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KaptKaos
Haynes says 23 lb and give a tightening diagram.

That 23 lbs included the old head gaskets, which I am not using.

Does the torque setting need to be tighter without head gaskets?

If so, what?

TIA
McMark
Nope.

Tighten them to 12 first. Use the correct sequence.
KaptKaos
Mark,

So tighten them to 12, and then go through again to 23?

I already tightened them to 23. Should I undo and re-do?

Thanks.
detoxcowboy
I think mcMark means that it is better to creep up on a torque setting than torque right to the mark, reason being is to even out the torque across the head.. and more likely assure the torque setting from your first nut is still what you set it at when you set the last nuts torque.. bect..,
KaptKaos
I get that. Make sense.

Should I loosen and re-torque?
craig downs
Yes
detoxcowboy
Yes, peace of mind, easier now.. be certain w/ less variables..
KaptKaos
Got it. Thanks guys.
Tom_T
QUOTE(KaptKaos @ May 16 2010, 03:25 PM) *

Haynes says 23 lb and give a tightening diagram.

That 23 lbs included the old head gaskets, which I am not using.

Does the torque setting need to be tighter without head gaskets?

If so, what?

TIA


Wut!!?? - no head gaskets!? confused24.gif

How to you plan to stop blow-by from torching your heads & ruining the surface? confused24.gif
.... or are you using a liquid/paste redi-gasket type product?

BTW - you can warp a head by over torquing or going in one step to the spec, instead of edging up to it, &/or not doing the recommended pattern to opposite corners - esp. on aluminum & other alloy heads! dry.gif
KaptKaos
It's my understanding that VW even changed their spec and removed the head gaskets from their rebuilds.

The cylinders were lapped into the heads.

I've heard that Jake uses spray on copper gasket material in the combustion chamber. Supposedly, this creates a good seal for the cylinders to the heads and the excess just burns off. I haven't done that but now that I need to re-torque the heads I might.

Any other hints or tips?
detoxcowboy
QUOTE(KaptKaos @ May 17 2010, 07:51 AM) *

It's my understanding that VW even changed their spec and removed the head gaskets from their rebuilds.

The cylinders were lapped into the heads.

I've heard that Jake uses spray on copper gasket material in the combustion chamber. Supposedly, this creates a good seal for the cylinders to the heads and the excess just burns off. I haven't done that but now that I need to re-torque the heads I might.

Any other hints or tips?


"It's my understanding that VW even changed their spec and removed the head gaskets from their rebuilds.

I have read the same..

I can't confirm nor denie what Jake is doing, but also thought I read he does not use head gaskets either.. after issue with them ect..
Tom_T
Krusty - the torquing tip or rule of thumb that my Dad & Uncle taught me for tightening any of these things was: "opposite corners in thirds" - so you do a finger tight on everything, then step up in 1/3, 2/3, full or 3/3 of spec torque (some use 1/4's) going in turn to the bolts/nuts in the opposite corners - ro farthest opposite from each other, back & forth in an X pattern. Obviously with 3 or 5 etc. you need to improvise, but the patter is the same. Ergo, the factory manual instructions to which you refer, & never over-torque on a soft material such as aluminum or alloy parts (e.g.: heads).

IIRC - VW/Porsche changed the gasket material not eliminated them - although some "builders" apparently do what you mentioned Jake does or similar, but then I have half-zymers! blink.gif

Lapped in or not, the purpose of a solid or applied gasket is to fill in the irregularities on the two surfaces & differential thermal cycling - which lapping doesn't address. While they may start out seating perfectly, over time the high heat at which these things run changes that, & the gasket material fill any voids as it heat cycles. The steel/iron cans & aluminum heads have different rates of temperature expansion/contraction, so that also varies as the engine temp cycles.

I can ask my long time mechanic Hans, who was factory trained on these before he came over here & opened his shop in HB. He knows a lot of the old history & what works & not with the stock set-ups.

However, it sounds like yours is the non-stock flavor.

One thing I do know to be careful about, is to use a gasket liquid/paste/spray which won't "eat" the aluminum in the heads, as some chemical formulations apparently wreak havoc due to electrolytic reactions - even if not acidic themselves.

You probably know that VW "discovered" that corrosion problem too late with their Vanagon waterboxers, where the combination of materials in their original coolant, case, cylinders/jackets, heads & gaskets caused the aluminum heads to eat away & lose coolant within about 40k miles (some as fast as 20k). They only partially rectified this problem with the 2.1 & the rebuild kits & coolant formulation in the mid-80's, as I know only too well, having now had 3 sets of heads on our 88 Westy over 200+ k miles (counting the factory originals)! dry.gif
Cap'n Krusty
I see my name, but don't know why it's in a post.

