[noor.garcha6030]

Hey Everyone
I am from Canada, BC
Happy new year to all

Please help me

i have 1968 mercedes 250 SE 2.5 L sedan w108
Firstly, my car was running perfect and one day went to walmart and park the car, when i came back my car didn’t start. In between it started for 2-3 second and again don’t start.
Then , i came back after 3-4 hours and tried to start and it start on first crank then it runs perfect
After that, when it get hot at 175•F it stops at traffic light and 2-3 days same thing happened and when it get cool, it start and run perfect.
So, i changed the fuel pump and i bypass the pipe from thermostat.

again same problem and now it does not start on cold temperature as well and if starts i tried to push accelerate it respond very slowly and in drive barely move

today i did something wrong , i tried to start it with quick start lubricant. After long crank rear end exhaust blast.

I don’t know what happened please anybody help

thank you

 

[noor.garcha6030]

One more thing today i also change direction of distributor timing and I don’t know hot set it

 

[rumb]

Your distributor points probably need replaced and setup, then the timing set correctly. Also probably new rotor , disti cap and condensor, and spark plugs. Use only genuine bosch parts.

You need as a minimum a set of feeler blades to set point gap and a timing light.

If you are going to own a w108 the you need to buy tools as needed and learn to do the work yourself.

Plenty of youtube videos on setting point gaps and timing.

Someone here can give you the specs for each.


Also dont just throw parts at a problem until you really know whats wrong.

 

[Fonzi]

…
So, i changed the fuel pump and i bypass the pipe from thermostat.

…After long crank rear end exhaust blast.

What kind of fuel pump did you install? Short-pumps are rebuildable, and just the lift-pump to get fuel to the injection pump. They do often get gummed up after sitting, but it sounds like you may have thrown an expensive pump at a hot start problem that is probably more of an injection issue than a fuel pump issue.

It sounds like your muffler was probably already rotted if it couldn’t handle the extra fuel in it. It’s not something you want to do, but it sounds like you were going to need to replace it anyway. It just stinks when you are adding to your problems instead of reducing them.

 

[aluminum]

Most often on that Year and motor with a hot start its an Ignition problem /
I concur with " RUMB " on that > The Ignition Points ( 16 Thousands ) Coil wire / Spark Plug wires / Ballast Resistors / Distributor Cap and Rotor
Sure could be a Lot of things > but you can check the Spark just turning it over
and grounding the coil wire / Spark Plug wires to ground and see how good the spark is / all the rest you can simply inspect / Now that You moved the distributor you must re time the Motor to correct !
( Note those Rotors must fit tight not flop around )

 

[nigel slade]

I would change to in distributor electronic ignition, it makes these old cars run so much better, improve cold starting and idle etc
Fit and forget

 

[rolcanada123]

Hi What motor is in your 250SE? Is it the M130e, with 6 injection line going to the individual cylinders? Would help to know as there are a number of issues that can cause your problem. All of the people who responded are correct, you need to address, points, plugs, condenser, timing, coil, wires, before you can track down the issue. That being said, I had the same issue with 1970 250CE, most of the forums I read had a number of people with the same problem, after reading for hours I came up with a list of fixes or repairs that have so far solved my problem. I learned that the only part of the fuel system that holds pressure after you turn off the key are the lines between the injection pump and the fuel injectors. If you fuel injectors are old and weak they will leak fuel into the cylinder after you turn off the key and your fuel line will lose it's pressure (vap our lock). When you park your car, heat soak from a hot engine will accelerate this problem. Under the lines that leave the injection pump, there is a fitting that can be unscrewed and when removed has a white plastic seal that will get hard with time and will also allow the lines to leak fuel back into the pump and lose your line pressure. So if you don't know how old your fuel injectors are, they should be replaced, $150.00 ea ball park an injection pump rebuild kit is available on eBay with the seals you need. $100.00 I also did the following, Replaced the old fuel pump with a Pierburg pump of the same specs. 17-19 lbs pressure with a liter of fuel every 15 sec. volume. Replaced a missing radiator shroud (very important) Installed a 5 minute relay, hard wired to the battery that operates the aux fan I had from a removed AC unit. Just before you turn off the car to go shopping, hit the switch and the aux fan will run for 5 minutes after you turn off the car, reducing heat soak. I store my car for the winter but it is my daily driver during the summer and I have had zero issues for the past two summers. Hope this helps Cheers Rollie