No Compression and No Fuel
 

I received a 73 220d from a family member who let it sit for 20 years. It will not start. I only have between 200 -220 compression on each cylinder and the delivery valves don't seem to be putting out much fuel. I do have a little fuel to three of the injectors but one is bone dry. The valves were adjusted, fuel filters have been replaced, as well as the hand pump and the injectors were rebuilt.



- Will it ever run with that low of compression?
- Any advice on getting compression up? Wet or dry doesn't get much better, I tried putting some seafoam down the cylinders and letting them soak a bit but compression got no better.

- Any advice on how to get better performance out of the delivery valves?



All I know to try next would be some Restore Engine Restorer and see if that helps the compression?

My suggestion would be to see if it will run on WD-40 sprayed into the intake. The reason for the low compression can be determined using a leak down test where each cylinder is pressurized while at top dead center and listen for leakage into the exhaust, the intake, or the crankcase. Hot air from a heat gun into the intake while cranking is a good way to start a reluctant diesel.

YOu can pull it to get it started. It will need fuel though to run.

Resurrection
 

Yes, it will run and run O.K. with that low compression, as mentioned dry the inverted WD-40 in the intake .

Often the valves get surface rust on the sealing surfaces from sitting and the compression comes back after being run a while .

220 is on the low side but that is to be expected for an engine which sat that long. Maybe, and that is just a maybe, the compression will improve if and when you get it to start and run.

What procedure are you using to attempt starting?

The proper procedure is to:
1. Turn ignition to "run" or #2 on the switch
2. Pull the start lever ("Gorilla knob") until you feel a spring resistance.
3. Hold the knob in this position until you see the heating element glowing in the chrome aperture ("Salt shaker")
4. Pull further on the knob to engage the starter motor.

Crank for a maximum of 30 seconds preferably only 10 to 15 seconds. If the engine doesn't fire then repeat steps #2 through #4.

The minimum for compression listed is 213 p.s.i. so you are on the low end of the scale but that is for an engine which is in a running condition not one which has been sitting for years.

Good luck!

My old Chiltons repair manual states that 220# is needed for reliable starting. They will run with a lot less if you can get them started.;)

Thanks everyone for the replies! I have to work tomorrow, but I will hopefully be able to get out to work on it some Tuesday, and will give Wd40 a shot.

I may be wrong on this but...have heard that WD-40 of recent years has been reformulated and won't work as a fuel to start engines...anybody know for sure???

To the OP 200-220 seems quite even and makes me wonder about 1. Is the gauge known good, and 2. is the valve timing correct?

Good luck and keep us posted.

I adjusted the valves. The gauge is a brand new tester from Harbor Freight. I assume it is correct. I'll respond on Tuesday when I get a chance to work on it some more. Thanks.

The China Freight testers are extremely well known for being bad out of the box. They have a schraeder valve in the adapter of the tool that typically leaks or is missing entirely and can give false readings. Some have reported the gauge being very badly off. Just something to be aware of. Try swapping the valve from a different adapter and see if you get a different result.

s2s, I understand the valves have been adjusted, that was a good move. Has the valve timing been checked i.e., are the camshaft and crankshaft in time? Crank on zero and camshaft marks lined up? If you know it was running well and just parked it can be assumed ok.

Good luck!

Harbor Fright Compression Testers
 

YES ! :mad: .

I was trying to diagnose a 50 year old Honda Moto's no start condition and the H.F. tester said only 65# so I rebuilt the top end, re assembled it and still no start and little difference in the kick stater pedal's resistance so I re tested, after new valves and piston it only showed 5# more so I tried another tester and Lo ! 150 #, dammit .

I understand the need for cheap tools that may not last long but broken right out of the box ? . that's piss poor .

Sounds like you may also have a piston in an element stuck at the top. In the injection pump.

I had no luck with the WD-40. Above it was mentioned that WD-40 may be less combustible than it use to be and perhaps that is why it didn't work for me?
As for the Harbor Freight tester, yeah I know, but it was the only place I could find that had a diesel tester, considering the low miles and history I know of the car I assume that it's just from sitting and that the compression will come back if I can get it started, but so far no luck.

Main issue is still that I am not getting fuel out of all of the delivery valves, 1, 2, and 4 are moderate fuel spray, but 3 is bone dry.

Try Pam cooking spray to start it. Try Marvel Mystery Oil in the engine (from the top and in the oil) to see if it's just stuck rings. That will free it up if so.