My opinion after 37 years of building 914 engines:

A: Yes VW dropped the head gaskets, BUT ONLY ON THE 2.0 BUS ENGINES, and only when doing a rebuild. They also changed the head design. If you leave out the gaskets but use the original 2.0 BUS HEADS, you must add a spacer to the base of each cylinder to bring the compression back to specs. Porsche NEVER dropped the head gaskets, and never specified or suggested they be eliminated.

Jake has had great success with deleting the head gaskets. He has his own reasons, and his own experience. His experience is much shorter than mine, but he has done far more engines than I, and has done an amazing amount of R&D on the T4.
HOWEVER, I doubt he deletes the gaskets on all his engines because "VW did it".
That is a LAME excuse, and not even any kind of defensible reason, and it's taken out of context.

B: Competent machinists use a vertical mill to surface 914 heads. Mills are huge, heavy, and designed to deliver precise, repeatable cuts to the work at hand. You're taking a pair of matched precision surfaces, separated by an inch or more of material, and lapping them by hand? WHAT ARE YOU THINKING! I, for one, am not blessed with either the eyesight or the hand/eye coordination to lap a pair of cylinders to a cylinder head with any sort of planar accuracy, especially to .0001". How do you know you're holding the cylinders at precisely 90 degrees to the surface of the head? How about the depth of cut? I doubt you, or anyone else on this planet, can match the accuracy of that mill in the hands of a competent machinist. If your machinist isn't all that competent, we've just moved to another subject altogether ................

The Cap'n
Tom_T
QUOTE(Cap'n Krusty @ May 17 2010, 01:18 PM) *

I see my name, but don't know why it's in a post.


My mistake Krusty - due to half-zymers, when my brain farted & went from KapnKaos to you when I wrote that! blink.gif
... apologies!

But you are reinforcing the "use the head gaskets" line that I've heard too, & don't think I'd drop the gaskets off the 914 engines for mine - and you've been around about as long as my guy Hans down in Huntington Beach, so you certainly know!

The Vans I was referring to above were the waterboxers - not 2.0 Type IV Buses - just to be clear.
KaptKaos
When I took her apart, there weren't any head gaskets. She ran good and I wouldn't have taken her apart had I not messed up an exhaust stud.
KaptKaos
Here's a Jake post for reference:

http://www.914world.com/bbs2/index.php?s=&...st&p=535826

Tom_T
QUOTE(KaptKaos @ May 17 2010, 04:35 PM) *

When I took her apart, there weren't any head gaskets. She ran good and I wouldn't have taken her apart had I not messed up an exhaust stud.


Joe, based on what Krusty said, could you have a bus 2.0 in there? confused24.gif

IMHO I'd stick with head gaskets unless spec'd without, unless it's a FAT or Raby with the spray-on alt.

I recall your stud wanking post - too bad! sad.gif
jaxdream
That's nice to know , how about the 1.7 and the 1.8 , do they also need the head gasket installed also ?? WTF.gif

Jack / Jaxdream the guy that brought you the pickle fork
detoxcowboy
QUOTE(Tom_T @ May 17 2010, 04:53 PM) *

QUOTE(KaptKaos @ May 17 2010, 04:35 PM) *

When I took her apart, there weren't any head gaskets. She ran good and I wouldn't have taken her apart had I not messed up an exhaust stud.


Joe, based on what Krusty said, could you have a bus 2.0 in there? confused24.gif

IMHO I'd stick with head gaskets unless spec'd without, unless it's a FAT or Raby with the spray-on alt.

I recall your stud wanking post - too bad! sad.gif


I use head gaskets, I made no statement as to other that fact of what I read re vw, but that would not be reason enough for me to follow suit, I am not a sheep sheeplove.gif and not a machinist.. I never hand lapped anything.. and yes I have bus pistons in there from the p/o/'s budget rebuild, also have New Euro Pistons to go in eventually, I bet your assuming what you have in your 914. Please leave me out of this.. thank you..
Tom_T
QUOTE(detoxcowboy @ May 17 2010, 05:44 PM) *

I bet your assuming what you have in your 914.


Nope, they're proper 914 2.0 USA GA engine spec'ed pistons, cylinders & heads, because it was an overhaul of the original engine, & I still have the 10/83 invoice from Hans! smile.gif
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