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WANT '71 280SEL 03-09-2005 06:49 PM

it's running! AWAY!! TWICE!!
I finally got around to replacing the shut-off valve on my 300SDL. Well, I wasn't sure exactly what people meant by the rack so it all went back together and ran away from me. It was at WOT for about 30 seconds. I think I got the internal pieces messed up when I was trying to remove the bit nut that retains the stop lever mechanism. I got the "forK" piece on the wrong side of the rack (I guess that's what the piece is called). Like I said, it happened because I was fiddling around with the stop lever trying to get things apart. Mind you I was working on the stop lever itself because it was staying down even though the vacuum was released from the valve.

I sucked on the line which moved the lever so I thought I was good to go. When the car finally started it roared so loud I couldn't hear myself think! Then to top it off, I couldn't remember where I set the 14mm wrench which I just had in my hand! I then got a crescent wrench and had to minimize the size quite a bit because it was spread out from removing the ALDA.

Well, after it took off the first time I got it stopped. I then removed the shut-off valve again and made sure I had the nub inside the fork piece. Note, I still didn't really know how the internal piece was to be set up. So, I put it all back together and it ran away again! Well, I undid 4 of the 6 lines and the engine almost died. Then, as if God were cursing me, it came alive AGAIN louder than ever! I undid the last two lines and she finally died. I took everything apart again and did some thinking. Once I saw the piece at the bottom in the pump and figured it would have to move the other way I fixed it. It was actually quite a pain to get the lever on the other side of rack piece. Once I got it all back together my uncle came into the shop so I had him start it. Well, all was well then. The car smokes and shook like usual but other than the normal racket she's alright!

Never before have I been so scared while working on my car. My legs and arms were shaking!

Anyways, I definitely learned a lesson from this and I hope all you do as well. Luckily my car's alright. Oh yeah, so far I've gone 7k miles since my last change which was to Delvac 1 and I'm only down 1/2 quart! The only reason it's dropping that amount is because it's leaking and leaving spots just about everywhere its parked. I also need valve seals since it puts out some blue smoke when first started.



While I was at it I replaced the o-ring on the stop lever which was leaking just a tad. I did it since I had it all apart anyways. The o-ring is the same one as the one that comes with a new spin-on filter. You can order the set of o-rings (there are two that come with a new filter) seperately for a whopping $.54! Since you use the small one at the stop lever use the larger one to replace the one on the engine dipstick. The dipstick now has a nice "snug" to it like it should.


Brandon314159 03-10-2005 02:15 AM

Wow. :eek:
Way to not loose your cool though...atleast you did the right thing and started removing injector lines. Good thing the crecent was on hand.


Jimmy Joe 03-10-2005 02:30 AM

Man, that has got to be scary.
I feared that big time when I did mine.
Good for you for not loosing your motor.

Sucking on the vac line to the shutoff will make it function, even if it is out of the car!
What I found was that it is subtle to get it on the lever, but if you give it a tug before you tighten it down, you can fell resistance.
It feels like it is caught on something, which it is.

whunter 03-10-2005 03:51 AM

Added this thread link to

You saved the engine, but are you done shaking yet?
Good crises management training. :eek: :)

leathermang 03-10-2005 04:01 AM

"Never before have I been so scared while working on my car. My legs and arms were shaking!"

There ought to be a medal awarded for staying and saving the engine.... Because the rational thoughts (multiplied by the sound ) of one's own safety certainly dictate LEAVING THE AREA......
Some people have described trying to keep their head down behind the fender while feeling around with their hand in the engine compartment to find the shutoff lever.... which sounds very Monty Python to me....

Brandon314159 03-10-2005 04:03 AM


Originally Posted by leathermang
"Some people have described trying to keep their head down behind the fender while feeling around with their hand in the engine compartment to find the shutoff lever.... which sounds very Monty Python to me....

I guess some people just aren't used to the sound of their diesel at WOT for extended periods of time...

...not that I am one of them ;) :D

leathermang 03-10-2005 04:17 AM

My 240 had low compression on one cylinder and high oil usage on a low mileage rebuild... TCane and I had tried to figure out why and all we could think to try before taking it apart was to ' rebreak in' the engine...
This consisted of all sorts of rpm contortions .... and for the record I have no hood pad on my car.... I wound this engine so high so many times during an hour of 'break in' that I thought my blood pressure was going to burst MY HEAD ...
If anyone else had witnessed it they would have sworn I was trying to blow up the engine for insurance purposes or something....

d.delano 03-10-2005 10:20 AM

I'd have to scrape out my shorts after that for sure:)

boneheaddoctor 03-10-2005 10:28 AM

Having blown several engines myself I have yet to see scrapnel flying when one goes.......

Blew a Lancia Scorpion engine in Zero Degree about 5,000 rpm when it let loose.......You can't inagine the steam cloud generated when a rod goes through a water jacket and through the block with a hot motor on a day that cold. You can't see 2 feet in front of you till it clears. Only engine that didn't contain all the parts inside itself.

WANT '71 280SEL 03-10-2005 10:40 AM

I wasn't afraid of shrapnel per say but I feared for the engine. That comes up quick to WOT! At first it choked for a couple seconds then shot up, WAY WAY UP! So, a second after the car started I thought I was good to go, boy was I surprised! That fuel sure does make a mess though. I brought the extinuished over after the first run-away incase fuel met the manifold and ignited. I was fortunate however to not have THAT happen. I was afraid that after I got it back together correctly that I'd hear some funny noises, but all seems well. I may have taken a 100k off the total life of the engine, but hey, engines always outlast the body right?


WANT '71 280SEL 03-10-2005 10:51 AM

I thought I read somewhere here that the 603's aren't as likely to run away. I guess they can but you just have to let things come apart, no fiddle and jiggle.


Rahulio1989300E 03-10-2005 04:02 PM

How high did the RPMs get?

It sounds like you were above redline?

What were you trying to fix?

I am confooosed.. :confused:

leathermang 03-10-2005 04:54 PM

If that question was for me... I don't have a tach... but about as far over the max dots on the speedo for all the gears as it would turn... We thought some rings might be stuck. I was using the engine as a brake going down " hills " as soon as I got wound up...

WANT '71 280SEL 03-10-2005 08:50 PM

rhu, I'm sure it went up to the mechanical governor which is around 5150 rpms. Either way, that's not good but my uncle said that 25-30 seconds isn't THAT bad especially considering these are robust engines. Like I said, the car doesn't smoke any more than it used to and the power, etc. is all still there. I don't think it damaged the engine at all to be honest.


The last thing on my mind when it was running away was to look at the tach. As soon as the rpms started climbing I was out of that car so fast...

Hatterasguy 03-10-2005 10:15 PM

You didn't hurt anything. Dslbnz has a video of his SDL at 5,200 rpm; he just put his foot down and held it their for a few minutes.

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