Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help




Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #16  
Old 07-13-2006, 07:30 AM
deferr's Avatar
Want a ponton!
 
Join Date: May 2004
Location: Fort Wayne, IN 46835
Posts: 167
Quote:
Originally Posted by arcticathlon
i would say that your tank screen is plugged and needs to be cleaned. the fuel looked dark almost blue, and that is what mine looked like when i took it out and had it steamcleaned. it was nasty. but taht much air is not right.
The fuel is a little dark in the filter. I am working on the car on Friday so I will check the tank strainer then.

Quote:
Originally Posted by JimmyL
Would a leaky primer pump cause an anomoly like that in the prefilter
Anybody have an answer as to this?



Quote:
Originally Posted by Boardmonger
Nice videos, maybe other memebers should do them as well. I can do a few this weekend if people would like.

Today I gave my car a nice long glow and flicked the key and it started. I mean flick, almost like a snap. I was pretty impressed
I will have to check the glow plugs tonight and see if any are out.

I am more than willing to do some more videos as well.
__________________
'78 300D 85,000 original miles drive her daily
Reply With Quote
  #17  
Old 07-13-2006, 09:40 AM
resago's Avatar
Registered User
 
Join Date: Jul 2006
Posts: 79
need to remove a variable in the tea kettle test. block the vent. the condition of the vent tube and everything down range will make it different on everyones engine.

-just a suggestion
__________________
'82 Euro MB 300 D Turbo Silver/Blue - Fixed
Adding W115 Intake and Intercooler

1986 Chevy Camaro Cp 400HP For Sale
Engineer
Tuscaloosa, AL
Reply With Quote
  #18  
Old 07-13-2006, 09:58 AM
Banned
 
Join Date: May 2002
Location: Blue Point, NY
Posts: 25,396
Quote:
Originally Posted by Jeremy5848

I would like someone who understands these engines to explain to me why they stall when you plug the breather. I understand that pressure builds up in the crankcase but it would not seem to be very much pressure if you can hold your thumb over the vent. What exactly causes the engine to stall?
The shutoff diaphragm on the IP is vented to the crankcase from the inside. When pressure builds in the crankcase, the shutoff diaphragm moves in similar fashion to applying vacuum to the outside and fully closes the rack.

BTW, this test is not recommended due to the rather high crankcase pressure...........and the possibility of blowing out the crankshaft seals.

Furthermore, why concern yourself with blowby? You cannot do anything to improve it without spending thousands of dollars and it has no real impact on the day to day operation of the engine.
Reply With Quote
  #19  
Old 07-13-2006, 10:32 PM
Diesel Giant's Avatar
Registered User
 
Join Date: Oct 2004
Location: Loganville/Atlanta
Posts: 2,156
Quote:
Originally Posted by Brian Carlton
Furthermore, why concern yourself with blowby? You cannot do anything to improve it without spending thousands of dollars and it has no real impact on the day to day operation of the engine.
That is the darn truth!

I have 2 MB's that have almost no blow by, but on a 616/617 engine that is 20 plus years old, that is really rare.
__________________
1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
Mercedes How-To and Repair Pictorials
I love the smell of diesel smoke in my hair
Reply With Quote
  #20  
Old 07-13-2006, 10:40 PM
deferr's Avatar
Want a ponton!
 
Join Date: May 2004
Location: Fort Wayne, IN 46835
Posts: 167
Excellent point about the blowby I suppose. I will keep everyone updated about the tank screener. I will be testing this tomorrow.
__________________
'78 300D 85,000 original miles drive her daily
Reply With Quote
  #21  
Old 07-14-2006, 11:26 AM
winmutt's Avatar
85 300D 4spd+tow+h4
 
Join Date: Apr 2006
Location: Atl Gawga
Posts: 9,322
Quote:
Originally Posted by deferr
Yes it normally takes that long to start. I thought that was a short start time. When I got the car (2 years ago) it took considerably more than that. Is this a relatively small amount of blow-by?

