1981 300 Sd Turbo Diesel Newbie Help

[kmichael30]

Hello group, i'm the proud owner of a 1981 300SD that was given to me as a gift. Great car, but it has not been started in 2 years. I changed the oil and put 2 new filters drained the old gas out and put new gas in diesel of course tried to start it and it sound like it wanted to crank but it would not start. what should i do next please go easy on me guys i love this car, but i don't know anything about them. I have a can of the diesel purge but i think that the car has to be running to use it any ideas on what to do to get this baby to crank

[Brian Carlton]

When you changed the fuel filters, did you run the hand primer pump about 100 strokes to force fuel through the system?

This pump is on the driver's side of the engine, down low on the block. You can see the fuel hoses going into the lift pump right near this primer pump. It's usually a clear plastic device with a plastic plunger handle. Sometimes, when very old, it leaks like hell and needs to be replaced with the newer design.

[whunter]

Originally Posted by kmichael30

Hello group, I'm the proud owner of a 1981 300SD that was given to me as a gift. Great car, but it has not been started in 2 years. I changed the oil and put 2 new filters drained the old gas out and put new gas in diesel of course tried to start it and it sound like it wanted to crank but it would not start. what should i do next please go easy on me guys i love this car, but i don't know anything about them. I have a can of the diesel purge but i think that the car has to be running to use it any ideas on what to do to get this baby to crank

Did you fill the new filter with diesel, before you installed it?
Does the diesel engine crank faster than a gasoline engine?
Do the interior lights get dim during the glow plug cycle?
Do you have a fifty amp or heavier battery charger?

Note:
You may use diesel purge to fill the fuel filters.

[kmichael30]

no guys i hav'nt done none of those things i will give it a try and let u know what happens thanks

[RockinWagin]

Originally Posted by kmichael30

no guys i hav'nt done none of those things i will give it a try and let u know what happens thanks

Where in Texas are u, anyway?

[Brian Carlton]

Originally Posted by kmichael30

no guys i hav'nt done none of those things i will give it a try and let u know what happens thanks

You definitely must fill the secondary filter with fuel.

Then you must pump the primer pump until you hear all the air escape out of the top of the secondary filter.

Then, start the engine.

[P.E.Haiges]

kmicheal30,

Your troubles began when you "fixed something that wasn't broken". Learn from this experience.

You should have just tried to start it and not F***** with it when you didn't know what you were doing. It probably would have started unless the fuel was contaminated with fungus and couldn't get thru the filters, but this is rare. Diesel fuel is not like gasoline, it doesn't deteriorate. I used Diesel fuel that was over 10 years old with no noticeable difference.

What did you do with the fuel you took out? It you still have it, put it back in the tank, there is nothing wrong it unless it has fungus in it. Then it and the fuel system must be treated with a funguscide such as Biocor.

BTW, you are actually trying to start with the old fuel because it takes a while after the engine is running for the new fuel to get to the engine.

P E H

Do any of the dash lights come on when you go to start it (BTW I have a 81 300SD too!)?
WHen you turn the key to the start position does the lights (dome light) get dimmer?
Charge the battery and try again
Email me if you have any car specific questions...I have been through most of them..

[kmichael30]

Thanks for all of your advice i will give it all a try i will keep u guys posted btw i drained the old fuel out and put new fuel in

[kmichael30]

while trying to start the car 1980 300sd the dome light did get dimer and it sounded like it wanted to crank but it still would not start wile it was trying to crank i steped on the gas pedel a few times good or bad idea? i used the primer pump and pumped the hell out of it untill i thought all of the air was out of the system then i stopped when the car still would'nt start i went back to the primer pump again and started to pump and once again i herd air comming out of it should i just keep pumping it untill i don't here anymore air will i flood the engine this way hit me up with some more ideas

[jake1222]

When you use the prime pump you have to loosen the large bolt on the secondary filter first, after you do that then you pump the primer pump until there is no more air but ALL fuel coming out of it. You will NOT flood the engine, the more fuel the better (Unless it is gas in there and not diesel fuel,SVO/WVO ect...). After you have done this then test your glow plugs with a voltmeter to see if they're getting 12 volts or so. Then try starting it if all of this checks out.

[83mercedes]

I'm not sure if you have the same fuel system as on the 300cd (my car), but I believe it is close enough.

Here's the deal with the fuel system:
1. Like Jake said, either fill the screw-on filter with fuel or unscrew it a little bit and pump the fuel primer pump until fuel flows out of the top without any air bubbles in it, then retighten. Pump again until you hear a high pitched squeak kind of noise coming from the injection pump area. You didn't mention you had done this in the last post.
2. Make sure the primer pump is not leaking fuel everywhere (if it is just buy a new bosch upgrade pump, they're $20, easy to install, and don't have to be unscewed like those PITA white plastic ones), you didn't mention this either.
3. Pump the primer pump until you hear the squeaking noise. Beyond this is overkill, but not harmful. You will be able to see fuel flowing through the clear plastic pre-filter if there are air bubbles in it (which there usually are, simply the nature of the design, they stay right at the top, but not a problem) if your primer pump is working.
4. If all these measures fail and your glow plugs are drawing a charge (it should be starting after a bunch of cranking in normal weather w/ bad glow plugs anyways, unless you have very poor compression) then check your in-tank fuel screen. This is located at the bottom of your fuel tank and you will have to drain all your fuel out and remove the line. It unscrews with a biga** socket you have to get. Should be able to find info on this at www.**************.com under maintenance alerts or if you search the forum. Sometimes crap in your tank plugs this fuel screen up and makes starting hard and performance poor. I'm not sure it would prevent your car from starting entirely, but it could contribute and succeed in conjuction with other problems.

Hope any or all of this helps.

[kmichael30]

thankonce again guys for all of this info may god bless you all

[t walgamuth]

all of the above advice (that i read) is good. a quick fix is to spray wd40 into the intake with the air filter off. it will run on it long enough to prime the pump. the glow plugs do have to work though. don't feel bad. i am sure that all advice is well intended. it is human nature to think mechanical problems are caused by something complicated. good luck.

[MS Fowler]

One of the beauties of these older, simpler, mechanical diesels is how simple the diagnostics can be. Especially for a no-start condition.
In a gasser, the fault can be either the fuel system, or the ignition system, ( assuming no mechanical problems). Either system can be controlled by a computer, many sensors and connections--a fault anywhere in the system can cause it not to run.
In our older diesels, its the fuel system, period. If the engine cranks at a high enough speed, the glow plugs light and fuel is present it will start. ( Glow plugs are not always required--I have started using a hair dryer blowing hot air into the air cleaner inlet). Don't start out thinking the injection pump is faulty, or has lost its timing. Do the simple stuff first. Make sure fuel flows, the filters are not clogged and the battery is fully charged. You can always remove a couple of injector lines at the injector end ( the metal ones) and see if they spritz a LITTLE fuel as the engine is cranked.
And keep us posted on your efforts to get it started!