Valve seals for camel hump heads?

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ChuckN

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I pulled my plugs to check the color, and I noticed the dreaded oil on the threads. The outside of the heads below the valve cover gaskets are dry.

It does not visibly smoke from the tailpipe. One plug looked a little black, but not coked up with oil. The rest were normal.

Engine has less than 2000 miles on it, purchased already rebuilt and in the truck. Or, at least it looked clean internally, and could see crosshatches in the cylinder bores and .030 stamped in the pistons with my scope.

I plan to do a compression check but unless whatever shop made a mistake, it’s unlikely that it would be rings.

I have no problem redoing the valve seals but apparently camel hump heads used an o-ring and it sounds like they can be less than reliable or problematic.

I don’t want to get the cart before the horse, but if I do end up replacing seals, what would be the best style or brand? Apparently some of the new style seals require machining, and I’m not taking off the heads. Any input is always welcome.

Thanks,
Chad
 

ChuckN

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Go to Oreillys,ask for valve seals pioneer OS-450 umbrella seals .
Sounds like a plan. Those don’t need any mods or machining? Sorry, there’s just a lot of information floating around out there. I need to find a good video to watch. Actually, I’m going to make an effort to find one today that explains it all. It’s not rocket science, I’ve just never had to mess with them.
 

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@Ricko1966 looks like those might be on their way out. Only some various smaller websites offer them, O’Reillys says unavailable.

Of the websites they are listed, they are listed as both .530 and .610. Do you know which one is right? Thanks.
 

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@Ricko1966 looks like those might be on their way out. Only some various smaller websites offer them, O’Reillys says unavailable.

Of the websites they are listed, they are listed as both .530 and .610. Do you know which one is right? Thanks.
I do not know for positive, my brain is saying .530
 

ChuckN

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Well @Ricko1966 I tried to get a camera in there to see if I could see any hint of a seal but the only thing I accomplished was verifying that I had dual springs. I’m assuming those would not be stock.
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I’m planning on getting a valve spring compressor (I already have an air compressor fitting to keep the cylinder pressurized) and then I’ll take a spring off and see if I can measure the diameter of the boss. Apparently sometimes they get machined to fit whatever they seal they want to use.

If this all falls apart, it’s ok…I’d rather have a head with screw in studs anyway.
 

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Chuck,what you may want to do is roll the piston down in the bore a bit then feed as much of an old plug wire with 1 end cut off as you can into the cylinder. Then rotate the engine to compress the plug wire and hold the valves. This way you aren't committed to fixing it while you are pressurizing the cylinder. You can get things apart,measure,contemplate,order parts,what ever. Then come back and finish.
 

ChuckN

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Chuck,what you may want to do is roll the piston down in the bore a bit then feed as much of an old plug wire with 1 end cut off as you can into the cylinder. Then rotate the engine to compress the plug wire and hold the valves. This way you aren't committed to fixing it while you are pressurizing the cylinder. You can get things apart,measure,contemplate,order parts,what ever. Then come back and finish.
That’s a good idea. I like that better than a flimsy rope.

On second glance, those are just damper springs, I don’t think they’re true dual. Do stock heads usually come with damper springs? I’ve never looked closely, honestly. Lashed lots of valves, never looked close.
 

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I hate using fode parts but I heard some of there's fit like maybe 302 seals can't remember fir certain
 

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I found some of the Pioneer valve seals OS-450 that @Ricko1966 suggested on eBay in the stock size for cheap, they’re getting harder to come by so I ordered them up for 17 bucks and free shipping. I figured if they’re the wrong size, I’m out less than the cost of 5 gallons of gas.

They kind of have an interesting history. All the early camel hump heads used an o-ring instead of an umbrella. But, the somewhat polarizing Avanti (that used the 327 SBC) had umbrella seals designed for it, and it was the Pioneer part- or that’s at least the Pioneer is designed off of. But good luck finding the source for that info- I went down the rabbit hole yesterday since I’m down with a bug.

I think this morning I’m going find a spring compressor and see what lurks beneath, and then while I’m at it take the spring down to the local machine shop and see if they can measure the pressure- no sense putting them back on if they’re stock. And I have a sinking feeling they are.

Edit- I’m going to take a little time and do a compression test on all cylinders first before I take it apart.
 

Ricko1966

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I hate using fode parts but I heard some of there's fit like maybe 302 seals can't remember fir certain
You can use 289,302 umbrella seals,but they are large enough diameter they sometimes get wadded up in the dampers
 
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ChuckN

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Have the heads ever had a valve job? It the guides are worn new seals might only be a temporary fix and a valve job will be in the future.
That’s a wonderful question. I bought the truck with a rebuilt 327/350hp just put in it with nothing hooked up.
Except it’s not a 327, block says 350. So I asked the guy I bought it from about that and he came clean that he didn’t rebuild it, that it was purchased already rebuilt.

So at this point all bets are off. The lower end was rebuilt- a scope revealed fresh crosshatches in the cylinders and a .030 stamped in the piston. But as far as the heads, they could’ve been slapped on there with just fresh orange paint. I have somewhat low expectations at this point because a lot of things he said it was, it isn’t. And he himself had no actual clue as to what he’d bought.
 

ChuckN

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Have the heads ever had a valve job? It the guides are worn new seals might only be a temporary fix and a valve job will be in the future.
But more to your point- if they start looking pretty suspect, I have no problem dipping into my savings and getting a set of budget line AFR heads for it. One thing I’m going to do is when I have the rockers off, put a straight edge along the top of the valves and see if they’re pretty even- if not, I’ll know I have sunken seats.
 

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