so i busted a bolt on my intake manifold

[haze]

been using 3 pieces of literature to aid in my restoration of my 521 A) the datsun 510 and 521 manual by haynes B)how to rebuild your nissan & datsun ohc engine and C) the datsun pickup service manual. couldnt find any torque specs past this little tid bit in my engine overhaul book : 8 mm bolt 11-18 lbs, 10 mm bolt 25-33 lbs, 8 mm nut 9-12. well everything on my manifolds is 12mm so i didnt know what to do and 30 lbs seemed excessive for aluminum and 10 seemed too low because of the coolant lines running through my intake so i torqued my stuff to 20-25 lbs as a compromise and snapped one of my top bolts on my intake manifold (the ones with the flat washers) straight inside my block.

 

what are the actual torque specs?

 

i hate extractors they all most always seem to break on me and i am fearful that i may have stripped the threads in my engine block to boot. is it possible to just run with one less bolt on my intake or is that just jim bob dumb fuck thinking?

[izzo]

You can torque bolts down to what they are specified, but i wouldn't for intake/exhaust. Get them tight, then another quarter turn. Never failed on me. Never came loose either. Was the bolt old? An extractor should work just fine. if not is there enough of the bolt sticking out you can get two nuts on there and tighten them together, then back it out? Or worst case... vise grips?

 

btw, had an L series missing an intake bolt on it also. ran just fine :D Just gotta watch for leaks...

[haze]

its looking pretty flush brother but i havent taken the manifold off yet .... decided i broke enough stuff for one evening

 

what did you do to prevent leakage on yours? did it leak a lot and/or often?

 

btw yes the bolts were old

[I'm BLUE]

:blink: 10-15isn't it ??? Blue thread lock if worried :)

[banzai510(hainz)]

you just put the intake bolt evenly tight.

Be honest the upper should be studs and the exahust ends are stud and the center exhaust is a stud.

the near center using the washer are bolts.

 

keep from leaking is a new gaskets and evenly tighten

 

olddatsuns.com

[thisismatt]

Hold a nut centered over the bolt and MIG weld the nut to the bolt through the hole in the nut...easy peezy

[H5WAGON]

been using 3 pieces of literature to aid in my restoration of my 521 A) the datsun 510 and 521 manual by haynes B)how to rebuild your nissan & datsun ohc engine and C) the datsun pickup service manual. couldnt find any torque specs past this little tid bit in my engine overhaul book : 8 mm bolt 11-18 lbs, 10 mm bolt 25-33 lbs, 8 mm nut 9-12. well everything on my manifolds is 12mm so i didnt know what to do and 30 lbs seemed excessive for aluminum and 10 seemed too low because of the coolant lines running through my intake so i torqued my stuff to 20-25 lbs as a compromise and snapped one of my top bolts on my intake manifold (the ones with the flat washers) straight inside my block.

 

what are the actual torque specs?

 

i hate extractors they all most always seem to break on me and i am fearful that i may have stripped the threads in my engine block to boot. is it possible to just run with one less bolt on my intake or is that just jim bob dumb fuck thinking?

 

Like h2theizzo said "btw, had an L series missing an intake bolt on it also. ran just fine :D Just gotta watch for leaks... "

You said restoration? So are you planning on taking it apart anyway or do you need to drive this car while restoring?..:huh:

 

Those torque settings may be for the actual thread size.......not the Head of the bolt. You said 12mm.....12mm thread is pretty big!

 

Some non-Nissan bolts from hardware store etc. may be the same thread, but for example the intakes I have bought some have 13mm Heads on them, same thread.

 

Using a 1/4 ratchet one handed its hard to go over 20lbs,,,,..unless your really trying.

These old cars and trucks the bolts can break, I'm getting good at drilling out bolts....:cool: Wait until you take off the fenders!! A nice center punch and quality drill bits will be your friend........If your lucky you can use Vise grips on some.

 

My car was in a field for over 10 years....I went through one can of WD40 just spraying rusty bolts before I even touched them..:cool:

[H5WAGON]

Hold a nut centered over the bolt and MIG weld the nut to the bolt through the hole in the nut...easy peezy

 

Wish I had a MIG welder....:P

[haze]

Like h2theizzo said "btw, had an L series missing an intake bolt on it also. ran just fine :D Just gotta watch for leaks... "

You said restoration? So are you planning on taking it apart anyway or do you need to drive this car while restoring?..:huh:

 

Those torque settings may be for the actual thread size.......not the Head of the bolt. You said 12mm.....12mm thread is pretty big!

 

Some non-Nissan bolts from hardware store etc. may be the same thread, but for example the intakes I have bought some have 13mm Heads on them, same thread.

 

Using a 1/4 ratchet one handed its hard to go over 20lbs,,,,..unless your really trying.

These old cars and trucks the bolts can break, I'm getting good at drilling out bolts....:cool: Wait until you take off the fenders!! A nice center punch and quality drill bits will be your friend........If your lucky you can use Vise grips on some.

