1984 Benz 380SL won't start...
08-02-2009, 05:36 AM
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1984 Benz 380SL won't start...
I inherited a 1984 Mercedes-Benz 380SL from my grandparents. Nice folks, huh?
There is a catch, however...
The car does not start.
The starter actuates and the engine turns over, but fails to fire. I do not hear the electronic fuel pump pressurizing upon turning on the accessories w/ the key.
My question is: Do you always hear the fuel system pressurize when you put the key in and turn it to accessory mode?
There is a catch, however...
The car does not start.
The starter actuates and the engine turns over, but fails to fire. I do not hear the electronic fuel pump pressurizing upon turning on the accessories w/ the key.
My question is: Do you always hear the fuel system pressurize when you put the key in and turn it to accessory mode?
08-02-2009, 05:40 AM
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Re: 1984 Benz 380SL won't start...
Ha, a fellow 80s Benz fan.
There's a guy in Cpeake who is very good with Benzes (he may be moving, I'll find out) and always willing to help out a fellow fan. (I know them too, but I'm all the way up in Williamsburg)
That car looks real cherry.
There is a way to jump the fuel pump relay - that's usually the issue with this problem. I wanted to post while you're still online. Standby and I'll have the answer for you in two minutes.
OK, here's what it is - go to the fuse box, yank out the fuel pump relay (black box about the size of a pack of cigarettes, only thiicker, should say 5500rpm on the side of it somewhere to indicate the redline) and jump slots 30 and 87 with a wire - if it starts, your problem is the fuel pump relay.
There's a guy in Cpeake who is very good with Benzes (he may be moving, I'll find out) and always willing to help out a fellow fan. (I know them too, but I'm all the way up in Williamsburg)
That car looks real cherry.
There is a way to jump the fuel pump relay - that's usually the issue with this problem. I wanted to post while you're still online. Standby and I'll have the answer for you in two minutes.
OK, here's what it is - go to the fuse box, yank out the fuel pump relay (black box about the size of a pack of cigarettes, only thiicker, should say 5500rpm on the side of it somewhere to indicate the redline) and jump slots 30 and 87 with a wire - if it starts, your problem is the fuel pump relay.
Last edited by marlinspike; 08-02-2009 at 05:44 AM.
08-02-2009, 05:44 AM
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Re: 1984 Benz 380SL won't start...
Thrifty. Thank you much. I will give it a shot...
Last edited by Thestearninator; 08-02-2009 at 05:47 AM.
08-02-2009, 05:46 AM
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Re: 1984 Benz 380SL won't start...
Here's mine btw
Started life as a 1985 380SE. Now it has a euro 560 engine with high compression pistons, lumpy cams, headers, some other things (so, don't worry, we'll get this thing started...even if it means my having to make a trip down).
Are you in the MBCA? The local chapter has very knowledgeable people in it. A lot of older rich guys, but they aren't afraid to get their hands dirty.
Oh, and yes, on the pre-1986 cars you should hear the fuel pump pressurize when you turn the key to the start position.
If it does turn out to be the FPR, this is unfortunately one part where the aftermarket ones are no good. You either have to shell out for an MB branded one or you can see if http://www.beckmanntechnologies.com/ has one (they're good rebuilds, though sometimes they cost as much as a new MB branded one).
Started life as a 1985 380SE. Now it has a euro 560 engine with high compression pistons, lumpy cams, headers, some other things (so, don't worry, we'll get this thing started...even if it means my having to make a trip down).
Are you in the MBCA? The local chapter has very knowledgeable people in it. A lot of older rich guys, but they aren't afraid to get their hands dirty.
Oh, and yes, on the pre-1986 cars you should hear the fuel pump pressurize when you turn the key to the start position.
If it does turn out to be the FPR, this is unfortunately one part where the aftermarket ones are no good. You either have to shell out for an MB branded one or you can see if http://www.beckmanntechnologies.com/ has one (they're good rebuilds, though sometimes they cost as much as a new MB branded one).
