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-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 04-10-2006, 08:59 PM
Registered User
 
Join Date: Dec 2005
Location: Los Angeles, CA
Posts: 340
IP Timing

I am getting about 17 MPG, i Have had the injectors done,good compression but i just checked my IP timing and it is about 7 Degrees BTDC (Checked several times), My question is can this cause low MPG and rough idle, also i see no black smoke.
Thanks
__________________
1979 300D.
Reply With Quote
  #2  
Old 04-10-2006, 11:15 PM
Registered User
 
Join Date: Nov 2004
Location: Nova Scotia, Canada.
Posts: 6,510
It is going to hurt to some extent of course. The fuel is being injected late at a lower compression point. Or to put it another way the burn interval tends to be on the backside of the ideal peak. Less ability to develop power for the engine will automatically mean more fuel for the same performance level. I would check the chain stretch as well before moving the pump. If it's okay then reset the pump. It certainly will not hurt and should be done hopefully giving you a good gain in fuel milage. I know you love your 17mpg so much your going to try it.
Reply With Quote
  #3  
Old 04-10-2006, 11:46 PM
Banned
 
Join Date: May 2002
Location: Blue Point, NY
Posts: 25,396
Quote:
Originally Posted by hawthorne90250
I am getting about 17 MPG, i Have had the injectors done,good compression but i just checked my IP timing and it is about 7 Degrees BTDC (Checked several times)
What method did you use to check the IP timing?
Reply With Quote
  #4  
Old 04-11-2006, 12:43 AM
Registered User
 
Join Date: Nov 2004
Location: Nova Scotia, Canada.
Posts: 6,510
The rough idle might be something else other than the delayed injection pump timing after remembering that I did not comment on it. The best thing one can do when faced with an engine or performance that is substandard to the average example is a general tune up. By systematicaly doing it you tend to pick up faults along the way and many small things combined can lead to really poor performance. Or as in your case sub standard milage. My gut feeling is put your pump where it belongs after establishing your chain stretch is reasonable and correcting the cam timing with an offset key if required. It is very important to inspect your chain guides as well. Then do a compression check. Get your injectors checked and matched if you do not know their status. If compression check is good and cylinders are reasonably close . Compression tester is as cheap as 9.95 at hudsons I am told so there is no longer a reason not to have one if you cannot borrow one or have one already. Grab a digital meter that can read milli volts.. Read the output of all your glow plugs. If they are equal you should be good to go. If they are not then swap the glow plugs around to verify the plugs are not the factor. If the mixed voltage readings continue there is most likely a problem with the pump. Next a volume flow test to make sure pumps output per fuel element is simular. If volume test checks out you probably have a sequential pump timing problem or enough of an indication that the pump needs retimed to itself not in refference to the engine. Of course before any of this the first thing to always do on one of these engines is to set the valves. They are famous for all kinds of symptoms that are valve clearance related. If an engine makes all these tests and adjustments with reasonable equal compression it's going to hum like a pussycat. It's also all in the archives. Basically as soon as I hear rough idle in refference to these engines
I know it's time to do a total tuneup if I have no knowledge when it last had one. You of course can stop as soon as you have located the problem but for maximum performance and milage you should do it all. Your airfilter is reasonably clean by the way? it will cause reduced milage combined with excess smoking. I would expect that a rough idle may also be caused from too much air entering the fuel system as well. You have to keep an open mind. Most of the above proceedure is time rather than money. It is my hope we can restore or improve sequential timing errors related to aging and people adjusting things they should not have. But first we have to establish without a doubt that is the problem plauging the engine and be prepared to have a pump shop do the corrections it if we fail. But once the fault has been absolutly isolated there will be no reason not to try to improve the situation and my guess is it will turn out well for us once understanding and application are understood. It is not rocket science and we want to properly repair these old cars at minumum cost. The last thing we want to do is spend money where it is not needed as in most cases it will not be hard to find another area of the car that can absorb it. By the way if you want to do a rough check of your injectors at little cost. Just move one after another into the same cylinder hole. Read the milli volt output of the glow plug. If they are say all within .2mv you kind of know they are all the same. Thats basically what you are sending them out to find out. Also if only one injector gave a large variation to the voltage reading that is the one to send out. The others are known good by dynamic checking. All the above mentioned items pertaining to using the milli volt reading approach are a probe into the unknown at this point to some extent. So rather than what to do are more food for thought but I have passsed the point myself of only considering them as abstact Ideals. These tests will function well I believe if the user understands exactly what he or she is doing. Also there will be initial resistnce and that is normal. But to enjoy these cars that are on there way to becoming antiques and keep maintenance costs in line we have to prove the validity of cheap and effective tests if possible to keep our cars running as well as possible.

