Fluid advice for bringing a dry engine back to life after 2 years

[halfspec]

Hello

My e39 540i/6 started eating its timing guides at the end of 2019, so I parked it until I had the time to do the repairs. I was in the middle of a move and then the pandemic hit, so it took 1 1/2 years to get to it. I ended up spending about 4 months over 6 months (wasn't able to work on it through the holidays) of weekday nights working on the car which scope creeped in a major way. I've finally got the engine back in and aside from my interior being stripped (had some mold growth I had to take care of due to the door vapor seal + dark storage), I'm actually buttoning this thing up and getting close to having a functional car again.

My questions are related mostly to fluids, but in general, I'm just trying to avoid pitfalls that would cause my issues when I turn the key.

1. Gas - It's got 2 year old gas in the tank. I don't know how much, but I think it all needs to come out and replaced with fresh. I haven't had much luck with getting it out after removing the fuel filter (also being replaced) below the drivers seat. I figured it would just come out with gravity, but it appears its valved or plumbed so that doesn't happen by accident. Any slick ideas to get the remainder of the gas out, or should I involve the fuel pumps to pump the fuel out?

2. Oil - Engine is really dry. I broke it way down to reseal when I did the timing guide work. I expect the default of filling the engine with oil through the engine inlet will get it, but is there anything else I can do to help circulate / pressurize the oil? I.E., would it help if I added some of the oil through the oil filter housing? Or perhaps it would be ideal to turn the engine over by hand or with the starter + disabled EFI to get my fuel pressure up before I do a real crank?

3. Coolant. Pretty much the same boat as gas. The engine is almost dry. I expect a regular fill will get me in the ballpark since I have a little more time to get everything completely burped but I'm all ears if there's anything extra I need to do.

4. Hydraulics + Trans / Diff oil. I think these should be pretty straight forward. My 6MT is emptied, but I'll fill via normal procedure before I move the car. Same with the diff. I replaced the clutch hydraulic hose because it looked rough when I had the engine out, so I'll be power bleeding the entire hydraulic system before the big event.

5. Electronics - The battery has been deep cycled for ~ 2 years now. It was a 5 year old battery in 2019 so I didn't bother with putting it on a battery tender. That said, the car hasn't had electrons flowing for years. I'll be putting in a new battery and I don't expect I'll have any big surprises with the car, but I wanted to ask about the keyfobs. I bought new fobs in 2018, so they're still pretty new, but since the keys are rechargeable, I don't expect that battery chemistry has any juice left after 2+ years. I know the e39 recharges the keys @ the column, but I don't know at what state the car charges the keys. I.E., Does the car charge the keys if you just insert them, or do you have to turn the key to ACC / ON before it enables charging? I'm just looking to see what I need to prep for. It's no problem putting the new battery in + a trickle charger to charge a key up overnight. I'd just like to know that it's actually charging vs wasting time

Any other advice is greatly appreciated
Lane

[JimLev]

1) Disconnect the fuel line from the filter, then jump the fuel pump relay. That will pump out the fuel in the tank.
2) I'd spray some fogging oil in thru all the spark plug holes, add oil to the filter housing, pull the fuel pump relay or fuse pulled, crank the engine until the oil light goes out.

[effduration]

1) Disconnect the fuel line from the filter, then jump the fuel pump relay. That will pump out the fuel in the tank.
2) I'd spray some fogging oil in thru all the spark plug holes, add oil to the filter housing, pull the fuel pump relay or fuse pulled, crank the engine until the oil light goes out.

plus 1 on this....

you might be due for a fuel pump change ?? If so you can jump the old fuel pump directly under the rear seat and attach a hose to a bucket to pump out the old gas..then replace the pump.

[halfspec]

Thank you @JimLev & @effduration.

I wish I'd known about fogging oil before I reinstalled everything and I would have sprayed a lot more haha! As it is, I'll buy a can and hit the spark plug wells. Appreciate the other tips too.

As for the fuel pump. I replaced it in 2018 and probably haven't even put 10k miles on it yet. I'll just jump the installed pump at the relay and try not to let it run dry for more than a few seconds.


