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Valve Seals

1K views 6 replies 5 participants last post by  KRH 
#1 ·
I decided while I was doing the timing chain replacement to do the valve seals as well. A lucky thing is I found a spring compressor (Baum) on the internet for $25.00. So the $12.00 valve seals seemed like a smart thing to do. OK here is my dilema. I am used to stuffing rope into the cylinder and then turning the crank until the piston brings up the rope far enough in the head to lock the valves in place. However this does not seem to work with the M117. I have tried 1/4 rope, 3/8 all to no avail. The rope goes in, and when you put the piston up it does lock the cylinder but the valves still open. I assume there is a quench area that the rope won't go in and where the valves are. Has anyone had luck using the rope method. Ok so if that won't work, I know about the air way but I am skeptical. Will #100 of air hold the valves in enough so when you pull the old seals off and you happen to hit the valve stem it won't drop into the cylinder? Yes I know you need the piston on TDC. Thanks in advance
 
#2 ·
Easy..turn the engine by hand until the piston is at the top of the compression stroke for the cylinder you're working on, at this highest point if a valve does accidentally slip out of your fingers it will come to rest on top of the piston without damaging anything. On other words the valve stem is long enough so that it will not completely fall inside the bore. I did this when I replaced my valve seals, no rope and no air and only require 8 turns by hand.
 
#3 ·
I ended up using compressed air and did not lose a valve, so all good there. Couple of comments. This is a much tougher job than doing the timing chain!!!!! First, moving around the engine compartment causes you to move a lot of the vacuum lines, when that happens a lot of the little fittings and check valves break. I suggest when you do either the timing chain or valve seals to replace all rubber lines, hard plastic and get all of the check valves. Soon they might not be available and over time just moving them will break them. Second find some stinking way to get the old seals off. Yes I ended up using pliers but not an easy task. My suggestion is crimp the valve seals flat one way, then 90 degrees from that crimp them again, then try to grip them and take them out. I did not have valve seal pliers so can't attest to those but let me tell you those suckers were on. Also my old ones were very brittle and for and extra $12.00 when you are doing the timing chain is nothing and my guess is I will have peace of mind on the valve train for a longer time now. Second, have a friend help you. Trying to hold the springs down with that wobbly valve spring compressor is not easy. Who ever designed that was evil.... Yes it works but boy does it flex around. Just when you think you have things under control, then you have to try to get the retainers out all while holding down the springs with that tool. Removing the retainers with a magnet works best, but for installing, use very long needle nose pliers. The magnet is just too strong and it makes things worse. YOu are holding down the valve spring, all the while trying to get the retainer in the right spot, but the magnet is attracted to everything. On the flip side using pliers makes you appreciate a surgeons hands. Drop something and wow, your in big trouble. Luckily for me all worked out well. Oh yes, if someone needs a couple of valve seals let me know, I have seven extra ones. Don't ask!!!! Oh yes to install the seals you need a very good long flat punch or a tool steel drift. You need to slowly tap on each side of the seal a little at a time until they are seated. You can't use a socket since the cam is in the way. Sheesh, onto those little engine shocks next. Those were supposed to be easy too.
 
#5 ·
when I replaced my rockers I felt like a big question mark walking away from the job.
 
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