460 280ge Turning over the engine
I have recently acquired a 280ge which has been sat for around 17 years. Before changing fluids I am doing a compression test.
I removed the spark plugs and disconnected the HT leads at the distributor, as well as removing the fuel pump relay from the fuse box under steering wheel and connected the battery from my other car. Turned ignition on and tried to crank and all I got was starter motor wheeze.
I didn't get a multimeter on the starter motor or hit it with a hammer, first I wanted to check I could turn the engine over by hand.
I have downloaded a pdf of the workshop manual but it is a scan and not easily searched
The Problem
I've had a feel and I don't think there's an exposed crankshaft bolt on the crankshaft pulley. It doesn't seem very Mercedes but it does appear to me that I'm going to have to remove the crankshaft pulley to get to the bolt. To remove this pulley, since I can't see a tensioner I must have to remove the power steering and alternator pulleys first? (Non-AC model)
If anyone could give some advice on getting to the crankshaft pulley that would be great!
You seem to be doing all the right things, but surely hitting the starter with a hammer is the first course of action, then all the rest can be avoided (if it can free up the engager). You will have to sort that sometime.
I can tell you the firing order on the 280 is 1-5-3-6-2-4
0.8mm on the spark plug gap.
The Operating manual has 1 picture of the pulley, and no nut. There is one on the power steering pump though if your belts are still on.
I made a mistake: not unheard of. I called a neighbour over to show him my horn as I think it sounds awesome. While he was there I showed him my engine not turning over, he looked at me as if I was crazy. Of course I couldn't see it with the bonnet across windshield but the engine was in fact turning over smooth as you like, it's just the starter motor sounds unhealthy - not going to look into that for now I don't think.
FWIW I couldn't get the engine to turn by putting a spanner on the power steering pump (or altenator for that matter) the belt just slipped on the given ancillary pulley.
So I've pressed on and run cold dry compression test as follows:
| 1 | 2 | 3 | 4 | 5 | 6 |
| 7.5 | 9 | 9 | 7.5 | 9 | 9 |
The owners' manual shows that the minimum compression ratio with a warm engine should be 7.5 bar* so as far as above minimum tolerance goes I am happy with these figures. Okay 1 and 4 are 12% under the mean but I think a warm engine could see them brought back up. Interesting that it was 1 and 4 though which are in symmetrical positions on their respective exahaust manifolds, I wonder if the design gives slightly higher egts on those 2 cylinders and causes piston rings to go sooner. Anyway I was happy enough with these so didn't bother with a wet test. If I am loosing coolant when I manage to start it I will revisit my head gasket query with a sniff test on the coolant system.
* Note that this is for a 280ge, if anyone coming back to read this from the future with a 230ge your engine runs at a slightly higher compression and so the values should be 8.5 bar minimum
lol. thats funny.
but good news so far. I don't think that 'lower' compression will matter too much for petrol engine, though it does indicate wear somewhere. But that engine has sat for years, so you should repeat once running properly.
Now you know its not seized.
Back to the firing sequence. I don't see how the distributor can be connected in anything other than the specified sequence.
I agree, very good news
as for distributor, I just had a quick go after work and I think the previous owner had the 1st lead in the right place then messed up the firing order a little. I verified I was getting a spark so on to fuel
I wasn't getting any so I did a quick paper clip modification where the fuel pump relay had been (and filled the tank with some petrol which no doubt helped) and all of a sudden I was getting fuel - lots of it. Unfortunately my high pressure fuel line is gushing a bit right next to the battery so that's not ideal. The engine however runs and sounds very healthy - all 6 cylinders too :)
Just to find a new fuel line or get one made so I can start to look at this transmission (I tried improving previous owner's electrical tape bodge on fuel line with self amalgamting tape but it wasn't having it. I'm letting it dry thoroughly before trying self amalgmating tape again - I think the pressure is possibly too high for it though)
At this point I should concede that this thread is now royally off topic - someone please advise me if I should keep going or move this to a more appropriate section
RESULT.
Keep it going. people always want to see the journey. High pressure fuel lines are cheap to replace (braided rubber ones) and one thing that duct tape (or amalgating tape!) wont solve for any length of time.