If you are getting fuel in three of the four cylinders, it should run. I don't know your specific engine, but most reluctant diesels will start if you supply hot air into the intake. Remove any plastic and any filter so you can direct hot air directly into the intake while someone cranks the starter. Even a hair drier can be helpful if you don't have a heat gun.

is number 3 injector line free of any blockages?
try swapping #3 injector with one of the others.
or try mmo in #3 delivery valve.

+1 on the cooking spray, I found it works really well last time I got air in my system.just fog the intake, then crank.

Propane.
Propane torch (not lit obviously) fill the intake with gas. If it fires at all, then do it again and leave the torch on to see if it will run.

No blockage in the line, fuel literally won't come out the top of the 3rd delivery valve with all lines removed, but does the other three.


I will try what was suggested above and report back. Thanks everyone for the replies!

The Pam didn't work for me. I can try the hairdryer thing tomorrow, but it is 91 degrees here today and I let the glow plugs warm up for a considerable amount of time before cranking so I am skeptical it will make much of a difference but I will certainly try any suggestions at this point.
I did pop out the #3 delivery valve that is dry and the plunger is completely stuck inside the delivery valve, like it's one piece if it wasn't for the diagram I was looking at I wouldn't of realized it was two pieces. Soak in Marvel Mystery to unstick them or any other suggestions? I don't want to be too rough with them but they are really bonded together, guess that is one reason I don't have fuel coming from there.
Thanks

Nothing has worked so I have turned my attention to the injection pump since I still was not getting fuel from the third delivery valve. I removed the delivery valves and poured Marvel Mystery in and am soaking it. The third plunger wasn't moving so I gave it a tap and I could feel it slide down. Now the barrel moves up and down but I can't see the plunger moving. All three other plungers seem to be moving freely.
I assume once you assemble everything it prevents the barrel from moving up? But from what I read the concern is that it isn't seated properly in the slot?

IP Fiddling
 

O.K., let it soak a few days, then remove the delivery valves making sure to keep the parts matched and look closely at them .

I've discovered rust on quite a few, they're still available new from the M-B Classic Center, about $40 each IIRC .

I tried used ones and found them in matched sets with no visible corrosion etc. but that didn't really help much so in time I replaced all five sets and then spent a lot of time fiddling with the ALDA adjustment, this reduced the fuel smoking and made the engine run *much* better, whomever I gave that IP to says it's fine so I suggest trying this before bailing out and replacing the IP completely .

In the end I have a good, strong running OM617 engine that blows oil smoke slightly at all speeds, loads and RPMs :mad: .

It appears to me that you have the time, patience and inclination to work through this, welcome to the world of old machines .

I'd offer you some used delivery valves in matched sets that have no corrosion but I'm pretty sure I tossed them all away .

My thought on lazy or semi sticky element pistons. To force them to seat back in. Basically free up enough. One might consider disabling the check valves.


No the engine will not run but the back pressure will certainly push the pistons back down. As stated do not mix up the part of them you remove to enable this.


If after this when the deliver valves are engaged again. If the elements are damaged or not depends on the amount of rust or whatever was sticking them originally.


When the element pistons are normal in friction with the bores. I have felt the pressure present just before the delivery valve closes pushes them back down in service. If the delivery valves are good this may not be enough for sticking element pistons. Depending on what stuck them will perhaps depend on if the pump is still serviceable or not. After they are free.


Some of this of course is pure guesswork. Or speculation. I can see very old fuel oil changing over time. In a pretty much dry injection pump and becoming very sticky or gummy. The fit of piston to bore is probably a lapped finish and it may be hard to find a solvent that can penetrate that tight of a fit easily.

Thought I was getting somewhere, can watch the pistons going up and down when cranked over, but nope, put it back together and still not getting fuel from number 3 and not enough to count from the others.
By the way while I was sitting inside cranking it over I noticed the odometer, 48,000 miles, that's it, clean car. But the pump must me pretty gunked up.
I guess I have to dive more into this pump to free it up. I haven't taken the side cover or back cover off the pump yet to see if I can slide the rack, but I guess that is next.

1. How much should those pistons be going up and down?
2. What is a good way to lift those barrels out from the top?
3. If I take the pump out, how hard is it to get back in and retain timing?

http://www.peachparts.com/shopforum/attachments/diesel-discussion/159111d1597785626-no-compression-no-fuel-220d-pump.jpeg

I either have more problems or less problems than I thought.
Somewhere along the way with all the cranking over to get air out of the system I ran the pre filter dry. Tried using the hand pump and nothing. Its the new style black Bosch. Is there anything else that could cause the hand pump not to work other than the hand pump itself?

Haven't followed the entire thread, but did you check the tank filter? If ya got a good flashlight, you can pull the tank sender out, look in there. Is there a ton of crap in there?

