04-27-2006, 11:14 PM
Show Printable Version
Email this Post
From: Los Angeles, California
Registered: Nov 2002
$5 Valve Spring Compressor
From: "G. Crowley"
Subject: valve compressor
A $5 valve spring compressor.
Here is a valve spring compressor that will work on DSM DOHC engines. I was faced with finding a valve spring compressor for my son's recently acquired '90 TSi. I went to several chain auto parts stores and possibly the largest independent tool supplier in Los Angeles and came away with a $44.00 tool that I thought might work. Ha, not even close, jaws were still to thick and wide to get into the tight recesses. At that point I'd spent a good 1/2-day searching and was thoroughly disgusted. Then I remembered a tool I'd made some 30 years before to remove the valves on a Lancia Appia which is a narrow angle 12Ί V4 1300cc with cross flow head.
It took less than 1/2 hour to make from some common materials and it essentially it looks like the letter "F". I was in a hurry and my son didn't believe it could be done so please forgive some of the crude construction.
I used a 1 box section scrap from a patio table and a short length of electrical conduit.
Picture #1 shows the completed tool but minus the adapter which actually bears on the spring hat.
Pict # 2 & 3 show the handle is about 10 long, this should be lengthened another 2-4 just from a lever standpoint. The spark plug is welded to the top bar which is about 7 long. The diameter of this tubing must not exceed that of a spark plug socket. The hole centers are about 5 apart, and the lower bar of the F should be about 6"-7" long.
The top of the stem of the F is cut on both sides which can be seen in Pict #1 and then peeled back and removed if desired. A Ό hole is drilled through the stem (lever handle) and the conduit and a 1-1/4 long Ό diameter bolt and nut hold this together. The top bar with plug needs to swing at least 90 degrees so the bar and stem are straight for this becomes the plug installing handle so you can thread into the spark plug holes. The lower bar is slotted as was the handle about 1 depth and drilled as the top bar with nut and bolt.
Not shown is the notched sides and the washer welded flat on the end of the lower bar, this bears on the spring hats and the notches are to remove the valve stem keepers with a pocket magnet. This will remove _all_ valves though not necessarily those associated with a particular spark plug. A second or third hole can be drilled on the stem (lever handle). Screw the plug in until it stops, then back off 1 full revolution. This will allow the tool to swing from valve to valve, it may be necessary that the Ό holes be slightly oversize and double nutted so its not tight for some slop will help things self center. When used on the bench stuff shop towels in the combustion chamber so the valves are supported and cushioned.
The handle can be longer and curve upward so it does not foul on the firewall or the radiator if still on the car. The lengths of the upper and lower bars could be increased so the cams would not have to be removed, only the cam followers. This can be done with a 14-16mm open end wrench placed under the pivot end and pried upward and to the side when the crank has been turned 90 degrees from TDC and all the pistons level to prevent fouling pistons. This may require a shim of another open end wrench to get the proper lever angle. Removing the cam followers is a safe method of changing the timing belt for there is no possible way of bending valves and you can even use the starter to help stretch the belt before final assembly. There may be plenty of oil so cover the pivots with shop towels if using the starter motor.
If you are only changing valve seals it will be necessary to drop the piston down and fill with several yards of string and then bring the piston back to TDC to keep the valve from falling down while compressing the spring. Failure to observe this step will most certainly cause the valve to fall beyond retrieval and the head will have to be removed. The string can be retrieved using a small wire with a hook on the end when the piston is dropped back down
I have the design for a permanent bench mounded tool which will handle most any OHV head including DSMs if anybody is interested. It's just as simple as this to construct.
Any questions, contact GTM on DSMtuners.com.