Timing Chain Help - PeachParts Mercedes-Benz Forum

bostondiesel · #1 09-29-2009, 05:27 PM

I have a 1983 Mercedes 300D that is pushing 283,000 Miles. My friend and I are going to attempt the timing belt chain replacement. I have searched the forums and still am left with a few unanswered questions, so any input would be appreciated.
First> What special tools are needed for the job?
Second> How long on average should this job take?
Third> What parts specifically should be replaced?
Fourth> Any DIY articles on the how to of the job, I have searched the forums and can't find anything specific?
Thanks in advance for any help! Anyone who has done this job themselves - would love to hear from you!!!!!

oldsinner111 · #2 09-29-2009, 06:36 PM

I'm good at pulling engines and trans.I do all replace repair.When it comes down to a chain,I would rather pay someone.I don't want to screw my engine up.

Diesel911 · #3 09-29-2009, 09:38 PM

Here are the lists of do it yourself links:
DIY Links
http://www.peachparts.com/shopforum/diy-links-parts-category/

http://www.peachparts.com/Wikka/DoItYourSelf

Also the Diesel Giant site has a pictorial on how to do it.

I hope you will buy an IWIS Timing Chain as there is a thread I have seen comparing an IWIS with another make of chain and the IWIS is Clearly better made.

You will find recommendations as to what other parts to replace in the do it yourself threads. And, you are supposed to use a special Timing Chain Crimping Tool to peen over the Master Link. A new one is in the $225-$265 range. However, look for our tool rental program.

rhodes2010 · #4 10-02-2009, 01:20 AM

Before doing the chain please check the existing one and determine
how far off it is from spec.

Really, you probably do not need to do it and will gain very little from all the effort - IMHO.

How its done ?
To summarize the pictorials:
1. Remove valve cover (13mm socket)
2. Lay rag around top of chain and cam gear.
3. With grinder (electric or air) grind away head of one link.
4. Open existing chain and attach new chain to existing chain
on drivers side (injection pump side).
5. slowly and carefully turn engine by hand at crankshaft and
feed chain through engine, keeping tension. I think it is 26mm
socket on crankshaft pulley nut.
6. When old chain comes completely out and you have the two ends
of new chain at top of camshaft insert new link.
7. Crimp with official crimp tool (rentable off the board tool crib).
Or if you have the skill to peen the link, back it up with a steel
block and peen the ends of the links.

I will probably get flamed for suggesting a hand peening on step 7 but
when I did it I did not have this board for a reference, only my FSM and
my garage in 1990. And no access to Mercedes tools .
Today I would probably take the time to rent the tools.

And in conclusion, I don't think my chain needed replacing.
It did not solve my problem.

Is your car experienceing a problem ? Plenty of our cars have not had chains
replaced and we have more mileage than yours.

bostondiesel · #5 10-02-2009, 09:28 AM

Quote:

Originally Posted by rhodes2010

Before doing the chain please check the existing one and determine
how far off it is from spec.

Really, you probably do not need to do it and will gain very little from all the effort - IMHO.

How its done ?
To summarize the pictorials:
1. Remove valve cover (13mm socket)
2. Lay rag around top of chain and cam gear.
3. With grinder (electric or air) grind away head of one link.
4. Open existing chain and attach new chain to existing chain
on drivers side (injection pump side).
5. slowly and carefully turn engine by hand at crankshaft and
feed chain through engine, keeping tension. I think it is 26mm
socket on crankshaft pulley nut.
6. When old chain comes completely out and you have the two ends
of new chain at top of camshaft insert new link.
7. Crimp with official crimp tool (rentable off the board tool crib).
Or if you have the skill to peen the link, back it up with a steel
block and peen the ends of the links.

I will probably get flamed for suggesting a hand peening on step 7 but
when I did it I did not have this board for a reference, only my FSM and
my garage in 1990. And no access to Mercedes tools .
Today I would probably take the time to rent the tools.

And in conclusion, I don't think my chain needed replacing.
It did not solve my problem.

