I've been having problems with my valves since last August. The seals need to be replaced and the valves adjusted. I dont have the tools to do it with the heads on the car. I was talking to a mechanic this morning and he thinks that I need to have the heads serviced. He's a very good mechanic so I trust his opinion. He said that when Chevy 350's with over 110K miles on them (like mine) start burning oil on startup it usually means worn valve guides as well as the seals. He quoted me $450 to replace just the seals.

So this is where I come to the forum to ask for your input. Where do I go from here? I dont have a ton of money to pay someone else to do the work. Would I be better off just buying a new set of heads?

 

Non roller rocker arms can put extra wear on the valve guides. To replace them you would need the heads off.

Get a quote from your machine shop to disassemble, tank, mill, replace valve guides seals, etc. and then compair it to the cost of a new set of assembled better flowing heads, see if you want to pay the difference.

For me, if you have the money available, I would buy a better flowing set of heads, with better hardware already assembled

 

Is $450 including R/R the heads?

 

Keep in mind that when you freshen the heads you "MAY" experience blowby from tired rings in a 110K engine.

 

I can't imagine a mechanic is pulling the heads for $450.00. Or that he would remove them to replace the seals.

I would pull the heads, myself and take them to a machine shop for inspection and an estimate. Then you can make an informed decision on whether to replace or repair.

 

$450 is ridiculously high if he's not. Which is why I asked.

 

What special tools do you need. All you need is a small valve spring compressor. I bought the kind with the star shaped wheel on top for about $12. A piece of nylon rope held up my valves.

 

The main tool you will need is the GM Shop Manual for your '85 Vette.

I used nylon rope to hold up the valves, the three bolts from a damper puller kit to help manually rotate the crank, a screwdriver into the sparkplug hole to detect when the piston was near TDC (watched the valves to know it was on compression stroke), a magnetic wand to remove the keepers and a on-spring valve spring compressor. Total tools cost should run <$100.

Since your '85 has different exh seals from intake, I would get all the seals from your local GM dealer. Also pick up a set of new forged keepers to avoid a dropped valve later.

With the shop manual as a guide you can easily do the job in a weekend or less.

 

As far as tools go I have 2 types of valve spring compressors, one thats a bar and one that you have to take the heads off to use. I dont have a reliable source of compressed air (old leaky air compressor) and even then if the valve guides are worn it might not hold.

I didnt ask if that was $450 to remove the heads or not, but its too much either way in my opinion. That doesnt include any R&R either.

I talked to a good friend of mine who builds engines and he said he'd sell me a set of aluminum heads off a 283 for really cheap. I figured I could take those to a machine shop and fix them up so I can keep driving the car.

 

what you need to remember is that your car has overdrive.
Probably .6 : 1. that means the engine rotates 40 % less than it would without overdrive.
A regular 70's car without overdrive would be eaten up with road miles.
your engine has about 65,000 miles, and all it needs is valve seals.
remember also, your engine gets very hot because it;'s a smog motor with a 185 thermostat, and runs anywhere between 180 to 225 degrees.
The factory valve seals are little neoprene o rings that fit on the valves.
they get hard and fail to shrink onto the valve stem and prevent the oil from sliding down the intake valves when the engine is cold, or at slow speed such as idling.
The oil burns, and leaves deposits on the valve, and the combustion area, and that's why you need to take care of this problem.
The best way to do it is to fill the cylinder with compressed air through the spark plug hole, and use a spring compressor to squeeze the valve spring so you can get the keepers off and pull the spring retainers to get at those pesky little o rings.
Once you have gotten them off, and put everything back, you need to readjust the valves.
All that is, is turning the nut on the rocker 1/2 turn after the rocker stops clacking on the top of the valve as you continue to turn the nut.
You need to first count the turns on each rocker stud when you remove the rocker nuts. then return the nut to that number of turns.
get a piece of paper, and write down how many turns so u dont screw up.
When you start up the car, don't wear a good shirt.
The pushrods spit oil at you as you are turning the nuts.
So get the engine running, then at the first valve, undo the nut till the rocker clacks on the valve. Then turn it back in till the clacking stops.
Then tighten the nut slowly 1/4 turn, wait till the engine stabilizes, and turn it another 1/4 turn slowly...do them all.
You can do one side at a time, so keep the rocker cover on the side you are not working with.
That is all, except change the rocker cover gaskets when you put the covers back on.
simple---simple.......
The hard part is what you have to take off to get the covers off.