Stripped Holes in Cylinder Head for Intake Manifold Bolts

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why is that more difficult? It's an easy fix if you are careful and a magnetic pickup can reach in and get it if you drop it. the lifter bores and cam keep it from falling anywhere suspect. I've seen it done many times in a pinch. In the early aluminum head days with Bob Glidden and other pro stock racers such a repair was commonplace. Its just an air pump. None of these engines that we run are some kind of special thing. you can put 30 grand into an engine for your car and still not have the quality of a hospital generator engine. wake up
 
I echo the sentiments of those saying take it to a machine shop. A good one.
 
If you still have the intake off, lay some aluminum foil under each of the holes coated with wheel bearing grease while "SLOWLY" drilling the holes. Discard the foil carefully keeping the shards in the grease. Use a pencil magnet to pick up any possible escapees. Put down more aluminum foil and then coat the tap with grease, which will keep most, if not all of the shards in the tap. Again use the pencil magnet to make sure the are none left. Put some heavy shop rags under the holes and rinse the holes lightly with a solvent. Put RED Loctite on the Helicoils and slowly screw the in. Let the Loctite cure for at least 3 hours before reinstalling the intake. I know this is very time consuming, but it works. I've done it many times on cast iron and aluminum heads with great success. As I said, use the pencil magnet all around the area many, many times just in case a shard or two escaped.
 
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they are Not at a right angle to the surface. Thanks Volaredon and Badlittlered. I measured them about 8 degrees so probably between 7 and 9 degrees is correct, but I do not know the theoretical correct angle.
 
Most people don't realize that the major diameter of a thread is very close to the minor diameter of the next size. So where 3/8" threads are totally stripped the hole is now very close to the drill diameter req'd for a 7/16" tap.
While this is true, why would anyone want to mix and match on an area where there is limited space for screws in the first place cause of the intake runners when you can repair the threads stronger than they originally were to begin with with helicoils? Once you helicoil a hole, the insert is not coming out or become loose.
 
Metric anything is for foreign cars. Foreign car mechanics at dealerships are the highest paid mechanics because working on foreign cars sucks. Metric fasteners are not the only one of their stupid ideas. It’s a criminal shame that their stupid ideas have overcome American automotive manufacturing. Cars used to be rebuildable, now they are just disposable appliances. They used to have style and class, now they look like colored jellybeans. And 95 % of the mechanics out there don’t know how to fix anything, they just know how to replace parts.
 
why is that more difficult? It's an easy fix if you are careful and a magnetic pickup can reach in and get it if you drop it. the lifter bores and cam keep it from falling anywhere suspect. I've seen it done many times in a pinch. In the early aluminum head days with Bob Glidden and other pro stock racers such a repair was commonplace. Its just an air pump. None of these engines that we run are some kind of special thing. you can put 30 grand into an engine for your car and still not have the quality of a hospital generator engine. wake up

If you still have the intake off, lay some aluminum foil under each of the holes coated with wheel bearing grease while "SLOWLY" drilling the holes. Discard the foil carefully keeping the shards in the grease. Use a pencil magnet to pick up any possible escapees. Put down more aluminum foil and then coat the tap with grease, which will keep most, if not all of the shards in the tap. Again use the pencil magnet to make sure the are none left. Put some heavy shop rags under the holes and rinse the holes lightly with a solvent. Put RED Loctite on the Helicoils and slowly screw the in. Let the Loctite cure for at least 3 hours before reinstalling the intake. I know this is very time consuming, but it works. I've done it many times on cast iron and aluminum heads with great success. As I said, use the pencil magnet all around the area many, many times just in case a shard or two escaped.
Pit fixes only get you to the next round. Take it to a reputable machine shop and get it fixed right and you won’t have another pit fix with it.
 
Metric anything is for foreign cars. Foreign car mechanics at dealerships are the highest paid mechanics because working on foreign cars sucks. Metric fasteners are not the only one of their stupid ideas. It’s a criminal shame that their stupid ideas have overcome American automotive manufacturing. Cars used to be rebuildable, now they are just disposable appliances. They used to have style and class, now they look like colored jellybeans. And 95 % of the mechanics out there don’t know how to fix anything, they just know how to replace parts.
I don't like it either. I'd be different if everything that was metric was metric, but it's not. It's better than the late 70s, but it's still not 100%. I can well remember as an example, the alternator bolts on a 305 Chevy in the late 70s. The bottom bolt was still the 3/8 bolt with a 9/16 head, but the top bolts were metric. The rest of the cars were a mix and match of SAE and metric fasteners. It was bullshit.
 
Metric... yuck! All my neighbours are working with metric tools on their cars because Canada is using metric. When they try to help me with my Barracuda they are lost because it's all standard sizing and built before the changeover. I break out my tools while they are still trying to convert standard to metric sizes.
:wtf:

Sorry for going off topic but needed to rant.lol.
 
After years of searching, I FINALLY found a metric 12" Crescent wrench the other day! :D

:rofl:
You joke, but there ARE crescent wrenches marked off in metric.
 
Years ago I had a friend who said metric is the same as sae! he would use metric wrenches on everything. One day he got a 10mm stuck on a 1/2 bolt. he couldn't get it off. He then realized they do not interchange.
 
Sucks to be you for sure.
My metric tools let me make a decent living. I get to deal with BSW once in a while too. You gotta roll with the changes. I agree with the helicoil being the correct repair procedure for a stripped thread.
 
Metric anything is for foreign cars. Foreign car mechanics at dealerships are the highest paid mechanics because working on foreign cars sucks. Metric fasteners are not the only one of their stupid ideas. It’s a criminal shame that their stupid ideas have overcome American automotive manufacturing. Cars used to be rebuildable, now they are just disposable appliances. They used to have style and class, now they look like colored jellybeans. And 95 % of the mechanics out there don’t know how to fix anything, they just know how to replace parts.
The only reason foreign car mechanics make more money per flat rate hour ( that is how we are paid) is because foreign cars are easier to work on than the big three. I have to concede that the big three are just about as easy to work on because of there willingness to copy Asian manufacturing, Chrysler seems to be the best at holding on to American way of thinking and are some of the hardest vehicles to work on "these days"
 
Hey All, Thank you very much for all the answers and guidance. I decided I'm going to just take off the cylinder head to be on the super safe side. I appreciate all the thoughts and input. Super helpful!
 
Metric anything is for foreign cars. Foreign car mechanics at dealerships are the highest paid mechanics because working on foreign cars sucks. Metric fasteners are not the only one of their stupid ideas. It’s a criminal shame that their stupid ideas have overcome American automotive manufacturing. Cars used to be rebuildable, now they are just disposable appliances. They used to have style and class, now they look like colored jellybeans. And 95 % of the mechanics out there don’t know how to fix anything, they just know how to replace parts.

Most any car made today “ domestic” or foreign..all use metric fasteners. Been that way for a while.
And many “ domestic “ cars have more foreign parts in them than many foreign car manufacturers use.
Check out percent of domestic parts used in a variety of popular selling cars today. You will be surprised at what you find.
 
My metric tools let me make a decent living. I get to deal with BSW once in a while too. You gotta roll with the changes. I agree with the helicoil being the correct repair procedure for a stripped thread.
That's all I used for a very long time as a line mechanic. Now, my metric tools are pushed under a work bench in a small roll around collecting dust.
 
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