replaced glow plugs, timing set, wp, and more, now startes and dies

[merlot566jka]

Ok, heres whats going on...

I replaced the timing set, water pump, balancer, glow plugs, power steering pump and resealed everything that i could while i was in there. on day 2 of this adventure, i saw a huge puddle of fuel and dripping fuel from the tank, i didnt think much of it and put that on the back burner till iw as done with everything else.
I got it all put back together, go to fire it up and it just cranked and cranked. as expected because of air in the lines. It finally caught then died. I had someone else crank while i bled the filter, it was pumping nice and clean with no bubbles from the top outlet. so i figured it was good on getting fuel from the lift pump. but same deal, catches and then dies.

I am assuming its air in the lines (and really hoping thats it). the fuel drizzling from the tank has got my attention now, why would it take a couple of days to start leakin like that? did it start to leak when i disconnected the fuel lines? (i had a slight mishap, the alt slid down and touched the lift pumps line and sparked a hole strait thru the line! I cut the metal line, repaired the lines with fuel injection hose and tested for a leak, all is good.)
if there is fuel at the lift pump, and the engine is starting and dieing, that rules out being air locked, right?
That would indicate that there is an air leak some where, correct? (maybe the fuel coming out of the tank, is acutally coming out of a bad hose?)
i dont have any way to get air into a filler cap to test for leaks right now, is there another way i can go about it?

thanks for any help.

btw i have to drive to wa state in a few days and im in oklahoma now, not having fun!

[DmaxMaverick]

You still have a lot of air in the line, causing the start/die. From the sound of it, the air isn't going away, but is sucked in (drain-back) at every engine-off episode (endless cycle....until you run out of fuel). The engine starts and runs, until the "bubble" hits the pump, then it dies (unable to build pop pressure). You have a leak in a fuel line at some point in the system. Could be a bad piece of old hose/tubing. Could also be when you arced the line up front, it also grounded somewhere closer to the tank as well, creating another hole. If the line isn't isolated (not continuous, electrically) between the leaks, assume that has happened. Once you fix your fuel leak, my bet is your system will prime like it's supposed to and run fine. You could test the theory by supplying the pump with another fuel source, independent of the OEM lines. A fuel can above the filter, connected to the inlet will do it (gravity). Also, a healthy pump will draw fuel, even when the lift pump fails, at least enough to run the engine at idle and lower power demands.

[merlot566jka]

ok cool, thats kinda what I wanted to hear.

I should be looking on the suction side of the lift pump, correct?

Should I crack an injector line or two, or is this all before the IP?

the line that arced was the suction from the filter to lift pump... but good point, ill examine that entire piece of line, it could have grounded to many things, incl the lift pump its self. i should see fuel if thats the case.

Maybe if i use a hand vacuum pump with a clear hose, I could pull a vacuum on the lift pump inlet, and see if there is air coming in. Im going to replace the lift pump anyways since i have a new one just sitting here. shouldn't hurt anything.

[DmaxMaverick]

If it's leaking between the lift pump and the injection pump, it will leak fuel externally while the engine is running (under pressure), then allow air to enter while the engine is off. If it's leaking between the lift pump and tank, it will suck air while the engine is running, then leak fuel and/or drain back to the the tank with engine off (depending on the level of the leak, in relation to the fuel level in the tank), and will never fully prime. If you have fuel leaking externally, either way, nothing will be right until it's fixed. Also, check the fuel filter(s).

[merlot566jka]

''''If it's leaking between the lift pump and tank, it will suck air while the engine is running, then leak fuel and/or drain back to the the tank with engine off (depending on the level of the leak, in relation to the fuel level in the tank), and will never fully prime. If you have fuel leaking externally, either way, nothing will be right until it's fixed. Also, check the fuel filter(s).''''

great, ill get under it in about 5 mins and start checking lines. the fuel filter has about 2000 miles on it, but that doesnt mean much, ill see if i can grab another one.

from what you said and what its doing, the leak is between the tank and lift pump, and the fuel level is low enough to have an impact. after cranking for a bit i did go check the filler cap, and there was a suction sound of air rushing past the filler cap as i took it off, i figured maybe that meant that there was a vacuum in the tank and wasnt a horrendous leak.....




ok heres where im at...

I used my brake bleeder vacuum pump and pulled about 15in vac on the fuel line from the lift pump to the filter. no bubbles, plenty of fuel.

pulled a vacuum on the outlet of the fuel filter to ip(barbed fitting on the filter) plenty of fuel, no bubbles.

took off the line that is on the passenger frame rail and bingo, fuel starts dripping from the tank. pull a vacuum on the hard line, and i get fuel, no bubbles. so my leak is around that line i assume.

when draining off that fuel i noticed what smelled like gasoline. maybe my senses are fried from all the chemicals the past couple of days, or maybe there is actually gas in my tank.
maybe while it was leaking, it bled down far enough to get into the last little bit in the tank and its got gas in it. (which is heavier, gasoline or diesel?)

Im going to reconnect all the hoses and get under the back of the burb to see what the deal is with the leak right now.

to add to this, the burb is on a slight hill, where the front of the vehicle is higher than the rear, and its got about 1/16th of a tank of fuel. the fuel drains back to the tank rather fast. it drains fast from the lift pump outlet thru the lift pump inlet and back to the tank. is there supposed to be an antidrain back valve somewhere?

[merlot566jka]

hole in the tank, cleaned the area, now fuel is just streaming out.

think rtv will seal her up?

lines on the frame rail look ok, there are a couple rubber hoses that im going to replace.

are there rubber lines on the top of the tank?