Also, why not just get a replacement injection pump? I'd make sure you're good up to the injection pump, then just swap it. Might be more expensive, but the injection pump has a bazillion pieces and isn't an R/R kinda thing

Run a hose from a container of fuel as directly as possible to the IP.

I have a water bottle filled with diesel and a hose to the hand pump and no fuel is drawn when I use the hand pump.
Yes the screen in the tank will need checked eventually but right now I have the tank isn't being used the bottle is.
Injection pump is an issue as stated earlier in the thread but now I realise I am not even getting adequate fuel to the pump because the hand pump isn't drawing fuel and I can't bleed the system properly without the hand pump.

Can you remove the primer pump and bench test ?

To replace the primer pump, and maybe the lift pump, in the system, use a low pressure electric fuel pump from your bottle to the IP.

I haven't removed it from the car but I disconnected the lines and worked the pump with fuel still in the reservoir and hooked to a bottle of fuel, when I pressed the hand pump it didn't move any fuel, no bubbles no squirting out the outlet to the canister fuel filter, nothing. Also the hand pump which is the black Bosch style seems very hard to push and doesn't fully spring back. I am not familiar with working on Mercedes or diesels for that matter, but something seems wrong here. I have seen rebuild kits for the 2 bolt lift pumps like mine has, and all metal Monark hand pumps but the only source I can find for these are mercedessourse website which seems a bit over priced.

Blocked or frozen return valve maybe.
loosen the banjo bolt on the engine side of the IP and see if you can prime.

You may have a frozen check valve in your lift pump, which would completely eliminate any pumping action. If your lift pump isn't getting any fuel to your IP then that could be your issue. If this was my engine, I'd be rebuilding the lift pump before messing with the IP any more. If I had a spare electric fuel pump laying around, I'd plumb that in as a lift pump and see what happens.

Good luck.

I agree with above that I need to focus on lift pump first. I was able to order a rebuild kit for the lift pump from the local Mercedes dealer, they said it was the last one in the country.

I can't seem to find the gasket for where the lift pump mounts to the IP anywhere, what would be the best material to make one out of, or does anyone know where to get one or a part number? Thanks

Google search Mercedes 300sd fuel pump gasket,one Co. has 90 some.

Monark Primer Pump
 

I bought an all metal pump on Ebay from this seller:diesel-parts9000. He is in Germany and is not responsive to questions about whether the pump will fit a particular model car.However the pump is inexpensive ($6) even with 1 week delivery ($11). I think these small pumps are very common and are a pretty universal fit.They do move alot of fuel compared to Bosch,black pump.He also sells Monark fuel injector nozzles. Hope this helps.

Update of where I am now, I finally got a rebuild kit for the fuel pump. It helped a lot, but still not running, closer than I have gotten the car before though, it starts but then quits, and once it quits it will not try catch again unless I get out prime the pump and do the glow plugs again.
Here is a playlist of a couple attempts. Is it running out of fuel?
Also I think the starter is going bad you can hear it in the video labeled "Bad Starter?" sometimes while cranking it whines and stops. Is there any danger of harming the flywheel? Just want to know if I should replace the starter before making anymore attempts? Thanks!
https://www.youtube.com/playlist?list=PLvgmjy_Xf0abGLVKvFW_SkF9jYdsJCbf6

Got it running. Sounds rough but running.
Next up I am going to do a diesel purge, readjust valves, oil change, and clean tank. Probably change fuel filters again after the diesel purge. This thing sat since 2003 so.

https://youtu.be/lV-OB4f03GI

Starting Woes
 

#1 : the starter sounds O.K. in the five videos, the battery isn't fully charged and you failed to keep the throttle fully depressed each time it tried to start, a common newbie mistake ~ once it's running you MUST keep the throttle pinned until it's running on all cylinders .

Yes, it sounds too loud and too fast but there's a governor inside the I.P. that prevents excessive RPM's , it needs to run a while at a goodly clip to self bleed all the air out .

Looking at the last video where it's running O.K., the clear plastic line returning fuel to the filter, shows no bubbles .

Looks like a very nice car there, if you're careful and deliberate that original paint will buff out and shine up nicely, remember to WAX IT to keep it looking sharp .

Remember : the clear plastic fuel intake screen needs to be CLEAR not translucent, this is so you can spot fuel problems (air intake leaks, fungus etc.) before they bring the car to a halt .

The devil is always in the details .

Thanks Nate! Yeah I never had a diesel before so thanks for the input!

The Basics
 

Not many W114/115 owners / enthusiasts her but an amazing amount of collective knowledge so ALWAYS ASK ! .

