How long should I have to crank after injector replacement (OM616)? - Page 3 - PeachParts Mercedes-Benz Forum

vstech · #1 07-02-2012, 02:40 PM

Quote:

Originally Posted by BodhiBenz1987

When you say #1 failure, do you mean within the IP? I did get fuel there eventually, but it took longer than the others for sure. I'll do a search on that for evening reading material (it beats Sunday night TV).

no, I mean cylinder #1 on the engine is known to fail on the 240's due to low fuel pressure to the IP...

splunge · #2 07-03-2012, 04:06 AM

In a situation such as this, where algae fuel contamination is suspected, would it help to try to use a siphon hose (e.g. a cheapie shaker siphon) to pull a fuel sample from the bottom of the tank? Or is the algae too viscous or some such to be picked up properly?

Is this siphon method an acceptable approach to draining the tank, if need be? What is the canonical method?

I've been running Racor biocide and Stanadyne Performance Formula in my 240, and have been wondering whether the demulsification has over time created a pool of water in the tank (with any algae suppressed by Racor). Haven't yet tried to poke a siphon in there to try to find out.

funola · #3 07-03-2012, 08:51 AM

Take out the fuel sender, easier then siphoning or draining the tank. if you see black on the aluminum fuel sender, you have algae.

BodhiBenz1987 · #4 07-03-2012, 09:20 PM

I set up a bottle with fresh diesel in it, changed both filters (filled spin on with fresh diesel), primed ... no start ... even with pedal down, I can't even get a little try out of it. There is some reason I can't get air out of the system, and I really don't understand it. Maybe my primer pump is broken (already). I continually get air bubbles in the clear fuel hose between the spin on filter and IP. No matter how much I pump, more bubbles appear, and they don't always come out of the loosened bolt on the spin-on filter (plenty of diesel does though ... there is just diesel everywhere in my garage).
I used the same set-up as the dieselgiant tutorial, only with diesel instead of DieselPurge. Fuel does drip out of the return hose, when I prime or when I crank. But it's not always coming out of the fuel lines on the injectors.
Taking a break ... the diesel smell is making me sick.

funola · #5 07-03-2012, 11:15 PM

Try this:

With all seals tight, crack open the banjo bolt on the fuel pressure relief valve on the IP (backside, facing the block near the temp sender), then use the primer pump to get the air out of the filter and IP. Tighten the banjo bolt. Make sure all 4 glow plugs are good and getting voltage. Crack one injector nut and crank till it starts, tighten the injector nut and feather the throttle and watch the clear return (cigar hose replacement) line till the bubbles clear.

If you can't get it to start after all of the above or can't get the bubbles to clear if it starts, you need to get the Mityvac out and find where it is leaking air in.

BodhiBenz1987 · #6 07-04-2012, 08:45 PM

Update: It started again, and ran a while at part throttle ... better than the last time. Stayed pretty even at 1,500 rpm. When I tried to let off a little to see if it would idle, it quit.

I can't see whether there's fuel and/or bubbles in my clear line. I made a video but it will take me the rest of the night to figure out how to get it on my computer.
That sounds like progress, but now I'm back to ground zero. Won't start again. Bubbles gallore. It's sucking them in somewhere. Again, all the bubbles are in the line between the pressure valve and the spin-on filter. A bunch of them moved through the line as I pumped, but now there's just that big pocket of air at the top again.
I guess the next step is to find the leak. There doesn't seem much point going through all the priming again until I've done so.

vstech · #7 07-01-2012, 09:01 PM

heck, I'd start with a "diesel purge" bottle of fuel connected to the lines of the tank in www.dieselgiant.com/injectorcleaning.htm style...

BodhiBenz1987 · #8 07-01-2012, 09:20 PM

Quote:

Originally Posted by vstech

heck, I'd start with a "diesel purge" bottle of fuel connected to the lines of the tank in Diesel Purge Mercedes diesel maintenance tips style...

This might be a good idea. I probably should have done it when I bought the car. Should I just try to rev the engine like I did before during this procedure? I guess if the problem is fuel contamination, it will run better when connected to the bottle.

colincoon · #9 07-01-2012, 09:30 PM

Quote:

Originally Posted by BodhiBenz1987

This might be a good idea. I probably should have done it when I bought the car. Should I just try to rev the engine like I did before during this procedure? I guess if the problem is fuel contamination, it will run better when connected to the bottle.

While a diesel purge isn't a bad idea, he's telling you to use the remote "tank" like you would with a diesel purge, just with diesel now.

I really think you should try this first before doing anything else. Grab a 2ltr soda bottle, or something of equivalent size, and put in some fresh diesel. Cut two holes in it, one for supply and one for return, and run fuel line in to it and hook it up to your car. Prime and attempt to start it like you would normally.

Sitting for 6 weeks is plenty of time for junk to build up and cause issues.

BodhiBenz1987 · #10 07-01-2012, 09:39 PM

Quote:

Originally Posted by colincoon

While a diesel purge isn't a bad idea, he's telling you to use the remote "tank" like you would with a diesel purge, just with diesel now.

I really think you should try this first before doing anything else. Grab a 2ltr soda bottle, or something of equivalent size, and put in some fresh diesel. Cut two holes in it, one for supply and one for return, and run fuel line in to it and hook it up to your car. Prime and attempt to start it like you would normally.

Sitting for 6 weeks is plenty of time for junk to build up and cause issues.

