250 engine mystery

[oldmercfan]

Hi experts, can you help with an 250 engine query. A friend of a friend has a 250 they are thinking about parting with. They took possession of it about six months as a swap for another vehicle, and did so without the engine even running. It fires up if you pour some fuel down the carbs, but splutters out rapidly. A fuel blockage or maybe a pump issue. Anyway, the I took a look under the hood yesterday and I will be a monkey's uncle if it is not something bigger than the 250 engine in my car. Excuse my complete ignorance here, but it has one of those skinny vertical radiators jammed in to the right hand side of normal radiator. Is that an oil cooler, and what does that tell me about the engine that is most likely in this car? Your wise opinions, as always, are highly appreciated.

[Giles]

The issue with the fuel I would tend to think that this is either a faulty pump or a very blocked fuel filter.

I don't know much about 250's but as far as I know all W114's have the oil cooler.

Giles

[oldmercfan]

Thanks, Giles. My 250 (a 1970 model) doesn't have one, so I guess some of the earlier ones didn't have the oil cooler. Tell me, where do I find the engine number? Is it on the right hand side of the engine (as you stand in front of the vehicle?). I recall now seeing a number there starting with 130, so I am guessing that tells me it is an M130.

[New123]

It would help to know what model you have. Is it a 250SL, 250SE, 250C, 250CE, 250S, etc?

You are correct though, the engine number is on the passengers side (on a RHD car) towards the back near the top of the block, just below the head. If it starts with "130", then you have a 2.8 litre DOHC engine. Your car must be a 280...something.

Once again, not too much more to add until a determination is made on the model of the car.

[oldmercfan]

Thanks, Toby. The badge on the back says plain old 250, which is what vexed me. Its a big SOHC engine, and from what you say about the location of the engine number, I did indeed find it. It starts with 130, so its the SOHC 130 (not the M110, which is DOHC). Intringuingly, Wikipedia says there about 22,000 250s built with the 2.8 litre M130 engine, but they were still designated as 250. Maybe its one of these cars.

[New123]

Ah yes. I should have checked a few things before posting. Yep, that would be a W114.011 chassis. A 2.8 badged simply as a 250.

[TheMadRacoon]

Perhaps the oil cooler next to the coolant radiator is for auto transmission models only - ie auto trans fluid radiator.

[Giles]

Perhaps the oil cooler next to the coolant radiator is for auto transmission models only - ie auto trans fluid radiator.

Afraid not, just pulled a manual radiator the other week from a W114 280CE and it had an oil cooler. No auto trans connectors though.

I think we need a VIN number.

Giles

[Giles]

Pick a number.

image.jpg

Giles

[New123]

The oil cooler is an engine oil cooler which is connected at the oil filter housing. Here's mine waiting to go back in the 250CE...(blue arrows show the upper and lower oil lines to/from the cooler)

[ansteadeh]

You certainly would have the M130 series of single OHC six cylinder. Like the picture above. The full engine number and chassis number will be a better giude for us all. Assuming that the engine is original it likely has the twin dual throat Zenith 4INAT carbs.

The problem you are describing sounds like a fuel supply issue. Do you have fresh fuel in the tank? If it is firing, I wouldnt touch the ignition system (yet). Disconnect the fuel line to the carbs and crank the motor and see if you can empty some fuel into a container. If not, then you have a buggered pump, blocked filter, or blocked line. Check that first.

if you get a good supply of fuel and the motor starts but not run, then the carbs may need some attention. These are very difficult carby to set up correctly, but first get back to us with the engine/chassis and how you go with the fuel.

You could also look for a post from Mercmad on this list. He has previously posted some very good step-by-step guides for geting a motor running from a similar state you are describing.

Good luck.

[interloper]

I'm new here but I have a '73 250 with the same 2.8L SOHC engine, so there must be a few around....

does have the 2x twin throat Zeniths also