79 300CD wont start/running out of check list

[chasinthesun]

The following has been completed

1 changed glow plugs -needed
2 new starter - needed
3 set valve adjustment- needed
4 using clean fuel from can /purge setup
5 all pulleys are checked/ no siezed bearings
6 hot battery
7 priming fuel

ok ,heres the things I noticed while turning it over ,it still is turning slower than my other car,could this be a bad carbon buildup ?When putting the glow plugs in I noticed a carbon type residue on the end of the glowplug ,and when I rescrewed the new ones in it had the same crap on them when I checked them one last time. Is the prechamber badly carboned up?Can I take the exhaust and intake manifold off and see this ? Does this require me to do the upper end? This car will not start with the help of ether ,only used small amounts of it and could not even get it to cough.The way the valves were way off this car had not been under the best maintinence schedule.

[chasinthesun]

the injector was checked by pulling the lines off and the drip method ,a ok

[Old Geek]

Sounds like you have some carbon build-up; but that is not usually an issue for start up problems (that can be addressed later with an Italian Tune up).

Did you check the condition of all the Glow Plugs - do they all have carbon?
Are you sure the glow plugs are getting hot? Is the Glow plug dash light coming on when you turn on the key ?

If the engine is turning over slowly, and even though you say the battery is 'hot' - the battery may not be putting out enough Amps to properly turn over the engine fast enough to start. Do you know when was the last time the car was running?

Try checking the cranking amps of your battery - it may be time to replace the battery Also check the grounding leads on the car body (remove any accumulated rust).

[bergmjh]

Be sure you have voltage to the glow plugs. If you overtighten electrical connection on the new ones you can ruin them. Be sure each glow plug draws current. Take a jumper cable from the posative side of the battery and see if each plug will draw current. You will see sparks when touching the electrical part of the glow plug. Good luck. John

[t walgamuth]

agree and emphasize to check grounds
tom w

[450slcguy]

glow plug timer relay...?

[Brian Carlton]

Originally Posted by chasinthesun

This car will not start with the help of ether ,only used small amounts of it and could not even get it to cough.The way the valves were way off this car had not been under the best maintinence schedule.

This tells me you have compression problems and that all of your efforts will be for naught. Either the valves are burned (likely) or the rings are shot (less likely). Time for a compression test to see where you stand. Don't throw any more good money at it.

You don't need functioning glow plugs and you don't need bother "checking grounds" to start it on ether.

[chasinthesun]

Carlton, explain please,do I need the top end done ,new valves,what do you recommend .The battery was hot ,I reinstalled the large battery in my wagon after tring to start the coupe and it started up with no problem,there is definate carbon build up ,can I take the intake and exhaust header off ,scrape the carbon,if abundant amounts ,vacuum out as much as i can ,reinstall exhaust and intake ,then try to start ,the slow turning motor is at less than half of what my wagons turning rate is.This car was bought for $250 ,so Im probably in for a few more surprises but dont wont to give up on the old car just yet.

[Richard Wooldridge]

Hi there,
Your starter is a 4-pole motor. it's possible that one brush isn't doing it's job and is causing the starter motor to only have half the power... this could be causing your slow turnover. The only problem is you will have to remove the starter to check it. And, if you have to remove it, you might as well replace the brushes in it, or install a rebuilt unit.
Also, you might try removing all the glow plugs and turn it over on the starter to see how fast it turns. If it still turns slow, it's most likely the starter. While the glow plugs are out, do a compression check. You should get at least 300lbs of compression on all cylinders. If you do, remove one injector at a time and let it spray into a can. See if it REALLY sprays any fuel.. If it does it should start. Use a hair dryer, blow hot air into the intake. If it has fuel it should start with the hot air in the intake manifold, even with no glow plugs operational - this is a trick I have used to start an old tractor. The particular tractor I use this on, an old Ford diesel tractor, only has two glow plugs, both in the intake manifold to preheat the air, and it doesn't like to start on cold days unless it gets a little help from the hair dryer.

[atikovi]

There is a REASON you got the car for just $250. Start with the basic compression check before spending any more time or money on it. And don't forget, even if you get the engine running, the transmission may be shot.

[Brian Carlton]

Originally Posted by chasinthesun

Carlton, explain please,do I need the top end done ,new valves,what do you recommend .

I recommend that you perform, or have a qualified mechanic perform a compression test. If the numbers turn out low, he should add some oil to the cylinders to make determination if the problem is rings or valves.

If the numbers turn out OK, then you have something to work with.........the thoughts of a slow turning starter might be accurate.

[boneheaddoctor]

Ether can be devistating to a diesel engine, even though some people have gotten away with using it. I myself will NOT try it with a diesel. Always better to be safe than sorry.

Check grounds well..also I am asking this becasue I did not notice if it was mentioned...were you using the same battery on both cars you compared to each other as far as cranking speed?

[RAYMOND485]

1984 300d Turbo
Remove Glow Plugs And Use A Reamer To Remove Carbon, Also Install A Rebuilt Starter It Will Turn Over Faster And A Good Battery.

[chasinthesun]

Has anyone seen carbon restrict the air and fuel mixture so much from keeping a car from starting, I remember a van I had this AND was the problem for my hard starts and rough idle,the carbon was so bad the mechanic was chiseling globs of carbon off the internal combustion area.

[atikovi]

Common problem on VW TDI's. Air flow is greatly restricted due to the crud building up in the intake plenum and manifested by power being way down. Should not have an effect on starting unless almost totally obstructed.