Cam for vacuum pump destroyed - PeachParts Mercedes-Benz Forum

ricali · #1 05-05-2003, 07:24 PM

My vacuum pump failed and destroyed the cam on the gear that drives the pump. What a mess pieces all over. My question is the cam part of the gear? Is the vacuum pump gear driven by the timing chain? If its all bad news will I have to tear down the whole engine to get at the gear chain and followers? Oh yes 95 E300 6 cylinder non turbo.
Thanks for any help

psfred · #2 05-05-2003, 11:21 PM

The cam is part of the injection timer, so you will need a new timer. PITA to replace, requires two special tools to lock the IP and hold the chain, not possible to make yourself.

Be glad, though, that nothing got into the chain. A new centrifugal timer is MUCH cheaper than the result of a broken chain!

Peter

ricali · #3 05-06-2003, 04:57 PM

psfred

Thanks for reply. I bought all the parts today for Phil at fast lane.

Got a major mess on my hands. I am going to replace the chain , rails, tensioner timing gear and vacuum pump.
Started stripping it down, but am not sure if I need to remove raidatorfor theAC? Also don't have a clue where to start when replacing the gear and chain. Don't have a good grasp on how the gear is connected to the IP and how to align everything for timing. Any advice anyone could give would be very appreciated

Thanks

psfred · #4 05-07-2003, 11:51 PM

YOU MUST HAVE THE TOOL TO LOCK THE INJECTION PUMP!!!!!!

There is a special tool for this, not expensive, but you will play merry hell getting the pump timed again with out it, nothing holds the pump in time (it's not like the older ones, where the oil pump drive hold the timer shaft in place).

You will also need the tool to hold the cam gear in place while you take the timer off -- you can fabricate this one, anything that clamps the chain to the cam sprocket and also hold the two to the head will work.

You will need to replace the timer first, then the chain and guides -- guides are "pull the bolt pin then drive new one in" or variations. Chain will require that you grind the swages off the pins on one link, then press the link apart, attach and new chain to one end of the old one, then rotate engine by hand to drag the new chain around -- keep tension on both ends!. when the new chain is installed, disconnect from old chain and swage a new link in place. You really need the tool for that, too, its available for rent. I borrow one.

If you lock the IP correctly, the timer is a simple unbolt, remove timer by lifting chainoff sprocket, install new timer by lifting chain, bolt on. IP timing should not change.

If you don't have the IP locked, it's going to be nasty.

Peter

ricali · #5 05-09-2003, 06:11 PM

psfed
Thanks for your reply. That was the exact info. I was looking for.
I bought the tool from Mercedes for $33. I have some small clamps to hold the chain to the sprocket. I'm just worried about getting the gear back under the chain. It looks like the gear has to come thru the vacuum pump hole! Also will there be any problem of the chain slipping of the crankshaft when I try to put in the new gear??
Thanks again for your help

psfred · #6 05-09-2003, 11:10 PM

If it's like the 617 engine, what you do is lock the IP, then compress the tensioner so that you have some slack in the chain. Back the cam up to transfer the slack to the timer side, then use a pair of small screwdrivers or a thin bit of sheet metal to lift the chain off the timer and pull it out (unbolted first, mark the timer and chain so the go back in the same place!).

Not as hard as it sounds, we put the chain in my brothers and then put the timer in. Cheating of course, since the engine was on a stand and not in the car!

Peter

ricali · #7 05-11-2003, 03:27 PM

psfred

thanks for your help. I got it all back together on saturday. What a job. It started up and runs well EXCEPT the engine is noticalby louder than before. I suspect it off timing. I don't have a clue how to adjust it. Probably will have to take it to the dealer to adjust the timing. Didn't think it would have been off as I was very careful putting the gear back in.
Found lots of carbon in the intake both wet and dry. One of the plastic emmission hoses was not hooked up and it may been sucking up some oil ladened air.
On the plus side all the vacuum operated things, like the brakes now work excellent.

psfred · #8 05-11-2003, 10:20 PM

The 603 is farily quiet, but still a diesel. You may just be hearing normal diesel noise, if the chain was worn, the timing (valve and injection ) was late. Late timing makes the engine quieter.

