before bolting heads down?

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Dec 10, 2006 | 11:47 AM
  #1  
anything special I should do before bolting the heads down? Ive clean all surfaces with brake cleaner...what about the cylinder walls? leave them alone? or just wipe them clean? with anything special? oil, brake cleaner? what?

I know the gaskets go down dry..correct?




thanks
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Dec 10, 2006 | 11:54 AM
  #2  
Are you planning to run the engine soon or store it for some length of time (years)?
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Dec 10, 2006 | 12:36 PM
  #3  
I got the motor back in May or sometime and it was ready to go...since then I have broke it down to a short block and has been sitting since with me turning the engine over a few times a month..and have had it covered with trash bag....I have been gathering all my new parts to put it back together....oil pan is on....Im ready to start putting the top end on.....motor probably wont be started for an other month or so...til I get it in the car and all wired and bolted in..
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Dec 10, 2006 | 03:07 PM
  #4  
I ran a dry tap through all the head bolt holes to clean out the threads. Wire wheeled all the old head bolts to clean the threads. Cleaned and dried the mating surfaces with laquer thinner. Wiped the cylinder walls with a thin coat of motor oil. Installed the head gaskets dry. Used teflon thread goop on all the head bolt threads when putting the heads back on. Torqued them in three rounds 45, 55, 65 lbs. in the proper torque sequence.
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Dec 10, 2006 | 08:57 PM
  #5  
I'd do exactly what mnorton said.

You said you got the motor, as in used or just back from the machine shop?
If it's used, i'd take a straight edge and check the deck flatness. Since you're doing that, you can check your piston depth, since you're 80% there anyway. Nice # to have written down, and so you can figure out your SCR.
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Dec 10, 2006 | 09:30 PM
  #6  
motor is new, never ran...zero decked
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Dec 10, 2006 | 09:49 PM
  #7  
also, Put oil on the threads and the head of the bolt. Gives more accurate torque readings
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Dec 11, 2006 | 12:20 AM
  #8  
I wouldn't put any oil on the threads of the head bolts or block threads... that would probably keep the teflon goop from doing it's job. The goop will also lubricate the threads and aid in the torque accuracy issue. You may want to use some flat washers on the head bolts... Chevy did not use any from the factory, so they are not needed, but may help some. If you do use washers get some grade eight ones for sure, softer washers would not do well.
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Dec 11, 2006 | 12:49 AM
  #9  
Quote: also, Put oil on the threads and the head of the bolt. Gives more accurate torque readings
True - OEM torque specs are for oiled bolts.
For any other lubricant/sealer refer to manufacturer for recommended torque, probably less than for oiled bolts.
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Dec 11, 2006 | 03:46 AM
  #10  
Quote: True - OEM torque specs are for oiled bolts.
For any other lubricant/sealer refer to manufacturer for recommended torque, probably less than for oiled bolts.
You seem to be missing my point.

The head bolts go through into the water jacket. They need Teflon sealant on them in order to keep from leaking coolant around the bolt threads. If you oil the threads and then use Teflon sealant they may leak.

Just my two cents....
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Dec 11, 2006 | 03:52 AM
  #11  
I wouldnt trust putting the teflon sealant on them after I oiled them. As mnorton said, doesnt seam like it would seal correctly
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Dec 11, 2006 | 05:52 AM
  #12  
Quote: You seem to be missing my point.

The head bolts go through into the water jacket. They need Teflon sealant on them in order to keep from leaking coolant around the bolt threads. If you oil the threads and then use Teflon sealant they may leak.

Just my two cents....

Actually I just added to 86Camaro383's point about accurate torque readings.
Incorrect torque is one of the most common reasons for head gasket failure, especially with Torque-To-Yield bolts.

For Example:
ARP SBC Head Stud bolt Kit HSC4301
Tensile Strength 190,000 PSI
Torque with 30w Oil 85 ft lbs
Torque with ARP lube 70 ft lbs

Tell me what to edit from my previous Post so that it's clear I'm not recommending the use of motor oil when using thread sealer.
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Dec 11, 2006 | 07:24 AM
  #13  
DO NOT
Put oil, grease, or assembly lube on head bolts in a stock block!!!! They go straight into the water jacket. If you do that you WILL end up with coolant in the oil. They MUST have sealer.

Same for rocker studs in most heads: they either go into the water jacket of the intake ports. Either place, a leak past the threads is VERY BAD (you get either coolant in the oil, or oil in the intake tract).

Use the Teflon thread sealer that you can get at AutoZone or Advance (I just bought a tube of it at Adv yesterday, just to make sure it was still there) like I told somebody else a day or 2 ago that asked this question; the Teflon makes a plenty good enough lube to keep the torque specs accurate.

Small block Chevy head bolts are not torque-to-yield, so that's not an issue here.

Stock SBC head bolt torque is 60-65 ft-lbs. The torque required is a function of the clamping force required to make the gasket seal, and has little or nothing to do with the hardware or head material. The ARP instructions are not good for stock blocks, stock head bolts, stock heads, and any sort of stock gaskets; if you torque head bolts in such a setup to 70 ft-lbs, you WILL warp them, and they WILL leak, especially between the center 2 cyls on each side.

Use the Teflon thread sealer, both on the threads, and right under the head of the bolt where it bears on the casting; and torque them to 60 ft-lbs in stages, like, 35, then 50, then 60, or similar. Make sure the bolt is TURNING when you take your final torque reading (which means you'll probably actually end up slightly past 60, which is just about perfect). DO NOT exceed 65, under any circumstances. Go around the head about 3 times on every bolt after you think you've reached 60, because you will SURELY find that the first ones you tightened will be looser after you tighten the rest.
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Dec 11, 2006 | 07:59 AM
  #14  
Yeah come to think of it, Just use oil on the head of the bolt. We really dont deal much with stock blocks at the shop I work at, mostly dart and world products. But you do want to put oil on the heads of the bolts, and a teflon on the threads.
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Dec 11, 2006 | 08:10 AM
  #15  
Hey sofakingdom or anyone that knows, I'll be installing heads this winter also, I like to know if all the head bolts are going into the water jacket?
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Dec 11, 2006 | 08:46 AM
  #16  
yes they do.
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Dec 11, 2006 | 09:14 AM
  #17  
Please see above.

DO NOT

use oil, grease, or assembly lube on the head bolts, ANY PART of them. Put the thread sealer with Teflon both on the threads and under the heads of the bolts, to help them seal. The Teflon makes an excellent lube, and of course, prevents leaks, like those such as will result in coolant in your oil, if you put oil or grease or assembly lube on them anywhere.

A ft-lb or 2 of some kind of deviation in torque reading on the head bolts, is a VERY MINOR matter in comparison to antifreeze in your oil.

Details.
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Dec 11, 2006 | 12:00 PM
  #18  
Im using ARP head bolts if that matters...not stock bolts.
SO I went to NAPA and found some Permatex thread sealant with Teflon....has a big 14 on the front of the package...

SO put that all over the threads and under the head bolts? My ARP's came with a washer...and I know the beveled side goes towards the head....makes a tight fit. So with washers what do I do with the sealant? still under the head?
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Dec 11, 2006 | 12:07 PM
  #19  
Yup, and between the bolt and the washer; basically, anywhere 2 pieces of metal meet, so that you prevent coolant from getting through, and lube the surfaces at the same time.
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