Rubber hose for fuel line??..

[diesel4me]

Found out some boob used about 15 feet of rubber fuel line hose instead of metal on my '85 Suburban with a 6.2..would that contribute to hard starting and it needing a lengthy cranking before it'll finally start??..the former owner installed an aftermarket electric fuel pump near the tank (on the outside of the frame rail,right in the path of salt spray off the tire,and the rubber hose was rubbing on the spring shackle and almost touching the exhaust pipe too!..IDIOT!..)..

They by passed the original lift pump on the engine..I have both an elctric pump and the stock lift pump hooked up on my plow truck,and it works great,should I hook both up in this truck too??..once it finally starts it seems to run ok,the cold advance is working ok,it does seem a bit sluggish though,compared to my pickup's 6.2..

I know the engine has at least 2 dead glow plugs,but even on a 50 degree day I had to crank it for a long enough time to kill the batteries ,and then had to jump it off my other truck,and use a whiff of ether before it would finally fire up....truck has a Raycor filter on it and I see a bit of diesel oozing from the hose connection,so I'll have to fix that--but I dont think any air is in the system..

I was wondering if the long length of rubber has something to do with it or might be aggravation the problem..I'm going to replace it with 3/8" copper line instead,so I wont have to watch it rust away in a year or two anyway..good thing I looked under the truck,or it might have eventually burnt the rubber hose on the exhaust and I'd have burnt it to the ground!--not good,when its not insured or registered yet!..

 

[longbedder]

1) Exhaust from a naturally aspirated 6.2 doesn't get super-hot, and diesel can be tough to ignite - I doubt you'd have started a fire. It does sound like bad routing, though, and you'll probably want to fix it.

2) Just having rubber fuel line would not cause your hard starting issues. Air in the fuel system may cause this issue. Fix your leaks and get your glow plugs working.

3) If you do use copper, be careful about how you mount it. Copper has a much shorter fatigue life than steel and will crack/break relatively easily if subject to much vibration. You'll also get galvanic corrosion where there are any steel-to-copper fittings (like at the lift pump).

4) There's no reason to run two lift pumps. The pressure and volume required on these engines is very low.

 

[Russell]

Stainless or aluminized steel for the win!

 

[6.2Blazer]

Agreed with the above, the rubber line itself should not cause any issues. The likely culprit is the slight fuel leak you mention, it might not seem like much but this would cause a hard starting condition. I've had a leak on mine before and it would never start without draining the batteries and then having to jump it, and the leak was only a few drops when left overnight.

 

[diesel4me]

Thanks for the answers everyone!..

Seeing the rubber isn't an issue (for now,while its cold anyway!), I'll leave the rubber hose until it gets above 30 degrees out,if its not going to be a problem.

.I'll change things around once the weather breaks,like remount the pump on the INside of the frame rail,and if I do use copper line I'll use the steel clamps with the rubber inserts to attach it to the frame like I did on my 74 GMC,it lasted 8 years and never a problem,it did turn an ugly green color though..I used short rubber hose "unions" to join it to any steel lines or connections...

I trust copper more than rusty steel around here--I cut up a few city busses at the junkyard from the 1940's that had copper tubing on the air brakes and heaters,that was still in excellent condition..but I know it can work harden and crack if exposed to vibration..

I was not sure if having two fuel pumps would be an advantage or not,I have seen some factory 90's trucks with both the mechanical lift pump and an electric one mounted on the frame rail..perhaps I shouldn't be running both on my plow truck??--have been for the past 6 years os so with no apparent problems though..it seems to start better and idle smoother with the electric one helping out..was wondering if the injector pump is a bit weak if the two pumps help make up for that during start up..

Meanwhile I'll get some new glow plugs and get all 8 working if possible..hoping I can get the ones behind the AC evap box out!..they are a bear to even see,never mind get at..I was successfull in getting one "dead" one out so far,thankfully it was a 60G and not mushroomed,I am praying all 8 have been replaced as the former owner claimed,and they used 60G's so removal wont be a suck job..

I sprayed a whole can of white lube on the oil pan,tranny lines,brake lines,glow plugs,and anything else I dont want rotted away by spring..I learned the hard way how quickly the 3/8" hex on your glow plugs whittles away to practically nothing in a few years here,making removal "fun"..
I'm wondering if one of those "gator grip" soclkets with all the needles in them would grab the rotted glow plugs in my plow truck good enough to get them loose..(right now they are still working,but two have alligator clamps to attach the wire to the remains on the tab that rusted off them..I'll try using a new 6 point socket first,then try metric or whatever size under 3/8" might work,if that fails I'll be looking for another idea..one guy suggested a cam action stud remover,I dont see one fiting in where it needs to go though..

Wish it would warm up some here..its too cold to snow even!---the frigid air keeps pushing all the storms south of here to NJ,MD,and VA,etc..weird winter!--I'm not complaining about no snow though,my plow truck isnt exactly in tip top shape right now and has a multitude of problems..

 

[77crewcab]

In all honesty you could pour diesel on the exhaust manifold of a running engine and it won't do anything but smoke. The engine isn't hot enough to ignite the diesel fuel. The only part of the engine that gets hot enough to do it is in the combutsion chamber of the head.

 

[DEMON44]

diesel rated fuel hose if fantastic stuff. regular "rubber" line is junk, it can and will become porous. not visual to the naked eye. change it to new line if theres even a question about it. I use goodyear gatorgrip. its diesel rated and I love the pushloc hose ends on it to JIC usually. its sweet. you don't at all, need hard line. not at all.

2 lift pumps is not nessissary. 1 that works is more than that engine would ever need.