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  #1  
Old 04-03-2012, 10:24 AM
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1978 300D fuel issue

Have a 78 300D with 110K miles, Drives slower and slower. My son was driving to school today and it got down to 15 mph (perfect!!!...no speeding tickets)

Anyhow, tonight I plan to check the tank screen, replace both fuel filters but I have read to check the ALDA (don't know what this is or what it looks like) Some post say the lift pump may be going bad, is this part of the injection pump? Where is it located. I will replace the rubber fuel lines and blow all lines clean etc. Will also check the primer pump to make sure no air is getting in. Had the problem a few yearss ago but would only happen after a few hours of driving, time between power loss is now getting shorter and shorter, now down to minutes so I'm assuming something is getting clogged. Two years ago I blew the lines clean and installed new filters but now the problem is back.

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  #2  
Old 04-03-2012, 10:29 AM
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Location: Nova Scotia, Canada.
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Leave the fuel tank cap loose for a test. The fuel tank vent may be obstructed causing a vacuum. Fuel filters are also a good possible candidate.
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  #3  
Old 04-03-2012, 10:33 AM
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I'll loosen the cap tonight and see what happens. My son is now driving my 190e that I just rebuilt the motor. Want him back in the 300d so it's nice and slow.
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  #4  
Old 04-03-2012, 11:17 AM
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Tank screen could be a likely cause of the problems. Check and clear all of the lines while you're at it (Supply,Return and Vent)

The lift pump is located on the drivers side front bottom of the Injection Pump. The hand primer pump is screwed into the top of it.

The lift pump is pretty durable but it can fail and could be causing the problems. Parts are available here.

Check valve rebuild kit = $8
complete rebuild kit = like $35 and three weeks delivery from Germany
New lift pump = like $180
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Current fleet
1992 300D "IceBerg"
1984 300D "Blues Mobile"

1978 300CD "El Toro" Gone on to be born again
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  #5  
Old 04-03-2012, 11:31 AM
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Is the vent line on the tank itself running up to the filler neck? Last time I was under the car (been awhile) I had two lines from the tank. Assuming one is fuel to the IP and the other is the return line. Not sure where the vent line is located. Maybe there are three lines?
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  #6  
Old 04-03-2012, 11:49 AM
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Three lines on the bottom side of the tank. One line on the screen side, that's the supply. Two on the other side. one is the return and the other is the vent. The vent line is short, comes up and ends right in front of the rear driver side wheel. Its got a lil rubber "horn" looking piece to keep the junk out.
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Current fleet
1992 300D "IceBerg"
1984 300D "Blues Mobile"

1978 300CD "El Toro" Gone on to be born again
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  #7  
Old 04-03-2012, 12:24 PM
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Location: Leiden, Netherlands
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Quote:
Originally Posted by 240diowa View Post
Anyhow, tonight I plan to check the tank screen, replace both fuel filters but I have read to check the ALDA (don't know what this is or what it looks like)
The 1978-300D does not have an ALDA, that is turbo-specific. It can have an ADA, which can restrict fuel if the air pressure is low (like when driving at altitude). It sits on top of the IP, round box.
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  #8  
Old 04-03-2012, 12:43 PM
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Should I check the ADA to make sure it is clean etc? Is there anything else I should check on the IP system assuming I have a clean strainer in the tank and I'm not sucking in air via the primer pump?
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  #9  
Old 04-04-2012, 01:22 AM
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Location: Out in the Boonies of Hot, Dry, Dusty, Windy Nevada
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You mentioned that 2 yrs ago you had the problem and changed the filters. now 2 yrs later same problem crops up. probably the filters again. how many miles since the last change?

You could swap the return and supply hose. run the cigar hose to the return line, (pipe) and return to where the cigar hose connects. (pipe) then your fuel supply will be drawn from the return side. If this restors you speed and power, then you night have a cloged fuel tank strainer.

When was the last time you adjusted the valves? adjusting them will make a difference. out of adj valves will also cause hard starting issues, especially in the cold winter months.

