
I took a broken SS line apart once and it "looked" like the same old "plastic" line carried the fuel as stock. It could of been a better grade or material, but the only difference seemed to be one was protected by a "rubber" hose and the other a stainless sprial...???

[Bitsyncmaster]

Hmmm...I'm confused here.
I took a broken SS line apart once and it "looked" like the same old "plastic" line carried the fuel as stock. It could of been a better grade or material, but the only difference seemed to be one was protected by a "rubber" hose and the other a stainless sprial...???

+1
Same goes for the SS clutch line.

[Mark D]

The stainless braiding is just an external cover over the inner hose that actually transfers the fluid.
http://dmctalk.org/attachment.php?attachmentid=22860&d=1383428705

I think the hoses hervey sells have a teflon inner. I'm not sure about the DMCH hoses.

The main benefits to the new hoses are:

1. They aren't 32 years old.
2. They are made from modern materials

For less than $300 it makes sense to me to replace them as preventative maintenance...meaning before they start to leak. I really don't understand any push-back against the recommendation to replace them. Having your car start on fire and potentially burn to the ground is more than reason enough for me to fix this known issue before an actual hose failure. It also makes sense to replace coolant hoses, brake lines, and any other 30 year old rubber parts. This original stuff is all well past the intended usable life.

[Mark D]

The vendors stock and sell stuff that they know their customers will buy. Just because you can buy them is not a good reason to replace the lines.
Sorry, but I disagree. At this point the hoses are past their expected lifespan. It is part of normal preventative maintenance on ANY car that you replace parts once they are no longer reliable and are ready to fail. Just because the fuel hoses haven't failed yet doesn't mean they're in tip top shape and you don't have to worry about it. The failure mode is fuel leaking onto a hot engine. Do you really want to wait until a hose starts spewing fuel to replace it?


The interior is not plastic, it is much tougher than plastic (I don't know exactly what it is but it isn't plastic or rubber).
Yes, it is plastic. The inner part of the stock hoses are made from polyamide, AKA nylon which is plastic.


I do not want Delorean owners to think the lines are a time bomb, ready to explode and burn the car to a crisp.
But they ARE a time bomb. Every single DeLorean on and off the road with stock hoses is on their way hose failure. It could be in a year, it could be 5 years, it could be more... But they will all fail eventually unless replaced. The idea is you replace things before they fail so you know your car is reliable and can make it safely from point A to B. A failed fuel hose can in fact burn a car to a crisp.


It is not that bad unless the lines were abused and you would know it because they WOULD be leaking.
If a hose is so fragile that it cannot be flexed without cracking apart and causing a fuel leak I'd say that means it's time for replacement.


The fuel lines I would be careful about are the ones by the fuel pump. In the beginning people were changing their fuel lines on the motor because they wanted the "look", not for any safety reasons.
The fuel lines at the fuel pump should be replaced just like the fuel lines on the engine. Both are old and past their usable lifespan and should be replaced. What makes the fuel injector hoses on the engine so special that they don't need replacement?


If you feel you need to change lines, change the clutch line and the 4 brake hoses and the one from the clutch reservoir to the master cylinder.
Again, you're advocating preventative maintenance on other hoses but not on the fuel injector lines. This makes absolutely no sense.

[sdg3205]

Is Hervey the only vendor that sells complete kits? By this i mean the hose to the fuel filter and return lines etc.

[Tillsy]

Is Hervey the only vendor that sells complete kits? By this i mean the hose to the fuel filter and return lines etc.

