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Discussion Starter #1
Hi, I seem to have a weak spring on my no. 2 intake valve. I can push the valve in with my finger. I thought I could prevent the valve from moving into the cylinder by pulling the spark plug and levering the valve with a flat head screw driver. Then depress the spring and remove what looks like a ring clip on the end of the valve spring.
I can prevent the valve from moving but I can't depress the spring or remove the clip. My hope is to replace the weak spring without removing the cylinder head. Could be wishful thinking! Any advice would be appreciated. Thanks, Bob
 

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If the spring is that weak, the valve has probably already been hammered and bent by the piston. Run that piston up to TDC and run a leakdown test on just that one. I'll bet it will hiss plenty. If so, you will need to pull the head.
 

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Discussion Starter #3
Valve spring removal with cylinder head on?

If the valve spring is weak it might not seal properly anyway. Can I depress the spring after trapping the valve and remove the springs. Maybe one out of two is bad?
 

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Would a variation of the old rope trick work here? Fill the cylinder near BDC with something like clothesline, rotate the crank to press the rope up against the valve, and swap the spring. Supposedly this works for getting stuck cylinder heads off. Might be worth a few dollars of rope before pulling the head.

Mike Hollinger
Atlanta
 

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Discussion Starter #6
1600 Valve spring removal?

I am in Vail, Colorado if someone in Denver has the tool that would be great. I have a screwdriver in the spark plug hole against the valve tied of with wire to hold the valve tight. Need something to depress the spring and remove the retainer clips on the valve stem. Any ideas/ Thanks, Bob
 

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Clothes line in the cylinder, then run up to compress. That works too.
I'll still wager that valve is bent.
With the clothes line, the valve is held evenly, and a piece of tube on the retainer, struck quickly and lightly with a steel hammer, often pops the locks from under the retainer.
Last time I resorted to this was with a Chevy 396 drag race engine with a broken spring at the track. The car got in it's final run and won. That valve was bent too on later tear down, but ran well enough for a couple of minutes without blowing up!
 

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a piece of tube on the retainer, struck quickly and lightly with a steel hammer, often pops the locks from under the retainer.
Yeah, that will pop the retainer locks off but how the heck do you get the new spring on without the Alfa tool? Probably different with a 396.
 

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Discussion Starter #9
Valve spring replacement / special tool

Thanks for the ideas. Does anyone have a picture or drawing of this special tool? Maybe I can dream up something lever based or hydraulic to depress the springs. Thanks, Bob
 

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Hi Bill,
Richard Jemison sent me the "blacksmiths" retainer reinstallation tool for the track, protecting a transmission part. It took me about 30 seconds to recognize the aluminum tube for what it really was.
The aluminum tube has windows carved in it near one end. The appropriate camshaft being removed, a soft loop of rope is run through a cam bearing, with the cap on. A LONG lever is used through that loop of rope, the aluminum tube being depressed by the lever on to the spring retainer and the windows allow the locks to be prodded into place. This IS a multi person operation, but I have done it, and from the very used condition of the tube RJ sent, I would guess he has as well. There are NO secrets with us old guys!
 

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I'll go take a picture, Bob, later tonight when it's not 103 degrees in there.
 

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Ok, it 88 now and the humidity is survivable. Here we go with the "blacksmith" tool.
I had to hammer this back to (sort of) round for the photo's. First picture is the "tool" sitting on an Alfa spring retainer. Note the window for lock insertion. There is a matching window on the other side.
Next is the tools leverage-applied-end sitting on a retainer and spring to show size. This an is aluminum tube about 5 " long. Finally a picture of the "tool" inside an Alfa follower.
It needs be small enough to fit inside the follower bore in the head. Soft aluminum won't tear up the follower bore if things slip around in use. Clothesline through a cam bearing, large flat lever through the rope loop, press on the "tool" compress springs, insert locks through window (s) and poke into place with a poking-into-place-tool.
Racetrack desperation tools for the brave. Thanks to Richard Jemison for this (damaged) sample. They bend up pretty easy. Hammered round again, this one might be good for one more use.
 

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Discussion Starter #14
Valve spring tool

Thanks Gordon for taking the time to help me out! I'll let you know how I make out and report back on whether the valve is bent or not. Thanks, Bob
 

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With all this mucking around, why not just pull the head and give it a proper going over? If there is a problem with one valve, there might be problems with others...........Regards Ian
 

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Discussion Starter #16
Valve spring issue.

This is a rebuilt cylinder head with 2,500 miles on it! I bought it a couple of years ago.
 

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What it has is a broken outer spring. If it broke at an idle, there is a minute chance the inner spring avoided valve/piston contact, but soon as you got to 1500, 2000 rpm, there will be contact. It only takes a single tap to knock the head out of line with the stem.
Further, modern springs, the good ones, seldom break with correct assembly. If re-used, and shimmed to re-create correct free length, you have a head builder with false economy in mind. Good new ones are not that expensive, and if one old one failed at 2500 miles, you may have another fail at any time.
Bob, I agree with the above comment. Pull the head and take it back to the builder. You WILL end up with a leaky valve, and a lot of effort for a one spring fix on the engine.
To carry this further, should you have another broken spring at high rpm, it could cost you a whole engine!
Just my opinion from my experience.
Below is a snapped off 1600 exhaust valve being examined by my helper, Mr. Weirdwrench. It took out the entire engine.
 

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You can also keep the valve in place by hooking up compressed air from your shop compressor to the spark plug hole. No need to be fishing up line from the compression chamber afterwards. Make sure the exh valve is also closed !!!
You can also make the valve compressor from 1" PVC. Cut a piece of pipe 2" long, glue a metal washer (of the same OD) on top and cut out windows on the PVC pipe. The windows dont need to be large just enough for you to slip the keepers inside.
I found the PVC to be a quicker fabrication than the aluminum unit. FWIW
 

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Discussion Starter #19
Valve spring issues/bent valve?

Hi, When I do a leak down test how long should the cylinder hold air? How long for the air to escape? Thanks, Bob
 

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Discussion Starter #20
Testing for a bent valve

Hi Guys, I pulled the camshafts so all the valves would be closed. I put compressed air in the cylinder with the weak valve spring. I also tried the other cylinders for comparison. In all cases I could hear the air releasing into the timing chain area in a matter of seconds so it was next to impossible to hear air rushing by a potentially bent valve as Gordon has suggested. Any thoughts? I guess the air is blowing by the piston rings into the oil pan area. Thanks, Bob
 
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