Thanks again fellas
Lane

[Jason5driver]

You can buy a small hand held battery powered siphon pump , and siphon the old fuel out from the back under the rear seat .
You can also use some fuel treatment as well ...
https://www.autozone.com/fuel-and-en...E&gclsrc=aw.ds

[SW530]

I'm probably going to take a different approach. I've actually stored cars in the recent past, once for three years and once for six years. The first time with 3 years I made sure to have the tank filled with a non-enthanol fuel and fresh oil/filter right before storing it. After 3 years the battery actually started the engine on the first crank. All I did was move the key to "on" until the fuel pump shut off which was a few seconds, and then turned it the rest of the way and it started right up. I also checked the tires and they were fine, probably because they had nitrogen in them. This was a Cobra Mustang with a rather pricey all aluminum DOHC engine that puts a docile 512rwhp to the rear tires. I drove it for about 45 minutes into town, ate lunch, and drove it around the rest of the day without going into boost or any heavy acceleration. The car was fine, I filled it back with premium, changed the oil, checked the tires again, checked the battery, and drove it for years after with no issues.

Same prep, back into storage 3 years later. It stayed that way for six years and I had a friend open my storage so my local Ford dealership could tow it back, drain the tank, new battery, tires, clutch, and a bunch of other work. But despite my friends protests they connected a jump pack, started it up and drove it to the dealership. Pissed me off, it wasn't what I asked for. They ended up replacing my injectors because the tank wasn't cleaned after six years and it should have been.

Both times the battery should have been fully charged before starting the car, using an alternator to charge a dead battery is a good way to kill the alternator.

I think at two years you'll be fine unless you stored it with ethanol. If you did, drain it all and flush the tank before starting. Not a bad idea to change the fuel filter. And for sure a new battery as old as yours is. For your coolant and brake fluid use test strips and change if needed. I've been using these test strips for years and they work pretty well. With ten year coolant that really lasts ten years you might not need to change and flush as often as you think.

[StephenVA]

Old fuel kills more pumps than hours of usage! Throw away the filter too!

[halfspec]

Thanks guys. Yes, like the OG post says, the fuel filter is getting replaced. I've got a spanking new MANN fuel filter on my bench waiting to go in

@SW530 - Yes. Unfortunately this was an unplanned event so it went into storage with ethonol mixed premium fuel so I'm resolved to move forward with draining + flushing the tank. Old fuel filter is off and I've got a new MANN ready to replace it. I was just looking for tips on how to get the fuel out on a e39. Looks like I need to prioritize my battery replacement so I can use it + a jumped fuel relay to force the fuel pump to pump it out
Coolant system is dry so no need for testing
Hydraulics line between my MC and the SC is dry so I'm going to be bleeding everything there anyway too. I think for brake fluid I'm going to err on the side of caution and flush the whole thing. I believe the service interval for brake fluid on the e39 is 2 years / 25k miles and I've had the car for 5 years without flushing it. I don't necessarily take that particular service interval as gospel, but I would be surprised it the car didn't have most of its OG fluid in the lines haha!

Lane

[halfspec]

Got an answer on the keyfob charging. Looks like I need to insert + turn the key to position 1 and leave it overnight with a trickle charger attached to the car battery.

Source = https://store.bimmernav.com/blogs/in...bmw-remote-key

Lane

[SW530]

It sounds like you have a handle on it. One thing though. The way Jim suggested to drain the tank is a good fast way to drain the tank, but I wouldn't use this method in your case because the fuel is so old and you'll want to pump it as dry as possible so you'll be draining all the crap through the pump and it's strainer.. unless you're going to replace the pump and strainer anyway I'd use another method.

I bought a Gas Tapper. There are 4-5 different models that will do the job, how easy and how fast is what separates the models and what you pay for them. The model I really wanted was too much money at the time so the squeeze ball model was good enough. It had the access lines and the case so I decided on that one for now and adding a pump in the future. I added this pump. It pumps faster than the gas tapper model and can be used alone if you can snake a line through the part of the fill tube designed so you can't get a bigger line down there. Screw it to a piece of wood for stability, connect some lines, away it goes for $19.99.. safe and you're not damaging anything.

IF you'll be flushing the tank anyway, and I highly recommend you do so, then just remove the fuel hat (under the rear seat, drivers side) and drop a regular fuel line down into the tank and vacuum up any sediment with the line. Once empty you can wipe out the bottom of the tank, or add fresh fuel and use the pump to vacuum up more sediment. This will give you the opportunity to inspect the pump strainer and replace if needed.

[halfspec]

I thought I'd bump this thread back vs starting a new one since I got a lot of good advice here.

I have a follow-up question about gas.

