380Sl Won't stay idling - Page 2 - Mercedes-Benz Forum
Reply
 
LinkBack Thread Tools Display Modes
post #11 of 36 (permalink) Old 02-16-2019, 07:42 PM Thread Starter
BenzWorld Junior Member
 
Date registered: Mar 2014
Vehicle: 1975 450SL, 1982 380SL, 1995 SL320
Location: Ewa Beach, Hawaii
Posts: 35
Mentioned: 0 Post(s)
Quoted: 11 Post(s)
Garage
(Thread Starter)
Thanks. Tomorrows project for sure.
BTW, I like your project car. I have a 75 450SL project myself lol.
Riggmaster is offline  
Sponsored Links
Advertisement
 
post #12 of 36 (permalink) Old 02-16-2019, 07:47 PM
Lifetime Premium Member
 
Date registered: Sep 2015
Vehicle: 1976 450SL
Location: CT, USA
Posts: 336
Mentioned: 2 Post(s)
Quoted: 68 Post(s)
Lifetime Premium Member
Quote:
Originally Posted by Riggmaster View Post
Thanks. Tomorrows project for sure.
BTW, I like your project car. I have a 75 450SL project myself lol.
Thanks...can't wait for the weather to warm up so I can get out to the garage and start work on it again. I'm really hoping to have it back on road this year.
Riggmaster likes this.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

'76 450SL 'Yard Find' Project
TheFixer is online now  
post #13 of 36 (permalink) Old 02-17-2019, 09:53 PM Thread Starter
BenzWorld Junior Member
 
Date registered: Mar 2014
Vehicle: 1975 450SL, 1982 380SL, 1995 SL320
Location: Ewa Beach, Hawaii
Posts: 35
Mentioned: 0 Post(s)
Quoted: 11 Post(s)
Garage
(Thread Starter)
Couldn’t quite do that testing because I would fill a 5 gallon jug before it would normally start acting bad.

Back to the return tube connected to the tank. I connected compressed air to that tube and no air went through. Tomorrow I’m removing the tank and getting to the bottom of this.
Riggmaster is offline  
Sponsored Links
Advertisement
 
post #14 of 36 (permalink) Old 02-17-2019, 09:56 PM Thread Starter
BenzWorld Junior Member
 
Date registered: Mar 2014
Vehicle: 1975 450SL, 1982 380SL, 1995 SL320
Location: Ewa Beach, Hawaii
Posts: 35
Mentioned: 0 Post(s)
Quoted: 11 Post(s)
Garage
(Thread Starter)
Quote:
Originally Posted by frazierfrazier View Post
Have you inspected the tank? I know you said you blew out the fuel lines, but I would check to see if there’s corrosion in your tank. You can take a peek by removing the fuel sender in the soft top stow away compartment. Requires a 48mm socket if I remember correctly.

I Will inspect it 100% tomorrow when I take the tank out of the car.
Riggmaster is offline  
post #15 of 36 (permalink) Old 02-18-2019, 05:16 AM
Premium Member
 
Jyuma's Avatar
 
Date registered: May 2017
Vehicle: 1983 380 SL
Location: Long Island, New York USA
Posts: 1,956
Mentioned: 13 Post(s)
Quoted: 702 Post(s)
Premium Member
Garage
I'm a little late to this party but on my '83 380sl I had a clogged return line that I cleared by spraying carburator cleaner into the return line from the engine compartment and using moderate compressed air to force it down the line. After doing that several times I cranked up the pressure and this is what came out of the line at the back (obviously I removed the return line at the tank and directed it into the bucket).

380Sl Won't stay idling-mercreturnfuellinecrap1.jpg



You can easily test to see if the return is indeed clogged by pushing on the air flow metering plate just after it stalls. If the return is clogged the air flow plate will be noticeably stiff and resist being pushed down by hand.

Nobody gets out of this life alive.
Jyuma is online now  
post #16 of 36 (permalink) Old 02-18-2019, 09:27 AM Thread Starter
BenzWorld Junior Member
 
Date registered: Mar 2014
Vehicle: 1975 450SL, 1982 380SL, 1995 SL320
Location: Ewa Beach, Hawaii
Posts: 35
Mentioned: 0 Post(s)
Quoted: 11 Post(s)
Garage
(Thread Starter)
Quote:
Originally Posted by Jyuma View Post
I'm a little late to this party but on my '83 380sl I had a clogged return line that I cleared by spraying carburator cleaner into the return line from the engine compartment and using moderate compressed air to force it down the line. After doing that several times I cranked up the pressure and this is what came out of the line at the back (obviously I removed the return line at the tank and directed it into the bucket).

Attachment 2490364



You can easily test to see if the return is indeed clogged by pushing on the air flow metering plate just after it stalls. If the return is clogged the air flow plate will be noticeably stiff and resist being pushed down by hand.
I did notice the sensor plate appeared “stiff” after stalling. There was also a whining sound from intake when I pushed it down.

I did remove the return line in the engine compartment as well as disconnecting the short hose on the other end of that line in the rear., and blew compressed air. Everything is clear except the short line leading to the tank. With 3 cans of carb cleaner and using a 12 gauge insulated copper wire I was able to push a clear path up to 18.75 inches. That’s where it stops.🤔
Riggmaster is offline  
post #17 of 36 (permalink) Old 02-18-2019, 10:05 AM
Premium Member
 
Jyuma's Avatar
 
Date registered: May 2017
Vehicle: 1983 380 SL
Location: Long Island, New York USA
Posts: 1,956
Mentioned: 13 Post(s)
Quoted: 702 Post(s)
Premium Member
Garage
Quote:
Originally Posted by Riggmaster View Post
I did notice the sensor plate appeared “stiff” after stalling. There was also a whining sound from intake when I pushed it down.