I also have another video that I was going to post separately but it might be applicable. I'm suspicious of a clogged tank screen. If you watch this next video you can see that when I start the car the fuel in the prefilter seems to be restricted, or sucking air. The hoses are tight at least where they hook to the filter and the steel line.

Is my blow by acceptable?

Anybody have any comments about this next fuel filter video?


Prefilter Video
That bubble is to big. Are small air bubbles coming from the tank? Time to replace the hoses.
__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1987 300D Sturmmachine
1991 300D Nearly Perfect
1994 E320 Cabriolet
1995 E320 Touring
2001 Eurovan FOR SALE
1985 300D car, sold and missed.
OBK #42
Reply With Quote
  #22  
Old 07-20-2006, 02:01 PM
Jeremy5848's Avatar
Registered Biodiesel User
 
Join Date: Mar 2006
Location: Sonoma Wine Country
Posts: 8,393
Quote:
Originally Posted by Brian Carlton
The shutoff diaphragm on the IP is vented to the crankcase from the inside. When pressure builds in the crankcase, the shutoff diaphragm moves in similar fashion to applying vacuum to the outside and fully closes the rack.
Thanks, Brian. Is that venting deliberate on the part of M-B's designers? (I need to learn more about diesel injection pumps.)

I would not think that the pressure would be high enough to blow out a seal. Nonetheless, I will be careful. And yes, you are correct that blowby can't be fixed by buying (as Click and Clack are fond of saying) a can of something that says "Miracle" on the label.

Anyway, my engine doesn't use any oil between changes and starts easily so I won't worry.

Jeremy
__________________

"Buster" in the '95

Our all-biodiesel family
1995 E300D (W124) . .239,000 miles My car
1996 E300D (W210) . .313,000 miles Wife's car
Santa Rosa population 170,685 (2012)
Total. . . . . . . . . . . . 722,685
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970
Reply With Quote
  #23  
Old 07-20-2006, 02:51 PM
Banned
 
Join Date: May 2002
Location: Blue Point, NY
Posts: 25,396
Quote:
Originally Posted by Jeremy5848
Thanks, Brian. Is that venting deliberate on the part of M-B's designers? (I need to learn more about diesel injection pumps.)

I would not think that the pressure would be high enough to blow out a seal. Nonetheless, I will be careful. And yes, you are correct that blowby can't be fixed by buying (as Click and Clack are fond of saying) a can of something that says "Miracle" on the label.

Anyway, my engine doesn't use any oil between changes and starts easily so I won't worry.

Jeremy
Can't say the intentions of the Germans.........they're a pretty secretive bunch.

I wouldn't want to lay any odds on that. You might be correct........but........what if you're not?

Too much time spent discussing blowby. It provides some indication of the condition of the rings and helps to make a decision on keeping the vehicle for the duration. But, in the short term, there's nothing you can do to improve the situation............
Reply With Quote
  #24  
Old 07-20-2006, 03:16 PM
winmutt's Avatar
85 300D 4spd+tow+h4
 
Join Date: Apr 2006
Location: Atl Gawga
Posts: 9,322
DG: thanks for the useful video, cant wait to go home and check it.
__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1987 300D Sturmmachine
1991 300D Nearly Perfect
1994 E320 Cabriolet
1995 E320 Touring
2001 Eurovan FOR SALE
1985 300D car, sold and missed.
OBK #42
Reply With Quote
  #25  
Old 07-21-2006, 08:45 AM
no-blue-screen's Avatar
Registered User
 
Join Date: Jul 2006
Location: Laurel, MD
Posts: 103
On the blow-by test:

I notice some have those cheap plastic oil fill caps and some of us have the OEM heavier metal ones. I would think the plastic caps would bounce around a lot more since they are much lighter than the metal ones. I happen to have both types and I didn't like the plastic one because it still leaked. I purchased new gaskets for the metal one and adjusted it so that it fits tightly.

