I now have the spark plug adapter and retriever that I bought from Samstag. On a side note, I bought the diesel valve adjustment wrench set at a shocking 75 bucks! At least I'll make that back over time

In order to access the crank bolt, it seems I need to remove the fan. Can I accomplish this by merely removing the 4 small bolts on the trailing edge of the fan?
Plan B might be removing all plugs and then turning the engine with the power steering pump bolt. Could I then attach a bar to the crank from underneath and then wedge it against the ground to keep it from turning? I think I came across that method in a thread somewhere on this board.

As for the new stem seals, one of them has a flat top, the other has an angle on the top edge. Any insight into which is which? They are outwardly identical otherwise to my naked eye.

Has anyone had to renew rotocap, keepers or spring retainer?

Also, the manual stresses the deburring of the vavle stem at the groove. Can anyone shed light on this step? It seems that what they are after is a smooth surface in this area to prevent problems with the spring retainer and keepers. What method would one use to debur?


And I think final question for now is valve guide condition. I'm sure this car needs a valve job badly but I don't want to go that way. Tim, I was surprised when I read about you removing the guide with your fingers and placing a new one in!
What's a method to check guides with the heads on? How wiggly should they be?
Hopefully I could just pull a few of the really bad ones out the top like Tim and place a new one back in.

Thanks for all the help!

__________________
63 220S W111
76 300D W115
2013 VW JSW TDI M6

previously-
73 280 SEL 4.5
86 300E 5 speed
2010 VW Jetta TDI M6

The fan comes off by the four bolts.
With the power steering pump, you will have to put like a crescent wrench on the looser belt and push it tight so that it will grab and turn over the engine.
My valve seals werent like that. My exhaust had a bigger hole on the of them than the intake.
The valve guides shouldn't be wiggly hardly at all. If they come out easily, then they are bad.
Putting a new one in with the heads off was not that easy.
First measure the bad one and get one that is slighty oversize from that. You might even have to shave a little off or use some lubricant to get the new one in. All depends.
You have to somehow tie off the valve so that it doesn't drop into the cylinder. Then you have to get something(I used the bad valve guide) to hit instead of the top of the new guide and SLOWLY hit the new one in with a hammer(you can't damage the new one though. This took about 30 minutes to put one in. We had to tap in very slowly all around.
Tim

To check valve guide clearance, drop the valve a bit to clear the seat and wriggle side to side. If you can feel it move, the guide is worn out.

If you have some worn guides, it's time for a valve job -- do the chain and upper chain guides at the same time.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

I'm going to post conflicting advice here but for a good reason:

DON'T change the upper guide rails UNLESS they already have been replaced with the solid plastic ones. The metal-backed rails that are stock on the 4.5's are FAR superior to the plastic ones. Mine have 140K miles and show much less wear than the plastic ones on the 420SEL that was in the junkyard (due to BROKEN RAILS!). The plastic rails break, the metal ones do not!

I heard you can get new "inserts" or whatever for these. I have yet to look this up or confirm it though.

__________________
Current:
2021 Charger Scat Pack Widebody "Sinabee"
2018 Durango R/T

Previous:
1972 280SE 4.5
2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi"
1999 Chrysler 300M - RIP @ 221k

Yikes! Boy do I have problems now.
I really didn't want to do a valve job on this car.

I started on cyl. 5, the plug was badly fouled with oil.
After losing the battle against the stubborn keepers, I finally got them out.
I then began to look at removing the old stem seal on the exhaust vavle. Using a small needle nose vice grip, I attached it with some light grip and gave it a gentle to moderate tug upwards. The stem seal came off along with about a third of the visible valve guide that broke off. . . darn.

I don't think I did much wrong. The manual suggests using pliers or a screw driver to remove the old seal. Also, I was really only an exploratory attempt at removing the seal! I really wasn't expecting it to come off.

The seals are hard pink plastic with wire coils at the top and bottom of the seal. They look like they could be really old, I suppose they could be original. My new seals are rubber.

The rest of the guide seems tightly in place. How am I going to get that darn thing out!?

Most of the other plugs looked okay, from light brown to dark brown in color, with two being covered in white crust.

Any and all brilliant suggestions from the talented, wiser than me members of this forum are now welcome!

__________________
63 220S W111
76 300D W115
2013 VW JSW TDI M6

previously-
73 280 SEL 4.5
86 300E 5 speed
2010 VW Jetta TDI M6

The guide should not have come out. You didn't do anything wrong. I would say try as hard as you can to get that valve guide out the rest of the way to avoid doing a head job.
Tim

The guide is not going anywhere but that doesn't really matter 'cause I dropped a valve. I let go of it before the compressor had built up enough pressure and the piston was not at TDC because I was moving the cam to get the adjuster off so I could get a better angle at the guide. . .

Now I need to find out what tools I can borrow, what I can compromise with from McParts and what special tools I absolutely have to buy.

I worry that my lack of experience will cause me to destroy the engine completely in some way. At least in that event, I only paid $500 for it.

Tonight I guess I can start by pulling injectors and the intake manifold.

This will be fun.

__________________
63 220S W111
76 300D W115
2013 VW JSW TDI M6

previously-
73 280 SEL 4.5
86 300E 5 speed
2010 VW Jetta TDI M6

I gotta tell ya joshhol, from following your thread here, I'm thinkin any work in my future on the valve seals/valvetrain is gonna be farmed out so I don't have to suffer nor do I have to watch! Hope things shape up soon for ya...

