Dealer stripped the oil drain plug...

[slow84lx]

I started out this reply as with some serious haterade but in the recent spirit of being nice I'll explain this to you without being a dick. I also should have added the disclaimer "when used properly".

When installing a helicoil, you have to slightly overdrill your threads to accomodate the larger diameter of the insert. This in turn increases the shear area thus increasing the ultimate fastening strength. Furthermore, the flexibility of a helicoil (spring like) allows more proper load distribution throughout the tapped hole. The only way I can imagine a helicoil will ever be weaker is if it's used improperly and put into some exotic VERY strong and VERY hard material that an insert cannot accomodate. But I don't see that happening as damage should occurr to fasteners first.

Any good engineer/designer should know the considerations to make when using threaded inserts of any sort and should ensure there is enough thread engagement and appropriate material selection. Several aerospace and defense applications will use helicoils in ALL holes because of the strength and reduced thread wear they provide. And I am talking in the as-new condition, not as a repair.

The TimeSert you reference does have applications where it may be better suited than a helicoil, but it is not better. All threaded inserts have their time and place. There's a reason Helicoil is among the most widely used and accepted.

Going along with the new spirit of niceness on DFWMustangs I will only state that I stand behind my previous statements and give a short explanation.

I've worked with large industrial printing machinery since 1987. I've seen dozens of helicoil inserts installed and quite a few of them fail. I've installed them myself on various car parts over the years with success but everytime I see a helicoil I know that care has to be used in that hole due to the insert. They will pull before the needed torque is reached, come loose when in usage, or back out next time the bolt is removed from that hole. Not always, but I have experienced problems often enough that a Helicoil is the last resort for me. This opinion was formed from personal experience using this product, (including the correct drill bit).

I've used other inserts a few times and have been impressed with them over the HeliCoil insert. In particular, I used TimeSerts in my Caddy Northstar block in all 20 headbolt holes. They worked like a champ and are as strong as the original steel bolt in an aluminum block. Could this insert fail? Sure. It could also back out when the bolt is removed.....but, I haven't experienced this failure with Timeserts although I have many, many times with HeliCoils.

The proper tool must be used for any job and some tools in our boxes are inserts of one style or another for thread repair. I made a personal decision many years ago to never use another Helicoil insert if there were any other option. In the case of an oil pan I think the next size bigger bolt or a new pan are better options than any insert.

[1995RedGT]

if only the dealership in question has done the oil changes then yes id be rather upset. But if the oil has been changed at other places/at home then it slightly harder to place the blame on someone.

My brother owns an oil change shop and i worked there for a bit and sometimes cars come in with crossthreaded drain plugs. So as soon as we saw a problem we told the customer and asked who the last person was to do the oil change.

If only one place has done the oil changes and its a dealership, then yea id be pissed. Hell if it was my car id be mad no matter where it was.

[HarrisonTX]

I have no idea how people fuck up drain plugs so much.

I trust helicoils. I've only seen one fail, and it was in a drain plug coincidentally. In that case I question the installer. installed correctly I think theyre fine.

I haven't used them but a few times. My first experience was in an SBC head bolt hole. Held so far and the head has been off twice, and torqued to 70 ft/lbs.

I still don't understand how people fuck up drain plugs so much.

[68RR]

Helicoils and variations have been used in aviation engines , landing gear and flight control components for probably close to a century now. If properly installed there shouldn't be any problems. However, if they admitted to screwing up the pan, they should replace it.

[Ruffdaddy]

My point exactly, in MOST cases...if helicoils don't work better than softer parent threads...you're using them wrong. There are very few cases a Helicoil may not be stronger and over drilling isn't always the answer if possible at all. To say they are weaker couldn't be more wrong.

[dcs13]

WELL, today I notice I have oil drips on my garage floor. Sure enough, there's oil leaking from the plug.. Guess they didn't get something right....We'll see how "easy" this goes with Huffines
I think I am more pissed about the oil on the floor. The concrete has always been perfect and I want to paint the floor in there one of these days...

[big_tiger]

A helicoil is dumb, Time-serts work; shit even the self tapping oversized. I know Honda likes using short drain plugs, even though the threads in the pan are twice as long. Bet the tech did use a torque wrench, they need to have preset torque wrenches, to idiot proof that issue. Good Luck