[Subzilla]

Had a leak on my gasser S10 and patched it up with JB Weld. I drained the tank, sanded, and cleaned the area really well. Then slabbed on about 3 layers of JB. I had a couple of holes a little bit bigger than pin holes where gravel had gotten between the stone shield (how ironic??) and the tank.

Yes, there are rubber lines on top of the tank. Never replaced mine - not looking forward to it either.

[merlot566jka]

patched the whole in the tank with some tinfoil and rtv, its holding.
http://i26.photobucket.com/albums/c134/merlot566jka/IMG00355.jpg

jacked the back end of the truck into the stratusphere, it runs with my foot in the throttle!

popped off the fuel filter, look what came out of the inlet
http://i26.photobucket.com/albums/c134/merlot566jka/IMG00356.jpg

[DmaxMaverick]

The correct thing to do at this point, is to remove the tank. It needs a thorough flush. At the same time, have the hole repaired properly (RTV is very temporary, have it welded). Or, replace the tank. Much depends on the overall condition of the tank. They can be repaired and sealed (internal coating), but many times, it isn't worth it. The complete fuel system also needs a flush, by the looks of your sample. Don't run it until you do, or it could trash your LP, IP and injectors. And, your filter was probably used up, regardless of mileage.

The incorrect thing to do would be anything less than this.

[merlot566jka]

woops, i went and put 5 gal in and a new fuel filter, it runs with my foot in the throttle and TONS AND TONS of smoke. its really quiet and not much of the diesel rattle sound.

timing?

[john8662]

Remember, the first rule of working on the engine is to disconnect the battery cables.

The smoke could be due to poor fuel quality, or related to anything concerning the repairs performed, ie timing.

J

[merlot566jka]

john, i think i will keep the battery disconnected from now on, lol.

well i kept my foot on the throttle for a bit, and then it would idle on its own, it was extremely low quiet idle, with plenty of fuel scented exhaust. i have advanced the timing about 1/16th of an inch towards the drivers side.

tomorrow im going to go ahead and get the filler cap and valve stem, and prime it up to look for leaks, and then try it again. i was supposed to go see my daughter tomorrow, but now it looks like im stuck. again.

after that, ill start on the timing. is it possible that the timing is off? as far as the timing set and injection pump drive gear go? nothing moved while it was apart, and the dots were lined up on the injector dive gears. ----to add the lines on the cover and pump were perfectly lined up when i took it apart, and there was a good amount of stretch on the timing chain once it came off. what would make sense to me, is that the pump should be too advanced when installed with a new chain on there and the lines are lined up on the cover and pump. but if there is air, it will retard...if there is a back up on the return, it will retard. ahhh what the hell

im going to get drunk for new years, and maybe in my hangover stupor ill get it figured out

[merlot566jka]

installed a clear hose on the ip return, no air bubbles.

timing or lift pump?

i advanced the sucker as far as it will let me, no changes.

[merlot566jka]

ok replaced the lift pump and got bubbles! the pump was full of the same crap that was in the filter, of course.

i replaced a few hoses, no more bubbles.

still has white smoke and idles really low and quiet. so i loosened the ip, retarded it and advanced it while the engine was running. the result, more smoke when retarded, and when advanced to the max, the idle gets slightly better and starts to sound like a diesel.

is it possible that the marks on the ip gears is off? i guess im going to have to pull the damn front cover again and check it out.

how do i advance it using the gears? meaning where do i move the dots realitive to one another? maybe its only off by a tooth or so

[DmaxMaverick]

DO NOT try to adjust the timing by jumping teeth!!! The 6.2L Diesel is an "interference engine". Meaning, if the valve timing gets too far off, it WILL destroy valves, pistons, etc. Advancing the pump via a gear jump will take you outside your optimal envelope, making your valve to pump timing never right. If the chain is worn, replace it. No other option.

That said, your pump timing adjustment results could indicate the chain/sprockets are too worn and need replacement. And remember, the IP rotates opposite the crank/cam. You may have your advance/retard understanding backwards. Retarded timing will produce a quieter engine with more white smoke, while advanced increases Diesel rattle. None of it means a thing unless the entire fuel system is healthy, including injectors.

[merlot566jka]

DO NOT try to adjust the timing by jumping teeth!!! The 6.2L Diesel is an "interference engine". Meaning, if the valve timing gets too far off, it WILL destroy valves, pistons, etc. Advancing the pump via a gear jump will take you outside your optimal envelope, making your valve to pump timing never right. If the chain is worn, replace it. No other option.

That said, your pump timing adjustment results could indicate the chain/sprockets are too worn and need replacement. And remember, the IP rotates opposite the crank/cam. You may have your advance/retard understanding backwards. Retarded timing will produce a quieter engine with more white smoke, while advanced increases Diesel rattle. None of it means a thing unless the entire fuel system is healthy, including injectors.

I found the problem, cam was retarded 1 tooth. i cant believe i did that. thats never happened before, and ive built about 15 engines. well whatever, its 29 degrees out and i just have to put the accessories on and fill the coolant. but im tired. just another few hours and i should be done with that and beable to fire it up.

[merlot566jka]

ahhh the wonderful sound of rattle, rattle, rattle.

runs like a champ.

think my radiator is leaking now. it never ends!

gonna do shocks and cleaning in the morn and get a windshield. then itsoff to tx for a day, then to WA state.