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View Full Version : bad headgaskets plus boost = ?



Sundance 6g72
11-18-2011, 02:02 PM
soo im pretty sure my headgaskets where bad while i was NA. Coolant always looked like hell and i think i had some white smoke going on sometimes.

anyways, while NA, if i beat on the car alot i would find a little coolant had escaped past the radiator cap. Nothing big though. Now with boost.. its a different story. The reserve seems to fill up no matter what (even if i keep it empty.. after a hard run, its full)

so my test went like this. i have a boost leak so i took advantage of it. with the wastegate connected to the turbo compressor outlet, i was limited to about 2-3psi. combine 2-3psi with an empty reserve and full coolant system and you get a relatively stable system. my cap still let a little coolant past but nothing huge and after the run the reserve was almost full but it never overflowed.

now with 5-8psi, its a different story. After a few hard pulls i lose alot of coolant.. sometimes the cap gives and it sprays all over and the reserve is deff full and leaking.

now take this into account, the coolant temp rarely goes above 230. i have a 50/50 mix just about so it should not be boiling over. the theory is that bad headgaskets let air pressure into the coolant system and force my coolant out. my temp gauge proves this too because its always busy moving about from cool to hot.

i have two new MLS headgaskets that i can install and probably should, but ill have to wait until my school papers are done, that will take priority.


does anyone have anything to back this up? or maybe a different idea of whats going on. cant see how i would be wrong though. the amount of coolant blowing out of the system seems to be related to the amount of boost i run.

---------- Post added at 01:02 PM ---------- Previous post was at 12:57 PM ----------

on a side not.. my wastegate was almost half open 100% of the time. adjusted the arm and its better.. i can build boost at part throttle and really nail it at full throttle. its still laggy but i kind of like it. 1st gear dosnt need boost and by the time it gets there i jump into 2nd.. i dont lose much between shifts either so im satisfied. as long as i can get rid of this coolant explosion with boost then ill be good.

turbovanmanČ
11-18-2011, 02:06 PM
Yes, you have bad gaskets, your simply pushing air into the cooling system and it has to go somewhere. If your going to keep driving it, I would put a lower pressure cap on or run as little boost as possible otherwise you can blow your rad, heater core or hose.

c2xejk
11-18-2011, 02:16 PM
Have you checked your headbolt torque?

When you replace the headgaskets, have the heads milled for flatness and to clean the mating surfaces...

Sundance 6g72
11-18-2011, 02:40 PM
Havnt checked headbolt tq... They are factory bolts, factory headgaskets


Headbolts can be resused right?

I can keep the wastegate open to keep boost at 0.

Ill deff have the heads checked for flatness

bond_bbs
11-18-2011, 02:50 PM
Yup, you can reuse our headbolts. Just be prepared to find an allen socket, and short extension. Cannot remember the size.

Sundance 6g72
11-18-2011, 03:06 PM
Yeah ive removed heads before... It takes a big allen socket.

What is the head tq sequence? I think brent has a pic of what he does in his thread thst ill check later

---------- Post added at 02:06 PM ---------- Previous post was at 01:58 PM ----------

Got an estamite for checking and milling the heads... $120. I guess thats not bad but im broke. I cant emagine the heads are warped cobsidering the gaskets where bad before i boosted the motor.

turbovanmanČ
11-18-2011, 03:35 PM
[/COLOR]Got an estamite for checking and milling the heads... $120. I guess thats not bad but im broke. I cant emagine the heads are warped cobsidering the gaskets where bad before i boosted the motor.

They might be tad warped but I find they like to get pitted. Cheap insurance to have them milled.

MC#4
11-18-2011, 04:27 PM
Sounds like head gaskets to me. My car just blew one a few weeks ago. I hooked my cooling system pressure tester up and it would build up to almost 20psi when running. I'd get the white smoke on acceleration off a stop. My number 1 spark plug was wet too. At this point though, I am assuming head gasket but In reality it could be a cracked head. I'd have the machine shop pressure test your heads for cracks if they don't do it right away with a mill job. If you haven't had the heads redone before, you may consider a fresh valve job and everything. I haven't been following your build very closely so I'm not sure what's been done before.

