Advice needed 1980 380E

[alabbasi]

Not necessarily, any UK Mercedes with CIS after 1984 generally has twin pumps. Some models had it earlier, some later, although it could be a USA vs UK market difference.

I do envy the climate you guys have the other side of the pond, I have friends in Arizona who are shocked at how bad some UK cars get underneath.

For example? I'd be interested to know as I've owned several non US spec cars (4, 6 and V8) and none had twin pumps.

A friend of mine has a E300TD Wagon (OM603 turbo) that he mated a 722.6 5 speed automatic. It pretty much transformed the way the car rove. He also had an E300D with an OM606. For a diesel, it revs. It's not turbo fast, but I wouldn't call it slow.

 

[carat 3.6]

For example? I'd be interested to know as I've owned several non US spec cars (4, 6 and V8) and none had twin pumps.

A friend of mine has a E300TD Wagon (OM603 turbo) that he mated a 722.6 5 speed automatic. It pretty much transformed the way the car rove. He also had an E300D with an OM606. For a diesel, it revs. It's not turbo fast, but I wouldn't call it slow.

Any w126 from a 300 to 560.

W201 and W124 from a 260 upwards.

W123 and R107 280's upwards, not sure on the 4cyl versions.

This video shows the twin pump setup on a W126:

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But again it could be market differences, Pontooner's mention about the quad downpipes being a good example of that. I think my American freinds call those "tri y headers", standard on a UK car whereas it seems to be rare on a US car.

 

[alabbasi]

Any w126 from a 300 to 560.

W201 and W124 from a 260 upwards.

W123 and R107 280's upwards, not sure on the 4cyl versions.

This video shows the twin pump setup on a W126:

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But again it could be market differences, Pontooner's mention about the quad downpipes being a good example of that. I think my American freinds call those "tri y headers", standard on a UK car whereas it seems to be rare on a US car.

That's what I thought (and I apologize up front for geeking out).

From 86 model year onwards, those cars CIS-E (or KE Jetronic) not CIS. It's a different system that looks similar, but is different. The M110 280SL was only available with d-jetronic in the very early years and CIS from 76 to 85 when the engine was replaced with the M103 which had CIS-E.

All cars with the M110 had a single pump (I owned a Euro 280CE and currently have two 280SLs with CIS and a 72 280CE with D-jet).

I'm pretty sure the M103 300 (CIS-E) motor had a single pump as i've owned a couple, but it's been some time so I could be wrong. The M116 4.2 V8 (CIS-E) has a single pump. My 84 (Euro) 500SL uses a single (CIS) but my two 560's have twin pumps.

The main outward difference under the bonnet of a US vs Euro car is the exhaust systems. The US cars with the V8 engines have manifolds that go into a single pre cat behind the engine before going to a secondary cat under the car. The Euro cars will have a full dual exhaust system. Some of which are logs and others are Tri Y. My US 560SEC has logs and I owned a Euro 500SEC (gen 2, CIS-E car) which had Tri Y. Some people suggest that the Tri Y's were only available on the 300HP 560 engines, but EPC says that my Euro 560 is a 300hp car and it has logs. To my knowledge, the twin pump setup was only introduced with CIS-E was introduced from 85/86 to 92 with the last M119 CIS-E cars in the R129 500SL. I have not seen it on anything other than M117 560's and M119 500's. but as you mentioned, you had other models that were not available in the US that might have had CIS-E and twin pumps. I very much doubt that there were any CIS Mercedes with twin pumps and I'm going to assume that anything with a carburetor is going to only need a single pump as carbs rarely need anything more than 5-7psi of fuel pressure. My 7.7 liter Cadillac uses a mechanical pump driven off the camshaft and it feeds it plenty (PLENTY) of fuel.

Going back on topic for the OP. If the you're getting fuel at a rate of 1 liter every 30 seconds. Your pump is healthy. That's a pretty thick diameter pipe to the FD so you're not going to get high pressure with it removed, you'll get high flow. I suspect that the piston may be stuck in the fuel distributor which is preventing fuel from getting to the injectors. You can crack lines open on top of the fuel distributor that go to the injectors and see if they bleed fuel. If you have fuel going into the FD and no fuel going out of the FD, you know it's the FD.

 

[carat 3.6]

From 86 model year onwards, those cars CIS-E (or KE Jetronic) not CIS. It's a different system that looks similar, but is different. The M110 280SL was only available with d-jetronic in the very early years and CIS from 76 to 85 when the engine was replaced with the M103 which had CIS-E.

All cars with the M110 had a single pump (I owned a Euro 280CE and currently have two 280SLs with CIS and a 72 280CE with D-jet).

I'm pretty sure the M103 300 (CIS-E) motor had a single pump as i've owned a couple, but it's been some time so I could be wrong. The M116 4.2 V8 (CIS-E) has a single pump. My 84 (Euro) 500SL uses a single (CIS) but my two 560's have twin pumps.

The main outward difference under the bonnet of a US vs Euro car is the exhaust systems. The US cars with the V8 engines have manifolds that go into a single pre cat behind the engine before going to a secondary cat under the car. The Euro cars will have a full dual exhaust system. Some of which are logs and others are Tri Y. My US 560SEC has logs and I owned a Euro 500SEC (gen 2, CIS-E car) which had Tri Y. Some people suggest that the Tri Y's were only available on the 300HP 560 engines, but EPC says that my Euro 560 is a 300hp car and it has logs. To my knowledge, the twin pump setup was only introduced with CIS-E was introduced from 85/86 to 92 with the last M119 CIS-E cars in the R129 500SL. I have not seen it on anything other than M117 560's and M119 500's. but as you mentioned, you had other models that were not available in the US that might have had CIS-E and twin pumps. I very much doubt that there were any CIS Mercedes with twin pumps and I'm going to assume that anything with a carburetor is going to only need a single pump as carbs rarely need anything more than 5-7psi of fuel pressure. My 7.7 liter Cadillac uses a mechanical pump driven off the camshaft and it feeds it plenty (PLENTY) of fuel.

