26 lbs boost, head gasket...poof

[rodpaslow]

Finally got everything running and I now have the problem to try and remove all the oil from the cooling system.  I see many different ways of doing it on this forum, I think I will use a flush product and a bit of soap as they both seem to have good results.  Any other info on flushing would be helpful as this is the first time I will have done it - vw's are pretty good in this country for not having crap in the cooling system from my experience.

One other issue is under full boost, (I have it set to about 14-16 psi for now) it will fluctuate between 14 and 16 psi going back and forth until I let off the go pedal a bit, then it stabilizes.  I have a manual boost contoller going to the boost can (-reversed vacuum can -vnt 17 turbo).  Will enlarging the leak hole in the boost controller reduce this, or would blocking the hole reduce in the manual boost controller reduce this?  I like to figure out how to stabilize this before I do any higher with boost.

[R.O.R-2.0]

i wouldnt be worried about running flush AND soap in my cooling system..

maybe even a little simple green.. that stuff is safe on every metal ive used it on, including al13, brass, copper, iron, stainless, whatever..

as for your boost reg problems, when i built my boost controller, i made my orifice bigger than recomended, because were running about twice the boost thru these than most people are.. my boost controller doesnt let my boost fluctuate at all.. im actually surprised at how well it worked..

[rodpaslow]

Do you remember what size of hole was in it?  The one in mine might be 1/32" if that.  I was just wondering if I need to go bigger for more bleed or smaller for less???

[Smokey Eddy]

Couldn't be too bothered to read the whole thread (sorry) but i run 25+psi on an AAZ and previously on a 1.6td MF block and i absolutely had to use an MLS metal head gasket and ARP studs (because they dont stretch) otherwise i would destroy a head gasket everytime i even saw the boost gauge go anywhere near 20psi.

[R.O.R-2.0]

Couldn't be too bothered to read the whole thread (sorry) but i run 25+psi on an AAZ and previously on a 1.6td MF block and i absolutely had to use an MLS metal head gasket and ARP studs (because they dont stretch) otherwise i would destroy a head gasket everytime i even saw the boost gauge go anywhere near 20psi.

ive been running a K24 on my car, with a n/a bottom end, T/D head, RE-USED head gasket, RE-USED bolts, and stock manifolds..

im running on the same gasket as when i bought my rabbit!

run 20-25psi boost all the time, and my gasket is still fine..

[rodpaslow]

I think it depends on a few variables - as far as boost.  I had to take the head twice, I had an oil leak into the coolant with the first head gasket (metal) pulled the head off a second time and used some sealant (hylomar) between block and head gasket and head gasket and cyl head.  I was just doing a coolant flush last night and stripped one bolt on the thermostat housing and now it's going to be a you know what, to change because I have to pull the injector pump because the top left hand bolt I can't get a wrench on because of the injector pump bracket!  I have a spare housing so it won't cost me anything, just about 4-5 hours to change....

[rodpaslow]

I've run it a bit more (again it's a vnt17) and I thinks it's capacity for boost is bit much for a 1.6.  I can have the vanes fully open and mash the throttle and it will hit 18 psi and climb fast until I let off.  In FAQ I read before, started by fspGTD had the same problem only he wasn't going as high of boost as I want.  I want 18-20 max and I've had it easily at 25 psi and climbing with the vanes fully open.  It is relatively fast climb like 3 seconds max to hit 25psi.  I think the only solution to this is what he did - add a proper wastegate to bypass the turbo to limit it.  I don't think anything else will limit boost properly.

[fatmobile]

I was just doing a coolant flush last night and stripped one bolt on the thermostat housing and now it's going to be a you know what, to change because I have to pull the injector pump because the top left hand bolt I can't get a wrench on because of the injector pump bracket!  I have a spare housing so it won't cost me anything, just about 4-5 hours to change....

  Pretty easy access, I'd helicoil the thermostat bolt hole before I'd go to all that work.

 

[rodpaslow]

It wasn't as bad as I thought, I changed the waterpump, I just cut a 3/4 deep socket I had and I was able to get the bolt out and then it was easy to change the back half of the water pump.  Like you said though, I bough some heli-coils to refurbish the one I took out so if I ever need it I can use it.  Theme of the story - use the torque wrench tightening the thermostat housing!

[rodpaslow]

Running it now I still have one other issue - After it's warmed right up and been running for a while, if I stop I can smell something that smells like it's burning- while idling at a stop light or stopped and idling.  I noticed there is a bit of blue smoke coming out of the tail pipe and it has a bit of that smell to it.  When I blew the turbo initially, the whole car smelled like that.   Is the hot exhaust just removing some of the oil in exhaust pipe(not likely?), or is the head gasket leaking again or turbo seals? (turbo is new has maybe 200 miles on it).  Engine has less than 20,000 mi on it since full rebuild.  What may be causing this?

I've double checked timing - it's a giles pump set at just under 1.00 (.99 approx in dial gauge)

[rodpaslow]

Got the using oil problem fixed - if you use a provent 200 and you have it dumping back into the oil pan above the oil level, it must have their check valve or it will pull oil into the engine like you wouldn't believe.  Once the check valve added it's not using any at all.

Tool it on a 500 mi round trip and the smell of the burning/burnt smell is gone.  It may have just been in the tail pipe and just needed to be pushed out the back.

It's still cold (about -7°c) and having a wee bit of starting problems, but I think it's needed a new battery for a while and a starter.  Glow plugs are fine.

So the head is fixed, I am going to add a actual turbo wastegate to control boost and will report after that's put on, in a week or two.

Thanks for the replies!

[rodpaslow]

I just thought I'd update - after honing and new rings, going back to a fiber head gasket, everything is back together and running well.  I had one cylinder before this job that wouldn't start working till after a minute or so of running.  New rings and proper head gasket has taken care of that.

I have the VNT 17 installed after taking it apart and all it needed was a good cleaning of the control and the turbine side had some cake of sooth on it that had started to restrict it from turning freely.  It's actually pretty easy to take apart, not as much vodoo as I thought!  I have also added a wastegate to control boost as it would overshoot to 30 psi + easily.  The wastegate and vnt control work nicely together.  I've been keeping it to about 10-12 psi until I break in the rings somewhat.  Just wanted to say thanks for all the posts & help.

[rodpaslow]

I do have one quick question the in IP.  How do you set the residual fuel properly?  Is it just a bit less so the idle doesn't hang?  It a Giles pump and I should have left it were it was.   I know where to adjust it, just not how it should be set.

[libbydiesel]

To set the residual pressure, I would disconnect the high idle/cold start linkage rod, set the idle lever to the slow idle position and run out that stop screw all the way so the slow idle lever is resting on the pump lid.  Then adjust the idle speed using the residual pressure screw until it is just below the idle speed you want.  Bring the idle up to the proper speed using the idle lever's slow idle stop screw.  Adjust the fast idle rod length.