I did remove the return line in the engine compartment as well as disconnecting the short hose on the other end of that line in the rear., and blew compressed air. Everything is clear except the short line leading to the tank. With 3 cans of carb cleaner and using a 12 gauge insulated copper wire I was able to push a clear path up to 18.75 inches. That’s where it stops.🤔
Two years ago I authored a lengthy thread on restoring the fuel tank in my '83 380sl. Many in this forum much wiser than me suggested that I replace the tank instead of attempting to restore it. They were right... two weeks ago I finally ordered a replacement tank.
Riggmaster and okyoureabeast like this.

Nobody gets out of this life alive.
Jyuma is online now  
post #18 of 36 (permalink) Old 02-18-2019, 01:54 PM
BenzWorld Elite
 
Djenka018's Avatar
 
Date registered: Jan 2005
Vehicle: '80 450SLC Afro RHD Ikonengold
Location: ɹǝpu∩ uʍop 'ʎǝupʎS
Posts: 2,670
Mentioned: 2 Post(s)
Quoted: 121 Post(s)
Quote:
Originally Posted by Jyuma View Post
...
You can easily test to see if the return is indeed clogged by pushing on the air flow metering plate just after it stalls. If the return is clogged the air flow plate will be noticeably stiff and resist being pushed down by hand.
Are you sure about this?

To my knowledge this is normal behaviour supported by the special valves in the FD and Fuel accumulator both designed to maintain FD back pressure (WUR pressure) above 2 bar for some time(about 1/2 hr) after system pressure drops, to facilitate acceptable hot restart.

On my car with a perfect starting engine (now), the baffle plate is real stiff for about 1hr (new fuel accu, WUR return valve seal good) and soft overnight (WUR control pressure falls to 0bar).

From my understanding and readings on the K-Jet and KA-Jet, clogged return line, in addition to faults from excessive system pressure and severe noise from the fuel pump labouring, could cause lean condition through increased back pressure on the WUR thus higher control pressure

.
Vitamin C for SL... the SLC
Djenka018 is online now  
post #19 of 36 (permalink) Old 02-18-2019, 02:16 PM
Premium Member
 
Jyuma's Avatar
 
Date registered: May 2017
Vehicle: 1983 380 SL
Location: Long Island, New York USA
Posts: 1,956
Mentioned: 13 Post(s)
Quoted: 702 Post(s)
Premium Member
Garage
Quote:
Originally Posted by Djenka018 View Post
Are you sure about this?

To my knowledge this is normal behaviour supported by the special valves in the FD and Fuel accumulator both designed to maintain FD back pressure (WUR pressure) above 2 bar for some time(about 1/2 hr) after system pressure drops, to facilitate acceptable hot restart.

On my car with a perfect starting engine (now), the baffle plate is real stiff for about 1hr (new fuel accu, WUR return valve seal good) and soft overnight (WUR control pressure falls to 0bar).

From my understanding and readings on the K-Jet and KA-Jet, clogged return line, in addition to faults from excessive system pressure and severe noise from the fuel pump labouring, could cause lean condition through increased back pressure on the WUR thus higher control pressure
When my return line was clogged I couldn't move the air flow plate down at all, it was like it was glued shut. Under normal conditions with normal return pressure you can press the plate down and you can here the injectors spraying fuel. Mine wouldn't go down at all until I let the pressure bleed down. From the looks of the muck that eventually came out of my return line, you can understand why. The dried decomposed fuel that was in the line actually took on the shape of the tube. It looked like long black worms were shot out of the line. Here's a close up of the mess that exploded into the bucket from the return line.

380Sl Won't stay idling-mercreturnfuellinecrap2.jpg

Nobody gets out of this life alive.
Jyuma is online now  
post #20 of 36 (permalink) Old 02-18-2019, 04:30 PM
BenzWorld Elite
 
okyoureabeast's Avatar
 
Date registered: Mar 2017
Vehicle: 1984 380SL
Location: North America
Posts: 1,783
Mentioned: 6 Post(s)
Quoted: 595 Post(s)
Quote:
Originally Posted by Jyuma View Post
That looks like the goo from that Aliens prequel movie that turned everything into aliens.
Nothing a little techron wouldn't fix.

So... did you touch it?
okyoureabeast is offline  
Sponsored Links
Advertisement
 
Reply

  Mercedes-Benz Forum > Mercedes-Benz Roadster Forums > R/C107 SL/SLC Class

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Mercedes-Benz Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Topic Author Forum Replies Last Post
Rear Stabilizer/Sway Bar Links on 380SL and 560SL ... cwmoser R/C107 SL/SLC Class 0 02-09-2019 10:30 AM
my 380sl wont stay running!!!!! fabjim975 R/C107 SL/SLC Class 3 07-23-2011 12:14 PM
Rough Idling leesan W124 E,CE,D,TD Class 7 03-22-2010 08:38 AM
Idling rpm on an automatic – exactly what IS idling? Saloon W201 190-Class 31 02-28-2010 03:00 AM
Idling trouble fullframe731 W124 E,CE,D,TD Class 3 02-08-2008 09:55 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 

Title goes here

close
video goes here
description goes here. Read Full Story
For the best viewing experience please update your browser to Google Chrome