I ended up jumping out my fuel pump and pumping *all the gas out of my tank. I ran the pump until it changed tones and the gas stopped pumping out into my reclaim container. I checked it again later by jumping out the fuel pump (as a sanity check), and got maybe 16 ounces more... I was a little confused, but I felt like maybe it was just a little bit more gas back siphoning or finding its way back to the sump somehow. Anyway. I still felt pretty good about it, so I installed my new fuel filter and buttoned everything up. Finally, I put 5 gallons of new premium in for my first crank, testing, and my first drive to the gas station to fill up.
During my first crank and testing I noticed my fuel gauge was registering ~3/4ths of a tank which I thought was odd, but I thought it might have something to do with being disconnected from the battery for years and it might take some driving to realize there's only 5 gallons in the tank.

Well, I filled up my 540i last night for the first time in 2+ years (Yay!) but I was very surprised when the fill handle clicked at ~5 gallons! I thought it was just a false positive, but after another click and seeing the fuel pool up at the filler neck, I realized it was almost certainly truly full.

That would mean I didn't really succeed at fully draining my tank and I've got ~8 gallons of old fuel in there? Anyone have any ideas on where I messed up? I've heard there is a transfer pump somewhere in the mix. Is the gas tank in two sections and I just managed to drain one side because I didn't activate the transfer pump when I was draining the tank?

Lane

[JimLev]

It’s called a saddle tank with 2 sections.
The jet suction pump is suppose to move fuel from one section to the other section.
Your fuel level float may be stuck, a few bottles of Techron my help. Get the concentrated stuff for 20 gallons.

[halfspec]

Thanks Jim

I thought I'd remembered something about the tank being in two sections. That would make some sense out of that I was seeing. I'm guessing since I was only running my electric fuel pump to drain the tank and wasn't actually running the engine and putting vacuum on the jet suction pump, I only drained the fuel pump side of the saddle and the return side of the saddle kept its ~8 gallons of old gas?

If that's the case, I doubt my fuel level sender was ever wrong. It's registering as full after adding 5 gallons last night. I just think I'm running a 1:1 mix of new and 2 year old gas now. I guess I'll just take it easy and run through it with highway miles

Lane

[ross1]

1) Disconnect the fuel line from the filter, then jump the fuel pump relay. That will pump out the fuel in the tank.
2) I'd spray some fogging oil in thru all the spark plug holes, add oil to the filter housing, pull the fuel pump relay or fuse pulled, crank the engine until the oil light goes out.

This^^
You could, if the gas smells really foul*, after draining the tank and reconnecting the fuel line(to a new filter) run the pump again with the schrader on the fuel rail open, the hose for a pressure tester will do fine, to remove stale fuel from the line and rail.
* doubtful, fuel is NG at two years but probably not harmful.

[JimLev]

Halfspec, the jet suction pump doesn’t require engine vacuum. It’s using the flow from the fuel pump to pull fuel in from the other side of the tank.

[philly98540]

Use Test 6 to see fuel levels in each side of the tank.

[ross1]

Halfspec, the just suction pump doesn’t require engine vacuum. It’s using the flow from the fuel pump to pull fuel in from the other side of the tank.

Well and simply explained by this fellow here; https://www.youtube.com/watch?v=Na9ORhYjvJU

[halfspec]

This^^
You could, if the gas smells really foul*, after draining the tank and reconnecting the fuel line(to a new filter) run the pump again with the schrader on the fuel rail open, the hose for a pressure tester will do fine, to remove stale fuel from the line and rail.
* doubtful, fuel is NG at two years but probably not harmful.

Thanks ross1 - Sorry to waste your time on this since I've actually moved past these questions a couple of months ago and got the car fully back on the road recently - https://www.bimmerforums.com/forum/s...ing-and-Clutch
As for the jet suction pump, I wasn't having issues with understanding the venture venturi effect, but rather which jet suction pump we were talking about on the car (See my reply to Jim below). I appreciate the refresher though

Halfspec, the jet suction pump doesn’t require engine vacuum. It’s using the flow from the fuel pump to pull fuel in from the other side of the tank.

My bad. I just assumed we were talking about the jet venturi pump in the engine bay near the vac booster. I stacked assumptions not knowing the exactly how the engine bay pump is plumbed so I just figured the tank's transfer pump ran off of vacuum and the engine bay venturi pump ran it. Sorry for wasting your time Jim. I should have done my homework on this before posting.