Last edited by barry123400; 04-11-2006 at 01:24 AM.
Reply With Quote
  #5  
Old 04-11-2006, 08:56 AM
dannym's Avatar
I'm not here
 
Join Date: Oct 2004
Location: Deltona, Florida
Posts: 2,360
Quote:
Originally Posted by Brian Carlton
What method did you use to check the IP timing?
That's the question. Being that you stated you already checked your injectors and compression.

If you did the cam mark method and got the same reading a number of times then it's more than likely a good reading. However I would not choose a woodruff key for my engine on a "More than likely" reading. I would get myself a dial gauge set and do it the right way.
Click here for instructions on checking timing chain stretch

Then pick a woodruff key and check your IP timing. Only adjust if it's off after the woodruff key is installed.

Of course you should replace your air and fuel filters too.

Danny
__________________
1984 300SD Turbo Diesel 150,000 miles

OBK member #23

(\__/)
(='.'=) This is Bunny. Copy and paste bunny into your
(")_(") signature to help him gain world domination
Reply With Quote
  #6  
Old 04-11-2006, 09:41 AM
Banned
 
Join Date: May 2002
Location: Blue Point, NY
Posts: 25,396
Quote:
Originally Posted by dannym
That's the question. Being that you stated you already checked your injectors and compression.

If you did the cam mark method and got the same reading a number of times then it's more than likely a good reading..............
Danny, he's checking IP timing.......not cam timing.

The methods would be "drip" or "RIV" or "pulse timing".
Reply With Quote
  #7  
Old 04-11-2006, 10:40 AM
Stevo's Avatar
Registered User
 
Join Date: Apr 2002
Location: NW WA
Posts: 6,286
Quote:
Originally Posted by hawthorne90250
I am getting about 17 MPG, i Have had the injectors done,good compression but i just checked my IP timing and it is about 7 Degrees BTDC (Checked several times), My question is can this cause low MPG and rough idle, also i see no black smoke.
Thanks

Like was already mentioned, the rough idle might be something else.

A friend of mine (good mechanic) bought a hard starting 240D. He checked the timing and it was 6 degrees BTDC
The only noticeable result of the timing being off that far was hard starting.
__________________

1985 Euro 300TD 5 spd 220K
1985 Euro 240D 5 spd 130K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"
Reply With Quote
  #8  
Old 04-11-2006, 10:50 AM
Goodentight
 
Join Date: Mar 2006
Posts: 218
The crank drives the pump and then the cam. The pump is infinitely adjustable (if you consider that you can jump teeth on timing chain for additional adjustment). Because both cam and pump timing are referenced to the crank, they really don't have any impact on each other. The pump being out of time does not affect the timing of the cam or vice versa. Even the chain being stretched does not mean that the cam and pump cannot be correctly in time once adjusted.

Andrew
Reply With Quote
  #9  
Old 04-11-2006, 11:42 AM
Registered User
 
Join Date: Nov 2004
Location: Nova Scotia, Canada.
Posts: 6,510
Since he appears to be out a lot on pump timing I just though the chain should be checked for stretch and the cam timing put back also as it might be off. When he checks his chain it might be stretched above allowable limits. There is only one accurate method of checking actual timing of the cam to the crank pulley. That proceedure gives you the chain stretch factor as well of course. You have to use a dial gauge as in the archives as someone stated. If he does not do things in sequence he may land up backing up to some extent or leaving a marginal situation behind as he goes along. I think rough idle has been documented in the past on these engines as well if cam timing is off. At least he is ahead somewhat as apparently his compression is good and injectiors already done. He should get through this in my opinion as he has already not been intimidated by checking his pump timing or changing his injectors out. A lot of proceedures depend on how comforatable an individual is to do them. He sounds like he is easily up to them. I7 mpg is pretty bad though and does deserve some serious attention. That is unless he forgot to mention that he is driving around with twenty women in his car all the time of course. But I kind of rulled out that senario as then the 17 mpg would be the least of his concerns. It is always what you forget that gets you. For low mpg it never hurts to make absolutly sure you do not have a fuel leak somewhere as well. I am pretty sure he will locate his problem systematically as well.
Reply With Quote
  #10  
Old 04-11-2006, 11:48 AM
Stevo's Avatar
Registered User
 
Join Date: Apr 2002
Location: NW WA
Posts: 6,286
[QUOTE=libbybapa The pump is infinitely adjustable (if you consider that you can jump teeth on timing chain for additional adjustment). Andrew[/QUOTE]


Wouldnt it be eaiser to pull the pump, and reset it if the correction needed is beyond the adjustment of the slotted bolt holes?
__________________

