rounded head bolt.

hello all,

i am trying to strip my spare engine but the first head bolt on the intake side is in poor condition and the txx 55 bit is just turning in it.

i dont want to attack it with a drill as i dont want to damage the head.

can anybody give me any ideas on how i can get this out, as im sure you know the head bolts are verry tight.

hopefull thanks.

weld a nut to the end of it?

Try driving a torx drive into the nut and hope it grips.

ill try smashing a tx 11 in first and hope that works. if not ill try the welder, its a bit if a squeeze though and im a terrible welder so lets hope the torx works ,

cheers guys

just had the same thing happen to me whilst undoing the head bolt.

I ended up having to drill the bolt head off as everything else i tried failed.

To be honest, drilling the head of the bolt was easy in the end.

I used a 13mm drill bit which run nice and slowly took the bolt head of in minutes.

Using one of the other removed bolts i could mark on the drill bit roughly how deep I need to drill in order to remove the head completely. This was only so I could go a bit more carefully towards the end.

Soon as you drill deep enough the bolt head just spins on the drill so you know your done.

As far as i can see,, no damage to the ally head at all as the bolt head should spin before you go deep enough to actually touch the engine head itself.

One word of warning, buy yourself a 'Carbide 13mm Drill bit'.

Anything else will just get hot and not touch the bolt.

The drillbit I used cost £8 from a local company.

Good luck.

Carl

I normally just weld a old socket onto the head of a bolt thats spun.

thanks for all the help guys, i just got it out, with the help of oversized torx bit and a mallet

ill try smashing a tx 11 in first and hope that works. if not ill try the welder, its a bit if a squeeze though and im a terrible welder so lets hope the torx works ,

 

cheers guys

dont do that.. cos once youve not managed any penetration of the bolt youve got more mess to clean up.

the only way is to drill into the centre to allow the head to pop off..

another trick...

drill slightly smaller than is necessary to remove the bolt head so there is some material holding the head on.. then whack your "whatever" size torx bit in and undo it... the head will break off but neatly.. it saves you retrieving the head of the bolt as itll be stuck on your torx tool...

And think where the swarf is going, unless you are doing a full engine rebuild you will need to address swarf going down into the innards of the engine.

And think where the swarf is going, unless you are doing a full engine rebuild you will need to address swarf going down into the innards of the engine.

i'm sure most people take precautions, a fire blanket works wonders:)

im stripping cleaning and rebuilding mine. but there was no swarf with my "smash a bigger bit in " method

Just had this happen to me while stripping engine, haven't got access to welder, so going to try the drill method and hope it works out

You'll scrap a few drill bits and you MUST use top quality bits. The remains of the internal hexagon will chew off the edges of a few drills before you have a round hole. Start with say an 8mm bit, get below the bottom of the bolt's cap, then go up in 1mm sizes. As you get to where the drill cutting edges catch the internal hex drill bits will probably get scrapped unless you have access to a proper drill sharpener. Go slow speed, DO NOT *NOT* snap a drill off, or you are in REALLY BIG trouble. All internal hex and internal spline head bolts need any debris in the internal hex / spline cleaning out, you need a top quality 1/2 inch drive Allen socket, tapped in to make SURE it is really sat in the bottom of the internal hex before you try and undo it with a decent breaker bar with pressure applied steadily, not jerkily. Have fun, how will you stop debris getting into the rest of the engine, or is it a total strip?

You'll scrap a few drill bits and you MUST use top quality bits. The remains of the internal hexagon will chew off the edges of a few drills before you have a round hole. Start with say an 8mm bit, get below the bottom of the bolt's cap, then go up in 1mm sizes. As you get to where the drill cutting edges catch the internal hex drill bits will probably get scrapped unless you have access to a proper drill sharpener. Go slow speed, DO NOT *NOT* snap a drill off, or you are in REALLY BIG trouble. All internal hex and internal spline head bolts need any debris in the internal hex / spline cleaning out, you need a top quality 1/2 inch drive Allen socket, tapped in to make SURE it is really sat in the bottom of the internal hex before you try and undo it with a decent breaker bar with pressure applied steadily, not jerkily. Have fun, how will you stop debris getting into the rest of the engine, or is it a total strip?

Thanks for the advice Chris it's not something I looking forward to doing but needs must.

Am going to get carbide drill set to do the job, and it's a total strip and rebuild as block was knocking.

Am unsure if cost effective to rebuild block or just buy one all ready done as not confident enough to rebuild block myself

If it has been knocking from the big ends it will need a crank and some rods. It would be madness not to rebore and hone it and fit new oversize pistons, a new oil and water pump, all new bearings and seals, new core plugs, blah blah. Starts to get expensive.... Good luck, get Ti coated drills from a reputable manufacturer, NOT Ebay specials. if you break a drill in the bolt it's gonna get silly expensive.

If it has been knocking from the big ends it will need a crank and some rods. It would be madness not to rebore and hone it and fit new oversize pistons, a new oil and water pump, all new bearings and seals, new core plugs, blah blah. Starts to get expensive.... Good luck, get Ti coated drills from a reputable manufacturer, NOT Ebay specials. if you break a drill in the bolt it's gonna get silly expensive.

I suspected little end was gone but after taking engine out and removing clutch found the flywheel bolts were only finger tight, and am doing full rebuild with new bits but was going to go fully forged but now unsure as it's for a NA-T build so thinking would pre-built TT block be good enough

I suspected little end was gone but after taking engine out and removing clutch found the flywheel bolts were only finger tight, and am doing full rebuild with new bits but was going to go fully forged but now unsure as it's for a NA-T build so thinking would pre-built TT block be good enough

There are no little end bearings in 2JZ's mate.

I would honestly just buy a used GE, refresh it with new gaskets and stick it in with a TT head gasket. Mine made plenty of power like that.

There are no little end bearings in 2JZ's mate.

 

I would honestly just buy a used GE, refresh it with new gaskets and stick it in with a TT head gasket. Mine made plenty of power like that.

 

 

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How much power did yours make if don't mind me asking?

And that was meant to say rear end bearings but my iphone must of corrected it the stupid thing