ARP head bolt giving me F@*%ken problems

[DALAZ_68]

so finishing up the engine rebuild i ran into probably the last thing i wanted to see happen
one of the ARP head bolts was not screwing all the way in...the front right bolt was just not screwing all the way in...which is ridiculous


as you can see on the closest right bolt...its higher by about almost a 1/4


the final bolt isnt lining up with the rest...

i shot some brake cleaner and pb blaster in there to clean it out, still no go...even shoved a tap kit in there and still nothing...the bolt wont go further, the threads on the original wernt rusted or crossed threaded...so anyone got any advice here...should i just try and keep screwing it down, or what...this is pissing me off...

we test fitted the head and theres just enough thread to allow the head to be properly torqued down... but i dunno thoughts

[sjbsuperman1425]

mine was like that too, its supposed to be like that. assemble like it is and have fun

[r34 gtr]

Yeah buddy, that stud never sits all the way in. Not on any CA18. You will need to measure the clearance, but I had to put two washers on there to get the nut to properly tighten down on that stud.

[DALAZ_68]

are you serious...well then...good things i did that...lol


lol

[themadscientist]

Did you use a bottoming tap? They are the same size and have cutters all the way to the end. If you use a standard tap, they are tapered at the end because they are designed to start with a hole not existing threads and need to ease their way in at first. As such, it would not chase the last threads at the bottom of the hole like a bottoming tap would.

[float_6969]

That hole is above the water pump area, and as such, it can't be as deep as all the other holes. This isn't an issue in the stock bolts as they are short enough that you don't notice, but when you go to ARP head studs and the bolt bottoms out, it's quite noticable. The most common solution is to add some extra washers under that particular nut and call it good. It seems to vary greatly from engine to engine, as on mine, it's barely noticeable.

[s13drifter88]

add 1 of the stock head stud washers on top of the ARP washer for that stud only. continue assembly, install and enjoy
float we need a sticky for this exact thing. i know this isnt the first time many of us has seen this asked

[DALAZ_68]

Sweet great to know...ill deff add a washer on there and push fowards...

[float_6969]

I thought about it, but realized nobody reads them. LOL!

[float_6969]

OK, I added a note about it in with the Part Number list.

[DALAZ_68]

i hope its my thread...lol

i still havent gotten my title for my how too thread...lol

i think i still have one of the original washers...s*** going in...

[blownhemi]

Euro head (w/ the Euro ARP part#) didnt have this problem. Is it so much different in that area?

[DALAZ_68]

Euro head (w/ the Euro ARP part#) didnt have this problem. Is it so much different in that area?

pfft who knows...a comparrison or measurement of both JDM and EDM bolts would be nice to see...

[Spawn_CA18]

i had the same "problem" as you .
just use extra washer thats all .

[themadscientist]

I would grind the stud shorter rather than stacking washers, but that's me.

[Spawn_CA18]

I would grind the stud shorter rather than stacking washers, but that's me.

from block side ? this make stud less capable to hold compression i think.

also studs are really solid parts. i think will be very hard to make it shorter.

all peoples are using long bolts like this . even 500bhp CA18det that we made is same like this. and no problem at all .

[themadscientist]

How? The stud is not screwed in all the way so any threads unused are no help. Might as well make it shorter and not stack two washers which is arguably going to increase the possibility of the stud and nut shifting around. Take two washers stacked and hold them between your thumb and forefinger as tight as you can and impart a bit of load like you are snapping your fingers. They slide right off each other don't they? A shortened stud alleviates the need for this setup.

I think my way is better, but the other way is not bad either, just not the way I would go.