1985 Euro 300TD 5 spd 220K
1985 Euro 240D 5 spd 130K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"
Reply With Quote
  #11  
Old 04-11-2006, 11:57 AM
Registered User
 
Join Date: Nov 2004
Location: Nova Scotia, Canada.
Posts: 6,510
If thats what it takes its okay. First though it would pay to find out the why it's so far out. Right along I have suspected an elongated chain but just as a possibility. Another couple of possibilities is someone accidently put the pump timing off and I consider that not likely but still possible. Of course also imagine the pump has worn and aged perhaps over the years or perhaps someone messed it up a little when timing the last time. The primary object is to get things back on track but again keeping an open mind. Unfortunatly other than changing oil and filters out a lot of my aquisitions have perhaps not had a serious tune up for perhaps twenty years. If they are running well with a smooth idle, decent power,start easily, fuel consumption is average I just leave them alone other than valve adjustments checked periodically and fuel filters occasionally as by and large our local fuel is pretty clean. Right now I am looking at a car on ebay and banging my head against the wall at the same time. I am old enough to know better. My self justification being that pretty shortly there may be no reasonable examples left of the 87 sdls except at prices I will not be able to afford or justify.At least it's totally rust free. The wife does not really mind other than wondering if I may land up with more cars than the mercedes company I imagine.

Last edited by barry123400; 04-11-2006 at 12:43 PM.
Reply With Quote
  #12  
Old 04-11-2006, 04:34 PM
Stevo's Avatar
Registered User
 
Join Date: Apr 2002
Location: NW WA
Posts: 6,286
Quote:
Originally Posted by barry123400
The wife does not really mind other than wondering if I may land up with more cars than the mercedes company I imagine.

LoL...I have found that if I keep em outa sight, I can sneek in quite a few

Timing is such a PIA (least it was for me the first time) that most folks just dont do it. On that one of my friends that was out 6 degrees, it belonged to a friends mom that owned it for many years. It started hard from the get go, they rigged two batteries so they could start it, a fairly low mileage, nice 240D. When mom died the son sold it to a friend and he found the timing WAY out. NOBODY ever thought too check the timing, including me And like I said the only problem was not starting well. The son speculated that the car came from Germany that way.
__________________

1985 Euro 300TD 5 spd 220K
1985 Euro 240D 5 spd 130K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"
Reply With Quote
  #13  
Old 04-11-2006, 05:14 PM
OMEGAMAN's Avatar
Registered User
 
Join Date: May 2005
Posts: 705
Cool

Go ahead and adjust your injector pump timing ans you can use this method it works great. EDIT: this link is bad http://diymbrepair.com/easley/iptiming.htm

Mine was off about 6 or 7 deg ( I cant remember) when I adjusted it I got a huge jump in power and fuel efficiency, better idle, cold start, the works.

I think the easiest way to do it is to remove the fan and shroud from the front of the engine so you have some room to work. Front crank bolt is 1/16.

You probably need to adjust cam timing with a new woodruff key but I bet if you just do the pump timing now you'll be very happy and can horse around with the cam timing when you don't have more important things to do like make money, spend money, get laid, beat your kids, drink beer. Good luck! and tell us how you made out.

Last edited by whunter; 10-25-2006 at 04:19 PM.
Reply With Quote
  #14  
Old 04-11-2006, 06:11 PM
Registered User
 
Join Date: Nov 2004
Location: Nova Scotia, Canada.
Posts: 6,510
Omegaman scores some real points. Since these cars are a hobby for most of us the approaches will vary to some extent depending on the end result you really want. Almost any approch that leaves the person happy with the results is okay for them. I probably tend to overfix or come close to it in general. That gets you a perfectionist label deserved or otherwise. I know that I never tend to leave any underlying condition behind for several reasons that perhaps only pertain to me in general. Guess its just a personal prefference kind of thing. Neither system is really right or wrong. They exist side by side. Different strokes for different folks comes to mind.
Reply With Quote
  #15  
Old 04-11-2006, 06:49 PM
Registered User
 
Join Date: Dec 2005
Location: Los Angeles, CA
Posts: 340
IP Timing

The chain was replaced about 40,000 miles ago(according to the maintenance docs).
I used both methods to test ,Drip and the one listed here
EDIT: this link is bad http://diymbrepair.com/easley/iptiming.htm.
I will adjust the IP tommorow.
Any one know which way the pump has to be moved to retard the timing.?
Thanks for all the help.
I wonder was it adjusted before with the old chain and not re-adjusted after installation of the newer chain?.
__________________
1979 300D.

Last edited by whunter; 10-25-2006 at 04:20 PM. Reason: this link is bad
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 10:54 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, 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