Diesel Newbie - PeachParts Mercedes-Benz Forum

BigMikeT57 · #1 10-06-2003, 04:56 PM

Just acquired a new project. '83 300D 195k. Was donated to a charity and resold. Knowing it would need some work, I bought it for less than $800.
If I can make it road worthy, will be a Biodiesel experiment.

Have only driven it about 3 miles to get it home.
Initial impressions are:
Engine pretty clean ( no leaks )
Body has very little rust, but pushed in quarterpanel.
(pushed out most with my palm from inside trunk.)
Tie rods bent by tow hooks.
One of the rear brakes is probably frozen.
Rough idle when cold, smooths out with 30-60 sec. ( Glow Plugs? )
Engine seems strong, but seems to top out around 45mph.
Tranny shifts hard and irratically.
Door locks don't work.
Based on reading here, I think the speed, shifting and locks may all be related to vacuum.

Have been doing searches for individual problems, but in the big picture, thought I should post.
Any suggestions on what to do first?

I would like to work on the main drivablility issues first (and cheaply) then decide if it is worth investing more money and time into or part it out and keep looking.
Thanks for any and all suggestions,
Mike

psfred · #2 10-06-2003, 07:57 PM

Mike:

Tie rods and brakes before driving, please!

Rear calipers are probably siezed, get a kit for each and replace the seals. Not very hard to do. Most likely the rotors are shot, so expect rotors, pads, and caliper kits all round (not that expensive). Bent tie rods have to be fixed to make it driveable.

While you are doing that, get a MitiVac hand pump and figure out why the door locks don't work. You have a least one diaphram gone, or the switch on the driver's door is shot. You will have shifting funnies until you get them fixed from low vac.

Replace all the rubber connectors on vac lines in the engine complartement, they are all dead and leaking. This alone may fix the door locks. Ditto for the climate contorl problems you haven't found yet.

Low top speed is either leaking fuel lines on the suction side of the feed pump or plugged filters. Replace both filters, and if the clear one is black, get some biocide at the marine supply and treat the tank, you have algae. If the priming pump is the old read handled one, get a new sealed type, the old one will leak if you use it.

That should get you running!

Peter

BigMikeT57 · #3 10-06-2003, 08:54 PM

Thanks Peter,

I definately agree with you on the safety issues b4 driving statement.
Since this car is not needed as a driver right now, I was thinking in terms of testing the major components (engine/trans) b4 expending energy and time on the rest. If the major components are a wash, I'll bale and part it out.
What should I do first? Compression test? Diesel purge?

Thanks again,
Mike

dabenz · #4 10-07-2003, 07:17 PM

Hi Mike. Betcha that Camry's gone in a year. You're gonna get addicted. And listen to Peter: brakes and tie rods. I have relatives in Jersey, you know.

You can use the MityVac to flush the brake lines. Your car is probaly typical, meaning the annual flush was not done and you have crud in the calipers. If you have the time/space then pull the calipers and check the rotor runout and general condition. Surface rust from sitting is not a big deal, but warpage and gouges are.

If your car is indeed typical, then the fuel is wet/dirty. Do the biocide after the rods and brakes (search on those, fuel filters, and algae in the tank). Then drive it hard for a month to burn out the carbon in the engine, and troubleshoot the vacuum stuff as you find time. Keep spare fuel filters in the trunk. Then do a compression test that won't lie to you. By then you'll be addicted.

artpb · #5 10-07-2003, 10:25 PM

Welcome. Start with Diesel Purge followed by new filters as psfred suggests. Get fresh fuel in the tank asap along with a stabilizer if the vehicle will be hanging around quite a while.

Now that you feel good because somethings been done, go and review Thomaspin's website (Sticky). If you can't find something else to do then bail out

BigMikeT57 · #6 10-08-2003, 02:01 PM

Thank You Gents,

Will definately start with the Diesel Purge/Algicide treatment.
Then if all looks good will move on to brakes/front end.
Don't plan to put it on the road 'tll spring. How long can diesel
sit, without stabilizer?

Also, have refurbed the brakes on the 420, no sweat, but never
rebuilt calipers. Have read the posts, but have seen different opinions on DIY or not. Any suggestions?