Presumably there is more serious issues with the tranny, if engine running OK. But they are normally bullet proof. See how you get on, but a replacement might be the way to go if you hit trouble.
I am having minor issues with my KeJetronic fuel injection - all to do with ensuring you have fuel pressue (control and delivery) and no vacuum leaks anywhere. Its running great at the moment though. Hopefully yours is good enough but after all that time stood the things that go are: fuel pump (easy to tell), fuel acumulator (mine was gone and caused poor start), [both up on the ladder chassis behind the nearside rear wheel, UK] and Idle Control Valve (mine is OK, possibly). Also the fuel pressure regulator on the side of the meter head (not checked).
Obviously change the fuel filter.
Where in the world are you?
280 Starters are prone to oil ingress from leaks and are getting hard to find, overhaul of your unit is probably the best solution
M110's also like to stick Exhaust Valves when stood a while and I guess 17 years will pass that level easily ;0)
May well come back ok when running and warm
Good luck!
I think the clue is in:
Hi I am in Chatham, Kent and thanks on the info on starter
I was able to short the relay and get the fuel pump running for a while but my delivery line to the fuel distributor was leaking badly and my high pressure petrol resistant self amalgamating tape just didn't work as the whole hose was gone. Today I got a shop to crimp me up a new fuel hose.
Once the fuel hose was connected back up again I now no longer get fuel. I can feel the relay switching in my hand with ignition on but the fuel pump just isn't pumping. I will have to locate the fuel pump to see what is happening here
(And Mark I saw Gav's message and went ahead and added my location to my profile but was going to reply once I'd done some more investigation with my new fuel hose - at the time they commented, I did not have a location in my profile)
I think m102 and m103 engines got KE Jetronic, but the older m110 unit was a more basic K-jet
I think m102 and m103 engines got KE Jetronic, but the older m110 unit was a more basic K-jet
Yes mine has K jet - I think JDring was referring to his which is a 230ge but I've no idea what that runs.
***
To add some more info to the above post as I felt I didn't include enough info
My fuel pump relay I have the following wires
Red - permament live (not ignition live)
Green - ignition on signal (switches relay when ignition turned on)
Brown - chassis ground (12V to red, correctly grounded then)
Red + Black (RB) - fuel pump power feed (when switch closed takes power from Red)
I believe my relay to be not so good as although I did feel it clicking in my hand with wiring set up as in the Operating Instructions booklet, I never recieved 12V red+black - brown. So I shorted it by taping red and RB together. This worked the other day, I could hear fuel pump, fuel was spurting out.
Yesterday, no fuel out of my newly repaired hugely expensive £18 line. So as I said I'm going to go digging around to find this fuel pump which I've read somewhere is not super obvious to access. I hope to make time to do that this weekend. I'll try and put 12V across it and see if it does anything before disconnecting and binning if not. Replacements seem to be £30 on ebay, hopefully they're not too bad. I'll also see if I can't find a new relay while I'm at it.
It also looks like there's two fuel filters? The metal lines from filter look pretty awful so I'm actually going to hold off changing the fuel filter for the time being unless they become a big issue with fuel pressure, as while I debug the other stuff I don't want to create anymore fuel leaks. Once I've figured the gearbox and transfer case out, I'll come back and change the fuel lines on the chassis.
You are looking at the Fuel Filter and the Fuel Accumulator (keep fuel line pressurised). On the ladder chassis behind the nearside rear wheel (UK).
I think your fuel pump relay sounds bad. I had to replace mine (well I had it replaced, not me). Don't wire the fuel pump direct (some muppet had done that on my 230). Because (a) the pump runs nonstop and (b) its dangerous in an accident.
The Accumulator only needs replacing if you have a bad start condition (cold or hot). The Fuel filter is a given, especially after a long lay up (which also kills the accumulator diaphram)
See the attachment here. Its a good overview of all the fueling components.
HAHA Mark .. not that slow.. yet!
FPR do go bad... two types and you can hard wire 2 pins for test purposes think 13/87 but quick google will tell you
Should also have early type overload protection relay that Fuel circuit runs thru so check fuse in top of that and relay also
Make sure all fuses are good and then check contacts and then check again!