Use Test 6 to see fuel levels in each side of the tank.

Excellent suggestion. I hurt my back over the weekend so I'm suspending work on my car for the week probably, but I'll be checking this out as soon as I get back to it to confirm my suspicion that I'm currently nearly full on both sides right now.

Just a recap on where I am for anyone still reading along:

1. May 26th 2022, I removed my fuel filter, back siphoned the gas leading to the injector manifold, then jumped out the fuel pump relay to pump my old fuel out of the tank and into a 5 gal container watching the level of my container + pump tone to decipher when the tank was empty. This is actual footage of the work and is approximately where I stopped because the fuel wasn't pumping anymore and the pump noise changed dramatically:



Also of note, the gas didn't stink and just smelled like regular gas. I had plans to dispose of it, but I ended up taking a risk and put it in my riding mower. I burnt it all with no issues.

2. On July 29th, after buttoning up the fuel system (new fuel filter + connected the fuel line to the injector manifold) I added 5 gallons of new gas to the car preemptively to prepare for my startup the next day. Prior to the startup I once again jumped out the fuel pump relay to prime the fuel lines and did this until my fuel pump changed its tone + 30s
3. Successfully cranked the car on July 30th - https://www.bimmerforums.com/forum/s...ing-and-Clutch
4. After wrapping up the rest of my loose ends, I took the car out for its second test drive and stopped at a gas station to do a 'full' fill-up with gas. I was only able to get 5 gallons in it before fuel started spilling out of the fuel neck. This is what caused me to revive this thread and caused me to state I believe I have 10 gallons of new gas in the tank + 8 gallons of old gas.

I have no idea why my procedure for jumping the fuel pump apparently didn't empty my fuel tank completely unless there's an issue with the fuel tank's jet suction pump which I've read is very unlikely. I don't know, maybe I did pump out my entire fuel pump, but for that to happen my fuel gauge would have to by lying and that would mean the fuel spilling out of my fuel filler neck was a bubble / fluke.

Barring better suggestions, my plan is to just drive the car until I'm close the empty per the fuel gauge. If I run out at 1/2 a tank I guess that would mean my jet pump is having issues, although I expect that's not the case and that a jet pump failure would be apparent much sooner since the fuel return goes to the side that supplies the jet pump right?

Lane

[JimLev]

Lane, your not wasting any of our time. It’s an educational thing for all that are reading your posts.
Check the level as Philly has suggested.
I’m guessing that your gravity draining from hose at the filter is why you didn’t all of the gas out from the other side of the saddle tank.
The fuel pump needs to run and pump fuel thru the jet suction pump in order to pull fuel from the other side or the tank.
You manually mostly drained the side that has the electric pump in it, then you powered the pump by jumping the relay. That finished pumping out what was left in the pump side of the tank AND stopped pulling fuel from the other side of the tank.

[philly98540]

Maybe the jet suck pump flow rate is normally a lot slower than the main fuel pump. I bet it is but have no numbers on that. If true, I bet you need to jump the main fuel pump with the full fuel system connected and monitor Test 6 to watch the fuel level in the driver side tank go down. The main fuel pump will circulate the full fuel pump rate and cause the jet suction pump to move the fuel to the passenger side. Once its all moved over, disconnect the fuel line and pump out the fuel to your container. Might take more than one shot if there is a lot of fuel in the tank(s).

Edit: Jim typed his response faster... damn I need to pick it up....

[halfspec]

You manually mostly drained the side that has the electric pump in it, then you powered the pump by jumping the relay. That finished pumping out what was left in the pump side of the tank AND stopped pulling fuel from the other side of the tank.

That's an amazing hypothesis and I fully expect you're correct.

I'll report back when I get my individual tank levels.

Thanks again everyone.
Lane

[halfspec]

Test6 = 17.6/31.0/48.6L
I’ve put about ~80 miles on the car since I filled it up. Gauge shows about 80% full.
No issues except my ~3yo tires are loud AF / road noisy or I’ve got a bad wheel bearing.
Guess I’ll keep driving and monitoring my levels 👍

Appreciate all the help
Lane

[Jason5driver]

I wouldn’t worry too much about the gas .
I would just put some fuel treatment in the tank , and you’re golden imo …
I’ve used this a lot , and it works great imo …
https://www.autozone.com/fuel-and-en...8oz/974763_0_0