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Engine Specific Info and Questions => IDI Engine => Topic started by: 92EcoDiesel Jetta on August 04, 2011, 06:19:06 am

Title: TTY head bolt and block hole prep
Post by: 92EcoDiesel Jetta on August 04, 2011, 06:19:06 am
I am getting ready to install the head w a new head gasket. I made a thread chaser out of an old bolt ( dremel to cut 4 flutes for chip clearance) and ran it through the block holes w WD-40 as a cleaner /lube then blew it out w compressed air. Do the threads have to be totally free of oil to achieve the correct final torque value? I.e. do I have to degrease the bolts and block threads with brake clean before head install?
Title: Re: TTY head bolt and block hole prep
Post by: theman53 on August 04, 2011, 06:52:17 am
I do. WD-40 sucks as a penatrant/rust breaker, but is very slippery. That could change your intitial torque, which will change the final 1/4 turn sequence as well. BUT this may only make a 1/32 of a turn difference I don't know. I just make sure nothing is in the hole like you have so you don't crack the block with hydraulic pressure.
Title: Re: TTY head bolt and block hole prep
Post by: 92EcoDiesel Jetta on August 04, 2011, 07:27:55 am
The only concern I have with totally dry threads is rust and problems with stripped bolt heads/broken bolts in the future.

Does it matter if I install the head by itself then install the in/ex manifoled?  Or head+ in/ex manifold as an assembly? It would certainly be easier as an assembly. To prevent marring up the head gasket, I would make 4 shortened guides out of the old head bolts with a slot on the head so I can get them out with a screwdriver and a magnet.
Title: Re: TTY head bolt and block hole prep
Post by: theman53 on August 04, 2011, 07:33:07 am
All the ones I have taken off even after 10 miles but the heat cycle*had one that shot oil out the front at first start* Had oil down in the threads after running. I dont think it would rust. They are blind holes with no coolant around them.
I usually install with everything hanging off of them. But the last one that I studed the studs put the turbo into the rain tray and I couldn't get it on there that way.
Title: Re: TTY head bolt and block hole prep
Post by: 92EcoDiesel Jetta on August 04, 2011, 07:46:28 am
I'm not understanding your last sentence. How long were your guide studs? I was going to make them protrude only 1/2" above the deck to avoid any clearance issues.
Title: Re: TTY head bolt and block hole prep
Post by: R.O.R-2.0 on August 04, 2011, 07:56:38 am
I'm not understanding your last sentence. How long were your guide studs? I was going to make them protrude only 1/2" above the deck to avoid any clearance issues.

how you gonna get them back out with the head on?

he was talking about head studs i believe..
Title: Re: TTY head bolt and block hole prep
Post by: theman53 on August 04, 2011, 07:59:48 am
ARP studs.

I have made the studs you are talking and they stuck out about 2" and were fine.
Title: Re: TTY head bolt and block hole prep
Post by: 92EcoDiesel Jetta on August 04, 2011, 08:25:06 am
Maybe you missed what I wrote ealier:

"I would make 4 shortened guides out of the old head bolts with a slot on the head so I can get them out with a screwdriver and a magnet"

To clarify that some more, the guide studs (made from old head bolts) would have the triple square head chopped off and shortened (if that wasn't done it can't work as a guide, the head won't go over the triple square head), then a slot cut into the head of the stud so I can undo it with a screw driver. To insure it won't hang up in the head during removal, I can grind it a hair smaller in diameter and also taper the portion not threaded into the block. Do you still see a problem?

I'm not understanding your last sentence. How long were your guide studs? I was going to make them protrude only 1/2" above the deck to avoid any clearance issues.

how you gonna get them back out with the head on?

he was talking about head studs i believe..
Title: Re: TTY head bolt and block hole prep
Post by: 92EcoDiesel Jetta on August 04, 2011, 08:26:45 am
I was talking about TTY head bolts. So you don't see any problems with what I'm doing?

ARP studs.

I have made the studs you are talking and they stuck out about 2" and were fine.
Title: Re: TTY head bolt and block hole prep
Post by: 92EcoDiesel Jetta on August 04, 2011, 08:33:46 am
So you are talking about studs, not bolts but it shouldn't matter. Are you saying oil will slowly get into the blind holes when the engine is running??? That can only happen if the head gasket is not doing its job. I'd think the oil you saw in the blind hole was from oil spilling into it after the head was removed, not while the head gasket was on.

All the ones I have taken off even after 10 miles but the heat cycle*had one that shot oil out the front at first start* Had oil down in the threads after running. I dont think it would rust. They are blind holes with no coolant around them.

Title: Re: TTY head bolt and block hole prep
Post by: R.O.R-2.0 on August 04, 2011, 08:36:55 am
i forgot the heads are aluminum, and the steel pieces can easily be picked back out with a magnet..
Title: Re: TTY head bolt and block hole prep
Post by: rodpaslow on August 04, 2011, 01:57:30 pm
not saying you should have oil in the bottom of a hole, but ARP uses a special grease/oil lubricant.  I'm asking - don't you usually want some form of lubrication before torquing anything?
Title: Re: TTY head bolt and block hole prep
Post by: theman53 on August 04, 2011, 07:18:35 pm
ARP moly lube is only used on the business end=nut end. DRY or RED threadlocker is to be used on the block end and the threadlocker is to be torqued before hardening.

you said:I'd think the oil you saw in the blind hole was from oil spilling into it after the head was removed, not while the head gasket was on.

The washers and head and bolts are not sealing pieces. They are clamping and since there are little places for oil to get in and run down the bolt eventually it will. The headgasket doesn't make a positive seal around the bolt. The ones I have done that have 160,000 plus miles on them have old nasty not flowing cooked looking oil. Not the nice new black runny oil from the HG. I could be off but I swear it comes down the bolt while running.
Title: Re: TTY head bolt and block hole prep
Post by: 92EcoDiesel Jetta on August 04, 2011, 08:01:23 pm
The washer on the those TTY head bolts is pretty flat and smooth. With 100+ ft lb torque on it one would think oil cannot infiltrate through the washer.  The only exception is the oil feed head bolt. I think it's the one between #3 and 4 on the front of the head.

On the ARP studs, if the block end of the stud has red locktite how do you remove the head when needed?
Title: Re: TTY head bolt and block hole prep
Post by: theman53 on August 04, 2011, 08:29:19 pm
I didn't threadlock mine, but there is a hex drive in the center you could try and turn them out. Also, mine fits without the turbo on and the studs in place.

Yes they are fairly flat and smooth, but they are not through hardend and not 100% sealing surface. They leak over time. Heck some pipe threads that were meant to seal sometimes still leak. These are bound to, therefore won't rust.
Title: Re: TTY head bolt and block hole prep
Post by: 745 turbogreasel on August 04, 2011, 08:41:08 pm
Most of the motors I pull down seem to have about half rusty, half oily :D