87turbodance
11-18-2011, 05:08 PM
Head bolts take a 10mm hex

Sundance 6g72
11-18-2011, 05:32 PM
Sounds like head gaskets to me. My car just blew one a few weeks ago. I hooked my cooling system pressure tester up and it would build up to almost 20psi when running. I'd get the white smoke on acceleration off a stop. My number 1 spark plug was wet too. At this point though, I am assuming head gasket but In reality it could be a cracked head. I'd have the machine shop pressure test your heads for cracks if they don't do it right away with a mill job. If you haven't had the heads redone before, you may consider a fresh valve job and everything. I haven't been following your build very closely so I'm not sure what's been done before.

20psi while idling :confused: damn.. i hit 6000rpms with 8psi of boost!!

well heres the deal, i have a set of spare heads.

right now, my current heads have bad valve stem seals OR the guides have dropped. mine should be c clipped so im saying its the seals. Im going to pull these heads, mill them if they arnt flat, re install them with fresh stem seals and mls headgaskets

down the road, my spare heads will be self ported (mainy cleaned up) cammed, new valve, guides, springs, and rev to like 8000rpms.. so i dont want to spend to much time on the current heads.

turbovanmanČ
11-18-2011, 06:24 PM
20psi while idling :confused: damn.. i hit 6000rpms with 8psi of boost!!
.

No, no, no, lol, he put a pressure tester on the tested the system at 20 psi.

Ondonti
11-19-2011, 12:50 AM
If you can't afford it but can afford gaskets, just clean and reassemble. I have gotten away with it many times, even on a head that pushed massive coolant on big power. Copper Spray. You can always straight edge the head and block to make sure but its probably just the fire ring on the gasket failed. Same thing that probably happened to my Spirit. I ran for 5 years on a bad headgasket until my 2nd 2000 mile trip towing another car. I didn't make it the last 120 miles.

Sundance 6g72
11-19-2011, 01:54 AM
You know brent, i might go that route. I already have headgaskers and valve stem seals...

I reallly doubt the heads are warped or need milling done... Ive bounce off the limiter many times but only when na... 147hp at work

Ondonti
11-19-2011, 02:05 AM
Doing that surface prep is best practice but when you are broke you would rather fix it again then spend money you didn't need to.

Sundance 6g72
11-19-2011, 02:14 AM
I guess ill make my decision when i see whats going on

only thing im worried about is tq sequence and getting it right

Sundance 6g72
11-19-2011, 04:49 PM
yeah thats what i meant. my bad

heads are off. the front headgasket looked fine. the rear one came off WAY TO Easily.. i just pulled it off the head as if it had copper spray on it.

cyl 5 looks questionable (it looks fine but has signs of coolant being in it?)

rear headgasket had some damage on the edge but not that would allow coolant into the cyl? ill have to check the corner of it.. ill bet money its right next to cyl 5

have to wait till monday im pretty sure in order to get a nice valve spring compressor so i can take care of valve stem seals while the heads are off.

http://a3.sphotos.ak.fbcdn.net/hphotos-ak-ash4/386069_10150468007373899_534573898_10267685_662549 593_n.jpg

http://photos-g.ak.fbcdn.net/hphotos-ak-ash4/384942_10150468008108899_534573898_10267687_150185 0071_a.jpg

http://a8.sphotos.ak.fbcdn.net/hphotos-ak-snc7/385921_10150468008583899_534573898_10267688_502339 19_n.jpg

http://a5.sphotos.ak.fbcdn.net/hphotos-ak-ash4/380438_10150468009043899_534573898_10267690_927307 302_n.jpg

http://a7.sphotos.ak.fbcdn.net/hphotos-ak-ash4/383262_10150468009743899_534573898_10267693_119776 4060_n.jpg

http://a1.sphotos.ak.fbcdn.net/hphotos-ak-snc7/310397_10150468010613899_534573898_10267699_104471 5345_n.jpg

Sundance 6g72
11-20-2011, 04:45 PM
http://a1.sphotos.ak.fbcdn.net/hphotos-ak-ash4/380233_10150469924443899_534573898_10276705_830613 025_n.jpg

so once the heads are Torqued to 90ft lbs, back off a 1/4 turn and then go back to 90?

do i run the motor and then re tq the heads?

Ondonti
11-20-2011, 11:54 PM
No, you retorque right away. Do you have the chart for order? I believe i posted that at some point.

