Valve Spring Replacment

[OneEightSeven]

Hey gang. So I ordered some stuff today. My arm was twisted into getting something for my birthday and I decided for some basic goodies:

- Yella Terra 1.9 rolling rockers from ZZP
- Meziere electric water pump from ZZP
- Comp Cams 105# valve springs from ZZP

So I know how to do the rockers, pushrods (part of yella terra package) and the water pump no problem. However what is the best way to do the valve springs? I keep seeing mixed information.

Some say you just need to compress the cylinder with an air compressor to ~80psi and it's fine and a few people said to go to TDC before compression. Some say you can just go to TDC and the valve won't fall far enough to be a problem. Others say to shove rope in instead of air pressure. So basically, what is my best method for ensuring I don't have to tear he head off the motor?

[LETZRIDE]

Re: Valve Spring Replacment

just put compressed air into the spark plug hole and you will be fine...this is what I did...just make sure your air doesnt run out lol. I shouldnt...but just be mindful that you might want to hold the valve if/when your compressor kicks on...just for safe measures...even though it should still be ok.

[3.4grapeofwrath]

Re: Valve Spring Replacment

I use the compressed air method also. I'm sure the rope method works fine if you don't have air available.

[caspernicus]

Re: Valve Spring Replacment

I just put the piston at TDC when I did mine.

[OneEightSeven]

Re: Valve Spring Replacment

I'm a little worried doing the compressed air method. What is the minimal you need compressor wise? I have a cheapo oil-less compressor I use to pump tires and run an air brush. I think it makes like 50 or 60psi and has a gallon tank or something. If doing it at TDC how far will the valve drop? Will it be a lot harder to get the spring on if the valve is not up all the way? I'm planning on changing out the seals too just cuz I'm there. Getting some felpro seals (seem identical to zzp's premium ones) from oreilly's.

[cam98aro]

Re: Valve Spring Replacment

it will be a lot easier to put the piston at tdc than to use compressed air or rope IMO.

but either method will work.. most of the time the valve wont even drop into the engine, it will get stuck at the top.. you will usually have to file the top of the valve to actually get it to go through the head

[OneEightSeven]

Re: Valve Spring Replacment

it will be a lot easier to put the piston at tdc than to use compressed air or rope IMO.

but either method will work.. most of the time the valve wont even drop into the engine, it will get stuck at the top.. you will usually have to file the top of the valve to actually get it to go through the head

Interesting. I thought if i took the valve seals off it would drop for sure. So if i crank it to TDC for each set of springs they wont drop too far down and it won't be hard to get the new spring back on the the valve further down?

I would much rather do the TDC method than the compressed air method if it's doable.

[ssms5411]

Re: Valve Spring Replacment

just put compressed air into the spark plug hole and you will be fine...this is what I did...just make sure your air doesnt run out lol. I shouldnt...but just be mindful that you might want to hold the valve if/when your compressor kicks on...just for safe measures...even though it should still be ok.

X2 , this what we used just compressed air, no need for TDC unless you don't have a compressor, the valves will stay the same height after the new springs are on and just go back on the way they came off, its just using a different rate spring.

[OneEightSeven]

Re: Valve Spring Replacment

X2 , this what we used just compressed air, no need for TDC unless you don't have a compressor, the valves will stay the same height after the new springs are on and just go back on the way they came off, its just using a different rate spring.

What kind of compressor do you think I will need (tank and hp wise)? When talking about height, what I meant was that if I use the TDC method, won't it be harder to compress the spring back on since the valve will drop a little? I realize once the spring is locked in the height will be proper.

[cam98aro]

Re: Valve Spring Replacment

What kind of compressor do you think I will need (tank and hp wise)? When talking about height, what I meant was that if I use the TDC method, won't it be harder to compress the spring back on since the valve will drop a little? I realize once the spring is locked in the height will be proper.

the compressor you described earlier should be fine, if you are at all worried about it, you can still put the piston at tdc and use the compressor, that way you have double protection, and the volume will be a lot less.

it will be harder using the tdc method to put the spring back on, since it will drop, and you need to get it lifted up so you can put the keepers in

Interesting. I thought if i took the valve seals off it would drop for sure. So if i crank it to TDC for each set of springs they wont drop too far down and it won't be hard to get the new spring back on the the valve further down?

I would much rather do the TDC method than the compressed air method if it's doable.

this is true with cars with a lot of miles. when i took the valves off on my sbc, they all got stuck on the valve guide, so i had to get a file, and take the sligtest amount of metal off.

since our engines are interference engines, its possible for the valve to contact the piston. if it does go too far down,im sure you could just use a magnet to pull it back up

[3.4grapeofwrath]

Re: Valve Spring Replacment

If the valves drop down any amount you will have a hard time getting the keepers back on.

[OneEightSeven]

Re: Valve Spring Replacment

looks like the compressor i have is one of these cheapo ones:

http://www.harborfreight.com/air-too...sor-95275.html

Should be fine? I can also take the valve seals out without losing too much pressure right?

[ssms5411]

Re: Valve Spring Replacment

Damm a 3 gallon will work , I thought my 28 gallon was going to be a problem but i guess as long as you get the adapter in the spark plug hole good then you'll be alright. We had problems becuase of the angles and my hose was leaking so I kept on turning the compresor on. Good luck

[OneEightSeven]

Re: Valve Spring Replacment

So I've got the parts together and the tools. I'm doing the tear down now and will build up tomorrow or over the long weekend. Then get dyno'ed on Tuesday to see what kind of gains were made and to adjust the rev limiter as needed.

[OneEightSeven]

Re: Valve Spring Replacment

So.. before I ran out of light I removed the passenger side valve cover. I had to bend back the stupid engine lift bracket. I removed the rockers, bolts, pushrods and pedestal. Then I started on the drivers side and ran out of light. I got the ICM off. I am having trouble removing the driver's side lift bracket though. It seems to be loose after removing the two bolts, but it's stuck around the EGR. I can't seem to see where the EGR is connected to the bracket, but it may be because I was running out of light. I also broke a socket trying to undo one of the EGR bolts.