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Disaster of a fuel leak

Started by Zagato, 25 June 2009, 09:03 PM

Zagato

So I need new hoses for my injector rails. After noticing a strong smell of fuel upon start up, I popped the hood and found some of the hoses, that deliver fuel from the rails to the injectors, to be drizzling fuel onto the intake manifold. I count at least 4 locations. However, it only drizzles during high RPM (such as warm up idle of 1,700). I can get it to the shop by the 6th of July, at the earliest.

I ask, is it still safe to drive? It'll mean I have to top up the tank every 2 days, but is it a fire hazard?

Ryan1980

one would think so, if it drips onto your exhaust or something hot it could ignite.

oscar

Yeah I wouldn't be too keen on driving it round too much.   

I know of two occasions where my 350's had leaking hoses and was driven.  Without going into too much detail, once I must have driven it for more than a week and covered around 100km before I found where the smell was coming from.  Thing is, in a V8 the fuel's going to sit around the injectors and plenum or in the "V" so it's not really going to get hot enough to combust BUT, whilst my leaks did pool a little it was from slow weeping through the hoses.  If you got drizzle which sounds more than what I had, it just doesn't sound real safe does it.  You get the right amount of gas in the air under the bonnet from standing overnight and a spark from the starter motor, whatever is exposed will catch.  I may have been lucky before, maybe the chances of the fumes igniting from a rogue spark is slight, but it's real easy to get busy with some FI hose and a screwdriver and fix the prob yourself to keep peace of mind.  Follow up with a pro job afterwards if you like but it's not too hard to attempt this yourself IMO.
1973 350SE, my first & fave

TJ 450

Sounds very dangerous. You should be able to replace all of those hoses with generics from an auto parts shop for very little $$.

A warm idle of ~1700RPM is way too high, or were you opening the throttle?

Tim
1976 450SEL 6.9 1432
1969 300SEL 6.3 1394
2003 ML500

Zagato

Whoops, sorry. Drizzle was the wrong word. It drips from one injector hose at the very most. The other affected hoses, they only seep from the edges.

QuoteYou should be able to replace all of those hoses with generics from an auto parts shop for very little $$.
Are the hoses really that easy to come by? I spoke to a repair shop, and they say these hoses may be hard to find, though obviously they could be wrong.

None the less, are there part numbers for these hoses? I need them for the injectors, as well as for the ones that connect to the idle valve assembly.

QuoteA warm idle of ~1700RPM is way too high, or were you opening the throttle?
No I wasn't opening the throttle. If the car is turned off for several hours, it warms up at 1700RPM. There is a problem with the idle valve.

Quotebut it's real easy to get busy with some FI hose and a screwdriver and fix the prob yourself to keep peace of mind.
I'll try to tighten the hoses up a bit with a screwdriver in the mean time. If the hoses are easy to get ahold of, I may do the job myself to get experience.

Desert fox

I had all my injector hoses replaced recently and although I can't remember the hose diameter it
did not appear to be a standard size but after a bit of a search some was sourced from a specialist supplier.

oscar

Here's pictures of the kits Link.  Notice the two types and the pricing differences. (top is for one pair, the second is pricing per hose piece). 

All I did was buy about a meter of FI hose and used some old clamps plus bought some new generic clamps.  As far as I know, the second kit is the type that was original on my car, but when one side leaked, I couldn't justify the expense of staying original.  Thing is, I can't remember hose diameter either.  I bought 6.5mm and 7.5mm in prepackaged form which both looked about right.  I'm nearly confident to say it was 7.5mm inside diameter that I used. 
1973 350SE, my first & fave

Zagato

The shop says parts will cost $400, and take 2 weeks to arrive. All together, plus labour, will be $900.
Clearly I feel that's a rip-off, and 2 weeks it too long of a wait.

I'll take it upon myself to do the work on my own. I'll buy FI hose from an auto shop, instead of waiting 2 weeks for German originals.

QuoteI'm nearly confident to say it was 7.5mm inside diameter that I used.
I hope so. I'll go with that measurement.


Thing is though, I need hoses for the longer hose that connects to the back of the fuel rails, and hoses for the one that connects the rails to the idle valve. They identical to the injector hoses?

oscar

Quote from: Zagato on 01 July 2009, 10:13 PM
Thing is though, I need hoses for the longer hose that connects to the back of the fuel rails, and hoses for the one that connects the rails to the idle valve. They identical to the injector hoses?

Yeah they are so far as I used the same diameter hose on those bits too.  The only hoses I didn't do are the ones to the right hand side bank of injectors which were still in good shape.  I still can't confirm exactly what size the ID of the hoses are, I was hoping someone else knew, but at least 1m lengths of either type will only set you back $10 or so each.

$400 for parts is one thing but another 5 for labour :o  It no doubt took me longer than it would've for a pro but geez it wasn't that time consuming.  My only tip/observation was that the hoses on the injectors were difficult to remove, they don't simply slide off, they feel stuck on and I couldn't twist and turn and pry them off.  I had to use a stanley knife to cut the top of the hose then peel and tear the hoses apart off the injectors with pliers.  Be careful not to run the knife down the side of the hose or you risk scoring the fuel inlet of the injector, which if deep enough, may cause leakage no matter how good the hoses are.   

I was going to mention residual fuel pressure too before you crack open a line but I suppose there wont be any due to the leaks ::)
1973 350SE, my first & fave