I need advise. My vacuum pump failed this past week while my wife was driving the car. It apparently broke while on the interstate and presented no real symptoms until it was time to hit the brakes (i.e., lost power breaks) Since she was out of town, we figured a vacuum line had just come off or the like....long story short, she continued with her trip and just used a lot of leg strength for brakes and the shut off level on the engine to turn it off...the car probably went another 100-150 miles before getting back home.

I've since determined it was the vacuum pump that was the culprit. Got a new pump and in the process of putting it on now. Removed the old pump and sure enough it came out in pieces. I'm pretty sure I have all the pump parts accounted for, but have now discovered the stroke curve on the injection timing device appears non-smooth and damaged. Question #1 - I assume if it isn't smooth as new, it needs to be replaced too, yes?

I have a parts engine and just removed the timing device from it. The part looks to be in perfect condition. I've read the MB bulletin (07.1-8014, attached) for removing and installing a new timing device which indicates you remove the camshaft sprocket and chain tensioner to provide enough chain slack to remove the timing device (i.e., don't have to unlink the chain). Everything makes sense until the last few steps regarding locking the injection pump and any IP adjustments. I don't have the locking tool nor really understand how to do that. Question #2 - Is there an alternate way or any tricks to remove/install a timing device without locking the pump and having to re-time the IP? Question #3 - with vacuum pump already removed, any idea how many hours a good mechanic would take to remove and replace the timing device, ballpark)?

Thanks for the help. BTW, this is my 2nd round of vacuum pump failure.
svengruber

Attached Files

07.1-8014.pdf (508.4 KB, 224 views)

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1993 300D 2.5T
1968 280SL - sold

In theory locking the IP with the about $36 Tool is supposed to keep you from having to retime the Fuel Injection Pump.
If you did need to retime the Fuel Injection Pump it is supposed to be done with the A&B Light or the RIV method. There is no Drip Timing spec for your Fuel Injection Pump.

Likely what is confusing is the Timing and also the installation of the Timing Locking Pin is done at about 15 degrees after top dead center of the compression stroke. (There is a sticker on your Car that has the specs for your specific Enging.)

Below is a pic of the Timing Locking Pin.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

I was looking at the pdf and found this caution (see pic). The Bolt that retains the Timiner Gear is Left Hand threaded.

Item 7 also has a Pin needs to be removed and a Black Arrow in the diagram points to the pin.

a cross from step number 10 is a Pic that shows a tool with a number 25 on it. That Tool is used to rotate the Camshaft of the Fuel Injection Pump when the Fuel Injection Pump is out of the Engine. You could do the same thing with some Channel Lock Pliers if you tape the Jaws with Duct Tape so it does not damager the Shaft you will grip.

You would be rotating the Camshaft of the Fuel Injection Pump after you installed the Timing Locking Pin correctly. As you rotate the Fuel injection Pump Camshaft in the direction of normal rotation it will eventually push out the Plunger of the timing locking Pin and lock the IP Camshaft in place.
At that point you are ready to re-install the Fuel Injection Pump. (If you followed the directions in the pdf your Crankshaft was already previousl lined up on 15 degrees after top dead center of the compression stroke.)

For this sort of work the negative Battery Cable should have been disconnected from the Battery so there is no accidental cranking of the Engine. If you are using the Fuel Injection Timing Pin it is also a good idea to put a Sign on your Steering wheel so you are sure to remove it before cranking the Engine.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

"Timing Locking Pin is done at about 15 degrees after top dead center"? I'm just a tinkerer...how do you rotate the crank to 15 degrees ATDC? I know how to rotate the crank to 0deg TDC and verify cam time mark, but that's about the extent of my knowledge. How/where to you measure/read 15deg ATDC? Thanks!

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1993 300D 2.5T
1968 280SL - sold

well keep rotating untill 15 degrees after 0 your there!

OK. How do you measure 15 degrees? Is there a mark on the crank pulley similar 0 degree mark (and +/- degree marks) at 15 degrees?

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1993 300D 2.5T
1968 280SL - sold

This is NOT correct! The locking tool will not pop into place as the IP camshaft is rotated! If the IP is off the pump it would have its camshaft rotated until the blade shaped indicator is visible and centered in the opening and then the locking tool is installed so that the indicator blade fits directly into the slot on the tool's spring loaded head. Any attempt to rotate the IP with the tool either correctly in place or incorrectly in place is ill advised, the 603/602 FSM details the Injection Timing Device R&R in section 07.1.10 11- 240

If during your inspection of the timing device you have ascertained that the damage is confined to the timing device's rotating cam and you have another timing device in good condition and available, you should consider simply replacing the rotating cam only.

