Why cant it just be a vacum line - PeachParts Mercedes-Benz Forum

TX76513 · #1 03-31-2004, 02:03 PM

Guess I was going along to long without having to replace something - went to turn the key off and the engine didn't stop.
Armed with my Miti-Vac it was quick to determine the shut off valve on the IP is leaking

. Looking at the valve it seems cut and dry DIY....until I started to read some of the threads

This will be a Friday project. There is a lot of information about this procedure in the forum and I do understand the cautions and will have 17mm wrench, cutters, rabbit's foot, 2 black candles lit, watch for tab alignment, pull up, etc. Most of the information written is for 123's. Before I start this does anybody have anything specific I should know about 126's?

kmaysob · #2 03-31-2004, 04:08 PM

first try unhooking the shutoff valve lines and apllying vacuum directly to the shutoff valve with your miti-vac. if the engine shuts off you have a leak probly at the ignition switch. thats what was wrong with mine.

TX76513 · #3 03-31-2004, 05:51 PM

That's the procedure I used - and same conclusion

compress ignite · #4 03-31-2004, 06:47 PM

Are we talking about 86 300SDL?
(May not be relevent on your model)

I.P. shutoff (vaccum) failed on my '84 300SD (before the
Gods of Diesel let me know about it) the vaccum pulled
oil (sump) up into the ignition switch.As if this wasn't
enough of a penalty,I also found oil (sump) in the A.C.
controller!

Changing the shutoff is no big deal ...Just be sure to
put vaccum to the new shutoff when installed and positively verify that the fuel linkage (RED OFF) moves.
Otherwise DON"T START ENGINE.

psfred · #5 03-31-2004, 08:07 PM

The SDL has the 603 engine, so the shutoff replacement is a bit different.

You must remove the ALDA to get one of the retainer screws out (bad design).

Get a new gasket for the servo, too.

This one is fairly simple, and if the stop lever moves with vac, it won't run away, but keep the wrench handy anyway.

NOTE: Injector Cap nuts are 14mm, not 17 mm on this engine !!

Do a search, the procedure has been covered several times. Other than taking the ALDA off, it's easier to change the servo on the 603 than the 617.

Peter

Stevo · #6 03-31-2004, 08:27 PM

TX76513

If you pull a vacuum on the switch and it shuts the engine off it can still be bad. Mine works but it leaks vacuum and I am going to replace it tomorrow. I keep a pair if bolt cutters handy to nip the high pressure lines in a run away situation.

#7 04-01-2004, 11:57 AM

Add this to my paranoia list!

Stevo · #8 04-01-2004, 06:25 PM

"hotskillet Add this to my paranoia list! "

I have bolt cutters in my shop to use for lots of things, its just now they live in a handy place in relation to where I would be starting a car. I have extra IP lines so cutting them would not be a big deal and I think one could do that about the quickest.

I have seen tugs with a "reach rod" going down to shut of the engine off case nobody wonted to go down there with a runaway engine. Not me, somebodys gota drive

Steve

TX76513 · #9 04-02-2004, 08:48 AM

Part came in so the task was completed last night. On the PIA scale probably is a 7 on this engine, lot's of things to move to get access. Installation is not tough - just a little high on the nerve scale. Took me about 2.5 hrs - don't know if that's good or bad.
Had #1 son man the ignition while I monitored the engine bay.
Yes he gave it a blast of acceleration when he started it ---then laughed.

More grey hairs

Life is good again the engine stops with key

coachgeo · #10 04-02-2004, 09:29 AM

Quote:

Originally posted by TX76513
...Had #1 son man the ignition while I monitored the engine bay. Yes he gave it a blast of acceleration when he started it ---then laughed. More grey hairs ...

So did you demote him to #2 son?

TX76513 · #11 04-02-2004, 10:09 AM

Quote:

Originally posted by coachgeo
So did you demote him to #2 son?

Better said - #2 Son almost became #1 Son.

I had seen no humor in that "April Fools" joke - since we had a discussion on "what might happen" and he had to sense my concern

psfred · #12 04-02-2004, 07:35 PM

Kids are payback for all the horrible things you did when you were young!

Peter

TX76513 · #13 04-04-2004, 07:47 PM

I know:p