I don't know if there's a factory service manual in CD - ROM or not, they do show up used here and there regularly, the good thing is : most will be dirty / dog eared / greasy so the "serious collectors" who lever read anything anyway, won't touch them, allowing you to get a good deal if you bide your time and as after the E-Bat sale is finished with no bids....

Also there are Glenn's, Autobooks, Chilton's and never forget H.B.O.L. :rolleyes:, they're a cheapo crummy shop manual but are very helpful to get up to speed .

In case this is your first German vehicle you should know that German cars require much more touching than do any others .

This doesn't mean repairs per se, it means they like to be looked over and checked on a regular basis, 90 + % of the time a simple thing may need a quick adjustment or whatever, basic tools are the norm so don't be scared .

Read up and check on how to get that injection element piston moving again. Or delivery valve working. A light spray of quick start with the glow plugs disabled. Do not neglect to do this.


Should get it running. Todays quick start has a lot less either in it and it has been used to start old diesels forever. Just no glow plugs activating. The block heater on does no harm for the attempt as well. You mist some of the quick start over the intake system. Not going crazy with it.


Personally I would want tp find out if the injection pump can be made to work properly first. If not then what is faced. Remember that this engine is capable of running. It is just not usable with the injection pump as it is.

Diesel Purge. Not as much smoke as I expected.

https://youtu.be/HhoCj5BgnOA

Diesel Purging
 

You need to constantly change the engine RPM's to properly do a Diesel purge ~ best way is to drive it around the neighborhood , under load .

You should also place a clear plastic fuel filter in the return hose so you can see what's being cleaned out.

NAPA/WIX # 33001 or equal .

You're getting there, pretty soon you'll have a nice driver on your hands .

Thanks Nate, I did rev the engine some (not on video) but I will run another can of purge through it once I am able to drive it, but I need to work on the brakes, tires, and tank, plus get a plate before I can drive it on the road.
Since the car sat since 2003, do you recommend cleaning the tank? If so how? Thanks again.

Fuel Tank Cleaning
 

It depends on what comes out when you remove the in tank strainer ~ .

I'm *think* the tank is underneath the trunk floor so I'd prolly remove it and clean / de rust it @ home, not terribly hard to do, you'll need to jack up and safely block the car first .

If you live in an apartment or condo you may have restrictions on your options .

I often place two inline fuel filters before the transfer pump, the first will be a clear plastic screen and the second will be a larger clear plastic paper element one like the WIX/NAPA/ 33001, this after you've removed and gently cleaned the in tank screen .

See what you've got and I'll detail the cleaning, it's a bit messy and will kill the grass so choose your work site carefully .

I recently cleaned and de rusted a 1950's VW fuel tank that had sat since the 1980's, it was rusty and really bad looking inside, no one wanted to touch it after looking in, I cleaned it at home in a few days and it looks _new_ inside, not a speck of rust of crud left .

Easy enough to check on a /8 AND a good reason to buy another toy, err, tool. Remove the fuel sending unit and inspect using a borescope.

The primary strainer, located in the bottom of the tank can be a bugger to remove. I usually end up using a 1/2" breaker bar AND a three foot "cheater" bar to break them loose. I use an old spark plug socket, inverted, as the hex to fit the plug. Remove the strainer, or at least break it loose, with the vehicle on the ground for safety reasons.

The tank itself is easy to drop if the mountings are not rusted. Have the rear of the car lifted fairly high to give you room to maneuver the fueling neck.

Ok, I ordered a new tank screen, I will drain the tank and pull the screen and see what it's like.
By the way what engine oil would you recommend for Pennsylvania? Winter can be quite chilly, but it's not a daily driver so I doubt I will be driving it if it's below freezing, at the same time there is no AC so I doubt I will drive it if it's above 90 in the summer.

Thanks again everyone!

Don't be in any hurry to buy new parts ~ the screens are easy to clean using inexpen$ive de greasers and a soft bristle toothbrush in the sink .

Same with the clear plastic fuel intake screens under the hood ~ I carry spare ones and foolishly threw away the best ones that had brass inlets, now I know I can clean them out spotlessly clean in a few minuets as I wash my hands, leave to dry and put back in the glove box...

Sadly the brass inlet screens are no longer available .

I keep hoping to find one on a junker .

What oil...15W-40 C rated diesel motor oil. Motorcraft 15W-40 adverts 1000ppm of ZDDP. The ZDDP referred to as zinc is good for engines like yours with flat sliding camshaft followers. Delo and Rotella are well respected but might be lower in ZDDP.

Good luck!!!

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Drained the tank and got the strainer out, looking in the fuel fill neck it looks like a lot of cleaning is in order.