Stripped manifold bolt holes

[ikle]

When I was torquing the five bolts that hold the plenum to the intake manifold, two of them stripped out the holes and I did a search and it seems fairly common when using a RJC power plate. The fix is to Helicoil them but was wondering if using thread inserts would be a better option. Thanks for your reply, Kyle.


http://www.fastenal.com/web/product...RjysYNLNJn2yQQgy8bc9z1rz!423933937!-799979082

 

[pacecarta]

there is thread left to grab ...just measure and get longer bolts ..M8x 1.25

and the correct way to fix is helicoil but you shouldnt need that

torque is only 12 ft lbs so take it easy next time

 

[coach]

Take the plenum off...put a rag in the opening and drill out every thread and install a Heli coil. You'll be way better off in the long run. There aren't that many threads in there. I drilled out every hole on my intake and re tapped with a coil. Alum threads suck...
Your not going to have room to tap that out to 12mm. Use the Heli coils.


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[Squid4life]

X1,000,000. Coach is correct. Get it over with now and forget about it.


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[ikle]

What do you think about these, seems like a great thread repair system. Is there enough meat on the manifold to use them ? Thanks for your help, Kyle.

http://www.mechanicstoolsandbits.co...812-125mm-metric-thread-repair-kit-p-140.html

 

[mtocrs1]

Seem pricey compared to a Heli coil set

 

[pacecarta]

why keep looking for another way .. helicoil and done
http://compare.ebay.com/like/110791689269?var=lv&ltyp=AllFixedPriceItemTypes&var=sbar

 

[ikle]

why keep looking for another way .. helicoil and done
http://compare.ebay.com/like/110791689269?var=lv&ltyp=AllFixedPriceItemTypes&var=sbar

I am not looking the other way, I am looking to see if there is a better way. I agree that a Helicoil would work and I have no problems using it. But I have read that a Time-Sert (carbon steel sleeve) is way stronger than the Helicoil (stainless steel coil). I only plan on doing this once and figured carbon steel would out last stainless steel in the long run.

Has anyone have any experiance with the Time-Serts, I have heard nothing but good things about them. Thanks again, Kyle.

 

[ikle]

Seem pricey compared to a Heli coil set

I know, but if they last forever its cheaper than buying a manifold.

 

[coach]

I am not looking the other way, I am looking to see if there is a better way. I agree that a Helicoil would work and I have no problems using it. But I have read that a Time-Sert (carbon steel sleeve) is way stronger than the Helicoil (stainless steel coil). I only plan on doing this once and figured carbon steel would out last stainless steel in the long run.

Has anyone have any experiance with the Time-Serts, I have heard nothing but good things about them. Thanks again, Kyle.

Ok...I'm not asking to be a smart ass, but...How in the hell do you figure that carbon steel is going to outlast stainless steel? Carbon steel reacts with alum. They do not like each other. STAINLESS LASTS FOREVER!!!
Next is this...Your not going to strip out a Heli coil unless your a total idiot. Tighten to 12-15 ft lbs MAX!!!
Champion Racing Heads uses Heli coils to hold the rocker shafts in their aluminum heads...if you think that your plenum is going to have more force on it then rocker shafts, then just weld the plenum onto the intake and be done with it.
I've been engineering for almost 25 years...don't make it harder then it needs to be.


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[ikle]

Ok...I'm not asking to be a smart ass, but...How in the hell do you figure that carbon steel is going to outlast stainless steel? Carbon steel reacts with alum. They do not like each other. STAINLESS LASTS FOREVER!!!
Next is this...Your not going to strip out a Heli coil unless your a total idiot. Tighten to 12-15 ft lbs MAX!!!
Champion Racing Heads uses Heli coils to hold the rocker shafts in their aluminum heads...if you think that your plenum is going to have more force on it then rocker shafts, then just weld the plenum onto the intake and be done with it.
I've been engineering for almost 25 years...don't make it harder then it needs to be.


Posted from the TurboBuick.Com mobile app

Coach, thank for the info, I wasn't doubting anyone . I was just looking into all my options, that's why I post on here. I am a class A auto body collision tech for 27 years , years ago the proper repair procedure for replacing a non-structural panels was to mig weld (old tech), now its "weld bond" (new tech). Just about everything advances with new tech, I was just inquiring if there was any new tech before I go ahead with the preferred old school tech. I also didn't know that carbon steel reacts to aluminum. Every day is a learning experience. Thanks again for your reply, Kyle.

 

[pacecarta]

in the end the simplest fix is just get longer bolts or studs run to the bottom as there are still plenty of threads left

helicoil or not you still need longer bolts

 

[coach]

in the end the simplest fix is just get longer bolts or studs run to the bottom as there are still plenty of threads left

helicoil or not you still need longer bolts

Pacecar is correct...longer bolts are needed. A stud may work too as you probably only stripped 2 or 3 threads out. I did not want to ever have the issue again, so I drilled them all...even the fuel rail mounts. They are all the same depth and thread size.

 

[DOUGGN]

Coach, thank for the info, I wasn't doubting anyone . I was just looking into all my options, that's why I post on here. I am a class A auto body collision tech for 27 years , years ago the proper repair procedure for replacing a non-structural panels was to mig weld (old tech), now its "weld bond" (new tech). Just about everything advances with new tech, I was just inquiring if there was any new tech before I go ahead with the preferred old school tech. I also didn't know that carbon steel reacts to aluminum. Every day is a learning experience. Thanks again for your reply, Kyle.

The aircraft industry uses helicoils in aluminum all the time - it will work great in a Buick as well.

 

[aminga]

And don't forget to locktite the helicoils in

 

[coach]

And don't forget to locktite the helicoils in

Not really necessary. They are not going anywhere. If you do...let the locktite dry before installing the bolt. If the bolt gets locked in...it will screw up the coil trying to get it out. Thats why I stay away from adding locktite.

 

[earlbrown]

Locktiting before the bolt goes in doesn't sound like a good idea either. Doing that would have locktite in certain areas while the coil is in an unloaded state. Part of the reason helicoils work so well is because the load makes the coils push outward rather than just trying to rip the stock threads upwards out of the hole.

Then again, helicoiling a hole is one of those times I really don't have to use my brain. In real life it probably won't matter at all. Either solution is better than not having any threads at all. lol

 

[aminga]

Locktiting before the bolt goes in doesn't sound like a good idea either. Doing that would have locktite in certain areas while the coil is in an unloaded state. Part of the reason helicoils work so well is because the load makes the coils push outward rather than just trying to rip the stock threads upwards out of the hole.

Then again, helicoiling a hole is one of those times I really don't have to use my brain. In real life it probably won't matter at all. Either solution is better than not having any threads at all. lol

I've had helicoils back out. particularly in shallow holes like the valve cover bolts.

 

[chopped39]

There is not enough safe room for a time sert on a stock manifold. If you drill the manifold and then bore the hole its going to weaken the manifold.Then when you screw insert in it might bust the bung off the manifold. Heli coil is the way to go. I never had a heli coil back out on me.I sure the less area they have to bite the less they are going hold.

 

[ikle]

Thanks for all the advise, I will be getting her done soon, so I will check in to post my results. I see that Helicoil makes a long, medium and short coils, which would be the preferrence for what I am doing. I would think the long would be better but want to make sure. Thanks again for all your help, Kyle.