Make sure you squeeze each one in gently to make sure it grips the fuse properly
You are looking at the Fuel Filter and the Fuel Accumulator (keep fuel line pressurised). On the ladder chassis behind the nearside rear wheel (UK).
I think your fuel pump relay sounds bad. I had to replace mine (well I had it replaced, not me). Don't wire the fuel pump direct (some muppet had done that on my 230). Because (a) the pump runs nonstop and (b) its dangerous in an accident.
The Accumulator only needs replacing if you have a bad start condition (cold or hot). The Fuel filter is a given, especially after a long lay up (which also kills the accumulator diaphram)
See the attachment here. Its a good overview of all the fueling components.
Thanks that is a really useful document I've just had a quick read but will have a better read later. I applied my battery directly to the fuel pump and got nothing so I think I burnt it out bypassing the relay (I think it would have gone soon anyway). The new ebay pump arrived today so hopefully I can fit that after work. If fuel line to accumulator needs to stay pressurized, once replacing the fuel pump I will apply battery to it directly again to prime the accumulator which will no doubt lose a bit of fuel in the operation, I'll also look to stem the lines as I do this.
I have a new relay on order, the original one has been deprecated in favour of 0332019151 for anyone that might find this useful.
The fuel filter will be done but not now, as I now that if I disturb those lines I am going to have a big problem. I'm going to have to make all new fuel lines by the looks of things.
When I acccessed the fuel pump behind that stupid shield (snapping all the crusty bolts) it was packed with some kind of insulation. Too late now, but did I need to be concerned about asbestos?
FPR do go bad... two types and you can hard wire 2 pins for test purposes think 13/87 but quick google will tell you
Should also have early type overload protection relay that Fuel circuit runs thru so check fuse in top of that and relay also
Make sure all fuses are good and then check contacts and then check again!
Make sure you squeeze each one in gently to make sure it grips the fuse properly
Thanks yes it is 30 and 87 -> I think these are the standard input and switched output for relays as I've just been chasing a non start issue with my saab and that was also 30 for permanent live and 87 for fuel pump relay feed. To help anyone searching this in future as I only gave colours before 30 = red, 87 = red+black. I used paper clips to quickly test this the other day but as these circuits are typically fused to 30A+ as here it's not great practice. For testing purposes best to make a fly lead out of some house twin and earth wiring so I just pulled a live wire from some 2.5mm and added spade connectors on the end to bypass relay.
In my cases my relay was not good last week which is why I bypassed it, but then my fuel pump gave up. New fuel pump today, continue to bypass relay until new one arrives - I'm hoping it starts again, just without leaks this time.
***
To get it through an MOT it will need the door sills welding, and I've found someone that will fix all the body work for me in January when he opens his new shop. Mine is a swb, I can see that only lwb replacement sills can be bought on ebay, do they cut and stick nicely to become swb sills?
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Hi and thanks for the reply. I will hit the starter later and see what happens, I just wanted to sanity check it wasn't pushing against a seized engine - although I'm doubtful the starter motor would be strong enough to do any damage to the timing chain etc I didn't want to find out the hard way if indeed my engine were seized.
Thanks for the timing order, I did in fact see this on the valve cover which I thought was a nice touch -> when I traced the HT leads back to the distributor I noted that the leads were not in any (anti)/clockwise firing order on the distributor. This I did find a little surprising given that when i took the distributor cap off it looks like a device that rotates the point of contact to initiate firing -> it seems wrong that this distributor wouldn't have been set up in a 1-5-3-6-2-4 sequence. A trivial point for now though while I work on cranking but it's something I might need to check at some point.
My main question to your response would be; is turning the power steering pump going to give enough friction on the belt to turn the engine also? Or is the belt likely to slip on crankshaft? It shouldn't cause any harm to try either way
I will also check spark gapping before reinserting so thanks for the gaps too. I have a funny feeling that I will be discovering that the head gasket has gone -> there is a large oil stain on the front left (if looking from radiatior, also RHD side) at the top of the block, and when I went to remove the spark plugs I noticed that the central two cam cover bolts were finger tight so someone has clearly been here before me. I was told by the previous owner that it was parked up because of either a transmisison problem or transfer box issue.