1964 300SE Coupe in storage

[RoyB]

Greetings all.
I have a 1963 230SL and was asked by a friend to visit one of his friends who has a 1964 300SE Coupe that has been sitting in the garage for at least 12 years.  The body is clean and straight, with no rust.  As expected, the tires are flat, and there is dust on everything.  The owner has asked is I would be interested in trying to get the car running again.  He wants to ride in in one more time, so that gives you an idea of his mental and physical state of health.  My 230SL has not been the first Mercedes I have owned, nor will it be the last.  With that said, I have plenty of manuals and repair books, but it seems that the W112 - 300 Engine series are very exclusive, and seemingly harder to find parts for. 
My plan - if I move forward is this.
1.  Put the car on Jack stands
2.  Remove the spark plugs and squirt oil into the cylinders
3.  Remove the valve cover and inspect the timing chain and gears, then pour some oil down the passages.
3.  Using a socket (22 or 24mm if I remember correctly) turn the engine over to see if it is free.
4.  If the engine turns over manually using the socket, focus on the fuel system.
5.  Remove the old fuel by draining the tank.
6.  Pour in a a little fuel to flush any other contaminants from the tank, while cleaning the filter.
7.  Put in a few gallons of clean, ethanol free, premium fuel.
8. Install battery and turn on the key to verify the fuel pump works.
9.  If the fuel pump works, put in new spark plugs, gap the dual point system, and drain the oil.
10.  Install new fuel and oil filters and change the oil.
11.  Try to start the engine

If I accept the request to get this car running, what I am getting myself into?
The car in near my home in Inman, SC.  Thanks

[wwheeler]

I think I would also focus on the brakes. Won't be a good ride if you can't stop. Is this 4 wheel disc?  At least change the fluid and hoses.

What about auto trans, power steering, engine coolant and more importantly the air bags for the suspension? Not sure how the bags fair being collapsed for 12 years. Not sure what vintage IP that is. If there is a dipstick in the back, drain the oil and put new in.

[Vander]

I have a 1964 300SE Lang , and I think your list is a great start! Once you get it running, hopefully the air suspension raises and stays up. Another thing, does he want to just go around the block, or does the car need to drive at freeway speeds across town? More work is involved for that.

[RoyB]

Thanks wwheeler and Vander.  I am going to meet with the owner tomorrow to discuss his expectations.
If I get involved, I suspect I will try to get the engine running.
If the engine starts, then I will focus on the driveline, suspension, brakes and tires.

[Bonnyboy]

Be very careful - that is the kind of car that will steal your heart -  the last time I got a vehicle running for someone I fell in love with it and ended up buying the darn thing.   

Good luck.

[Benz Dr.]

I've worked on several of these cars and their later cousins like 6.3 and 600. Air suspension is a whole different animal and 300SE is different again from all others. These valves only have one level instead of the two found on later cars so they're hard to find and basically made of unobtainium.

The 300SE engine has very little in common with a 230SL except that it was built by MB. Front brakes are similar but rear discs are totally different. Rear axle is LDS with a sway bar. If the car has A/C it will probably have an oil pressure operated fan with a thermostat and it will leak oil everywhere. Engine uses its own specific IP and injectors ( I have quite a few NOS injectors ) which are NLA along with a number of parts only used on this engine. Block  and head are aluminum alloy but the 7 main bearing caps are forged steel which makes align boring very difficult.
Ignition caps are available but very expensive. I use the same dual point unit on my car but I'm using a cap from a BMW - about a tenth the cost.

Lovely cars but expensive parts and not everyone can work on them. Not impossible to work on but they are a challenge even for the experienced.

[rockingchairmotors]

Old Mercedes mechanic told me to use ATF to lube things.  Cylinder walls, fuel system, etc.  Also make sure the injection pump has oil in it. 

I was told to crank the engine with oil/atf in the cylinders and the plugs out.  Might spray all over but less stress on the engine and no hydro lock up.


Good luck.  Let us know how it goes. 

[m300cab]

if necessary you can swap the distributor for a 123 distributor
if it was running when it was parked 12 years ago, you will be surprised how
easy it will be for it to come back to life
the best is when you are driving over 100mph, it forgets it's a coupe and transforms into
a 300SE Roadster/Gullwing-Great Fun

[m300cab]

replace brake flex hoses, and master cylinder first
see if there a receipts for calipers if not you can take those off and rebuild them
then replace.

[scoot]

3.  Using a socket (22 or 24mm if I remember correctly) turn the engine over to see if it is free.

The M189 engine is different.  The crankshaft pully has holes in it such that you can stick in two philips screwdrivers and turn it with your hands on the handles of the screwdrivers.  Much easier from the bottom of the car.

[RoyB]

Scoot
The bolt on the counter balancer requires the same tool as a Honda Interstate motorcycle for dissembling the clutch.  I ordered one of those tools, and will try that along with the screw driver trick.  I have had penetrating oil in the cylinders for a few weeks now, so hopefully the engine will turn over manually.  If so, I will take off the valve cover and pour oil down the passages, then drain the old oil and refill with fresh oil and a new filter prior to checking the fuel pump.  Hopefully after all that, I can try to start the engine. 

[RoyB]

Despite all efforts, the pistons and rings are still stuck to the cylinder walls.  I have been spraying PB Blaster (rust dissolving spray) into the cylinders.  The Honda Interstate clutch tool fits onto the splined nut of the counter balancer, but the engine will not budge.  I am going to shoot some ATF into the cylinders and give it one more try.

[Jonny B]

Did you try to nudge it just a little in the opposite direction? Some times that can help to free up a rusty bolt, perhaps the same principle could free it up just enough to get the proper turning direction into play.

[UJJ]

You also can try to put the car in gear and rock it forward and backward.
Maybe this gets it loose.
Good luck, Urban

[RoyB]

The tribulations on this car continue.  Per the discussions above, the engine is still frozen.
After a discussion with the owner, he has asked that I pull the cylinder head to see if how badly the pistons are rusted into the liners.  My manuals imply that the timing chain needs to be split, or cut to remove the cylinder head.  Is it possible to lower the chain far enough to drop it off the gear on the crankshaft so I can rotate it to find the split link?  Does anyone know where engine parts, gaskets, timing chains, etc can be sourced?  I am not finding many parts for the 300SE in my search.
As always, thanks for your help.

On another topic, the transmission is back in the 230SL after installing new bearings.  Thanks to Pat for loaning me the tools.

[ja17]

You can remove the cam gear with chain. Remove any chain rails in the way and the chain can be lowered un-broken. Otherwise, split the chain and add an additional master link later or replace the entire chain. Removal of the intake manifold is much more tedious than that of the pagoda. Parts are out there but much more expensive than a pagoda. A new timing chain is not much money compared to everything else.