Head condition

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JohnWayne

JohnWayne

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Is there any quick way to check for valve and guide leakage? The heads are not mounted on the engine.

I do not have a flow bench.

Thanks for answer.
 
1. Compression test.

2. Leakdown test.

3. Or pull the heads, flip them over and put water or laquer thinner in the cylinders and see if any leaks through the valves...
 
^^^^ This

Oh.. and Welcome there Pilgrim !!
 
You can also use a flat plate with a rubber seal and barb fitting. Hold the plate over each port and pull a vacuum with a hand held pump, if it holds your good. Block off the exhaust crossover on the inboard exhaust ports.
 
krazykuda said:
1. Compression test.

2. Leakdown test.

3. Or pull the heads, flip them over and put water or laquer thinner in the cylinders and see if any leaks through the valves...
Click to expand...

None of that will do what he asked with the guides. He asked about valve GUIDE leakage. Only one way to check valve guides and that's to remove the springs and measure the valve guide wear with a dial indicator against the side of the valve face.
 
Here's one........Stand the head up so that the intake ports are up, carefully fill the ports with kerosine, check for leakage past the seat in the chamber, if they stay dry they are probably good to go. You could also extrapolate out that the guides are good because if they were not good, the seats would be all pounded out and they would leak. Do the exhausts the same way.

Good luck!
 
Well, he asked valve and guide.
-To that end, Burch is on the right track, but missed the obvious. If the intake ports are full of liquid it will also leak past the guides and possibly the seals.
-The liquids I wouldnt use are water and laquer thinner. Water molecules are generally too big, and tend to stick together(vis a vis the miniscus in any glass of water).And the thinner will work too well seeping through the tiniest of openings, and its highly flammable.
- The liquids I have used are Kerosene, Diesel, and common parts cleaner Varsol/mineral spirits.Diesel is stinky. Kerosene is expensive. Varsol is the cheapest and is readily available. Of these 3 Varsol is the fastest.
-Do not even mention gasoline. I will figure out a way to cyber-smack you.
In a pinch Ive used a penetrating fluid, but it too goes through practically the tiniest of cracks.
-The trick is interpreting the results. I mean if you fill all the ports, and an hour later all the fluid is on the floor, how will you know thats bad? But if an hour later only one is down, now you have a basis of comparison. And again if an hour after fill up, all are down to different levels, which ones will you condemn?You see the dilemma?
-Once the heads are on the bench, its almost too late. Almost, unless you have a standard to work against . Lets say you had a fresh head, that was expected to seal 100%. So you performed a portfill test on it, and found that 2% (just picking an abstract number) of the liquid leaked out in say 6 hours; all the same. Now you have a standard against which all other heads in your shop can be measured; namely 2%/6 hours.
-And to check the guides using this same method, the seals need to come off and the springs back on.You would have to develop your own standard, empirically.
-And thats where Rustys answer is the right answer.
-And that brings us to mderoys idea. I used that method for years to determine problems with 2-stroke engines.Itsa very good method, and simulates well what goes on in a running engine.
-If you are unable or unwilling to have a machine shop evaluate those heads, either of these methods will get results. Whether or not theyre meaningful depends on your application and interpretation.But above all Rustys statement about the guides stands. If the guides are bad, by definition so are the the valve to seat seals.
BTW, where is Korsnas?
 
An old machinist showed me a trick one time to check for worn guides remove the springs and retainers put your finger over the top of the guide and pull the valve out if it makes a pop sound the guides are in good shape if not they are worn out.

Brian
 
Finland? Can you imagine.Thats north of the 60th parallel. Here in Canada, that is nothing but a barren frozen wasteland.It has like a 3-day summer. And no roads to speak of. Yet as to land mass Id guess 1/3rd of Canada is up there.
And then theres John.Up in the high country scooting around in his 1st genA.Remarkable.
I guess winters would finally be long enough to actually get something done! Go John Go.
 
bcschief said:
An old machinist showed me a trick one time to check for worn guides remove the springs and retainers put your finger over the top of the guide and pull the valve out if it makes a pop sound the guides are in good shape if not they are worn out.

Brian
Click to expand...

BS Chief,

Old School, Quick Test ........... That Machinist was/is correct.
 
Thanks for the welcome :)

I was very pleased to find a forum about these great cars thataare so loved over the world.

I from Finland, and we got cold winters and hot summers. Many here are into old american cars. W e got or own club American Cars Route 673 with over 50 members.

Cars is fifties and sixites ans some seventies. Mostly Mopars. Many Chrysler 300:s

My other cars is ´59 Galaxie and a `59 Canadian Meteor.

But the Barracuda is the one I drive with now.
 
AJ/FormS said:
Well, he asked valve and guide.
-To that end, Burch is on the right track, but missed the obvious. If the intake ports are full of liquid it will also leak past the guides and possibly the seals.
-The liquids I wouldnt use are water and laquer thinner. Water molecules are generally too big, and tend to stick together(vis a vis the miniscus in any glass of water).And the thinner will work too well seeping through the tiniest of openings, and its highly flammable.
- The liquids I have used are Kerosene, Diesel, and common parts cleaner Varsol/mineral spirits.Diesel is stinky. Kerosene is expensive. Varsol is the cheapest and is readily available. Of these 3 Varsol is the fastest.
-Do not even mention gasoline. I will figure out a way to cyber-smack you.
In a pinch Ive used a penetrating fluid, but it too goes through practically the tiniest of cracks.
-The trick is interpreting the results. I mean if you fill all the ports, and an hour later all the fluid is on the floor, how will you know thats bad? But if an hour later only one is down, now you have a basis of comparison. And again if an hour after fill up, all are down to different levels, which ones will you condemn?You see the dilemma?
-Once the heads are on the bench, its almost too late. Almost, unless you have a standard to work against . Lets say you had a fresh head, that was expected to seal 100%. So you performed a portfill test on it, and found that 2% (just picking an abstract number) of the liquid leaked out in say 6 hours; all the same. Now you have a standard against which all other heads in your shop can be measured; namely 2%/6 hours.
-And to check the guides using this same method, the seals need to come off and the springs back on.You would have to develop your own standard, empirically.
-And thats where Rustys answer is the right answer.
-And that brings us to mderoys idea. I used that method for years to determine problems with 2-stroke engines.Itsa very good method, and simulates well what goes on in a running engine.
-If you are unable or unwilling to have a machine shop evaluate those heads, either of these methods will get results. Whether or not theyre meaningful depends on your application and interpretation.But above all Rustys statement about the guides stands. If the guides are bad, by definition so are the the valve to seat seals.
BTW, where is Korsnas?
Click to expand...



You got to cyber smack me, because I tried with gasoline. And in one chamber the fluid sank. So I guess is the valve there.
 
AJ/FormS said:
Johnny, Johnny.
What can I say? I know. So glad you read the post. You got away with it this time!
Sorry about the leaky valve.Looking forward to seeing some pics.
Click to expand...

I have found some 318 heads with casting number 714. Those would be similar to 302 castings. I think they would work fine on my 273.
 
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