Quote:
Originally Posted by JohnGD
Keep an eye on the rear of the engine. The cylinder head bolts can pop loose because the threads disintegrated, causing coolant leaks from a loose cylinder head, slow at first.
People say it's a design defect or metallurgical defect. Not sure. If there are slightest signs, before warranty expires, get it in for a replacement engine.
|
thats a good thing to know...do you suppose it could maybe be prevented by a retorque of the head at say every 50,000 miles? If i had the 4 cylinder engine thats what i would try, knowing what you just said...
If you want to retorque your cylinder head -
(by the way anyone who want to retorque their cylinder head be sure to read the proper sequence FIRST... it is ill-advised to just start tighening head bolts with no pattern - Certain conditions
must be met to avoid permanent cylinder head warpage.)
Remember the block i think is aluminum. i know it is on the V6, as are the heads, not certain about the 4. To prevent the threads from corroding in the first place, i'd put anti-sieze compound on the threads of the bolts. If anyone knows a good reason not to use anti-sieze on the head bolts, i dont mind being corrected, but thats what i'd do.
1-engine must be STONE COLD (this means overnight cold - engine must sit for at least 8 hours). Do not attempt to torque the cylinder head on even a slightly warm engine - it can ruin the head.
2-proper bolt tightening sequence must be used. The sequence can be found here on TN.
3-the bolts are tightened in INCREMENTS not to final torque all at once, i.e. all bolts are tightened to about 1/3 final torque, then all bolts tightened to 2/3 of final torque, then all tightened to full recommended torque. Using the proper sequence each time.
4-unless stated otherwise recommended torque setting are for clean, lightly lubed bolt threads - (lightly lubed means 2 or 3 drops of engine oil - liken i said i'd use anti-sieze, high temp variety.)
Linear Mode