Do you have the new or old style primer pump. the old style, unscrew and pump, have been known to leak and suck air. new style (black) you just pump and nothing to unscrew.


Charlie
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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works
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  #10  
Old 04-04-2012, 01:40 PM
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Changed the filters, blew out the lines. Took the screen out of the tank (it was clean) Adjusted the fuel pressure regulator spring to 27 mm (it was around 20mm). runs great, lots more power. It does need a valve adjustment so will be doing that this weekend. To get the screen out I was able to use a tool they use to install hot water heater elements, fit great and only cost $4.00 (it was a tad too long so I trimmed it up with my chop saw) Way cheaper than buying a 47 mm socket if you can find one.
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  #11  
Old 08-14-2013, 11:09 AM
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Tank screen?

Hi There, I have a 78 300d as well and can't seem to find where the tank screen plugs in. it looks like the fuel line just goes in under the spare wheel housing. which is not what i am used to as i have had 2 newer 300d both 123 tho that didn't look like this. So i was just wondering if these older ones where different do you know? As i need to remove the screen if there is one to run on veggie oil. any idea?
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  #12  
Old 08-14-2013, 11:26 AM
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hose closest to the right side of the car. Aproximately just above the right side of the diferential/Axle. 6"-8" piece of hose coming out then atached to the hardline.
__________________
Current fleet
1992 300D "IceBerg"
1984 300D "Blues Mobile"

1978 300CD "El Toro" Gone on to be born again
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  #13  
Old 08-14-2013, 04:47 PM
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Quote:
Originally Posted by Ashley05 View Post
Hi There, I have a 78 300d as well and can't seem to find where the tank screen plugs in. it looks like the fuel line just goes in under the spare wheel housing. which is not what i am used to as i have had 2 newer 300d both 123 tho that didn't look like this. So i was just wondering if these older ones where different do you know? As i need to remove the screen if there is one to run on veggie oil. any idea?
Oh god really? A one tank wvo car....well guess there will be another one in the junkyard....if it has black seats, I need some skins...
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  #14  
Old 08-15-2013, 01:39 PM
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Location: Long Beach,CA
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Quote:
Originally Posted by Phillytwotank View Post
Tank screen could be a likely cause of the problems. Check and clear all of the lines while you're at it (Supply,Return and Vent)

The lift pump is located on the drivers side front bottom of the Injection Pump. The hand primer pump is screwed into the top of it.

The lift pump is pretty durable but it can fail and could be causing the problems. Parts are available here.

Check valve rebuild kit = $8
complete rebuild kit = like $35 and three weeks delivery from Germany
New lift pump = like $180
If you get the Check Valve Kit and scrounge up the 5mm O-ring that seals the Piston Push Rod you have all you need to do a rebuild.
The only thing that is lacking is the Copper Crush Washer the seals the Big Plug on the Fuel Supply/Lift Pump.
The Plug does not need to be removed to do the rebuild of the Lift Pump.

However, I like to remove that Plug to inspect the Piston and the Piston Spring.
When I did that and had no new Crush Washer I simply used some blue Loctite on the last 2 or 3 threads that are next to the head of the Plug.

Some sources of the O-ring are in the DIY Threads
DIY Repair Links
http://www.peachparts.com/shopforum/forumdisplay.php?f=82
http://www.peachparts.com/Wikka/DoItYourSelf
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84 300D, 82 Volvo 244Gl Diesel
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  #15  
Old 08-15-2013, 01:43 PM
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Quote:
Originally Posted by 240diowa View Post
Changed the filters, blew out the lines. Took the screen out of the tank (it was clean) Adjusted the fuel pressure regulator spring to 27 mm (it was around 20mm). runs great, lots more power. It does need a valve adjustment so will be doing that this weekend. To get the screen out I was able to use a tool they use to install hot water heater elements, fit great and only cost $4.00 (it was a tad too long so I trimmed it up with my chop saw) Way cheaper than buying a 47 mm socket if you can find one.
Which one of the above do You think fixed the problem?

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84 300D, 82 Volvo 244Gl Diesel
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