68 250sl runs much better....90%...

[amg65ri]

Got the car running. Engine = Check   Brakes = Check  Wipers = Check.   Power = where did it go???

Not sure what is the issue, but I think it could be timing or the fuel injection...

Here is what I know...

Facts:
1:replaced, fuel filters, cleaned tank, new fuel, and hoses.

2:replaced plugs, wires, cap and checked points (working)

3: Changed oil, coolant, tranny fluid and diff.

4:Car idles, revs to 4k smoothly and starts/shuts off perfectly.

Issues :
Car has no power when clutch is let out, especially up any slight incline. I can get it to drive in first 2 gears and reverse but not much more than 20mph.
RPMS drop and it feels like an ebrake is on. (ebrake is not on, car rolls easily) i am not sure what to test first.

1:Timing?

2: Compression?

3: Clutch?


any help or experience would be greatly appreciated... car has sat garaged for years so it could ba a number of things...


ben

[ja17]

Sounds like the rack in the IP may be stuck. Remove the round access cover in the front end of the injection pump and check to see if it moves back and fourth.  Do you need more information on this procedure?

[amg65ri]

Hello Joe,

Thanks for the suggestion. I am new to these cars so any help would be great.

UPDATE://///

I removed the 6 lines that go to the injectors (removed the Injector pump side connections)

I quickly found that the line numbers 1 & 2 flow a small amount of fuel when the car turns over (1 & 2 being the closest to the firewall) 3,4,5, & 6 produce no fuel from the top.

I believe that my lack of power was due running on 2 cylinders.... What should I do next? I am off to get a few 4mm bolts to thread into the rack cover on the front of the pump to see if i can move it.

next stop home depot.....

[Benz Dr.]

Your car won't run on two cylinders - it would stall. You did say it runs smoothly up to 4,000 RPM so I don't think it's the pump. It would miss fire due to a lean condition as the fuel ratios would be all messed up.

I half supsect that both your vacuum and mechanical advance is stuck inside of your distributor. The engine will start and run well and might even idle well. If the pump isn't working right it would show up as a miss even at idle. In this case, as soon as you increase RPM's the engine will fall flat without timing advance. It will rev up to a certain point and will not go much higher - it won't matter how much throttle you use or how long you hold it open because that's all you'll get.
Try moving the rotor to see if it will move and if it springs back. If either the vaccum or mechanical advance it working the engine will run but will lack real power and it will use a lot more fuel. When both are not working you will have a condiction similar to what you have right now.

[amg65ri]

Your car won't run on two cylinders - it would stall. You did say it runs smoothly up to 4,000 RPM so I don't think it's the pump. It would miss fire due to a lean condition as the fuel ratios would be all messed up.

I half supsect that both your vacuum and mechanical advance is stuck inside of your distributor. The engine will start and run well and might even idle well. If the pump isn't working right it would show up as a miss even at idle. In this case, as soon as you increase RPM's the engine will fall flat without timing advance. It will rev up to a certain point and will not go much higher - it won't matter how much throttle you use or how long you hold it open because that's all you'll get.
Try moving the rotor to see if it will move and if it springs back. If either the vaccum or mechanical advance it working the engine will run but will lack real power and it will use a lot more fuel. When both are not working you will have a condiction similar to what you have right now.

I understand your point. The rotor and cap do work though. The advance also seems to be fine... I can also confirm though that only 2 of the cylinders are getting fuel by watching the pump only pump from 2 of the lines..   I have attached a link of a video for you all showing the car running on 2 cylinders. It just does. I started this way to prove it. I can also drive it around (but dont)

Repeat, the car runs on 2 cylinders......   http://www.youtube.com/user/RIH1USA#p/a/u/0/k_yF8J4q8iU

Please, let me know what i can do to unstick the 4 injector pump fittings closet to the front of the car. Not sure if the rack is stuck (it is pumping  the 2 lines closest to the firewall)

[ja17]

Yes, thread the screw into the end of the rack and see if you can move it back and fourth.

[amg65ri]

Yes, thread the screw into the end of the rack and see if you can move it back and fourth.

Ok, got the thread screwed in and it appears it is stuck... I can move the rack about 1/8 of an inch in each direction...

1:Any ideas on what to do to get more travel?

2: Also how hard should I try to move/pull it?

3:is it ok to hammer it in and pull it out by prying?

4:What chemicals can/should i through in there to loosen things up?

sorry for all the questions...

[ja17]

Hello,

A stuck rack is normally caused by one or more of the pistons in the IP being stuck resulting in a stuck Rack.

The first step is to remove all six injection lines on the IP. Do not remove the fittings in  the IP itself yet.  Crank engine at full throttle and watch to see which cylinders of the IP produce fuel. The ones that do not produce fuel are the ones that are stuck.