The purpose of the steps is to clamp the head down evenly. The purpose for backing off 1/4 turn and going 90 is that your actual bolt clamp loads will not be as consistent when you make small steps. Ever had a bolt not turn but your wrench click? This means you didn't achieve torque properly. At work we are required to reach final torque while the nut or bolt is turning. You get the head perfectly clamped down then back off one at a time 1/4 turn and back to 90 while all the other bolts are tight holding the head down.
If you don't want to go all the way to 90 and don't want to back off 1/4 turn, you still need to do that if on your final step the wrench clicks without anything turning. If it fails to move, you need to back off and then go to final torque (but you don't need to do steps if all your other bolts are fully torqued).

This is the proper way to do it but that doesn't mean I have not gotten away with just 80 pounds and no fancy stuff. This is meant for the MLS headgasket but I used this technique on the Felpro.

I have never retorqued a headgasket. ARP studs or the base quality often need it because they stretch (crap).

Sundance 6g72
11-21-2011, 10:08 AM
So 90 is safe for re using headbolts?

I get it now. So i dont loosen all the bolts in order... I loosen and re tq each bolt one at a time?

My order is in my manual at home

bond_bbs
11-21-2011, 01:00 PM
The order, which is off the top of my head goes like this if I remember correctly: this is while looking AT the head

(5)(1)(4)(8)
(6)(2)(3)(7)

As said - I'm going from memory, but I think that's the order the Haynes shows.

Sundance 6g72
11-21-2011, 01:21 PM
its all good. i have the book that tells me

i just want to make sure im tightening correctly

once i have them tightened down like the picture says ^ ^ ill loosen bolt 1 by .25 turn and then tighten it to 95lbs. then do the same with bolt too

at first i was thinking we would loosen all of them by 1/4 turn and then re tq to 95 but doing one at a time makes much more sense.

turbovanmanČ
11-21-2011, 01:39 PM
That isn't copper spray, that's rust and yeah, those head gaskets are done, quite easy to see where is was leaking.

I would seriously consider spending the few bucks and getting them planed.

c2xejk
11-21-2011, 01:41 PM
The reason for the loosen 1/4 turn is because static friction is greater than dynamic friction and the spec is given assuming the bolt is in motion (ie. dynamic.) As far as bolt reuse, stock 3L bolts are fine for reuse because they are not Torque To Yield (aka TTY.) If you can it is a good idea to chase the bolt holes to clean the threads.

And you know to oil the threads, right.

turbovanmanČ
11-21-2011, 01:56 PM
And you know to oil the threads, right.

And put some lube, IE ARP Moly lube, under the bolt head/washer to stop or reduce stiction.

Sundance 6g72
11-21-2011, 02:03 PM
That isn't copper spray, that's rust and yeah, those head gaskets are done, quite easy to see where is was leaking.

I would seriously consider spending the few bucks and getting them planed.

when did i mention copper spray? i said the rear gasket came off as if it had copper spray used on it (i remember brent saying he loves that stuff because headgasket removal is a sinch)

as far as rust on the deck, there is non.. there is some gunk that had to be cleaned up but nothing thats horrible. coolant passages dont look great but nothing i can do about that right now. as far as quite easy to see where its leaking, care to share? the fire rings (is that what they are called?) are all intact.. hard for me to see how coolant got in there but what do i know?


The reason for the loosen 1/4 turn is because static friction is greater than dynamic friction and the spec is given assuming the bolt is in motion (ie. dynamic.) As far as bolt reuse, stock 3L bolts are fine for reuse because they are not Torque To Yield (aka TTY.) If you can it is a good idea to chase the bolt holes to clean the threads.

And you know to oil the threads, right.

yes to oiling threads and ive been working on a way to clean the threads. they arnt that bad in there but i know, we want them spotless.

turbovanmanČ
11-21-2011, 02:13 PM
when did i mention copper spray? i said the rear gasket came off as if it had copper spray used on it (i remember brent saying he loves that stuff because headgasket removal is a sinch)

as far as rust on the deck, there is non.. there is some gunk that had to be cleaned up but nothing thats horrible. coolant passages dont look great but nothing i can do about that right now. as far as quite easy to see where its leaking, care to share? the fire rings (is that what they are called?) are all intact.. hard for me to see how coolant got in there but what do i know?



I was saying you said that but to me the copper spray look is rust.

Look for black area's on the gasket, that's where its leaking. If I was good at modding pics, I'd circle the area's, lol.