Is your car experienceing a problem ? Plenty of our cars have not had chains
replaced and we have more mileage than yours.

Yes, I am definitely going to check the chain stretch first, no need to replace it if it doesn't need to be. I found a tutorial for measuring chain stretch on a 1984 300SD, would this be the same procedure for my 300D? And as far as the specs, what are they? I have seen conflicts on that issue too on the boards.
The car is not experiencing any problems, it runs great! Just get alot of mixed feelings from the boards, one side says oh my you should have done it by now and others say why bother? So I am flip flopping on it.

#6 10-02-2009, 10:37 AM

If the car has seen FREQUENT oil changes, it will not need a timing chain.

If it does, rolling in a new one is not too tough. There is no need for the special crimping tool. You can back up the link with a Body Dolly and peen the ends with a ball peen hammer. I've done several of them and have never had a problem. If you are one to remove the valve cover frequently so that you can admire the beauty of the crimp made by the multi-hundred dollar tool, then don't use a ball peen hammer.

Diesel911 · #7 10-02-2009, 11:38 AM

There is another issue/s involved with Timing Chain Failure.
When I as what Members thought caused the Timing Chain Failure quite a few said they believed the Vacuum Pump Failed and Parts of the Vacuum Pump fell into the Timing Chain stuff and caused the failure.
When I ask what people though caused the Vacuum Pump to fail some said it was too much end play on the Fuel Injection Pump Timer. And, they felt that is what ruined the Vacuum Pump.
With otheres the Bearing on the Vacuum Pump Drive Arm failed.

Here is one of the threads:

second vacuum pump, help! on a trip-Toronto

Diesel911 · #8 10-02-2009, 11:43 AM

Quote:

Originally Posted by bostondiesel

Yes, I am definitely going to check the chain stretch first, no need to replace it if it doesn't need to be. I found a tutorial for measuring chain stretch on a 1984 300SD, would this be the same procedure for my 300D? And as far as the specs, what are they? I have seen conflicts on that issue too on the boards.
The car is not experiencing any problems, it runs great! Just get alot of mixed feelings from the boards, one side says oh my you should have done it by now and others say why bother? So I am flip flopping on it.

There is a 2mm Method for bot the 300D and the 300SD. However, I do not know if they both have the same degree reading after you do it.

#9 10-02-2009, 12:49 PM

In my experience the only mode of vacuum pump failure that results in other engine damage is when the roller gets loose and decides to go on a journey through the engine. I don't understand what the IP can have to do with this.

Ken300D · #10 10-04-2009, 08:28 AM

You should probably take out the chain tensioner and reset the ratchet on it. Otherwise it may be too tight with the new chain.

Ken300D

Diesel911 · #11 10-04-2009, 01:28 PM

Quote:

Originally Posted by LarryBible

In my experience the only mode of vacuum pump failure that results in other engine damage is when the roller gets loose and decides to go on a journey through the engine. I don't understand what the IP can have to do with this.

Stevo originally told me about too much Timber Bushing end play as a possible cause of Vacuum Pump Failure in answer to a thread that I started asking what people though caused their Vacuum Pumps to fail.

Below is another thread dealing with the above.
Title From my notes:Vacuum Pump Ruined By Too Much Timer End Play
http://www.peachparts.com/shopforum/showthread.php?t=258062&highlight=vacuum

Stevo · #12 10-04-2009, 01:50 PM

Quote:

Originally Posted by Diesel911

Stevo originally told me about too much Timber Bushing end play as a possible cause of Vacuum Pump Failure in answer to a thread that I started asking what people though caused their Vacuum Pumps to fail.

Below is another thread dealing with the above.
Title From my notes:Vacuum Pump Ruined By Too Much Timer End Play
http://www.peachparts.com/shopforum/showthread.php?t=258062&highlight=vacuum

I believe Kerry also had a VP failure due to too much lateral movement of the timing device because of that bushing (Timber Bushing) being warn.