PeachParts Mercedes-Benz Forum

PeachParts Mercedes-Benz Forum (http://www.peachparts.com/shopforum/)
-   Diesel Discussion (http://www.peachparts.com/shopforum/diesel-discussion/)
-   -   '85 300SD CRAWLS on initial take-off (http://www.peachparts.com/shopforum/diesel-discussion/103106-85-300sd-crawls-initial-take-off.html)

1stimer 09-08-2004 11:42 PM

Sounds like the same problem I had.......EGR was not fully closing. Please check that if your's has one. I've been out of the loop for a while (many trouble free miles (fingers crossed), so I hope you're car has one.

whunter 09-09-2004 12:34 AM

Gadzooks
 
Quote:

Originally Posted by 1stimer
Sounds like the same problem I had.......EGR was not fully closing. Please check that if your's has one. I've been out of the loop for a while (many trouble free miles (fingers crossed), so I hope you're car has one.

Yours was not blocked off? :SHOCK:
You make a very good point, it is possible. :(
The EGR is a breakdown waiting to happen. :eek:

Fuzzball 09-09-2004 02:34 PM

Quote:

Originally Posted by whunter

Too the main event!
STOP:
Do not mess with the ALDA yet.
Try cleaning the ALDA air feed banjo and line first.

Whunter,

I have a brand new line from the Banjo bolt to the Crossover on the firewall. The line from the Crossover to the ALDA looks clean.

The top of the Crossover valve has some kind of rubber goo on it. I don't want to peal it off, just in case it's covering a hole or something.

Would it be a good test to run direct from the Intake manifold to the ALDA to see how the performance is affected?

I just don't want to do anything that will mess up the car.

Fuzzball 09-09-2004 02:37 PM

Quote:

Originally Posted by whunter
Yours was not blocked off? :SHOCK:
You make a very good point, it is possible. :(
The EGR is a breakdown waiting to happen. :eek:


So, would it be a good idea, performance wise and for off road use only ;) ;) ;) to block off the EGR tube? At least as a test...say using some heavy aluminum plating?

gsxr 09-09-2004 02:41 PM

Quote:

Originally Posted by Fuzzball
Whunter,

The top of the Crossover valve has some kind of rubber goo on it. I don't want to peal it off, just in case it's covering a hole or something. Would it be a good test to run direct from the Intake manifold to the ALDA to see how the performance is affected?

1) The valve has three ports. The top one is normally capped off - you can leave it alone.

2) Yes, you can temporarily bypass the valve and see if there's any change. Also you want to try to blow through the valve - if you can't, it's plugged, and needs to be cleaned or replaced!


:cool:

gsxr 09-09-2004 02:42 PM

Quote:

Originally Posted by Fuzzball
So, would it be a good idea, performance wise and for off road use only ;) ;) ;) to block off the EGR tube? At least as a test...say using some heavy aluminum plating?

That's a roger, Roger. I did this on my 603's and my 617 as well. Photos of before & after are at this URL:

http://www.meimann.com/images/mercedes/OM603_intake/



Here's what a 603 looks like with the, uh, 'heavy aluminum plating' installed:

http://www.meimann.com/images/merced...EGR_after2.jpg

whunter 09-09-2004 06:43 PM

the top is a vent cap!!!!!!!
 
1 Attachment(s)
Quote:

Originally Posted by Fuzzball
Whunter,
I have a brand new line from the Banjo bolt to the Crossover on the firewall. The line from the Crossover to the ALDA looks clean.
The top of the Crossover valve has some kind of rubber goo on it. I don't want to peal it off, just in case it's covering a hole or something.
Would it be a good test to run direct from the Intake manifold to the ALDA to see how the performance is affected?
I just don't want to do anything that will mess up the car.

:eek: If someone put goop in it, the crossover valve can NOT work. :eek:
Picture attached showing cap.

gsxr 09-09-2004 06:50 PM

Minor correction. The cap can be sealed, or not - it doesn't matter. When properly connected (manifold to bottom port, ALDA to center, cap on top port), and the overboost switch triggers, the center port switches from default position (connected to the bottom, manifold pressure) to the top position (capped off). My 617 refuses to build over 15psi even with the wastegate disabled, so I bypassed my valve permanently (although I don't recommend this unless you understand the risks involved.)

;)

engatwork 09-09-2004 07:11 PM

I recommend using caution bypassing the over pressure switch. I had an issue with my '85 300D where right before it shifted and at high speed runs it would "cut out". I did some troubleshooting and found the hose that signals the wastegate had a hole in it and it was pressurizing enough to trip the over pressure switch. I can see where some engine damage could be done if the hose at the wastegate leaks badly enough to prevent it from opening up.

whunter 09-09-2004 07:13 PM

My mistake
 
Quote:

Originally Posted by gsxr
Minor correction. The cap can be sealed, or not - it doesn't matter. When properly connected (manifold to bottom port, ALDA to center, cap on top port), and the overboost switch triggers, the center port switches from default position (connected to the bottom, manifold pressure) to the top position (capped off). My 617 refuses to build over 15psi even with the wastegate disabled, so I bypassed my valve permanently (although I don't recommend this unless you understand the risks involved.) ;)

Thank you for the correction. :)

oilslick 09-10-2004 04:36 PM

Back to the subject...
 
Since I started this thread I figured that I would nudge it back into the direction it was intended to go before it flew out one of those open "doors" :p .

I tweaked the ALDA and it did help. The problem is really a morning problem so I will have to see if the ALDA tweak really helps the real problem in the morning when I start out of the drive.

Thanks for the input. BTW, would any of you be interested in a 1984 380SEL? It is complete but has no title. My friend wants $300 for it. It supposedly has a bad fuel distributor.

Hey, I hijacked my own thread! :confused: :p :rolleyes:

Kevin

Carrameow 09-10-2004 04:47 PM

Please see my post about Fuel Pump replacement/rebuilding
 
I was in this identical position once and the Forum convinced me my engine was dead. The good thing was I got a new 87 300D out of it, because thats what I bought instead of a new engine!
Later on, I found out that the Fuel Pump was toast. They do that sometimes because of incosiistent fuel quality and low sulfur in today's modern diesel....3 ou of 5 barrels were dead, the ALDA had a BAD leak, other parst were dead
...

Eskimo 09-10-2004 05:31 PM

Quote:

Originally Posted by engatwork
I recommend using caution bypassing the over pressure switch. I had an issue with my '85 300D where right before it shifted and at high speed runs it would "cut out".

Forgive me for a minor hijack of the thread, Jim, but was this on the black '85 I'm driving? I'm a little embarassed, but for the life of me, I've been unable to locate the "overboost protection" valve on this car. I wasn't troubleshooting anything, just trying to get acquainted with everything under the hood. Am I missing something obvious?


-- eskimo


All times are GMT -4. The time now is 11:08 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website