Valve seal replacement on 82

Stoney#1

Stoney#1

Stoney
My 82 X with only 44,000 miles gives out an awful lot of smoke on start up after sitting for a while.
I am thinking that the valve seals may be shot and am looking for advise on how hard it is to replace these. Can it be done with the motor in car or is it better to remove it? Are there any special tools I would need to do this? So many questions!

Thanks

Stoney
 
The valves seals themselves are very reasonable, Midwest Bayless has them.
http://www.midwest-bayless.com/Fiat...set-8mm-rubber-fiat-lancia-dohc-sohc-new.aspx
http://www.midwest-bayless.com/Fiat...set-8mm-teflon-fiat-lancia-dohc-sohc-new.aspx

Since the X has a true overhead cam engine, the cam box has to come off. That means you'll need other parts: cam box to head gasket, cam box cover gasket, and since the timing belt will be involved, this is a good time to replace it and the tensioner bearing. If the seal at the cog end of the cambox is weeping, with the cam box off, it would be easy to pull the cam out of the cam box and replace that seal.

When removing and installing (esp installing!) the cam box, it's a pain to keep the followers/buckets in place. I use small super duper neodymium magnets between the cam lobes and the bucket tops to hold them in place.

Valve clearances may change after removing and replacing the cam box, so be sure to check 'em after the cam box and belt are back on, but before you button up the cam cover and the throttle linkage.

To do the valve seals with the head still in situ, you will need a valve spring compressor tool---not the big C-shaped one for when the head is off, you need one that acts only on the springs themselves. Examples:
https://www.jbtoolsales.com/otc-4573-universal-overhead-valve-spring-compressor
https://www.ebay.com/itm/HD-Overhea...Engine-Seal-Keeper-Replace-Tool-/292159587076

One more thing that will help a lot is shop air and an air adapter that pressurizes the combustion chamber thru the spark plug hole. That will help keep the valve head pressed up against the seat and make it easier to install the new valve seals. Like this: http://www.jegs.com/i/JEGS-Performance-Products/555/80522/10002/-1 The old "rope fed into the spark plug hole" can work too, as you are not putting a lot of force onto the valve stem when pushing the seals on.

Before you buy any tools, drop in at a local big box auto parts store and ask if they have something similar for loan.
 
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You can use rope fed in the spark plug hole and bring up the piston until it stops instead of compressed air to hold the valves in place; do one cylinder at a time.

Edit- sorry Dan, didn't read all the way thru your post, didn't mean to repeat
 
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I have never done this, but Gildo did this on my X1/9. He used compressed air to raise the valves on the engine and change the seals. He is a true Fiat mechanic. This took him less than 2 hours and only removed the valve cover. This was after I did the head gasket and installed the valves seals poorly.
Anyone have instructions to this trick?
 
I'd like to see how he got access to the valve stems/springs with the cam and buckets in place.
I have to agree with Dan, the cam tower needs to come off too.
 
Thanks for the directions everyone. With this low mileage would I have to be worried about the valve guides being worn?

Thanks

Stoney
 
Before attempting anything, be sure you correctly adress the problem. Valve seals are a probability, but if I'm right, a bad head gasket, allowing prestone to find it's way into the oïl could also be the cause.
 
Daniel Forest said:
Before attempting anything, be sure you correctly adress the problem. Valve seals are a probability, but if I'm right, a bad head gasket, allowing prestone to find it's way into the oïl could also be the cause.
Click to expand...
If it were that, wouldn't the oil appear milky? My oil is nice and clean, although there is only about 500 miles on it.
 
Perhaps Daniel meant to say a head gasket leak allowing coolant into a combustion chamber, causing steam out of the exhaust? You can differentiate the two by the appearance of the smoke, blueish or whitish color.
 
Dr.Jeff said:
Perhaps Daniel meant to say a head gasket leak allowing coolant into a combustion chamber, causing steam out of the exhaust? You can differentiate the two by the appearance of the smoke, blueish or whitish color.
Click to expand...
That is a problem! I see it as whitish and my grandson sees it as Blueish
 
Stoney#1 said:
If it were that, wouldn't the oil appear milky? My oil is nice and clean, although there is only about 500 miles on it.
Click to expand...

Stoney#1 said:
Thanks for the directions everyone. With this low mileage would I have to be worried about the valve guides being worn?

Thanks

Stoney
Click to expand...

Most likely not. You will be able to try to wiggle each valve after you remove the springs. If you don't have a frame of reference you really won't be able to tell if they are worn or not just by wiggling, and to measure you'd need to remove the valves which means removing the head. The specs for valve stem to guide clearance are 0.0012 to 0.0026 in.
 
Perhaps before tearing anything apart you should do a compression test and leak-down test. If it is a head-gasket or other problem that should show it. I like to know what I'm chasing before I go after it. :)
 
Actually to do compression and leak-down tests you won't even need that fitting. Go to your local 'big-box' parts store and get the 'loaner' sets for both tests. They will include everything you need to check out whats going on inside the engine. Best to do this first.
 
Like Dr. Jeff says above. I was delayed in posting this.

While you are at it... A leak down tester (One was listed at the bottom of the same Jegs page) will allow you to carefully check for leakage in intake and exhaust valves and the rings. If you get a higher rate of leak down, you can listen at the intake, exhaust, and oil breather, and if you are lucky get an indication of where the problem lies. High leak down on two pistons next to each other can indicate a gasket burn through.

I am sure those who have done this many times can give you much more detail on the diagnostics of the test.

Paul
 
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