Strike two :(

[vigilant104]

I agree, which is why I opted not to exchange my heads for new ones. The TIME-SERTS look like they are extremely robust and I'm happy with my decision. That said, if one had to spring for the tool(s), it does represent a significant expense (~ $150 USD for the 12 x 1.25).The inserts themselves are negligible, < $2 each.

A tool like that might make a good start for a "Sonex Builders and Pilots Foundation Virtual Loan Locker". Pay the whole price up front, get $130 back when the tool is returned.

[vwglenn]

And I'm not sure I agree with your opinion of heli-coils being bandages, vwglenn. Have you had bad experiences with them? I'd sooner believe that they would be a lot more robust than plug holes badly threaded into aluminum . And who's to say the replacement heads will be necessarily better?

I haven't had any issues with them but I simply don't use them on the spark plugs based on other peoples experiences. Most of the guys I've known who used them said they didn't last very long (not a very large sample of guys 2-3 maybe). I heard one let go at a cruise-in. The engine kept running but the noise it made coming out and afterwards was terrifying. Plug and coil came out together. Possibly installation error? Ya never know with VW guys. Enough to convince me I don't want that to happen? You bet.

I don't think its a function of the helicoil itself but a matter of meat. Most VW heads crack between the valves over time. This is pretty much because of the small amount of metal between them. If you look at the amount of meat between the valves and the amount of meat between the plug hole and the valve (on a stock head) you'll see a very similar correlation between the distances. My assumption is the more meat you take out (ream it for the coil) the more prone the head is to cracking and releasing that coil or the plug. A helicoil is just basically a spring. If the metal around a helicoil weakens from a crack, so does the ability of that coil to hold the plug in place.

I will never profess to be an expert on the VW engine. I'm far from it. I just go with what I know/learned after driving one around daily for almost 20 years. My opinions are just personal opinions but they're usually based on practical real world experience. I believe the readers here can benefit from that but, like all internet message boards, your mileage may vary.

TIME-SERTS look like a better option and are more along the lines of a "case saver" which appear much more robust.

[Sonex1517]

I agree, which is why I opted not to exchange my heads for new ones. The TIME-SERTS look like they are extremely robust and I'm happy with my decision. That said, if one had to spring for the tool(s), it does represent a significant expense (~ $150 USD for the 12 x 1.25).The inserts themselves are negligible, < $2 each.

A tool like that might make a good start for a "Sonex Builders and Pilots Foundation Virtual Loan Locker". Pay the whole price up front, get $130 back when the tool is returned.

We would be happy to add this to the tool loan list. I have to admit though, few have taken advantage of the program.


Robbie Culver
Sonex 1517
Chicagoland
Tails and Wings complete - finishing fuselage.
N1517S reserved

[DCASonex]

Robbie,

Please add my tools for grinding inside of fuel tanks for oops fittings to the foundation's tool rental.

David A.