Guys, I made a mistake trying to extract a hole from my 1981 Fiat Spider. An EZ out broke off in a head bolt hole and I had to drill around it to remove. Now I'm left with no threads and a larger hole.Other than replacing the block what other options do I have? I was thinking about the best metal epoxy I can find (that has similar expansion rates to iron to match the block) and retap'ing using a time-sert / big-sert or similar.http://www.timesert.com/html/bigsert.htmlI really don't want to rebuild this engine. A pain in the *ss mistake for sure. Next time I'll use left handed drill bits or the welding a nut to the broken bolt trick!
You took the hole out alright. "I made a mistake trying to extract a hole..."Sometimes a guy has to know when to stop, drop back, and punt. I think you should have stopped when the EZ-out broke. A good machine shop could have gotten the bolt/broken extractor out. It may have required disassembling the lower end too but at least you wouldn't need to replace the block.It may be fixable but it needs to go to a machine shop. Might be able to round out the hole that is there, install a bushing in the hole that has the correct size threads for the head bolt and be in the correct location.I don't think JB Weld will do the trick in this case.GOOD LUCK
thats really just barely fixable..its going to be cheeper in the long run.. to buy a different block and start from there..even finding a engine core supplier to purchase the engine from...or search the classified for a proper donor for the entire engine...seems the 2.0 dohc was used from 80 thru 83 or was it 85.. putting the 2.0 head on a 1.8 block but there are differences that are kinda hard to overcome..if you plan on attempting to fix this your self..please invest at least in a set of transfer punches.. so you can use the cylinder head as a guide to make a drilling jig.. make several sets of marks .. so you can move it along to increase the size of the hole you are drilling... you might end up using a hole saw if you can find the proper size to cut using the jig to align it.. straight thru the rough area. please think before going all the way thru completely..this should give you straight sides to run the proper size drill and then tap it to the size of the probable bolt size you are going to use.. if you get this perfectly centered and square.. you might be able to drill and tap the center of the bolt on a lathe to allow you to use a bolt and jam nut to thread the insert in and out while trying the fit..you will have to trim it to perfect length.. to be square and level with the deck surface..this usually requires surfacing the block. but wow.. with some bolt there. it is going to take a block grinder instead of a rotary broach.. for fear of breaking the cutting tool off..
please... seal your deck surface while you are working and drilling with a small roll of aluminum foil tape... from the plumbing and heating department of the hardware store.. stuff used for HVAC ducting.. not cloth.. actual aluminum foil with sticky on the back side.. so you keep as much of the debris out as possible..you will also want to invest in a tube of hylomar from permatex.. and put a thin coating on both sides of the head gasket.. this will help prevent head gasket leakage in the future..change the other head bolts also..
Dude you need to tear it all the way down and take that to a professional.(I do this kind of stuff for a living) DO NOT TRY TO FIX THIS YOURSELF!!!!You will make it worse.