OK, that makes sense. I'll follow dieselgiant's instructions, but substitute normal fresh diesel in the bottle.

layback40 · #11 07-01-2012, 10:16 PM

Quote:

Originally Posted by BodhiBenz1987

OK, that makes sense. I'll follow dieselgiant's instructions, but substitute normal fresh diesel in the bottle.

Its great to see you making progress !!

Fresh diesel is always a help.

For a bottle, I have used an orange juice container, they are clear so you can see the diesel in it. The opening is big enough to put the 2 flexible hoses (cigar & supply to primary filter) in.

An extra claim to fame you now have is you got BC & I to agree on something !

Keep the throttle to the floor !!

If you drain the tank & find black gunk in the strainer, it would be fair to say the problem is found.
The tank vent is probably blocked, they always get that way. Until you have it sorted, leave the fill cap off.
A good nights sleep always diminishes mechanical problems with a car !!

colincoon · #12 07-01-2012, 09:03 PM

Yeah, set up a remote tank and try that. It sounds more like fuel starvation now than injector problems.

layback40 · #13 07-03-2012, 11:15 PM

Oh Dear !!
Looks like you have a leak of air into the fuel.
Is the little primary filter part of your set up? They can have leaks around the hose fittings.
The most likely place air will be getting in is on the vacuum side of the primer pump. Is the hose good?
Are you getting a good stream of fuel out the return line when you pump the primer?

I had an annoying air leak on my diesel jeep. It has a similar fuel system. I ended up using a can of spray glue & making a mess spraying every connection 1 at a time & testing until I found the air leak.
Probably if I was as frustrated as you must be by now, I would put a small electric fuel pump in the line from the bottle & set it going for a while circulating fuel under pressure until every bit of air was gone. But thats just me!
I prime my 617 by attaching an air hose to the return line to the tank & lightly pressurizing the tank. It has the old style primer pump & it leaks & so destroys engine mounts & I have trouble getting it to seal after priming. You can hear the air exiting the tank vent. The return line out of the filter housing I have going to a bottle. When there are no more bubbles of air, I quickly reconnect the return line to how it should be. It takes some skill as if you are not quick, the diesel under pressure in the tank comes back up the return line & gives you a face full of diesel. Dont ask how I know !!

What happened with the WD40?

Sorry for asking so many questions, its just my way of making suggestions (the answers).

BodhiBenz1987 · #14 07-04-2012, 07:47 PM

I doublechecked the fitting around the primary filter (which is new) and tightened the hose clamps a little bit. The supply hose should be good, I just bought it. I made sure it is fully submerged in the bottle of diesel. When I pump the primer I can see the hose pulse (if that's the right word). I can't see any air in the primary filter (not even the normal bubble). I tried:
-cracking the bolt that goes from the secondary filter housing to the IP and pumping. Diesel (no bubbles) comes out.
-cracking the banjo bolt on the side of the IP near the temp sender and pumping. Diesel comes out without bubbles. I pumped a bit of diesel through then tightened it.
-adding the clear tube where the cigar hose was on the last injector. I can see diesel begin to rise in it when I pump the primer, but not a lot.
-cracked the injectors nuts again. Bubbles and fuel came out of 1 and 2, closed them once it was steady fuel. Cranked again until bubbles and fuel came out of 3 and 4. Fuel now coming out of all four. Tightened.
-recharged battery (overnight)
-checked voltage on all four GPs
-cranked with throttle all the way open ... it is not starting. It is now back to (what sounds like) catching on a couple cylinders and sounding like it's close to starting, but no go.
Also tried, for the heck of it:
-removed vaccuum line from shutoff valve
-removed crankcase hose in case it was maybe obstructed and causing back pressure

I am not getting a huge stream out of the return hose in the bottle when I pump the primer, but it is a small steady stream. I tried submerging that hose to see if air was coming out and it wasn't. I'm not seeing air bubbles moving through the hose on the back of the IP anymore (which I was getting yesterday), but there is a big fat air bubble sitting on the top of it, near the spin-on filter. Nothing happens to the air bubble when I pump, regardless of what bolt is cracked. It's just sitting there peacefully, and it got a little larger overnight. I'm assuming there is not supposed to be a bubble there? I can post a photo if it isn't clear which hose I'm talking about.
If my dad wants to stop by when he's done working this evening, I will try the WD40. I have not yet ... I assume there's not point in trying to spray it myself and then start ... it would just end up in a puddle in the air filter housing, right? I have a feeling it will start and just die out again, but I guess it is worth a try in case my bleeding efforts made any progress and there's just a little air left.
Only thing I haven't done yet is take the glow plugs out to watch them and make sure they glow fully ... guess I will try to do that now without burning myself or something else. Would also be easier with a helper.

Hope everyone is having a good holiday.

funola · #15 07-04-2012, 08:52 PM

Looks like you have bled it well enough and it should have started. The fact it had not a hint of firing is baffling. Have you adjusted the valves since the last time it ran? Is the shut off lever on the IP in the correct position and not in the shut off position? I mentioned it before, that lever can be put into a position to not let fuel through normally (happened to me after a valve adjustment, which required removing some of the linkages).

Can't hurt checking the glow plugs for actual glow. Make a video so we can hear how fast your starter is cranking. The bubble getting bigger overnight indicates an air leak. There should be no bubble in any fuel lines after all air has been bled out from running the engine.