602 Problems New Info HELP!! - PeachParts Mercedes-Benz Forum

350SL4spd · #1 08-31-2004, 04:18 PM

Nemesis: Taupe 1991 300D 2.5
I have been reading up and still have no answers (well, I have learned some pretty cool stuff, but nothing that helps at the moment). I have pulled the intake pipe that comes over the top of the engine to make it a natually asperated diesel and eliminate any and all issues w/ EGR/intake flap/boost control/etc. I have also unhooked the ALDA so it is only getting atmospheric pressure (not that it should matter w/ no boost in the intake). Still having the following prob:
Vehicle refuses to go over 2k rpms under load. If I unhook the sensor connectors (2) on the Injection Pump it will go over 2k and even shift up, but it takes me almost 2/3 of a mile to get over 30mph.
My "friend" whom I was doing a "favor" for by working on his car is now threatening legal action if he doesn't get it back soon and I have run out of $ to fight this thing (and options as to what could be wrong). Assuming that the computer has no control over the IP (as I have read) why the heck does it not go over 2k rpms with it hooked up?!? And if tit's not the computer, then what? The control rod in the IP is sticking? What else could be wrong??
Some one suggested checking the screen in the fuel tank, but I don't see how anything could be clogging that up as it has only been sitting a couple months during this work. Right??
Please; any ideas of suggestions would rock. The last thing I want to do (or can afford) is to have it flatbedded 70mi to the dealership so they can read the codes!! (Can I do that w/ a muti-meter like on a gasser?!?! HOW??)
Thanks all for your patience and assistance!
-Matt-

compress ignite · #2 08-31-2004, 07:30 PM

Try re-posting on "Tech" forum.

(If I were you , I'd replace Everything to Factory....and then diagnose)

TimFreeh · #3 08-31-2004, 09:24 PM

As I recall this was a junkyard engine that replaced an engine that had lost a chain on the oil pump drive - is there any warranty on the junkyard engine?

I'd start with the easy things 1) is the throttle linkage control moving thru its entire range of motion? 2) Are you sure you hooked up the fuel feed and return lines correcty? Restricted fuel feed would be consistent with your symptoms.

If these check out I'd check 1) cam timing 2) IP timing and 3) IP internals.

350SL4spd · #4 08-31-2004, 09:45 PM

Tim: The junkyard engine had 70psi per cyl and was returned (I ate the labor)

. The original was rebuilt after throwing the oil chain, only the rod bearings were seized, but we put in new rings too. Throttle linkage has been checked and rechecked and is free and clear. The fuel lines are where they belong, but I am going to go over them a third time just because I want that to be the prob. And yes, it does act like resticted fuel, my only fear is that it is a failure inside the IP. Cam timing has been double checked and is right on. Start of delivery (IP timing) has been set by the drip method, which I hoped would be close enough to drive it somewhere to get it done electronically. Maybe it's still too far off??? I am living a nightmare....
Any other advice??? I guess I might have to pull the IP and get it checked out next, huh?
-M-

TimFreeh · #5 08-31-2004, 09:57 PM

Can you use the drip method to time an OM602?

What procedure did you follow to set the timing?

psfred · #6 09-01-2004, 12:24 AM

The 60x engines can be set with the drip method, but if you use the listed timing it will be WAY off (book says 15 ATDC!). That spec is for the tools (including the dymanic one). If you didn't use 24 BTDC as the timing spec for the drip method, retime it, it's way off (should be smoking pretty bad, too). You won't get boost with late timing.

Unless you took the IP apart, there is nothing wrong with it. Can take a while to purge the air out since there isn't a hand pump, but it should be fine. Note that setting timing and the injection timer behind the vac pump is a bit tricky.

Check for leaking pressure valve seals if you replaced the o-rings on the pressure valves, they are prone to leaking. You will get plenty of fuel when you crack the injection lines, but none actually delivered under pressure -- rough idle and hard knock.

The EGR MUST be working on later models or the computer shuts the boost off, don't know if this applies to yours. That means clean the valve and make sure the vac system is working properly. Very hard to work around reliably.

Peter

gsxr · #7 09-01-2004, 01:02 AM

It wouldn't be the first time someone installed the IP and got it 180 degrees out of time with the cam... I think I said this in the last thread? BTW, starting a whole new thread for the same problem can be confusing... I would have missed this if I hadn't happened to be surfing the forum tonight. (I was subscribed to the previous thread on the same topic.

)

And yes, it needs to be set at 24 BTDC with the 'wet' methods. If set to 15 ATDC via drip, it would run horribly, if at all...

TimFreeh · #8 09-01-2004, 09:21 AM

I did not know the drip method was valid for the OM60X - learn something new everyday.

Since he may be re-visiting the timing lets also review a couple of often forgotten drip timing gotcha's. I'm assuming the procedure for the 60X is the
same as the 61X.

1) Don't forget to remove the delivery check valve on the number one cylinder

2) Don't forget to set the throttle linkage wide open before you start the delivery test.

3) Don't forget to have plenty of rags around....

It seems like you would also have to wire up a manual fuel feed pump since the OM60X engines don't have hand powered fuel primer pumps.

Please tell us how you mounted the pump when the engine was re-assembled and the specifics of the procedure you used to time it via the drip method.

TIm

350SL4spd · #9 09-01-2004, 12:09 PM

I am on my way out to re-time the IP...I have to check my notes when I get out there to see where (btdc/atdc) I timed it originally

...
The pump never came off when I rebuilt the motor, so I had hoped that it would be close.
gsxr: Sorry to thread jump... The timimg was off before, but I fixed that. The cam was actually off by 180*. Turns out that the crank turns twice for every one turn of the cam

so I flipped the cam...
My fears for the IP are that when the engine ran out of oil, the IP was starved for oil and the control rod (or something) is sticking now.
What really bakes my muffin is the fact that pulling the sensor/idle control wires off I see improvement

Will try to re-time...if that doesn't fix it I guess I'll have to pull the pump and get it looked at.....

Thanks guys!
-M-