How to put a counter hold on the camshaft - PeachParts Mercedes-Benz Forum

Damian · #1 05-28-2007, 04:56 AM

I am in the process of changing my timing chain and guides, and can not find a place to hold the cam shaft to anable me to remove the bolt holding sprocket in place on the left hand side cam.

The manual shows the use of a retaining wrench part 116 589 01 01 00, but where are the actually hold on to ? Surley not on a lobe and the rest is all round with no flat sides to be found.

any help appreciated

regards

Damian

dpetryk · #2 05-28-2007, 08:32 AM

I have always used an impact wrench to remove them. No need to hold anything. But if you dont have one then I would loosen the bolt while the chain is still attached. Or pass a rod through the gear and lodge it against something to keep it from turning.

ctaylor738 · #3 05-28-2007, 06:06 PM

You can also counter-hold the crank with a 27MM socket on the balancer bolt. Another way is to hold the cam with large vise grips between the lobes.

Damian · #4 05-28-2007, 11:01 PM

Guy's

Do you think using the chain to hold it, as in the case of using the rattle gun or balancer mounting bolt, would put to much stress on the chain?

When I finish the job and re-ension it should I use loctite on the bolt?

Regards

Damian

dpetryk · #5 05-29-2007, 11:42 AM

Thats one tuff chain. Heaven help you if the chain will not hold it.

Damian · #6 06-03-2007, 03:03 AM

Thanks everyone,

I managed to get it undone by puting a small extention bar through the holes in the sprocket.
I was a bit worried about turning the cam and have the chain skip a tooth down in the engine, as the tensioner and the top rail was removed ( I cable tied the chain onto the gear though.

Waiting to get some more pivit pins so I can continue

Damian

ewenjo · #7 06-12-2007, 12:38 PM

I recently changed my chain and guides and was faced with the same issue. Very carefully I used a pipe wrench and held the cam shaft between the front lobes and loosened the sprocket nut. Worked fine.... just have to make sure you don't mar the lobes or allow the cam to slip also had to remove the oil tubes to get the wrench clearance. This was a good thing since the bearing oil feeds should be changed anyway. They pop out with a gentle prying and are "cheap".

tgolden · #8 06-12-2007, 04:47 PM

Quote:

Originally Posted by Damian

The manual shows the use of a retaining wrench part 116 589 01 01 00, but where are the actually hold on to ? Surley not on a lobe and the rest is all round with no flat sides to be found.

The camshaft holding wrench is made of aluminum and secures the camshaft by holding the lobe. Because the aluminum wrench is softer than the camshaft, it will not harm the lobe.

Baum Tools sells a camshaft holding wrench, item # 11-0101. The link to their site is below. Regards

http://www.baumtools.com/

Alkraut · #9 06-12-2007, 08:04 PM

Quote:

Originally Posted by Damian

Thanks everyone,

I managed to get it undone by puting a small extention bar through the holes in the sprocket.
I was a bit worried about turning the cam and have the chain skip a tooth down in the engine, as the tensioner and the top rail was removed ( I cable tied the chain onto the gear though.

Waiting to get some more pivit pins so I can continue

Damian

You may find that with the sprocket still in the chain, you won't be able to move the chain over enough to handle the guide rails. I used an "automatic" prick punch to make a mark on the sprocket right next to the chain, and a small file to make a mark on the chain link right above it. Some people mark the chain and sprocket with paint spots. I did not want to risk having it come off. Keep tension on the chain as you take out the sprocket, and remember to put the sprocket back facing the same way. I used a bungee to hold the tension on the chain to the hood, and a stick to keep the hood from pulling down. Don't drop the chain down the hole! It will take some trial and error to get the sprocket back in the same location. The key/keyway should then line right up. Good luck.

Damian · #10 06-18-2007, 10:44 PM

Well I have finally put all the rails back in and put the cam gears back on. The right hand sprocket was a bit tricky to put back, on as the preload from the valve springs shifted the position of the Cam slightly when the sprocket was removed.

I managed to slightly rotate the crank back to get enough slack in the chain to tap it back on. The sprocket looks a bit out of line with the mark when all the others are lined up, but I'm sur it will pull back when the new tensioner and chain is installed.

I feel the right hand mark was slightly off before I started the job as there must be a bit of stretch in the old chain or the old dampener didn't have enough tension on it.

Enyone know if it's o.k. to rotate the engine by hand with the chain tensioner out? I can see if the chain jumps on the cams , but I was wanting to know if it could skip a tooth down on the crank where I cant see.

I guess it should be O.K. as the book says you have to have it removed, when you feed the new chain in.

Damian

Alkraut · #11 06-19-2007, 07:33 PM

I had no issues with rotating the engine with the tensioner off. Just make sure you rotate clockwise. As you found out, a "loaded" cam will jump. Since my cams had lugs to put a wrench on, I was able to line up the key without rotating the engine. As long as you kept the sprocket teeth in the same location on the chain as when you started, the timing should not change. If the marks you put on the chain and spocket line up, and the key/keyway went in, you should be good. After you put your tensioner on, rotate the engine around until the indicator is "Top Dead Center" TDC on the crank. Make sure spark plugs are out, as it will be easier to rotate. Check to make sure the right passenger camshaft front two cams (number one piston) are off the followers (compression stroke). If not go around one revolution to TDC and check again. At this point the marks on the camshaft should line up with the sprocket marks. If the chain has some stretch, the sprocket marks will not quite have reached, but very slight (hopefully).

Damian · #12 06-24-2007, 03:30 AM

Well I finally finished puting in my new chain and tensioner and made sure it never cam away from the sprocket at anytime.

The timing marks however still look to be out by the same amount as before, when the Dampener is on 0 deg the RHS sprockets mark is on the right past the TDC mark on the housing. ( This equates to about 15 deg on the Harmonic Dampaner). The LHS sprocket line up perfectly, I though this was due to stretch in the chain.

The RHS head seems to have had work done to it before as the oil tube fittings are a different color to the other side and there is some red text on the front like it's been away to a shop for a rebuild.

Is it possible that who ever done the work before had the cam out by 1 tooth in the clockwise direction? The engine seemed to run fine for the 4 years I've hade it.

I removed the tensioner again and moved the chain forward one tooth, put the tensioner back in, turned the engine over by hand several turns and all the marks seem to line up much better.

Now the mark on the RHS sprocket is the width of the mark itself to the left of the mark on the housing.

What do you think ?

Regards

Damian