what to do about striped head bolt holes in the block

[DISLEXICDIME]

Ok

 

today i decided to putt my a87 head on i just had rebuilt. When i went to chase the threads i found that the top thread on one of the holes was broke off and that made it want to cross thread. Has any one had this happen? If so How did you fix it? did you just run a tap through it? Are the threads for the head bolts 10mm x 1.50 ? :confused::mad:

 

 

thanks in advance

mike

[dat521gatherer]

yep thats what a tap is for, fixing or making threads. what hole are you talking about? tower cam? ball stud? manifold?i stripped out a cam tower once and just put some epoxy or jb weld i dont remember. sometimes just taking those tower cam bolts will take the threads up with them for some reason. i've tapped out every hole on my truck to its original threads even when i have broken studs. i drill then tap to the original size.

 

i refuse to use heli coils. i'll use the next size up bolt if i can.

 

just make sure the tap goes in straight and it should find the right path.

[DISLEXICDIME]

nope its not the cam bolts :) i am talking about the holes that the head bolts go in. The bolts go through the head and thread in to the block. The threads on one of the holes in the block is messed up. The top thread is busted out of the hole. I think i snagged it when i pulled the bolt out of the block.:blink:

[dat521gatherer]

head bolt hole on the block huh. seeing that the bolt goes in like an inch i'd just tap it and test fit a bolt in it. should be easy. i dont know what size tap that is sorry.

[SHADY280]

get the proper tap, run it thru, it should be o.k. a piece of the top thread wont matter as long as the rest are o.k. if it screws up, id use a heli-coil. when used correctly, they work perfect and retain stock bolt size. that and when used in the block type applications, you need the good ones. also it keeps the torque spec equal for everything, therefore not warping your head, or messing the gasket.

[DISLEXICDIME]

operation tap that shit was a success thanks to harbor freight's $10.00 tap set and some atf (used it for cutting fluid! thanks nismo pu for the tip ) :)

[slodat]

Nice work Mikey! How does it run with the new head??

[DISLEXICDIME]

it is not on yet. i am taking a baja fresh brake :P

[808DA6]

operation tap that shit was a success thanks to harbor freight's $10.00 tap set and some atf (used it for cutting fluid! thanks nismo pu for the tip ) :)

 

....:blink: are we still talking Datsun? Use the atf and tap that shit yo! :lol:

 

Sorry. Had to do it.

 

-Brian

[dat521gatherer]

careful with those harbor freight taps. the absolute worst thing you can do is break off a tap in a hole. i buy mine individually from tool town or tacoma screw.

[DISLEXICDIME]

i took my time and used a lott of atf and stopped a couple times to let the tap cool off

[slodat]

How did it turn out?

[DISLEXICDIME]

its not finished yet. I set up the valve lash and putt in the exhaust manifold stud's.

then i decided that i wanted to watch return of the living dead and eat some pizza. so that is as far as i got . its nice having another car to drive.:)

I figure i will finish it tomorrow

[banzai510(hainz)]

make sure the oil pump has oil in it.!!!!!!!!

I always pour oil over everything and down the chain. right before start up.

[DISLEXICDIME]

thanks for looking out hainz. i was already planing on showering the cam rockers and down the chain with oil