[KenB]

I have a 1976 Euro-spec 350SL I purchased last year. I am changing the timing chain, cam sprockets, chain guides and tensioner as a precaution not knowing when they were last done. The guide anchor pins are stuck fast into the timing cover. I watched videos and read manuals on this procedure and they indicate the pins come out with minimal force. I ruined two tools trying to get mine out. Tried penetrating oil. Does anyone know a way to free these up?

 

[reno4u2]

Ken would be helpful to know what tools you tried. Guessing one was similar to the ones sold on Ebay. Noticed that Kent at MercedesSource offers a simplier version...have not tried it however...here's the link

https://mercedessource.com/store/gas-and-diesel-engine-timing-chain-guide-rail-pin-removal-tool

Can't say 100% for sure but believe the thread size is 6 x 1.0mm.

 

[Elmer Fudd]

i wouldn't say minimal force

i felt the strain on my spanner hand, i stuck with a 1/4 drive ratchet and through socket, and a longish ring spanner as well as a short spanner. You can overdo the force if you use a big multiplier and then you can make a real mess of it. If they came out really easy, they would chatter out with the vibration of the chain on the guide. are you using a commercial tool, or something you knocked up yourself?
You need to be soaking the little buggers with releasing fluid all the time, I was squirting it in every few turns, as I didn't want any hang-ups.

 

[PanzerPuff]

Does your pin tool look like the one I used in the pic below? I would highly recommend using the right tool.
Search mercedes pin puller on ebay they are $27 with free shipping
Mercedes Chain Rail Pin Puller Engine Timing Tools | eBay

 

[KenB]

Thanks Reno, a Elmer and Panzer Puff. I tried both of the tools recommended. The one from Kent is actually a plastic tube with some 6mm bolts. The EKW tool on EBay is much better but I still managed to break off the 6mm adapter that goes into the pins. I will experiment with different penetrating oils and see what happens. One person suggested applying heat with a torch but I consider that a bit risky.

 

[Elmer Fudd]

Ken, the official ( although dated) MB removal tool

is a slide hammer. If you aren't fussy about taking the radiator out ( the safest option) you could probably have the little buggers out in minutes. How is the thread in the guide you have had trouble with? Is it damaged? if it is, i'd go carefully with whatever tool you use.

For what it's worth, I couldn't wait 10 days for delivery from the US, so I made my own. I tried with the standard steel bolts i have knocking around and stripped the thread on them as soon as things got wiggy. I went to the engineering supply shop, and they fitted me up with some super high tensile nuts and bolts for pennies. No trouble with them whatsoever, they did the job just fine. I was using Plus Gas releasing fluid, and some German rust dissolver which I had lying around. They did the trick. They smelled pretty much the same, but my money would be on Plus Gas every time. My old man swore by it, and some of the kit he worked on meant he knew what he was on about. He squirted it like holy water at a cardinals' convention. I keep the family tradition going.

 

[Kernow101]

It does take quite a bit of force to break these free initially and be very careful with home made pullers, you need to use a high quality bolt so it does not snap. Talking of 'snapping' be very careful with the top left pin on the RHS, it is quite difficult to get the puller flush with the surface, due to ridges surrounding the pin. I did not pay enough attention and because it was pulling at an angle the bolt snapped in the pin and was a bugger to get out!!!

 

[Aussiemerc]

Pin pullers

Keep using penetrant . Using a pin puller worked well for me

 

[KenB]

Thanks Kernow and Aussie and thanks again Elmer. I will try these suggestions. I managed to extract the broken adapter from the one pin and coincidently it was on the upper left pin on the right bank. I will check to make sure I'm pulling these straight.

 

[Kernow101]

With the upper left pin you have to use the plate which comes with the puller (I was using the EKW tool), even then its still at a slight angle so you will have to level out with a thin washer maybe. That one and others were very tight on my machine, and came loose with a loud 'crack', which made me think I had broken the puller again! I did not on level it on my first attempt hence with the extra force needed to pull the sticky pin and the angle, the puller sheared. Thats after using PB blaster on it. Others just slid out easily.

 

[Elmer Fudd]

+1 on all that cracking

mine sounded like a medieval torture chamber, with me being tortured. In a possibly vain attempt to make it easier for the next time, when i put ( read whacked) the pins back in, I used copper thread compound on them. Given the tight interference fit, i doubt any will have made it into the bore, but one lives in hope. What i didn't want to do was be tempted to clean them up with any abrasive material. that would have been bad.very bad.:eek

 

[KenB]

Success!

A report on the resolution of my problem. I tried another EKW puller tool and promptly broke the 6mm adapter that come with it. I took Elmer's advice: removed the radiator and used a slide hammer. A moderate amount of pounding removed five of the six pins, one was stuck hard. I had a theory that carbon build up on the pin was keeping it from getting past the interference fit in the head. I used brake clean and a brush to clean up the pin and eventually it came out. Thanks to all for the suggestions.

 

[canswede]

Yes, be sure to use washers to level the puller. Mine came out without trouble, I had purchased MercedesSource puller that is very basic but in the end it worked, with some extra washers.

 

[DudsyBenz]

I just pulled the pins on my 380sl with the following homemade pin puller. It's easy to make and based on a design by "earnest37" on the peachparts forum.

380SL Tension Rail Pin Removal - PeachParts Mercedes ShopForum

I made mine a bit smaller in length than the earnest37 design. It worked very well. The advantage is it 'self-levels'... once the centre bolt is threaded, tighten the outer bolts evenly. Ensure the centre M6 x 1.0 bolt is high quality; I used a 12.9 grade.

 

[roncallo]

A slide hammer used to be the standard tool. Mercedes had one with a flat slide hammer to take up minimal space and do it with the radiator in place. It is far more effective than the draw type tool.