Page 2 of 2

Re: Super Rat 93 Cylinder Head Repairable??

Posted: Thu Oct 05, 2017 5:55 pm
by efkruger
Timesert is what Jack used to fix his head. Its a one piece thread repair piece just like what I am talking about previously. I did not know about this until he told me how he repaired it. I need to investigate it and see what size tap it uses to install with. Helicoil uses there own special taps making them somewhat expensive to use. If this timesert piece uses a standard size inch series taps that would be great. You would not have to buy that special tap like Helicoil uses, you could just use whatever standard size tap it uses. Most mechanics have taps in there tool sets. The timesert piece can be tightened down snug as a bug because it has a small flange on it. That's an improvement over Helicoil. I am going to investigate this timesert further. Thanks guys

Re: Super Rat 93 Cylinder Head Repairable??

Posted: Mon Oct 09, 2017 6:41 am
by rlkarren
Timeserts don't use standard taps. But one great advantage to using a timesert is that they are easily removable if ever needed. I used timeserts on a SR engine that had two of it's cylinder studs stripped. I didn't know there were timeserts big enough for a sparkplug hole. This is good news, I didn't think to even look. I have a Wombat head that has a stripped spark plug hole. Spent the longest time looking for the air leak, until the cylinder compression popped the plug right out. That would be a fix I can do.

Roger

Re: Super Rat 93 Cylinder Head Repairable??

Posted: Mon Oct 09, 2017 7:25 am
by Bill2001
Timeserts don't use a "regular" tap, but they don't use a custom tap. It's a certain size/fit grade that is available. I'll look it up later.
Timeserts have a special insert that is used to repair a stripped helicoil. It's got a thicker wall and is called the "Bigsert". Used to be that the only way to fix a stripped helicoil was to double-helicoil it.
Still, helicoil is a good repair for many uses. It's approved for aircraft engines and airframes.

Re: Super Rat 93 Cylinder Head Repairable??

Posted: Mon Oct 09, 2017 3:45 pm
by racerclam
Super Rat head has higher compression as well as more cooling fin area. Dome shape differs also thus different piston used also

Rich