Get back with us for with results.

[amg65ri]

Hello,

A stuck rack is normally caused by one or more of the pistons in the IP being stuck resulting in a stuck Rack.

The first step is to remove all six injection lines on the IP. Do not remove the fittings in  the IP itself yet.  Crank engine at full throttle and watch to see which cylinders of the IP produce fuel. The ones that do not produce fuel are the ones that are stuck.

Get back with us for with results.

OK, so the rack is stuck...  Only 2 of the lines produce fuel. The 2 closest to the firewall produce fuel and the 4 closest to the front bumper must be stuck...


whats next?
thanks

[ja17]

Remove the fitting in the IP from the four that do not squirt. If any are loose this is could be the issue. Otherwise, after the fittings are removed the round check valves in the pump can be pulled out (they are threaded on  the outside. Find a fitting that can screw on them so you can pull them out.

Once the check valves are removed you can look right down on the IP pistons and cylinders. You can crank the engine, and if the little plungers (pistons) in the center do not move up and down they are stuck. Remove the fuse for the electric fuel pump before you do this or you will have fuel everywhere. Try soaking down the cylinders and pistons with penetrant.  Gently tap down on each piston with a soft metal (alum. - Brass) or even a hard wood. A gulf tee can work if you grind the end nice and flat. Be gentle. Only the small piston in the center will move up and down. Some may move. Keep turning the engine, exercise the rack and keep tapping the pistons and turn the engine.  If the piston is on the upstroke, tapping on it will not move it. So do not get carried away. if it does not move turn the engine and try again.  Eventually they will begin moving up and down on their own. When this happens the rack will become free also.

If problems persist you may have to let penetrant soak or switch to alcohol which is best for fuel varnish.

I am sure you will see some results right away.

Caution !!  During re-assembly the 19mm fittings in the IP must be torqued in at around 18-20 ft lbs. of torgue. No more or less!

Keep us up to date.

[amg65ri]

Thanks Joe,

Just so I am clear. I need to remove the 4 stuck  "A" 19mm fitings (from my picture below) and tap on the 4 pistons "B" gently after cranking the motor and removing the fuel pump fuse.

Questions:
1:How do I remove the part between "A" and "B"?  I dont see any threads on it. Can you shoot me some specs on the tool or fitting used to remove it? Does it just pull out?

2:Should I remove "C" the access cover and spray alcohol or penetrating oil in here?


thanks

[ja17]

Yes remove the fittings "A".  Removal of the cover"C"  is not needed at this point.  The check valve inside has a fine metric thread on its outside. The check valves just pull out.  I nave a clutch hydraulic hose which has the same thread from one of these cars. However if you go to a harndware store and get a brass fitting which will is close, it will thread on one or two threads and can be used. The threads on the outside of the checkvalve are only there for its removal, so you do not have to worry about them getting a little damaged. You can also gently use a couple of small screw drivers on each side to gently pry them loose and out. B in the picture is actually the cylinder. The small cylindrical piston is in its center and has a divit in its top. The piston is  only about 5mm diameter.  When the piston is stuck, the cylinder may move up with it when the engine is turned. The cylinder is "keyed" in a set position. If the cylinder does move up with the piston, the cylinder must be kept oriented in the same direction and tapped back down. You will see the vertical slot in the side of the piston which is keyed to a pin in the IP.

OK, as the engine turns the pistons should move up and down. The cylinders  B should stay put.  Also,,,,,,,,,,when the rack or linkage is moved the little piston in the IP actually turn or twist also ! !    When rust or varnish causes a piston to get stuck the piston will not twist and this is what causes the rack not to move.  A stuck piston will usually move to the top of its cylinder B then stay at the stop instead of moving back down when it should. The tapping on the piston will cause it to return to the cam below. A spring normally does this. But if the spring cannot overide the rust or varnish the piston sticks at the top. Take your time use lots of penetrant or solvent. Be gentle, because if the piston is resting on top of the cam lobe it will not tap down until the engine is turned and the cam lobe below in the IP, is down. Watch for a cylinder B moving up it will need to be set back down. Eventually things will start working on their own. It is important to torque the fittings "A" dpwn when finished to 19 -20 ft. lbs.  The cylinders in the IP must be keyed and oriented correctlyif they have moved upward before torquing the fitting down.

Keep us up to date.

[amg65ri]

Joe,

Thanks for the help. i managed to free a few more of the pistons ( i think because as I tap them down they do come back up... I am up to 40 golf tees on the first Piston (closest to front of car...)  though not sure if it will ever go down.... also the rack will still not move....

I did manage to get alot more power out of the car. but i know it cant be correct if one of the pistons is still stuck.....  i have soaked and reassembled many times over the past few days.... still frozen a bit... not sure if I should just wait...

here are some pics... some are a few days older when I was cleaning out the fuel system.

