GM Base marine 502 Valve question.
#11
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Actually the exhaust valve that is in those heads (1800runsnew) and in the Merc black engines ( 454/502 Mag) is a 2 piece valve. It is welded in the middle of the stem. It has a stainless stem and an Inconel head. Next time you have one out of the head, put a magnet to it. Inconel is not magnetic and the stainless is. If you run the magnet up the stem starting at the head, all of a sudden it will stick to the stem.
Eddie
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Eddie
Last edited by Young Performance; 10-27-2009 at 12:04 AM.
#13
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I found it purely accidental. Those valves are susceptable to breaking at the weld, so I started looking at one to try to figure out what it is made from and why they broke in the same spot. I had a magnet on the workbench one day and it stuck to the valve stem. I was playing around a little later and realized it wouldn't stick to the head. Then I figured out that it is a two piece. It is crazy that you can not tell where it is welded without the magnet. There is absolutely no line what so ever. Whoever does it does a fantastic job. It is actually a good money saver. If they could figure out how to make it stronger, it would be a great alternative to the expensive, heavy Inconel valves. There is no need to have an Inconel stem....only the head. I'm sure they save a small fortune on the valves by doing it this way since the Inconel is over twice the cost of the SS.
Eddie
Eddie
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Can u tell me more about this?? It the oiling system routed differently or what?? thanks. I wish there was a How too for 454 to 502 swaps, i thought everything was just a swap over.
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Dont run the engine untill you have the right bypass valve or you will be removing the engine due to you buring it up like a lot of other guys have done. I spent a lot of research on my set up with the right bypass valve install I'm only running a filter on the block and I'm motioring the oil temp then going from there run a good filter like napa 1061 wix do not run fram they are junk.
Do a search here on bypass valves if you would like to talk to me about the whole set up give me a call @ 734 383-0730 ask for Dale
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Back to the valves.
I just took a valve out of a head and the magnet only stuck on the TIP. Do you need a super strong magnet? I just used a telescopic one used to things you drop in hard to get places.
Yes I did check out the website. The prices seems to good to be true. I am in the market for two.
I just took a valve out of a head and the magnet only stuck on the TIP. Do you need a super strong magnet? I just used a telescopic one used to things you drop in hard to get places.
Yes I did check out the website. The prices seems to good to be true. I am in the market for two.
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Back to the valves.
I just took a valve out of a head and the magnet only stuck on the TIP. Do you need a super strong magnet? I just used a telescopic one used to things you drop in hard to get places.
Yes I did check out the website. The prices seems to good to be true. I am in the market for two.
I just took a valve out of a head and the magnet only stuck on the TIP. Do you need a super strong magnet? I just used a telescopic one used to things you drop in hard to get places.
Yes I did check out the website. The prices seems to good to be true. I am in the market for two.