Over here any of the later cars with an m103 are all twin pumped, even the 260 w201 and w124. The 420 and 500 V8s are twins as well.

The 4cyls kept a single pump, and as you say the carburettor models did to.

Your the second person to mention a euro spec (ECE) 560 running with log manifolds, UK cars never had the choice so I wonder if that was something to with emissions rules in the US? It would be interesting to have one on a dyno as in theory log manifolds should make some difference to the power output. The 420 was on log manifolds in UK but all 560 and most 500 came with the quad downpipe Tri y setup, I say most 500s as I'm sure I've seen at least 1 that wasn't. The later m119 cars only came with one option of log manifolds.

You guys in the US did get some interesting models we didn't, w124 420s being one. A few years ago I happened across a US imported w210 up for a low asking price, upon looking at the engine I was greeted with a m119. We only got the later m113 so that was quite a surprise to see, needless to say that came home with me.

 

[carat 3.6]

I don't know. And no one ever will until you spend the 5 minutes to check it out.

 

[alabbasi]

Over here any of the later cars with an m103 are all twin pumped, even the 260 w201 and w124. The 420 and 500 V8s are twins as well.

The 4cyls kept a single pump, and as you say the carburettor models did to.

Your the second person to mention a euro spec (ECE) 560 running with log manifolds, UK cars never had the choice so I wonder if that was something to with emissions rules in the US? It would be interesting to have one on a dyno as in theory log manifolds should make some difference to the power output. The 420 was on log manifolds in UK but all 560 and most 500 came with the quad downpipe Tri y setup, I say most 500s as I'm sure I've seen at least 1 that wasn't. The later m119 cars only came with one option of log manifolds.

You guys in the US did get some interesting models we didn't, w124 420s being one. A few years ago I happened across a US imported w210 up for a low asking price, upon looking at the engine I was greeted with a m119. We only got the later m113 so that was quite a surprise to see, needless to say that came home with me.

Like I said, I could be wrong about the M103 cars, I've owned a couple but it was many years ago and I didnt have them for long. I'm pretty sure that the 420SEL has a single pump and I have a parts car at the shop so I can take a look sometime and double check. It's peculiar, while I understand where exhausts might be different between US cars and Euro cars and where there might be differences between RHD and LHD cars (which explains why UK cars got fewer turbo diesels in the earlier years). I would expect fuel delivery to be the same.

Those are all CIS E cars though and I'm comfortably sure that no CIS injected Mercedes came with two pumps.

My first modern Mercedes was a 97 E420. It was a one year only model. I bought it when it was 5 years old and drove it 50,000 miles before selling it to a friend as I wanted to drive a 560SEL. I bought it back a couple of years later after I decided that I needed at least one modern reliable car with good A/C that I can count on not to nickel and dime me. The W210 is probably peak Mercedes Benz reliability and with the V8, I could still get 25 (US) mpg.

Between me and my friend, we put about 150,000 miles on it before someone ran the light and smashed into me. The car caught fire and met a sad end. I replaced it with the silver E55 in the background that sadly was also wrecked by someone jumping a red light. I still own it and plan to repair it at some point.

 

[carat 3.6]

My first modern Mercedes was a 97 E420. It was a one year only model. I bought it when it was 5 years old and drove it 50,000 miles before selling it to a friend as I wanted to drive a 560SEL. I bought it back a couple of years later after I decided that I needed at least one modern reliable car with good A/C that I can count on not to nickel and dime me. The W210 is probably peak Mercedes Benz reliability and with the V8, I could still get 25 (US) mpg.

Between me and my friend, we put about 150,000 miles on it before someone ran the light and smashed into me. The car caught fire and met a sad end. I replaced it with the silver E55 in the background that sadly was also wrecked by someone jumping a red light. I still own it and plan to repair it at some point.


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That's a sad end for the e420, hopefully you can get the E55 repaired at some point. They are a good car, it's just that over here the UK climate doesn't agree with the bodywork.

 

[Kerabo]

Hi Guys
I am still on with this job.
I have fitted a new filter at the tank and it already has a new pump.
I am happy with the accumulator as it holds a good volume of pressure a long time after being stood

I have been acquiring bits to be able to test the pressures.

So now I have a good quality gauge. I have purchased a kit of fittings that I can use to connect to various components.
As a first test can I connect direct to the line from the tank to the CIS unit?
I have looked on line and they have a feed from the pipe still connected to the CIS with a tap on it and the gauge in line with that.

Hope to test next week.

Thank you

 

[Kerabo]

I have bought a quality gauge and made some Adaptors and started checking pressures.

So new pump and filter fitted and pressure at the CIS direct is 5.8 Bar 85 Psi.
It held this until I disconnected it 15 min later and lots of fuel I guess from the accumulator ?

Pressure at the CIS head using an injector supply port is 2.1 Bar 31 Psi ? I am thinking this is too low to pass through the injectors?

It says use the port to the cold start regulator but I didn’t have a fitting to connect.

I am going to make an Adaptor and test the pressure at the small pipe that comes from what I think is the pressure adjuster.
I wondered if this was closed off the Cis head would make enough pressure to let it run and at least be sure the rest of the engine is ok.

I notice a small pipe from the head going to what I think is a pressure damper and the warm up compensator.
Can someone explain how this works please? Can I isolate it just to test?

Also a vacuum pipe from the compensator. How does this operate?

Thanks in advance