Time sert head stud problems

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Mcwho
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Time sert head stud problems

Post by Mcwho »

What started as a air leak on a cockeyed head on cyl #2 has grown. We found heli coils, pulled them and installed the time sert inserts on left side. During torquing several of the time serts pulled out. We have found a kit for time serts for harley qhich are oversize. Looking at those at this point.

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1965 Corvair Monza Coupe 110, 4 speed, Liberty Blue

66vairguy
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Re: Time sert head stud problems

Post by 66vairguy »

Sorry to hear you had problems. Did you use the "special" length Time Serts from Ray Sedman? The standard Time Serts are too short.

In some areas of the block the bigger diameter inserts won't work - not enough case material.

Ray's site -- http://www.american-pi.com/corvair/corvhome.html
He doesn't list everything he sells, and he's a part time vendor so sometimes he's hard to reach.

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Mcwho
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Re: Time sert head stud problems

Post by Mcwho »

I used the special ones from clarks, they sre 7/8 long.

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66vairguy
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Re: Time sert head stud problems

Post by 66vairguy »

You may know this already - but now the consensus is for a maximum head nut torque is 30 ft. lbs. (clean dry threads). Over the years the GM specification changed from 32 ft. lbs up to 40 ft. lbs. Now those numbers are considered factory first time assembly numbers and are excessive for re-assembly.

The only issue with the 30 ft. lbs. number is you should re-torque to 30 ft. lbs. a second time, usually after a day of sitting to allow for gasket compression.

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acarlson
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Re: Time sert head stud problems

Post by acarlson »

There is an interesting comment from a member on the other forum regarding this problem. I've copied it below:
Re: Ugh. Insert Failure Bad
Posted by: 66vairman ()
Date: August 19, 2020 05:00PM

I see one problem. The insert is a solid steel unit, possibly a Time Sert.

Notice the head stud, about four thread are showing and those are the four "special" threads that lock the stud into the aluminum case. The valley of the thread is not as deep as a standard thread for that pitch. The Time Sert, or a steel insert and will not give much.

The head stud "special threads" must be cut with a quality machine die (that stud is tough) so it screws easily into the Time Sert. Otherwise you end up using excess force trying to get the stud threaded in all the way and possibly distort the Time Sert. Either way, the aluminum looses the battle.
Alec Carlson
Dahlonega, GA
1965 Regal Red Corsa 4 Speed Turbo Convertible
Restoration "In Progress"...

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Mcwho
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Re: Time sert head stud problems

Post by Mcwho »

I appreciate the quote from the other forum, but im still at a loss after reading this conjecture about time serts or other steel inserts. I have no idea what WILL hold. I am not a machinist but have told one solution is to fill the stud holes and retap them.

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joelsplace
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Re: Time sert head stud problems

Post by joelsplace »

A Timesert should have no problem holding. Are you sure your torque wrench is accurate?
113 Corvairs, 5 Ultravans and counting
Northlake, TX

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Mcwho
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Re: Time sert head stud problems

Post by Mcwho »

Its a professjonal digital wrench my mechanic has.

Btw

The special head studs came w a note that said use 10 to 30 foot lbs. Will something like 10 or 15 be enough?

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Mcwho
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Re: Time sert head stud problems

Post by Mcwho »

To acarlson:
What is the other forum?

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joelsplace
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Re: Time sert head stud problems

Post by joelsplace »

No. Some people use 25 with good results.

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acarlson
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Re: Time sert head stud problems

Post by acarlson »

Mcwho wrote:
Fri Aug 21, 2020 8:27 pm
To acarlson:
What is the other forum?
http://corvaircenter.com/phorum/list.php?1
.
.
Alec Carlson
Dahlonega, GA
1965 Regal Red Corsa 4 Speed Turbo Convertible
Restoration "In Progress"...

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Mcwho
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Re: Time sert head stud problems

Post by Mcwho »

Ok, im game ill check the torque wr torque against another one.

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Mcwho
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Re: Time sert head stud problems

Post by Mcwho »

Ok my torque wrench is a craftsman / my mechanic has a digital one. Possay a snO on. Will check later today.when mine reads 30 ft lbs, his reads 23. I have removed the heli coils the prev owner installed. Instelled time certs from claRks. There is some incorrect info as to whick studs to use but most pulled out. Went ro a "big sert" they havent pulled out yes as we havent torqued them yet. Am worried about ybe different in torq Nd dont want them to pull out as well. They are about 1/8inch wider ( at abt 1/2 " diameter) the the clarks time serts.

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61SuperMonza
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Re: Time sert head stud problems

Post by 61SuperMonza »

If you are concerned that the time sets won't hold use a less aggressive torque sequence. In other words when you get to 15 pound feet of torque bring the additional 15lbs. In 2.5 lbs. Increments until you have 30lbs of torque on the heads. You have to go for it either way. Good luck.
First corvair in 1985
Have owned 4 corvairs since
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66 Monza coupe 110 PG
66 Monza coupe 140 PG
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terribleted
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Re: Time sert head stud problems

Post by terribleted »

You seem to be having continuing issues with studs and inserts pulling out of the block. My suggestion is to purchase a different block to use. The one you have may have been severely overheated and has lost it's heat treating making it soft. In any case I would not want use a block that has this type issue. Why was the head cockeyed? Machined incorrectly? What is the state of the engine? I am assuming that if you are drilling and installing multiple inserts that the engine is apart (do not see how you could really clean up the chips with it assembled) and if it is this is the time to swap blocks.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
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66vairguy
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Re: Time sert head stud problems

Post by 66vairguy »

O.K. I think there area a couple of issues - you said "helicoils were removed and TimeSerts installed". Most inserts require drilling out the "original" stripped hole. So after removing the helicoil you may not have enough material for a proper Timesert install. NOTE: In some areas of the block I doubt there is enough material for oversized inserts. A TTed said - you may have to get another block.

The issue with different torque wrench values needs to be solved. A fellow in our club stripped out and broke bolts because his torque wrench was WAY OFF. Why? He had a clicker type and left the selector at a high torque value when he finished using it and THAT RUINS THE CALIBRATION. You should never leave a clicker type set to a torque setting for more that the time to use it THEN ALWAYS BACK TO ZERO!

The old beam type torque wrenches tend to be stable and I use one to verify my "clicker" or electronic torque wrench. In aerospace torque wrenches are routinely sent out for calibration/verification.

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