With this test.....is it required to use the plastic cap? I just ask because the results with the two different caps would surely be different.
__________________
2008 Jeep Grand Cherokee 3.0 CRD (OM642)
Reply With Quote
  #26  
Old 07-21-2006, 09:20 AM
Registered User
 
Join Date: Jan 2002
Posts: 18,353
Compared to other 617's that I've seen that started and ran fine, you have no blowby. I looked at one that chugged like a steam locomotive out the oil fill hole when warm but had no detectable problems. There is a device for measuring blowby but I've never seen one. I think the smother test is largely irrelevant because the time it takes to shut down the engine is entirely dependent on the quality of the seals in the engine. (not to mention the altitude at which you perform the test) A slight seal leak somewhere, even in the oil fill cap, would increase the shut down time.
Put some diesel in a soda bottle and run a fuel line from it directly to your primary fuel filter and see if this shortens cranking time. If so, it would show you have a problem between the tank and the filter.
__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13
Reply With Quote
  #27  
Old 07-21-2006, 11:00 AM
Jeremy5848's Avatar
Registered Biodiesel User
 
Join Date: Mar 2006
Location: Sonoma Wine Country
Posts: 8,393
Teakettle test

I loosened my oil filler cap but it didn't rattle around at all. Didn't even move. Engine was hot, cap is the OEM heavy metal one. If I plugged the breather hose, there might be enough pressure to make it bounce a little, I'll have to try that.
__________________

"Buster" in the '95

Our all-biodiesel family
1995 E300D (W124) . .239,000 miles My car
1996 E300D (W210) . .313,000 miles Wife's car
Santa Rosa population 170,685 (2012)
Total. . . . . . . . . . . . 722,685
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970
Reply With Quote
  #28  
Old 07-21-2006, 05:05 PM
the tenor man's Avatar
Registered User
 
Join Date: Nov 2005
Posts: 152
Blowby

I think the movies are great...I really enjoyed the clickity-clack of the old Mercedes diesels.

I think your problem is a worn out engine. I once had a 240D with that kind of blowby and spent thousands rebuilding the top and bottom. In the long run it wasn't worth it, but my brother and I spent a lot of quality time together. If the body of the car is really nice, it may be worth it for you.

In my opinion, the first clue for me was that the engine just cranks too fast to have enough compression to make it start quickly. Also, I think when you close off the breather tube, it's building so much crankcase pressure that it is stalling the engine.

I would get the compression tested and also perform a leak-down test. I think you'll find low compression due to worn rings.

If it starts and runs well enough for your needs, keep driving it.

2005 Mitsubishi Galant
1989 260E
1987 300D Turbo
1986 BMW 325E
1994 Dodge Ram 250 Van (yech!)
Reply With Quote
  #29  
Old 07-21-2006, 05:19 PM
no-blue-screen's Avatar
Registered User
 
Join Date: Jul 2006
Location: Laurel, MD
Posts: 103
Sounds like your wife or someone was helping out on this one....LOL.

I like on the last one where you yell at her...."OKAY......turn it off!"

__________________
2008 Jeep Grand Cherokee 3.0 CRD (OM642)
Reply With Quote
  #30  
Old 07-22-2006, 02:02 AM
deferr's Avatar
Want a ponton!
 
Join Date: May 2004
Location: Fort Wayne, IN 46835
Posts: 167
Quote:
Originally Posted by no-blue-screen
Sounds like your wife or someone was helping out on this one....LOL.

I like on the last one where you yell at her...."OKAY......turn it off!"

Well not my wife, my girlfriend. She's pretty good about helping when I need it. I agree with most here that blow-by is a good reference point but for the daily driver one is better off to get it all tuned up to spec and then drive and enjoy your classic benz. Thanks to everyone for the insight and I hopefully can create some more helpful videos.
__________________
'78 300D 85,000 original miles drive her daily
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 07:47 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page