>>> I dropped a valve. I let go of it before the compressor had built up enough pressure and the piston was not at TDC because I was moving the cam to get the adjuster off.

Something risky that might retrieve the valve is to push it back up with the piston by rotating the crankshaft *backwards*say, 20 degrees or until a chap magnetic retriever will recover the valve...... First determine how far the valve has fallen by probing the valve guide to see if the valve has fallen completely into the combustion chamber in which case you are SOL.

Meanwhile you might want to think about retracing your steps and getting the valve seals professionally installed. Am thinking most shops bill this at 6-8 hrs, maybe more for the V-8.

As I've said, valve seals are about as tough as it gets for high-tech DIY work. Hell, it took me 2 full days doing my own valve seals on my 220Sb long time ago....... and this is with background experience pulling engines, trannies and workin on cars all my life.

Pulling the cylinder head DIY is much easier by comparison, but more costly with ensuing parts and machine shop work for complete valve job. If the valve you've dropped is irretreivable then this is the logical path to follow.

And dont ever say "its just a $500 car"...... lately the 108's have been moving like hotcakes on ebay. Arguably, these are the finest MB luxury sedans available. Its litterally a lifetime car, if you want it to be.

It's something I've noticed too... in the past 6 months the avg going price for most 108's has nearly tripled!

__________________
Current:
2021 Charger Scat Pack Widebody "Sinabee"
2018 Durango R/T

Previous:
1972 280SE 4.5
2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi"
1999 Chrysler 300M - RIP @ 221k

When we were doing Tim's, we dropped a valve. I'll bet you can still retrieve it if you have a magnet on a wire that could go through the valve guide and pull the valve up by its stem.
Good Luck
David

__________________
_____________________________________________

2000 Honda Accord V6 137k miles

1972 300SEL 4.5 98k miles

_____________________________________________

Hell yes, Tom..... its like the "200 series" ebay section http://listings.ebaymotors.com/Mercedes-Benz_200-Series_W0QQsacategoryZ6329QQsocmdZListingItemList ......provides daily stock market report on practically ALL Vintage MB's.

Lately everybody is dumping their 4 cyl stick shift diesels for peanuts and 108 4.5's are in extremely high demand!!! My opinion on this market shift is that consumer confidence strongly feels that cars getting less than 20mpg are notso bad compared with hassles of cold starting slothful diesels in cold weather.

Anybody who thinks *any* 108 is just a hunk of crap $500 car is out of their mind........ Josh, you could probably pull your own cylinder heads and throw $500 into professional machine shop valve job - then make a few hundred bucks selling the car - assuming cosmetics are decent and this is what you've got in mind.

i agree there, the 108 is one of the best cars ive ever driven, and its amazinly cheap for what it is too. i cant figure out why. show me any other car that will run for 30 years, with not much more than normal maintenence.

Thanks for the replies. In my defense on the $500 dollar car comment, any "civilian" I know looks at the car, then looks at me like I'm crazy. But, I know what a 108 is. I think any other non Mercedesshop person would throw their hands up and call the junkyard on a car like this. Keep in mind it is cosmetically pretty much a wreck.
I hope someone will buy it after all is said and done.
I've thought about selling it to someone to part it out, but I think the experience gained just by seeing this job all the way through will teach me volumes and help me avoid mistakes on my other two Nicer (cosmetically that is) Benz's. I definitely love 108's and am glad to hear their value is increasing. My only complaint is the horrendous gas mileage, which will only get relatively worse as the years progress. Those who are swapping thier diesels for 108's likely have weekend use in mind.
Sad thing is the diesels will be neglected now.

The valve, is all the way in. I spent a good amount of time trying to find it with magnets and wire, but it is almost as if it has dissappeared. Besides, that is a moot point because the valve guide broke and won't come out.

Kpb- Here's what I think went wrong: On the first seal that I attempted to remove, the guide broke. What I figured out on the next seal was to remove the small wire that was coiled around the top and bottom of the seal, then pry it off using TWO screwdrivers on the bottom of the seal. Make sure not to dig the screwdrivers in deep to avoid scratching the guide or stem. It came off quite easily (don't know if this will work as well on the others though). I guess the thing to do is remove any kind of retaining wire or clip on the old seal before trying to remove.
Had I not broken the guide (which must have had a fracture in it) I could be almost done with the job. However, replacing a stem seal over a possibly fractured guide would not have resulted in an enduring fix, most likely.
I wouldn't be scared off this job but it's up to you. This was a spare car that I could afford being grounded for the time being. If you keep air in the cylinder, keep the piston close to TDC and take care in removing the seals, you should be all right. If anything, go into a junkyard and practice on a few.


So, from here it is time to shift gears into cylinder head removal (LH). I can't do any of the other seals because I dare not rotate the engine.
Some searching is in order. Should I start a new thread?

Thanks for all the help everyone. I look forward to the continuation of this saga with your support.

Have a good one!

__________________
63 220S W111
76 300D W115
2013 VW JSW TDI M6

previously-
73 280 SEL 4.5
86 300E 5 speed
2010 VW Jetta TDI M6

In aluminum heads, the valve guides are usually made from a relatively brittle bronze material.

As for owners abandoning their diesels for V8s, that may change if gas prices skyrocket to record levels.

Happy Motoring, Mark

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DrDKW