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air bubbles around spark plug & lifting bolt

Posted: Fri May 17, 2019 7:33 am
by Lakesailor
what’s the best remedy to stop air bubbles from around 2 spark plugs and the bolt that
used when lifting the engine out of the car ? is it as simple as teflon tape ? Or is their a
special “pipe dope” ? BTW, we assume this is a major cause of the engine running rough.
Thanks for input/suggestions !

Re: air bubbles around spark plug & lifting bolt

Posted: Fri May 17, 2019 9:46 am
by John.Zibell

Re: air bubbles around spark plug & lifting bolt

Posted: Fri May 17, 2019 10:00 am
by DanTreace
The fixes for weeping around the pipe threaded spark plugs is thin alum foil, or some can get by with thread ant-seize too. But if the threads in the cyl. head are compromised by rust pitting, or just broken, another cyl. head in better shape is nice.

As for that 'center bolt with stud sticking up' in your photo, that isn't for lifting the motor. Appears a block hole for the bolt is compromised, and someone placed a stud there, and a hex nut on top. That could be your source of leak, that crude fix may have cut loose.

IMO, Best to pull the head, clean, inspect, and use thread inserts if needed, to correct all the block head bolt holes. Then a better cyl. head, and proper set of new head bolts. Yours has an assortment of various bolts holding the cyl. head now.

Re: air bubbles around spark plug & lifting bolt

Posted: Fri May 17, 2019 10:09 am
by DanTreace
BYW, the bolts down the center of the block (#1, 2, 3, 4, 5) holding the cyl. head are the most important to have tight, the space between the cylinders is slim.

The gasket is thinnest at this point. Proper cyl. bolt tightening sequence is to pull those center bolts down first, to squish the new gasket, getting best seal. Then alternate the other head bolts to have best sealing of the head to the block.



Typical spot the gasket goes, at these places.
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