Unless you have smoke at low speeds or it is VERY noisy (like a Cummins), it's OK. If you do decided to have the timing checked, there is one way to do it at home. Otherwise it requires "special tools"

To check, lock the injection pump with the locking tool. Timing must be 15 degrees after top dead center (this in not the actual injection time, just the point in rotation where the pump lock engages). Be very carefull, as it possible to damage the pump by screwing the tool in when it is not at the correct rotational position. You can also set the engine to 15 degrees ATDC, then move the pump with the little captive nut (you must loosen the hold down bolts from the front) until the lock engages.

The "special tool" is a Hall Effect pickup that uses the lug the locking tool engages to set the timing. The fancy version will actually give you dynamic timing, since it also has a crank position sensor.

Synthetic oil will reduce the carbon buildup in the manifold -- it won't coke so much front the hot exhaust gases from the EGR. Or you could just disoconnect the EGR like I did.

Peter

md21722 · #9 05-12-2003, 11:27 AM

psfred,

From his first post he has a 1995 E300 (OM606, 24 valve, non-turbo). I am not sure if 15 degrees is correct timing for this engine.

Brian

psfred · #10 05-12-2003, 09:21 PM

Brian:

I'll have to check, the only thing different between the engines is the head and injector location.

Peter

ricali · #11 05-14-2003, 02:00 PM

Thanks Again

I set the crankshaft pulley to 15 degree and the pump was locked. The camshaft was also on the dots. After starting it did smoke some. There is an 8 mm hex screw on the top of the pump towards the radiator, I turn this screw counterclockwise as looking down at it about 3 turns. The engine smoothed out and runs great with no smoke and starts very well cold or hot. What bothers me is that it does have more actual diesel noise then before. I realize that late timing will make it quiter, if this was the case it must have been like that for the past 50k. I dropped it off a my local dealer to have the timing set. I'm one of those worry warts.
I always use synthetic oils.
The dealer told me coking in the intake is very common and not to worry about it.
While everything cocerning vacuum has never worked so well, the tranny now needs to be adjusted os I'm letting the dealer set it all up. Hey at 188k it's time for a little tune

But never again will I ignore a warning sign like low vacuum.
In hind site I probably should have bought the tool to set timing.

gsxr · #12 05-14-2003, 04:17 PM

The dealer is right, intake coking is normal and don't worry about it. You can set the timing yourself with the lock tool, it wasn't designed for that, but it can be done. I like to set the timing slightly advanced (about 14 ATDC) as I notice a slight increase in MPG. The "proper" RIV tool (A-B light box) costs about $250 from the cheapest source I know - probably not something you want to buy unless you'll use it more than once.

Oh, and the 603 and 606 engines share almost nothing AFAIK; they are TOTALLY different! Definitely try killing the EGR if you can. The 602 turbo engines were "smart" enough to know if you did this and made the computer go nuts. I don't know if the 606 will do this or not, it may be OK since there's no turbo involved.

Regards,

ricali · #13 05-14-2003, 07:27 PM

I probably should have bought the tool and then i could have put it in my tool box with my flat head Ford valve tool.

I'm sure the timing was on but, i need to drive it to Pa. and back every other week about 1K and don't want a problem on the road.
I still don't know if the screw on top of the pump is the timing adjustment

The last time I had a problem i drove it 1k without shutting it off.
Not good for the kidneys.
Thanks for everyones help. I never would have tackled the job without it.

ricali · #14 05-14-2003, 07:30 PM

BTW how do I disconnect the EGR system??

psfred · #15 05-15-2003, 09:24 PM

Just pull and plug the vac line to the EGR valve to disable it. Or make a plate and put under it if you want.

Peter