Need recomendations please

[RustyToy]

Dealing with my '90 Jetta 1.6NA here. Just finished changing the HG, milling the head,new injectors, water pump, and thermostat. I did all this because it blew the headgasket.

Put it all together, followed the torque specs to the letter. Timed the pump by the book. so I drive the car to work last tuesday and everything is great. Temp guages (I have the factory one and an aftermarket) are hanging right where i want them, all is good with the world.

Until....

The drive home.  I got stopped in a construction zone on a hill for 15 minutes. temp guages holding steady, no problems. Then all of a sudden it's thermonuclear meltdown. Steam from the engine compartment,smoke from the exhaust and engine is running rough. There is zero shoulder here so nowhere to pull off. I have no choice but to chug to the top of the hill just past the flagger and shut it down next to the spot they had cleared for him to park his truck.

I called the wife and 45 minutes later my truck and trailer is there to 'rescue' me.The next night I add some water and start it up. There are engine gases coming from the overflow tank. I can see where the water is leaking from though. The distribution neck that bolts on the end of the head has cracked. (cheapo plastic piece)

Now, with that being said. I had not got to the 1000 k torque stage yet. Does anybody think there is a chance that if i complete the last torque sequence it might seal up?

If not, should I go ahead and buy new bolts with the HG even though I have not fully 'stretched' them yet?

I'm really getting tired of doing HGs on this car, if I can get away with it i'd rather not do it.

Any thoughts from those who know better than me?

[ORCoaster]

Well in my pea brain the 1000 K mark is all about resetting the work after vibration has had time to work on it.  Yours has not had that.  So I would be inclined to fix that crappy leaky front spout, connect everything up good and tight by loosening and re-tightening the head and refill with a 60/40 mix of antifreeze and water.  Then I would let it cycle the thermostat open a few times, open the heater valve and let as much air out of the system as you can.  Then let it all cool down and note how much or how little the level in the coolant tank changes. 

Once you get to the magic mileage, do the re-tighten.

Unless you got it so hot that things went all warpo on you I can't see tearing it all down again just to do what?  Tighten it up?  Or do you think you need to replace the HG now? 

My thoughts are that you had coolant problems from the leaky neck and that caused the overheat which then caused the head to lift or warp.

[Toby]

Loosening and retightening the head bolts isn't going to do anything but ruin what might be a good head gasket. You have already run the TTY bolts past their elastic limit. I would check all of the bolts for tightness and drive it. I might even put the next 1/4 turn on them. Then you will know for sure.

[ORCoaster]

Toby, do you think the last 1/4 turn on the bolts will give him a solution to what he stated in his post?

"There are engine gases coming from the overflow tank."


That is why I thought he needed to release the tension and reset it all.  Many have used bolts again and again so are new bolts needed at this point?

[Toby]

The reason they were used "over and over again" is that they won't hold a head gasket if you try to reuse them when they are stretched past their elastic limit. They never have the same clamping force again.

Either the HG is toast or its not. Loosening and retightening the TTY head bolts is not going to cure anything once they have been stretched. Another 1/4 of a turn or 2 (depending on where you were in the sequence) will tell you all you need to know. Most likely the HG is toast, but I once bought a Rabbit diesel pickup that had a "bad head". The motor was freshly rebuilt but they never put the stretch on the bolts and sent it out the door. Back in 100 miles for blowing the coolant tank apart. I got it for $500. Took it home and checked the head bolts. Guess what? Just barely tight, no stretch. Retorqued the head and put on the stretch and it ran great with no coolant loss or combustion gasses in the cooling system. Drove it for a while and sold it for $3600. Did not even vacuum it out.

[nathan_b]

thats why you dont mill heads unless theyre warped.

if it aint broke...

[BigVWman]

Not Supposed to mill VW heads at all especially if warped! We all skim a little here or there but it is a no no!
You have nothing to loose by trying to tighten it and see, i would say its a crap shoot though. I have had a few seal a few not. I didn't think the stretch bolts had an additional tightening step after run?

[Toby]

thats why you dont mill heads unless theyre warped.

if it aint broke...

Actually warpage is not a big deal, especially with an aluminum head. Just install it as is. When you heat cycle them a few times most of the warp goes away as long as they seal. The real reason to surface a head is when you have "divits" (small notches or low spots) in the surface that will not allow it to seal. No way around surfacing then.