[amg65ri]

Here are the Ip dissasembly pics... I wish I could get the first piston to go down... i think it is seized....  if I try to fill the chamber with penatrating fluid is just leaks into the main fuel supply....    any ideas?

[dseretakis]

Maybe try a more potent penetrating oil? ATF/ acetone mix, Kroil, etc?

[ja17]

Hello,

The engine will not run well at all unless the rack is free.   The rack will not free up until that first piston is also working.  Be sure to turn the engine to a different position since the piston may be at the upstroke when you attempt to tap it down.  You may have to find a brass rod to tap with. The wood may not do the trick on a tough one like that. You  are close to success. Keep at it.

From the pictures I cannot see the inside lower rubber seal in your oil filter canister? Make sure it is there also, make sure the upper seal is (above the filter) is up in the filter holder. Look in the tech manual for a good break down.

It looks like you are using a domestic after market oil filter. They are usually about an 1/8" shorter than the original oil filter They will not seal correctly when installed and dirty oil will leak past the oil filter.

Keep us up to date.

[ja17]

Your IP looks very "crusty" inside. Be sure to blow away all the dirt etc. with a little compressed air before re-assembly. Yes, find a soft metal rod (aluminum or brass) to tap the piston. Be mindful that you may have to turn the engine before the piston will go down. Be gentle. Try tapping, turn engine, try tapping turn engine, repeat as needed. You may attemp[t  to move the rack in and out, this can help a lot.. You can tap the rack back then pry it fworward using the threaded screw.  You will see things start to work. Once you get any movement at all the penetrant will go to work on the stuck parts. Also soak those check valves in a little penetrant before re-assembly

[dseretakis]

Joe, I'm learning so much from these posts! Is the process similar for the 220SEb coupe and Adenauer injection pumps? I have both those cars but they have been sitting for a few years so I'm starting to get worried.

[ja17]

Hello dseretklis,

Yes, very much the same.  The main difference is that the 220SEb pump and the Adenauer pumps use a different check valve under the fitting. It is a "cone and seat" type valve very similar to the one in the CSV if the W113 cars. The 230SLs also use this type of valve in their IPs.   The Adenauer pump also has a leather vacuum diaphragm which controls the rack via intake manifold vacuum.  Stuck pumps can be freed and cleaned up in the same manner!

[dseretakis]

Wow. This  great to know. I was always under the impression that an IP rebuild was in order once it froze up.

[Benz Dr.]

Not to take anything away from Joe's usefull information but you may still need a rebuild even though the injector elements free up. Sometimes it's a matter of calibrating the pump but if it's been left seized in one place for years all of that rust can really mess up the fine tolerances inside of the pump.
You may be lucky enough to make it all work properly but it's not something to count on or expect. Think of it as putting off the inevitable. The pump is likely compromised to some degree and may run OK for a while. How long is anyones guess.

[ja17]

Hello,

A major IP rebuild,  depends on each situation. Severe damage from water and rust can result. The length of time and the amount of water involved can be the determining factor.  Sometimes just varnish from dried out fuel is the cause of a stuck pump and no permanent damage happens. I like to use plain rubbing alcohol to clean fuel varnish. It works better than any other solvents and cleaners that I have tried.

I free up IPs  from stored cars all the time. Most respond and run fine.  I know of one major IP re-builder who claims most IPs sent in for re-builds are functionally ok, and just stuck of extremely out of adjustment.

[dseretakis]

 Does today's fuel with ethanol facilitate rusting of the injection pump? Does sta-bil help in this respect?

[amg65ri]

Ok Joe,

I got the first piston moving freely on its own and now the rack moves in and out freely!!!

The rack really does move in and out a good 1/4 inch + in each direction....  So after cleaning out all the crud.... i flooded the rack and sucked out all the dirt/grime a few times with wet vac and "sea foam" deep creep.

I might add that I had better luck with the sea foam deep creep than I did with pb blast... I also had better luck using a punch on the stuck piston than the golf tee's....

ok so heres what i did next...

1: clean out check valves
2: reassemble and torque correctly
3: remove spark plugs
4: turning the engine over I can see that the fuel is pumping out just fine.
5: next I lossened the fuel injector lines at the fuel injectors.
6: I can see the fuel making it to the injectors...


The car will run for about 2 minutes if i start it with some starting fluid. I am not sure what is wrong yet.


Perhaps I need to remove the injectors and clean them? any ideas?

[ja17]

Hello,

Does it accelerate at all ?  You may be running into the issue with the WRD at this point. Try to do a split linkage test on the engine before it shuts down.  This will tell you if you are going lean or rich.

Congratulations on your progress !