I got mine through Just Bandits in the UK - only ones they couldn't do were the two frequency valve lines, got those through Hervey plus his flexible accumulator<>fuel filter line.
http://dmctalk.org/attachment.php?attachmentid=22861&d=1383431722

[Mark D]

Hervey for sure carries a kit that contains all 13 hoses

6 for the fuel injectors (102318,102323,102327,102339,102335, and 102331)
2 for CPR (102357 & 102348 )
2 for the frequency valve (102400, 102395)
1 for the cold start injector (102370)
1 supply from fuel filter (102365)
1 return to chassis hard line (102359)

According to the DMCH website their kit includes 9 hoses
6 for fuel injectors (102318, 102323, 102327, 102331, 102335, 102339)
2 for CPR (102348, 102357,
1 for cold start injector (102370)

They may also be able to provide the others but you'd have to call and ask.

I have no idea what DPI carries.

[NightFlyer]

Most modern cars use rubber covered nylon fuel lines and nylon fittings as OEM equipment, despite the current standard of E10 fuel.

Personally, I think most failures of the original nylon lines are caused by a weakening of the thermo-coupling of the nylon lines to the brass banjo fittings, as opposed to an actual failure of the nylon core itself. As David T pointed out, hoses that were previously handled roughly are more prone to failure of the nylon core than hoses that are rarely or gently handled.

If paranoid about the thermo-coupled connection of the nylon line to the banjo fittings, you can simply install fuel line grade hose clamps as an added protection. On my car, the banjo fitting on the fuel filter end of the supply line separated from the nylon core upon my last fuel filter change. I simply re-routed the hose to gain some additional length at the filter end, cut it to where there was a solid nylon core present, heated the banjo fitting with a propane torch, re-thermo-coupled the fitting to the line, allowed it to cool, and then installed a fuel line grade hose clamp for added reassurance. 4,000 miles later and no issues present.

For reference purposes, how many people recall the orange fuel line hoses that many vendors, but mostly Grady, were using about 10 years ago? They were teflon lined (with an outer reinforced rubber cover), like the braided stainless lines currently offered by Hervey. They generally experienced a lifespan of 10 years before the teflon lining was degraded by the E10 gas into a gooey substance that eventually ruined accumulators and plugged fuel filters. The stock/OEM nylon core lines have lasted over 30+ years thus far without causing many issues. It's also important to note that many of the recent engine fires that were documented occurred to cars that had been extensively serviced/overhauled, and probably saw a fair amount of handling of the stock/OEM fuel lines.

Just saying...

[Ron]

Are you sure they are thermo-coupled?
I thought I read where they were pressed (or "popped" ) in.
I've see a lot of them that would spin but not leak...and nylon does not like much heat at all.:dunno:

[NightFlyer]

Are you sure they are thermo-coupled?
I thought I read where they were pressed (or "popped" ) in.
I've see a lot of them that would spin but not leak...and nylon does not like much heat at all.:dunno:

That's a great question. I'm not really sure.

When the banjo fitting loosened out of my main supply line, there was a lot of nylon from the inner core attached to the brass barb of the fitting, and it appeared to have been melted/fuzed to the brass barb, which is why I presumed they were thermo-coupled. There was also some nylon from the core remaining in the line, which is why I had to re-rout and cut the line at a point where a fresh, solid, and complete piece of nylon core existed. I thermo-coupled the repair, and doing so hasn't appeared to cause any issues thus far...

I know what you mean about being able to spin some the banjos without causing a leak.

Anyone know for sure and can provide documentation to back up their claim?

[David T]

ALL of parts on the car are well past their design life. Now we get to the example of George Washington's hatchet. The head was replaced once and the handle twice! Replacing parts eventually gets down to judgement and experience. The fuel lines in the engine bay seem to age well. No so, many other hoses including the cooling and brake systems. I agree if you have no confidence in them, then they should be changed, I just do not say it is necessary unless you have a problem with them. The fuel tank is past it's design life. Do I hear anyone who is saying it should be replaced? It is made out of plastic! The hoses for the tank fill are rubber and are WAY past due to be replaced. I have not heard of problems in that area so it is not prudent to say everyone should get new hoses. If we want to err on the conservative side of things get a newer car or a couple of fire extinguishers and a LOT of insurance!