To do that you would basically go about it the same was replacing the timing device itself, the advantage is that you can mark the position of everything and restore it back into the same position without altering the timing conditions.

Turn the engine until the crank indicator reads 15 deg ATDC AND the IP indicator blade is visible and centered, install the locking tool.

Remove the valve cover, use a nylon tywrap the secure the timing chain into place on the sprocket. Using carb cleaner or brake cleaner spray the timing device sprocket and the chain on it, mark that position on the sprocket and the chain with quick drying paint marker. Counter hold the timing chain at the cam sprocket using a bar or large screw driver through the holes in the sprocket's center, remove the left hand threaded center bolt on the timing device, spray the area behind where the bolt head would be, mark the position of the timing device and the nose of the IP.

Remove the cam sproket bolt it is a regular righthand bolt, and the cam sprocket, let is hang down into the timing chain chase, remove the timing chain tensioner.

You will now have enough slack in the chain to use a self made thin sheet metal shim to slip between the timing device sprocket and the chain, that will allow you to pull the timing device forward of the IP nose and out of the engine.

Once out of the engine you can disassemble the timing device itself and swap your good rotating cam into place for the damaged one. Then you can reassemble everything in the reverse order lining up the paint markings on the timing device sprocket and the timing device thereby avoiding any timing alteration issue.

The cam sprocket is tywraped to the chain so that can't chang, the crankshaft should not have changed and the IP should not have changed.

Get all that together and rotate the crankshaft a couple times to make certain, then rotate it enough to position the rotating cam so that the vacumn pump's roller is in one of the cam's valleys and install the new vacumn pump and gasket.

There are marks on the harmonic balancer's outside edge, the best thing to do if you can, is start the car and with the engine running reach under the front on the engine with a wire brush and apply that to the rim of the rotating harmonic balancer, that will clean of any rust and/or grime. Then you can stop the engine and rotate it so that the markings are facing downwards, clean the area of the markings with acetone or paint thinner to completely degrease it, once that's done get some bright paint or her best nail polish, paint over the markings and then wipe the area off. That should leave residual paint down in the stamped indicator markings and it will make it 1000% easier to see the marks when you need to!

"IP indicator blade is visible and centered, install the locking tool" - Is this done by looking through where the plug was removed in step #9? If so, is it doable with the IP still in the car (having a hard time imagine getting my head down there...)?

"Once out of the engine you can disassemble the timing device itself and swap your good rotating cam into place for the damaged one. Then you can reassemble everything in the reverse order lining up the paint markings on the timing device sprocket and the timing device thereby avoiding any timing alteration issue." Looking at the timing device, it doesn't appear it is easily dissembled. The entire timing device to include the cam/lobe appears to be pressed fit (no bolted connections, etc.). How would I go about swapping the whole timing device?

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1993 300D 2.5T
1968 280SL - sold

If I am able to successfully lock the IP using the locking tool, can the damaged timing device simply just be removed and replaced? Does it make a difference the rotation of the timing device as it goes back on the IP splined cam as long as the IP cam doesn't rotate (after IP is locked)?

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1993 300D 2.5T
1968 280SL - sold

Yes, the IP bolt removed looking into the hole, most people use a mirror to get the best look.

I don't have a later model timing device at hand but the 86/87 vintage devices had two bolts from the rear of the device that held everything together.

If you need to swap the entire device the process is more involved in that the FSM describes removing the IP from the engine, then installing the timing device onto it and then installing both into place together. Of course that requires more work and parts removed to get the IP out.

The problem with just swapping timing devices from the front is there is a fixed relationship between the timing device's chain sprocket and the splined hub where the IP mates to it. When the IP/Timing device is installed as a unit the IP/Hub interface is fixed and locked by the IP locking tool, the chain is placed into position with no slack on the bottom between the timing device and the crank sprocket and once the timing device is in place the cam sprocket is returned to its fixed position the tensioner is used to remove/tighten up any slack in the chain run and the critical relationships between pistons, valves, and start of delivery is maintained.

When and if someone tried to swap timing devices it would be more difficult to while maintaining the correct timing device sprocket/timing chain position, to get the timing device hub/IP camshaft nose position correct, because of where it is and the lack of any reference marks at that interface. The spined hub/nose interface is numerous small splines so it is easy to get it off a spline or two in either direction. That is usually not much of a problem because the IP can be adjusted a bit in either direction. If you or the mechanic doing the job is comfortable potentially retiming the IP then that may be the way to go.