 

My car was in a field for over 10 years....I went through one can of WD40 just spraying rusty bolts before I even touched them..:cool:

 

presently the engine block and transmission are sitting on a bench in my front yard overhauled and bolted together and was starting to put all the other goodies on it before i stuck the thing back under the the hood but to answer your question once i have this thing mechanically solid it will be a daily driver as i slowly make it prettier and better. the bolt thing confuses the shit out of me all i know it that when i needed new tranny mount bolts they were M10's at a 1.50 thread size at 50 mm in length (the head size was much larger than the originals) i assumed that when someone refers to a bolt as a 10mm bolt or an 8 mm nut they are referring to the socket that fits upon it. i dont have a welder so i guess i will be trying the taps again and hope they dont break again like they did when i was replacing the bushings on my sway bar. will i need to replace my gasket again once i take my manifold off? or should i just leave this thing alone untill the fucker starts dripping water and tap the bolt out then? or can i tap this bolt out with the manifold still in place?

 

i hope this doesn't sound too random my brain is fried after an 8 hour day in the hot austin sun...over a hundred degrees today

[DanielC]

Bolt size is the major diameter of the threaded part. A typical bolt on a Datsun engine with a 10 MM head is a 6 MM bolt. A 12 or 13 MM head is probably a 8MM bolt, and I have seen 14 and 17 MM heads on 10 MM bolts.

Torque values are for threading into steel. Less torque will be needed in aluminum.

 

A method that sometimes works on removing a broken bolt, if any of it sticks above the surface on aluminum is this.

Hit the top of the bolt end square with a hammer a few times. not hard, not a light tap, but hit it.

Cut a slot in the top of the broken bolt with a 1/32 cutoff disk.

Use a straight screwdriver to unscrew the bolt.

[haze]

Bolt size is the major diameter of the threaded part. A typical bolt on a Datsun engine with a 10 MM head is a 6 MM bolt. A 12 or 13 MM head is probably a 8MM bolt, and I have seen 14 and 17 MM heads on 10 MM bolts.

Torque values are for threading into steel. Less torque will be needed in aluminum.

 

A method that sometimes works on removing a broken bolt, if any of it sticks above the surface on aluminum is this.

Hit the top of the bolt end square with a hammer a few times. not hard, not a light tap, but hit it.

Cut a slot in the top of the broken bolt with a 1/32 cutoff disk.

Use a straight screwdriver to unscrew the bolt.

 

hell yea that is pretty smart...should i be thinkig about changing my gasket agian after i remove this bolt? in a perfact world i would just do it but my local car shop only sell this gasket in a complete engine gasket kit for like 30 or 40 bucks and it takes around a week to order

[king bee66]

if you just put a fresh gasket on before you snapped the bolt i would think its reusable although, ive never torqued a mani gasket. but thats a great deal for a complete engine gasket set. a head gasket alone for my a14 was 30$. fyi, i lost one of my mani bolts while i was hooking it up and ive been rolling without it there for 10k miles now, its fine.

[haze]

if you just put a fresh gasket on before you snapped the bolt i would think its reusable although, ive never torqued a mani gasket. but thats a great deal for a complete engine gasket set. a head gasket alone for my a14 was 30$. fyi, i lost one of my mani bolts while i was hooking it up and ive been rolling without it there for 10k miles now, its fine.

 

rad! i am definitely inspired you are the second person to tell me that you have been running with one less manifold bolt without any issues. think i am going to leave this bitch ass broken bolt alone put some thread locker on my other bolts and torque them down in accordance to what h2theizzo said and see what happens. if i get some leakage ill just order another gasket set and radiator fluid then drive my little booger to a buddies house with a welder and try out that MIG trick

[Spades]

this is my opinion, take it or leave it. How much does a intake manifold gasket cost? how much is your time worth? what if you do not replace the gasket, and it leaks later? do you want to risk breaking a stud again?

 

if you have no cash, and lots of time, it is a very worthwhile gamble, but if you have a job, and not as much time, the few dollar gasket is worth it (it is to me anyway).

 

We have had techs where I work try the "I will re use the gasket, its brand new" after they were reassembling intake manifolds and left something off. The end result was the car always came back, and eventually, those goobers were fired, and we would loose a customer over a stupid $5-$20 gasket. So, personally, I usually replace the gasket.

[haze]

this is my opinion, take it or leave it. How much does a intake manifold gasket cost? how much is your time worth? what if you do not replace the gasket, and it leaks later? do you want to risk breaking a stud again?

 

if you have no cash, and lots of time, it is a very worthwhile gamble, but if you have a job, and not as much time, the few dollar gasket is worth it (it is to me anyway).

 

We have had techs where I work try the "I will re use the gasket, its brand new" after they were reassembling intake manifolds and left something off. The end result was the car always came back, and eventually, those goobers were fired, and we would loose a customer over a stupid $5-$20 gasket. So, personally, I usually replace the gasket.

 

my question is this: if i have not taken either of my manifolds off yet is the gasket still good?

 

the bolt that broke was the last one i was torquing down and i havent touched the block since past backing the other bolts down to 10-15lbs the following morning

 

i know this is a half assed short cut but i ask because both time and money are very tight these days( i still need to buy a radiator, distributor, alternator, rear breaks bearings and shocks and at least some new seals for the differential because its leaking oil though i havent opened it yet) and a running truck equals a raise at work. but if the gasket is possibly shot from backing off the existing bolts from 20lbs to about 12 of course i will spend the time and money doing this thing right including replacing the bolts driving out the broken bolt and getting a new gasket. i dont want to back track but i dont want to screw up anything either