Valve Work Q's

[Deener]

Hi Guys,

 

93 Loyale, non-turbo.

 

I plan on ripping a head off and doing the valves on it, in particular an exhaust valve is suspect on this head. I never taken a valve/valve stem out so I am wondering:

 

- Is there a special type of spring compressor that I need to use? Threads here mention that there is a Sears tool, but I hear it is flimsy. I don't mind spending on good tools if there's a difference.

 

- OEM only for the stem seals?

 

- Is it straightforward to compress the spring and remove the retainer clip or is there anything to be careful of/special procedures?

 

- I assume carb cleaner and some fine sandpaper will work to clean the stems up?

 

- How can I tell if I need to take it in to the machine shop for a valve grind? They gave me a $20 per cylinder quote, which seems reasonable if I need it...

 

 

Thanks in advance,

 

Dean

[NorthWet]

Not sure up in BC, but "South of the Border" you can borrow specialty tools from most Auto Parts stores. (The "borrow" is a sanctioned buy-use-return policy.) You might want to see if your local stores offer this and if they have vavlve spring compressors.

 

IIRC, there are generally 2 types: One that looks like a big "C"-clamp, and various others that are meant to mount in the valve-spring area and lever down on the spring. I have only used the big C"-clamp style.

[bison118]

some very fine emery cloth for the valve stem and be careful not to take to much off.

Edited February 25, 2011 by bison118

[El Presidente]

You should be able to take your heads to your machinist and have them pull the valves and show you whats going on and give you some input for free. It used to take me just a minute or two to pull the valves on most 4 cyl. motors.

 

The "C" clamp valve spring compressors are great, there are specific compressors for certain motors which usually lever off the cam(on OHC motors) or a rocker stud..they work great, but the "C" clamp ones can pull the valves in almost any motor.

 

I can't say 100%, but I think most of the valve stem seals we installed were Felpro, or Sealed Power. Generally, I recommend both.

 

Yes, its a straight forward head tear down procedure

 

NEVER SAND ON YOUR VALVE STEMS! This can cause accelerated wear in the valve, valve stem seal, and/or valve guide. I can't count the number of motors that customers f'd up because they didn't know what they were doing and trying to save a couple bucks. If they are varnished up and your not having the valves ground, use carb cleaner and let them soak overnight. Heavily varnished valves are a sign of worn guides or valve stems.

 

When looking at your valves, look for cracks, burns(this will look like the valve is out of round), uneven contact with the seat(1/2 to 3/4's of the valves face is shiny, the rest is dull and carbon'd up)..this could also be from a warped seat, look at the face for pitting, also look at the valve margin(there should be a small flat suface that goes around the very outside of the valve, if the seat goes straight out to the bottom of the valve, replace the valve). Check the stem tip for uneven wear and the stem itself for scoring and wear that would indicate a bent valve. Once again a machinist should be able to teardown your head and give you a quote for free or a nominal fee. They will likely also check the head face for warp, valve guides and visually inspect for cracks and other problems.

 

$20 a hole is dirt cheap and I'd be very sceptical of the quality involved. Its likely an econo job that is just a 1 angle grind and a quick trip through the parts washer. Any good shop should be able to show you the work that was done BEFORE the head goes back together and give you a warranty on parts and labor.

 

I used to be an auto machinist at ABCO machine(when they where in Sanwood WA.) and have machined more EA-81 heads than I care to mention. Our main subaru customer was Stratus Engines on Camano Island, WA.

[Deener]

Thank you so much El Presidente!

 

Thats quite the informative post. I am not worried about a couple of bucks, I really just want to know the best way to ensure quality and what to look for. The machine shop I use is called 'Heads Unlimited' and they are out of Surrey BC. The staff seems knowledable and friendly, I had a head bolt removed from my block by them for 20 bucks when my clicker wrench failed during a HG install.

 

Once I get the head off I will take a peek and if there's nothing obvious I will report on what the shop says.

 

Thanks again for the info!

 

Dean