The rotating cam swap avoids the timing issue by using the same sp;ine/sprocket and establishing the reference marks prior to disassembling things, but if you can't swap the rotating cam it won't do you any good.

If you do end up removing the IP for any reason, get a new large O-ring that seals it to the block, often times once the original is disturbed it will leak quite a bit of oil and you'll eventually want to replace it necessitating complete removal of the IP again to accomplish that. With a new O-ring oil it and both the contact surfaces so that the rubber doesn't bind in place against the metal faces on either side of it when the pump is positioned and a leak develops as a result. If you have any of the gaskets on the IP itself leaking there will be no better time to renew those than when the IP is on the bench.

"If you need to swap the entire device the process is more involved in that the FSM describes removing the IP from the engine, then installing the timing device onto it and then installing both into place together. Of course that requires more work and parts removed to get the IP out". Dang, the project just got a lot more complicated and expensive....!!! If I have to remove the IP+, I think I just exceeded the value of the car in mechanic fees and it is time to put the moneypit out to pasture....dang x2. I will examine the replacement timing device this evening and determine if there is any way possible to only remove/replace the cam portion and not the entire timing device.

Looking at the MB repair manual procedure (07.1-8014, as attached in first thread)....paraphrased, Step #8 - remove timing device, #9 - unscrew plug, #10 - turn IP camshaft and lock, #11 install new timing device, #12 remove lock bolt, #13 put everything back together, #14 - "Test start of delivery with digital tester (07.1-112), set if necessary (07.1-117)" I am now to assume that step #14 basically means you have to re-time the IP no matter what if using this procedure, correct?

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1993 300D 2.5T
1968 280SL - sold

Well if you're paying someone to do the wrenching it can get cost prohibative pretty quickly unfortunately. I completely understand some folks need to go this route but on the other hand it's mainly just unbolting and removing parts and replacing them if someone has the time, place, inclination and a few hand tools usually.

Like I described because of the way things go together it is possible to get a situation where because of device tolerances and differences it is possible to have the timing change a bit when swapping parts out and in, so the FSM is pretty much always going to recommend testing as a means to verify the timing circumstances.

At least with this procedure as long as it is followed the potential timing issue is not one of possible mechanical interference but one of syncronicity beteen the mechaical components and the fueling start of delivery. Usually when the IP Timing device is removed or installed as a unit and assuming everything with the crank and camshaft is done properly the SOD will be quite close to its spec of 15 degrees ATDC, maybe a degree or two off. That is usually adjusted using the A-B Timing light tool because that is pretty easy and accurate, but using the IP lock tool as a means of verifing IP camshaft position can be virtually just as accurate, it just takes a bit more patience and effort to do so. Instead of using the light the correct timing is verified on the IP crankshaft, then if necessary the IP is loosened and adjusted to center the blade/tang in the opening where the locking tool needs to interface without any problem. It's in effect, a simpler but accurate mechanical indication of the IP being properly positioned, whereas the A-B Light uses essentially the same mechanical interface but translates that to an illuminated visual output that is slightly variable and much more easily observable.

But it is perfectly possible to get the things done with a correct end result is just takes a bit longer.

OK I will go with you on this one; but, I believe the in the Manual they did not want you Cranking the Engine with the Starter or running the Engine with the Timing/Locking Pin in place.

But, the below quote is how I used the Timing Locking Pin when I removed the Fuel Injection Pump. I don't recall making any attempt to determine what Stroke or degrees of timeing I was close to and of couse I gently turned it by hand.

Note that I installed the Timing Lockin Pin First.

"I used an IP Locking/Timing Tool for the first time and it is my fist time turning the Engine from the Crankshaft Bolt (except that you cannot watch the Degree Marks I had no problem fitting the Socket and Socket Wrench into the space available).

When you use the IP Locking/Timing Pin there is a slot that needs to be Horizontal after it is installed. On the outside of the Tool is a slot for Reference (See Pic).

I rotated the Crankshaft carefully in the direction of rotation until I felt resistance. I tried to rotate it backwards and also got resistance. I tried again in the direction of rotation and got resistance so I figured the IP was locked in position."

The above quote is from the first post of My Thread:
Fuel Injection Pump Removal with the Oil Filter still on 617.952

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84 300D, 82 Volvo 244Gl Diesel

The Degree Marks are on the Damper.
As you rotate the Engine and watch the Numbers pass by the Pointer the numbers start higher and get smaller (cound down) until you get to OT (top Dead Center); after that (after top dead center) the Numbers get larger as you rotate the Engine.

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84 300D, 82 Volvo 244Gl Diesel