Thanks,
Mike

psfred · #7 10-08-2003, 08:12 PM

Rebuild calipers to me means pull the pistons and replace the seals only. Don't take the halves apart, and do not use any abrasives in the bores or on the pistons. The only exception is if there is some corrosion in the bore OUTSIDE the piston seal -- this can be VERY CAREFULLY removed with abrasives, but you must then remove any trace of abrasive material from the caliper or it will eventually cause the piston to seize.

This is not a diffucult job unless the pistons are well and truely stuck -- use the brake pedal to remove stuck ones, not compressed air (leave the caliper on the hose, clamp one piston in place, then pump the pedal (all other calipers and pads in place) to force the piston out. A stuck piston can let go suddenly with enough force to blow through a wall, and can easily kill you if it hits you in the head -- use low pressure and put a block of soft wood in the caliper to prevent the piston flying out if it lets go suddenly if you use air to free a stuck one. Best to use a "blower" attachement with a rubber tip so you can regulate the pressure easily.

I'd bet all the rotors are thin, the pads have hit the anti-rattle spring, and the pistons are stuck, some more than others. Classic "cheap" brake job on a neglected car.

Peter

BigMikeT57 · #8 10-08-2003, 10:06 PM

psfred,

You make the caliper rebuild sound easy. If I can do a timing chain on the 420, I guess I can pull this off.

Stopped by PepBoys tonight to look for Diesel Purge. They only
had something called Diesel Kleen, which looks like an injector cleaner meant to be added to a tank of diesel.
Anyone heard of Diesel Kleen, or tried it?

Thanks to all for your encouragement.

Mike

P.E.Haiges · #9 10-08-2003, 11:28 PM

Big Mike,

How long will Diesel fuel last? At least 10 years.

I say this because I some fuel oil sit in a 275 gallon tank for at least 10 years and when I got around to using it, it ran just as good as fresh stuff.

The only problem with older or any Diesel fuel is if it has algae in it but you have to have a source of contimnation. No source, no algae. I never had a problem until I got some contaminated fuel somewhere in the south. Its usually not a cold (northern) climate problem.

P E H

BigMikeT57 · #10 10-08-2003, 11:58 PM

Thanks PEH,

Was wondering, since I keep reading posts that mention fuel stabilizer for diesel.

dabenz,

The Camry was a gift from the in-laws (only 24K miles!). My wife is working on them for the '03 Camry that they replaced it with!

Is the MityVac "the" tool to have? I have a Sears vac gauge, is there any added benefit to the MityVac?

Thanks all!
Mike

BobK · #11 10-09-2003, 07:27 AM

Mity vac will let you create your own vacumm without the engine running. You can isolate one section of the vacumm system and test it. Cheap tool (get at autozoo). Since MB uses vac. to do so many things, it really is one of the best tools to make quick work of troubleshooting.
Another thing you want to check pretty quick is the boost line from the manifold to the ALDA. They tend to fill up with crud and you get reduced power when that happens. On the back of the intake manifold will be a plastic line with a banjo fitting. This line runs over to the firewall to the overboost protection solenoid and then to the top of the injection pump. Disconnect the line at the manifold and at the solenoid and see if it is full of crud. Just clean it out with some cheap carb cleaner. There are two washers at the banjo bolt. Be carefull not to lose them. I have an '83 300D so I can visualize most of what you say pretty easily.
Do a search on transmission adjustments and you will find out all about the way vac. is used to shift your transmission. You will see how a vacumm leak can make a lot of things wierd including the transmission. With a little work, that 3.0 litre engine is about the toughest thing on the planet.

Rick Miley · #12 10-09-2003, 02:41 PM

Hey, let's not help him get any more power until he gets the brakes fixed!

BigMikeT57 · #13 10-09-2003, 03:14 PM

BobK, Thanks for all the good advice on the MityVac. Will pick one up.
Rick, Who needs "stop", when you don't have "go"?

Seriously, all safety issues will be addressed b4 even road testing the beast.

Mike

#14 11-14-2003, 02:50 PM

My 1982 300TD with 212K miles had similar symptoms and spent many dollars on injectors and other components. Problem was solved 1 yr. later when I got around to regapping valves. PO had informed me that he had just done the job, but must have performed incorrectly. You will need feeler gages and replace the cam cover seal ($12) each time you perform this operation - I'm fairly slow and meticulous - this job took me about 5 hours. I have another post that follows this up in more detail under Colombian Coffeebean.

BOGDAN · #15 11-14-2003, 05:20 PM

If you need help you can email me at bxsega@yahoo.com and iwill give you somme help------i live in long island to