Sundance 6g72
11-21-2011, 02:27 PM
if your talking about that, thats an effect from the flash. the rust looking area is actually silver like and pretty clean, just like the other deck. not sure how it turned out looking like that but whatever

ive never done a headgasket before, so if the area that was black gunky looking is a leak then i guess i had a few of those. thats good news i guess, i was hoping to find something wrong so i know im fixing it.

http://a8.sphotos.ak.fbcdn.net/hphotos-ak-snc7/385921_10150468008583899_534573898_10267688_502339 19_n.jpg

bond_bbs
11-21-2011, 02:34 PM
If you're not going to get the heads milled, take a razor blade from a utility knife (Just the blade!) and make sure there is no gunk or left over gasket pieces on both the head and the deck. Be gentle, and a fresh razor blade CAN cut off little pieces of steel / aluminum if your angle is too steep. You almost want to slide it parallel to the deck.

Sundance 6g72
11-21-2011, 02:56 PM
yep i have done all the surface prep.

im about to get a valve spring compressor from my buddies shop.. so the heads *should* be back on today.

if i could afford to get the heads milled, i would. but i cant.. i would have to wait a little bit and i need this car as soon as possible. If that ends up biting me in the rear then so be it, live and learn.

vss should be a sinch to replace right?

Sundance 6g72
11-21-2011, 03:46 PM
im trying to remove the valve springs

i can get the spring completly compressed.. but the valve and lock/retainer goes down with the spring.....

Ondonti
11-21-2011, 04:17 PM
Hit the retainer with a socket and hammer first to get them loose. THen you need to put pressurized air in the cylinder to keep the valve up. I couldn't get my locks to pop loose until I hammered each one, even with 130psi.

I have gotten away with reinstalling 10 year old OEM gaskets that have sat for 3 years in a shed by simply copper spraying and then heating the motor up and cooling it down (was leaking coolant when I first filled it up). When you use a new gasket like you should, you will be fine. You can always take a straight edge and feeler gauges to check the surfaces for out of flatness. There is a tolerance for that. Our cylinder heads flex before the headgasket actually fails so removing any material is worse then trying to have a perfect surface. I emphasize this because you are boosted. That said, if your cylinder heads are flexing, you are knocking, so flex is saving your motor.

c2xejk
11-21-2011, 05:23 PM
im trying to remove the valve springs

i can get the spring completly compressed.. but the valve and lock/retainer goes down with the spring.....

I take it you are using a "head on engine" type valve spring compressor, then you are going to have to do what Brent said. Might be able to compress the spring and then give the compressor a tap with a hammer. It is helpful to use a magnet to fish the locks out.

On the VSS, you can use a socket if you don't have the right tool.

Sundance 6g72
11-22-2011, 02:55 AM
[QUOTE=Ondonti;869524]Hit the retainer with a socket and hammer first to get them loose. THen you need to put pressurized air in the cylinder to keep the valve up. I couldn't get my locks to pop loose until I hammered each one, even with 130psi.

I have gotten away with reinstalling 10 year old OEM gaskets that have sat for 3 years in a shed by simply copper spraying and then heating the motor up and cooling it down (was leaking coolant when I first filled it up). When you use a new gasket like you should, you will be fine. You can always take a straight edge and feeler gauges to check the surfaces for out of flatness. There is a tolerance for that. Our cylinder heads flex before the headgasket actually fails so removing any material is worse then trying to have a perfect surface. I emphasize this because you are boosted. That said, if your cylinder heads are flexing, you are knocking, so flex is saving your motor.[/QUO

TE]

I predicted that the head gasket was bad before i got boosted. Air in coolant always, coolant always look like hell too. With boost i filled the coolant with air alot faster and saw the effects easier

At 8psi my intake temp never got hotter than 38* F and with how rich i was plus my lower timing, i dont think i was knocking... 93 octane.

Heads re installed, motor timed. Just need crossover on, upper intake on, belt, strut bar and i think im good

Vss did not get done. This is a story for later.. and im not to worried about it right now.

Ondonti
11-22-2011, 04:28 PM
Well it was no surprise to me that 4000 miles of towing cars completely blew a slow leak headgasket. Stupid Mountain passes. Thats why I don't worry so much about 3.0 mechanical reliability.

87turbodance
11-22-2011, 06:07 PM
........... :)

turbovanmanČ
11-22-2011, 08:56 PM
Is it done yet? :eyebrows:

Sundance 6g72
11-23-2011, 12:18 PM
yeah heads are on, builds 8psi and all seems good. i havnt loooked at it TOOO closely though.