Filled GL350 with unleaded rather than diesel
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Member
Joined: Apr 2016
Posts: 142
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2013 GL350
Filled GL350 with unleaded rather than diesel
I majorly messed up!!! Without thinking I filled my GL
350 with unleaded rather than diesel. The truck was running while I was filling. After I filled it and as soon as I sat in the seat, I noticed it was idling rough and
immediately realized I messed up and turned it off. I had it towed to a local shop that services diesel cars/trucks etc but they were uncomfortable working on a benz. The local MB indie I do use does not work on diesel engines. I located another indie but he did not have a way to dispose of the fuel so I had it towed to the dealership. The dealership wants to approach this in two phases. 1) drain the fuel, change the filter, drop the tank and change all of the fuel pumps -3? for $7,500. If that doesn’t work then proceed to Phase 2 for an ADDITIONAL $20,000 - not sure what they were going to do as the $20k stopped me from listening. The way I look at it, I have the following options:
1) call it a day and send it on its way and chalk it up to my stupidity
2) roll the dice on the $7500 repair
3) try to find another indie although these look to be high end repair shops with slightly less hourly rate ($170 ish vs $260 dealer)
4) try to find another diesel facility that perhaps would be willing to work on a benz
5) make it a project car, bring it home and pretend I could muddle my way through the first phase.
any other ideas? I appreciate your feedback
I also posted this to the diesel forum.
350 with unleaded rather than diesel. The truck was running while I was filling. After I filled it and as soon as I sat in the seat, I noticed it was idling rough and
immediately realized I messed up and turned it off. I had it towed to a local shop that services diesel cars/trucks etc but they were uncomfortable working on a benz. The local MB indie I do use does not work on diesel engines. I located another indie but he did not have a way to dispose of the fuel so I had it towed to the dealership. The dealership wants to approach this in two phases. 1) drain the fuel, change the filter, drop the tank and change all of the fuel pumps -3? for $7,500. If that doesn’t work then proceed to Phase 2 for an ADDITIONAL $20,000 - not sure what they were going to do as the $20k stopped me from listening. The way I look at it, I have the following options:
1) call it a day and send it on its way and chalk it up to my stupidity
2) roll the dice on the $7500 repair
3) try to find another indie although these look to be high end repair shops with slightly less hourly rate ($170 ish vs $260 dealer)
4) try to find another diesel facility that perhaps would be willing to work on a benz
5) make it a project car, bring it home and pretend I could muddle my way through the first phase.
any other ideas? I appreciate your feedback
I also posted this to the diesel forum.
Junior Member
Joined: Mar 2013
Posts: 69
Likes: 13
From: SE Pennsylvania
07 C280 4matic, 2014 GL450, 91 VW Vanagon
Find someone to pump out, drain, siphon, etc. the fuel out ot the tank. Put a couple of gallons of diesel in it to dilute the residual. Drain or otherwise remove then put in diesel. i'm not familiar with the MB fuel pump, If it has an electric pump to pump to the injection pump, disconnect at the injection pump and run the pump to purge the gasoline from the fuel line. You want to get all the gasoline out of the fuel tank and lines before the injecdtion pump so that the minute it starts it has diesel fuel to lubricate the pump. Start it, let it idle for a minute to circulate the fuel before driving. It's not the end of the world Itd happens every day. If an everyday mechanic can't figure this out, they're not much of a mechanic.
You could always try an indy that services MB diesel truck. You want someone that doesn't need the OBDII port to tell them what to do.
You could always try an indy that services MB diesel truck. You want someone that doesn't need the OBDII port to tell them what to do.
MBWorld Fanatic!
Joined: Jun 2014
Posts: 1,086
Likes: 443
From: Melbourne, Australia
2010 ML550 VIN WDC1641722A564750, 2010 B180
If it's going to cost you $7500, then what's the harm in trying @acetaylor advice? It's exactly what a good mechanic would do, before loading the parts cannon and running you up a bill you probably don't need to do anyway. Chances are you've done no material damage if you only ran it for a few seconds.
MBWorld Fanatic!
Joined: Oct 2019
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From: Colorado
G550
Don't ever fill your fuel tank with your engine running, regardless of it being diesel or gasoline. You might have little regard for your own life, but the guy fueling up next to you probably thinks differently about his.
Member
Joined: Aug 2016
Posts: 126
Likes: 47
From: Toronto
2013 Mercedes GL350 Bluetec (X166) & 2019 Mercedes A220 (W177) & Retired 2008 Mercedes C300 (W204)
This is one of my biggest fears of putting regular gas vs diesel. I always fill the GL, no one else, call it trust issues but I'd rather not have to deal with it. With the infrequent fills I do, mostly monthly, its like a "Treat" to go fill up 
Based on the feedback, I would follow @BlownV8 recommendations. You would have already had diesel in the tank when filling so the regular fuel got diluted, how much depends on how much you had before filling up. This would make the most sense and most cost effective. It may run a bit rough initially but once it's back to full diesel, should smooth out.
