Vortec L31 cylinder head

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(How to find good used heads)
m (Reverted edits by 50.47.172.107 (talk) to last revision by 76.228.121.182)
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* 1999-2000 Cadillac Escalade
 
* 1999-2000 Cadillac Escalade
  
==Finding Good Used Heads==
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==How to find good used heads==
 
Vortec heads have gotten a reputation for cracking easily. The truth is they do not crack any more than ANY modern lightweight production head, although there have been problems associated with leaking intake gaskets on Vortec engines that may have caused more than the usual number of cracked heads.  
 
Vortec heads have gotten a reputation for cracking easily. The truth is they do not crack any more than ANY modern lightweight production head, although there have been problems associated with leaking intake gaskets on Vortec engines that may have caused more than the usual number of cracked heads.  
  
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To find heads from an assembled engine that have a better than average chance of being uncracked, look for:
 
To find heads from an assembled engine that have a better than average chance of being uncracked, look for:
 
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*heads from a wrecked vehicle. These stand an excellent chance of being good, as long as the other things listed here pass inspection.
*Heads from a wrecked vehicle. These stand an excellent chance of being good because the vehicle was likely put in for body damage, as opposed to engine problems that could affect the performance of the head.
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*engines that do '''not''' have the thermostat removed. A missing thermostat is an indication the engine was running hot.
*Engines that still have antifreeze in them. This is a sign that the engine was likely '''not''' losing coolant, and '''not''' overheating, which could likely lead to cracked heads.
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*engines that still have antifreeze in them. Engines with straight water, or without any coolant showing, may well have been losing coolant. No one replaces leaking coolant with antifreeze- they will use straight water "until I fix it". By then, it's often too late.
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*engines with water in the oil or oil in the water. This is a sure sign of a blown head gasket or cracked casting, either of which can lead to overheating and cracked heads.
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*vehicles that do not have antifreeze receipts or antifreeze or water jugs laying around inside the vehicle. That's another sure sign there was a problem with the cooling system.
 
*Look for heads having a spark plug (or spark plugs from adjacent cylinders) with no unusually colored deposits- or a lack of deposits that were removed by coolant getting into the chamber(s). Head gaskets leaking or a cracked casting that lets coolant into the combustion chamber will make the plugs look a lot different than a normal plug- look for uniformity.
 
*Look for heads having a spark plug (or spark plugs from adjacent cylinders) with no unusually colored deposits- or a lack of deposits that were removed by coolant getting into the chamber(s). Head gaskets leaking or a cracked casting that lets coolant into the combustion chamber will make the plugs look a lot different than a normal plug- look for uniformity.
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*Look for engines that do not have evidence of stop leak in the radiator/cooling system. If it has stop leak, it was leaking. If it was leaking there's too big of a chance it overheated and cracked the heads.
 
**Signs of stop leak use is a sludgy or copper/silver colored metallic accumulation inside the radiator fill neck, the same thing under the radiator cap, and possibly even in the overflow tank.
 
**Signs of stop leak use is a sludgy or copper/silver colored metallic accumulation inside the radiator fill neck, the same thing under the radiator cap, and possibly even in the overflow tank.
  
To find heads from an assembled engine that have a better than average chance of being uncracked, avoid:
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===Online or other "sight unseen" sources===
*Engines with water in the oil or oil in the water. This is a possible sign of a blown head gasket or cracked casting, either of which can lead to overheating and cracked heads.
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'''Not recommended''' if from a private seller, especially true if shipping is involved. The cost for shipping a hundred pounds of cast iron across any distance is too high to warrant such a purchase. Very few people sells GOOD Vortec heads online. They're too easy to sell locally.
*Vehicles that do not have antifreeze receipts or antifreeze or water jugs laying around inside the vehicle. That's another sure sign there was a problem with the cooling system.
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*Engines that  have the thermostat removed. A missing thermostat is an indication the engine was running hot.
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Buying from a reputable volume/commercial seller might not be as big a risk, but research them fully and carefully before pulling the trigger. And remember, the shipping is on YOU unless otherwise stated in writing by the seller.
*Engines that have evidence of stop leak in the radiator/cooling system. If it has stop leak, it was leaking. If it was leaking there's too big of a chance it overheated and cracked the heads.
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===Local private sellers===
 
===Local private sellers===

Revision as of 20:32, 18 December 2014

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