240D condition update and GP relay question - PeachParts Mercedes-Benz Forum

engatwork · #1 01-26-2002, 07:20 PM

I am running the 240D on weekends just to shake things out. And speaking of shake - should the engine shake more at idle than the 300D - it does. The motor mounts looked good so I did not replace them during the overhaul nor did I replace the engine shock - I may go back and replace the shock. It seemed quite stiff when I had it out. Otherwise the car runs out great and I actually got up to 65 mph today. I do not see where I am going to have any problem with the lack of acceleration

. This car is suited to my style of driving.
The following items are still on the "to do" list and or came up this weekend.
a) the cc does not work - I installed the actuator and did not get any response. I will start going through that later.
b) Set the start of delivery timing today and now have a good understanding of it BUT it is not as the Haynes manual says. The manual says to tie the throttle in the wide open position. I was unable to get the drops/second with it tied up like this but was successful in getting the proper drops/second with it in the normal "idle" position.
c) It is going to need a new brake caliper on the left front. This will probably be a good time to do the wheel bearings. Will probably go through the brakes over the next few weeks.

Now for the question - I opened/cleaned the glow plug relay and now I am able to get it to glow but the glow plug light does not go off even after the car is running and there is no more power to the glow plugs. I did test it and it seems that when I leave the key in the glow position the glow plugs stay energized and do not drop out. After I crank the car the power to the glow plugs does drop out. I suspect it is in one of the circuits versus in the glow plug relay. Also, once the engine is up to operating temperature the temperture gauge gets flaky (flutters around) and I think this is the same signal that tells the GP relay how long to stay on. Any thoughts/ideas will be appreciated?
thanks

psfred · #2 01-26-2002, 09:48 PM

Jim:

If the Haynes manual wiring diagram is correct, this is an electronic relay, and therefore bad. Temp sensor is an NTC thermistor in the relay.

Re-adjust the valves after about 1000 miles before getting too excited about shake -- you may have uneven compression until the rings seat properly and the valves are completely lapped in, Cassidy Machine or not (they appear to do excellent work, by the way!). You will have to load the engine quite a bit to get the rings seated -- Hans recommends several long, steep grades in top gear at low speed, with dino oil in the engine.

I suspect that if you drive much like I usually do -- that is, I'm not a stop light drag racer by any means, you never really use the available power in most cars anyway, so the 240D isn't slow. I don't notice the 220D being "slow" except when I need to pull out into traffic, and I atribute most of that to the lack of a torque convertor in the tranny, not lack of horsepower. I also never found by 1970 VW to be grossly underpowered, either. May just be what you get used to!

Check the brake hose for one-way action before you replace or rebuild the caliper -- I've had any number of them have the inner lining come loose so that the line would hold pressure. Big pain, easy fix.

Also, check that the rotors are thick enough -- far too many people cheat on brake jobs and just toss in a new set of pads. The ATE calipers will bind if the rotor is too thin -- the backing plate on the pad hits the anti-rattle spring -- tilting the pistons, already too far out of the bore, and causing them to stick. Carried on long enough, the caliper sticks, seriously overheats, and toasts all the rubber. Can be cured by a rebuild kit (new seal, dust cover, and heat shield) if the piston and bore are still clean and smooth.

Do not hone these calipers, they are chrome plated. Any rough spots on the caliper bore or piston that cannot be removed by normal cleaning means replace caliper. I've also been advised to avoid aftermarket rebuilds, too -- they seem to nearly always seize.

Peter

240 Ed · #3 01-27-2002, 05:45 AM

Jim

FWIW, I think the four cylinder will have a bit different vibration than a five cylinder.

Also, The drip method.
I didn't think this method was worth a damn. At first.
Then I found that I was off on the timing of the pump, probably due to the stretched chain.
But after finding the correct place to plug in the IP, the drip method works perfectly and easily. I used a junk yard injection pipe and cut and modified it to create the drip tube.
The one drip method is very easy to find. It is easy to rotate the pump to attain this one drip/second rate.

When I had the pump out to change the timing, I wired up the full throttle then,, as it was a Pain to do while in the car. When done, it was easy to remove the wired up throttle.

Hope this helps. I went through hell with mine figureing out the timing was off. But I had a bad valve and it was only firing on three. You talk about a rough idle???

yellowmerc · #4 01-27-2002, 08:14 PM

In my opinion, the five cylinders are MUCH smoother than the fours. You can tell just by the sound.

engatwork · #5 01-28-2002, 07:30 PM

I have been driving the 240D some more and I can't figure out what all the fuss was about it being so slow. The more I drive this car the more I like it and I believe it is going to get better fuel milage than the 300D. It drives better than some new Ford cars I have driven once you get up to speed. I found the problem with the engine temp sending unit causing the temp needle to "fluctuate". Once the engine gets up to temp the sensor becomes loose. Still havn't resolved the cc issue and I will be changing the brake lines over the next few weeks.

240 Ed · #6 01-28-2002, 11:36 PM

Eng

It sounds like you have a sweet, low mileage 240!

There is something very pure about this model, isn't there.