Last edited by marlinspike; 08-02-2009 at 05:52 AM.
08-02-2009, 05:52 AM
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Re: 1984 Benz 380SL won't start...
Nice car. Expensive to build the engine?
By the way, I'm looking at the fuse panel near the passenger floorboard and I don't see the relay. Any pointers?
Also, I might add... This is my first Benz and my first car manufactured prior to 1994 - so this old technology is going to take a bit of getting used to.
I literally received the automobile yesterday, so I've not yet had the chance to network with any locals on these vehicles.
By the way, I'm looking at the fuse panel near the passenger floorboard and I don't see the relay. Any pointers?
Also, I might add... This is my first Benz and my first car manufactured prior to 1994 - so this old technology is going to take a bit of getting used to.
I literally received the automobile yesterday, so I've not yet had the chance to network with any locals on these vehicles.
Last edited by Thestearninator; 08-02-2009 at 05:56 AM.
08-02-2009, 05:57 AM
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Re: 1984 Benz 380SL won't start...
Lol, yes, very expensive to build the engine. Stupid really, but worth it to me.
Check behind the glovebox, IIRC on the SLs they put some things there too.
BTW, since it's a 1984 model, at some point take the valve cover off and make sure you have a dual-row timing chain. Until some time in 1984 MB was using a single row chain in the US, and they had a way of breaking (this is an interference engine). I know back in the day they were retro-fitting them to the dual row for free. I think now they make you pay some of the cost.
The old technology is great. You know what the factory service manual says to do when the O2 sensor light comes on? It says to take the instrument cluster out and remove the bulb. It was just a trip wire that came on when the odometer hit 60,000 miles lol. Mine currently has a bad idle control unit in it (saving up for a new one, ugh). When it goes to high idle, I just pop the hood and hit the idle control unit with a lug wrench and it goes back down lol.
EDIT: Hey, you know what, I just remembered I have an SL factory service manual on my other hard drive, I'll just pop that in and tell you where the relay is...
Check behind the glovebox, IIRC on the SLs they put some things there too.
BTW, since it's a 1984 model, at some point take the valve cover off and make sure you have a dual-row timing chain. Until some time in 1984 MB was using a single row chain in the US, and they had a way of breaking (this is an interference engine). I know back in the day they were retro-fitting them to the dual row for free. I think now they make you pay some of the cost.
The old technology is great. You know what the factory service manual says to do when the O2 sensor light comes on? It says to take the instrument cluster out and remove the bulb. It was just a trip wire that came on when the odometer hit 60,000 miles lol. Mine currently has a bad idle control unit in it (saving up for a new one, ugh). When it goes to high idle, I just pop the hood and hit the idle control unit with a lug wrench and it goes back down lol.
EDIT: Hey, you know what, I just remembered I have an SL factory service manual on my other hard drive, I'll just pop that in and tell you where the relay is...
Last edited by marlinspike; 08-02-2009 at 06:00 AM.
08-02-2009, 05:59 AM
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Re: 1984 Benz 380SL won't start...
I've read that the timing chains can be the death of these engines. Hopefully I've got a dual-row chain... The valve cover gaskets look like they need to be changed, so I need to get in there anyway.
08-02-2009, 06:03 AM
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Re: 1984 Benz 380SL won't start...
Ah crap, my bad - the service manuals I have on CD are only for the 126, not the 107 (126 is like mine, 107 is the SL)
OK, but yeah, it's behind the glovebox. You should have two relays back there, one that says Klima (for the climate control) and the other will say 8zly and should say the redline on it (that's the fuel pump relay).
OK, but yeah, it's behind the glovebox. You should have two relays back there, one that says Klima (for the climate control) and the other will say 8zly and should say the redline on it (that's the fuel pump relay).
08-02-2009, 06:12 AM
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Re: 1984 Benz 380SL won't start...
No, just the glovebox liner. Should be held in with 8 2-piece snaps if it's like the 126 (I don't remember for sure) you take out the top piece that fits inside the lower piece and then you can take the lower piece out.