FWIW, I have been surfacing warped/chowed OHC heads for 30 years and have never seen a bad outcome. It seems obvious that you should have trouble with cam bore alignment after a head surface, but it just never seems to be a problem.

[BigVWman]

I always figured there was a big difference between surfacing for a good gasket seal surface and the removal of enough material to remove a warp! I too have bolted up warped heads way beyond what bentley says is acceptable and never had an issue. The result of milling a warped head may not be evident for many miles, quicker wearing cam bearing surfaces and lower oil pressure. Besides don't the modern cylinder head guys use heat in a big oven to take out a warp?

[nathan_b]

valve protrusion and pre comb chambers are also vulnerable when skimming.

[RustyToy]

Never heard that about milling the heaads before. It was warped beyond my comfort so I followed my standard routine. Mill it.
The machinist who did my head has been doing my heads for 20+ years and has done many many VW Diesel heads. He didn't think it a bad idea to do it. I'll have to ask him about that.

I'm going to go ahead and give each one of the bolt an additional 90* ( final torque) and hope for the best. Hey, it cost me like $36 for head gasket and new bolts. Small price to pay to do it right.

Probably won't be till sunday though. I have many other irons in the fire till then. If anyone has more thoughts on this keep them coming. I appreciate all the input I can get.

[ORCoaster]

Based on what I read here you have nothing to loose and all kinds of stuff to gain by investing in a little wrench work. 
Thanks for all the input guys.

We learn a bunch from each other.

[RustyToy]

Pull up a seat for a long read. I'm recounting yesterdays events hoping it will lead someone to a clue that I've overlooked.

Well, I got the chance to spend some quality time with the jetta yesterday. An extra 90* on each of the headbolts brought the exhaust gases in the reservoir to a halt.
That was good news.
I fired it up and let it idle for nearly an hour and the temp never got higher than 'normal'.

Now, I've got two temp guages in my car. One is the factory guage and the other is an aftermarket guage with the probe in the line going to the heater core.

So After nearly an hour of idling I pushed the car back to look at the floor under the car. Zero water on the floor at this point.

So now I decide to pull it out and go for a short drive. Back the car out and onto the road. 3/4 mile down to the highway. Ease on out and run through the gears. everything looks great temp wise so far. I'm doing 70 before I know it. Slow it back down to 55 and head down the road. About 2 miles down the road I come to a long steep uphill grade. Everything is fine till about 75 feet from the top. The factory guage starts climbing and the after market shoots from 190 to 220 instantly.

Turn around and head back home. The temp guages come back down to an acceptable level about 1/2 way down the hill.

Get back to the house and the light starts blinking.

Let it cool off for about 2.5 hours and check coolant. Res is empty. Fill it back up and start car. As it sucks it down a little at a time I top it off. Car's idling fine, factory temp guage is sitting between 3/4 and 1/2...But, heater is blowing cold. I can see water circulating when I pull the cap off, the engines warm. I can touch any hose and they're hot with the exception of one of the hoses coming from the heater core.

I reach over and pull the throttle and with the rise in rpm coolant starts coming out of the hole in the side of the res. let off and it stops. flip the throttle and it pukes again.

So, can anyone out there tell me why it's doing this? Is it possessed? is there a devilish little gremlin in there playing jokes on me or am i missing something?

[ORCoaster]

Let me understand this statement:

I reach over and pull the throttle and with the rise in rpm coolant starts coming out of the hole in the side of the res. let off and it stops. flip the throttle and it pukes again.

So, can anyone out there tell me why it's doing this? Is it possessed? is there a devilish little gremlin in there playing jokes on me or am i missing something?


Do you mean that while it was on the idle there was no water going into the reservoir tank?  And when you raise the RPMs it does?  I thought you had water recirculating prior to flipping the throttle. 
My thought is that you have an air trap in the heater core.  Or a poorly performing water pump.  Pulling the hill and increasing the temps twenty degrees is what mine does all the time.  The instantly jumping thing you describe makes me think of low fluid in the line then all of a sudden getting some up to the sensor,  a burp, a bubble, a better point of pumping? 

When I refill the coolant I cycle the heat level back and forth and make sure heat is pouring out the defroster to verify the core is full.  After I have such a coolant problem as yours I pack a gallon of antifreeze with me for awhile.  Seems to take a mine a few cycles of real hot to full cold to settle down to a normal level in the system.

[rabbitman]

I say your water pump has issues, it should always be puking coolant into the coolant tank.