Based on the feedback, I would follow @BlownV8 recommendations. You would have already had diesel in the tank when filling so the regular fuel got diluted, how much depends on how much you had before filling up. This would make the most sense and most cost effective. It may run a bit rough initially but once it's back to full diesel, should smooth out.
Senior Member
Joined: Nov 2018
Posts: 267
Likes: 65
From: Hampshire , UK
2015 S500, 2016 GL63 AMG
In the UK we have " fuel doctors " or whatever they want to call themselves, I had to call one out when i put £50 of petrol in my diesel jaguar about 10 years ago,
Great service, he disconnected the fuel line , then pumped the petrol out( sucked it i guess ), then when it was virtually empty he changed the filter and asked me to start refilling with diesel.
He carried on sucking it through for a couple of gallons and then reconnected the pipe.
All in all it took maybe an hour at most. They have a fixed price if all goes to plan, it was about £300 including a sunday night call out at 8pm .
I was really pleased and gave him some extra as well.
I was 50 miles from home !!
Great service, he disconnected the fuel line , then pumped the petrol out( sucked it i guess ), then when it was virtually empty he changed the filter and asked me to start refilling with diesel.
He carried on sucking it through for a couple of gallons and then reconnected the pipe.
All in all it took maybe an hour at most. They have a fixed price if all goes to plan, it was about £300 including a sunday night call out at 8pm .
I was really pleased and gave him some extra as well.
I was 50 miles from home !!
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MBWorld Fanatic!
Joined: Jan 2016
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From: In the Shadow of the Tetons
2013 ML350 Bluetec
I did this once with my '05 chevy duramax in North Carolina. I live in Idaho.
Did you know that some fuel filler handles that are green are not diesel? I do too, now.
I put about 10 gallons of unleaded fuel (FROM A GREEN HANDLE!!!) on top of about 10 gallons of diesel in a 30 gallon tank. Stopped as soon as I noticed what was happening. Limped the truck about 5 miles to my destination, siphoned off about 15 gallons of the fuel mix into 3 brand new 5 gallon fuel jugs I bought just for the purpose. Filled the tank with diesel fuel and an ungodly amount of treatment. Drove warily for the next few tanks of fuel, thinking that my intake manifold would surely explode at any second. It didn't. Made it 2500 miles home with out issue, and the truck - which had 160K miles on it at the time - now has about 333,500 miles on it and is currently towing the camper I'm typing this post from on a 1200 mile trip.
Drain the fuel, flush it if you must, treat the new (correct) fuel with plenty of lubricity, and drive it.
Did you know that some fuel filler handles that are green are not diesel? I do too, now.
I put about 10 gallons of unleaded fuel (FROM A GREEN HANDLE!!!) on top of about 10 gallons of diesel in a 30 gallon tank. Stopped as soon as I noticed what was happening. Limped the truck about 5 miles to my destination, siphoned off about 15 gallons of the fuel mix into 3 brand new 5 gallon fuel jugs I bought just for the purpose. Filled the tank with diesel fuel and an ungodly amount of treatment. Drove warily for the next few tanks of fuel, thinking that my intake manifold would surely explode at any second. It didn't. Made it 2500 miles home with out issue, and the truck - which had 160K miles on it at the time - now has about 333,500 miles on it and is currently towing the camper I'm typing this post from on a 1200 mile trip.
Drain the fuel, flush it if you must, treat the new (correct) fuel with plenty of lubricity, and drive it.
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Thread Starter
Member
Joined: Apr 2016
Posts: 142
Likes: 23
2013 GL350
Update - towed it back to house and found a local mobile mechanic that had done this with several other brands. Apparently it happens often enough. We dropped the exhaust, dropped the drivetrain and dropped the tank. Drained and cleaned the tank by removing one of the fuel pumps. Tested the pump and it worked. Put it back together, put some fresh diesel in and purged the line from the tank to the filter and the line from the filter to the HP pump. Built the pressures up by cycling car on and off about 6 times without starting. Car then turned over on third attempt but fired up. Ran rough for about 15 seconds then purred like kitten. Ran around, filled the tank with diesel and have put about 40 miles on and all is good. In hindsight, probably would have ordered a new pump locking ring and seal as it appears we have a leak now. So I get to drop everything and put new seal and lid all…..oh well, still glad no damage done. Thanks again for all the feedback.
