diesel won't start

[cornflake_4x4]

I changed the fuel filter for my 85 6.2 diesel blaze, and in everything i read, it said to remove old filter, install new. The previous owner removed the stock filter and replaced it with a canister style one on the firewall. I work at a Chevy dealership, so I asked a tech and he said that i should have filled the new filter with fuel, but to get out the charger and crank away. I was told that it would eventually start. I pulled the filter when i got home, filled it and tried to start it for a long while, to no results. Battery is now dead, hence the charger. Just wondering if I'm on the right path. Any help would be greatly appreciated

 

[Brocky]

I have a diesel Mercury Topaz. I went thru the same problems. I took the fuel line off the intake and stuck a little vacuum pump on there and when the fuel started to come out I put it back together. I have clear fuel lines on the top of the engine so I can see the fuel. I believe the problem was a result of no pressure on the line when I removed the filter. I hope this helps.

 

[Pookster]

Canister style is older than the square ones. Square ones are the model 80 Racor filters. They are acutally quite good in a lot of respects (heated for example) but terrible in others (cant pre-fill).

If he's removed the new style, the old canister style should have two- one for the large one on the fire wall, the other should be right below the air filter (also a canister).

If you've pre-filled, usually your "ok" for a restart. But if you didnt pre-fill, and cranked already, you probably have air in the system.

I cranked the living crap out when I got air in my system.

If your battery is dead, try charging it first. Get a buddy, open up the air cleaner. remove anything that can be sucked in(sleves, long hair, ties, etc).

(Get a second opinion on this method)

Get a can of WD40 (NOT STARTING FLUID, I REPEAT < NOT STARTING FLUID). WD 40 will work as fuel, its a little odd, but it does work. Have a buddy glow the system, and start cranking. Start spraying wd40. Try to mist it over the intake, rather than puddling it inside. The engine should roar to life. Keep spraying it. The more you spray, the higher the engine RPM, so you may have to stop spraying. This will keep the fuel pump moving, and spray out whatever air you might have in the lines. Eventually, you will stop spraying, and the engine will be running by itself.

 

[tRustyK5]

As you found out changing the fuel filter is a little more involved on a diesel than it is on a gas engine. you just air-locked your motor, and there is an even chance you burned up your starter too.

From where you are now the first step is to charge the batteries 100%. Step 2 is to remove all 8 glow plugs...you will be spinning the motor over a fair amount and it's a ton easier on the starter with the glow plugs removed. Make sure all the wires are still connected to the injection pump. Loosen all 8 fuel lines from the injectors so they're loose but not off.

Now have a helper crank the motor for 15 seconds while you watch the fuel lines. Let the starter cool down for 30 seconds to 1 minute and repeat. Always rest the starter between cranking. When you see fuel begin to drip from a fuel line tighten that one up. Once all the fuel lines have had fuel dripping and have been tightened up re-install the glow plugs...let them cycle and try and start it. It should start, and it should run a little rough at first but smooth out pretty quickly.

Rene

 

[Kiwi John]

Air

Rene is right. U'v probably got air thru into the pump side of the fuel circuit. Ignore anybody who tells u to just crank until it starts, it probably won't. once air gets into the circuit past the filter (when u changed thecanister) then it is in the high pressure part of the system on the pump side of things. The pump is trying to pump liquid fuel, the air is gaseous and so it just sits there compressing and expanding, not pumping fuel cos it cant generate the presure to lift the injector nozles off their seats. Thats why you have to relieve the pressure at the injectors by "cracking open" the nuts on the fuel lines, letting the pump push out the air and closing off the "leaks" when fuel appears as a drizzle at each injector.
All diesel systems i've worked on have some formal way of bleeding the fuel system though. Look for a bleed nut (often looks like a bolt not quite screwed in properly, but is done up tight, sometimes with a groove down the thread, or a hole drilled up the centre and cross drilled at the top., so the fuel can leak past after you loosen it a couple of turns.) on the top of the fuel filter head assembly. There should also be at least one on the body of the fuel injector pump.
But start with a methodical and sequential bleeding operation. :
There is another pump somewhere which brings fuel from the tank to the engine. This is called the "Lift Pump" (here in UK anyway) cos unless u have a gravity-fed system, you have to 'lift' the fuel from the tank (low down) up to the level of the engine-mounted 'Injection Pump'. It may be an electric or mechanical operated pump.
Cranking the engine (glo-plugs out) will be easier on the battery and starter motor for sure.
I haven't had my diesel Blazer long enough to need to get up-close-and-personal with the fuel system but i'm sure the Clinton or Haynes manuals tell you what to do from here.
Bleed the fuel filter assembly. Filling the canister first saves you time.
Bleed the fuel line to the injector pump.
Bleed the injector pump.
Bleed the individual fuel lines, to be certain of clearing all air...
And you should be running soon!
Oh, and put the glo-plugs back in if it wont start!!!!
There is a section of the website dedicated to the Diesel engine that may have more-knowlegable scribes the me if that helps. Good Luck.

 

[diesel4me]

this is why...

I left the universal electric fuel pump on my 6.2 truck--someone installed it inline before I bought it between the fuel tank and the fuel line that goes to the filter on the firewall---all I have to do is install the new filter,open the petcock bleeder dewhickey on the top of the filter housing,and turn the key on--the fuel pump comes on,fuel fills the filter,and when it gushes out the bleeder,its all set to fire up....but I've yet to change my fuel filter... it looks fairly new,(but I should anyway--but I dont have 15 bucks for it!)...I still fear it wont start right up though!...but the pump should help at least..--

We had a nightmare on a customers truck with a 6.2 that had the cartridge type filter in the intake manifold..my friend didn't know much about diesels,and he just took out the old one and threw in the new one bone dry--and cranked it until the starter was JUNK! --after we put a new starter in (150 bucks later,and the customer was PISSED!)--it still took us a few hours to get it fired up--had to loosen all the injectors,and finally got it bled enough and by using WD-40 we got it going... I hope I never run my diesel out of fuel!...its not like a gas motor!!.

 

[cornflake_4x4]

thanks

thanks, got it started, still running wrong though. maybe some air still in system

 

[Kiwi John]

Am just replying to get this thread put with your other one in the index list as they go together.
Running rough means air still in there somewhere fella.

Maybe Rene can join them together?