Head Gaskets?

[BMFB]

Re: Head Gaskets?

Although not the same, and i'm considered crazy. I recommend running normal run of the mill head gaskets with a decent set of bolts/studs.

I play around alot with 3800's, and I ran MLS gaskets for years. I am back to running stock head gaskets. I have never blown a head gasket from power myself. My series 2 3800 on stock gaskets has seen 28psi, and in my 4x4 awd blazer has gone 10.20's

 

[mattw]

Re: Head Gaskets?

Although not the same, and i'm considered crazy. I recommend running normal run of the mill head gaskets with a decent set of bolts/studs.

I play around alot with 3800's, and I ran MLS gaskets for years. I am back to running stock head gaskets. I have never blown a head gasket from power myself. My series 2 3800 on stock gaskets has seen 28psi, and in my 4x4 awd blazer has gone 10.20's

I ran stock parts store variety head gaskets on my old Typhoon. I think they were felpro but I can't remember. I ran them for YEARS at 16+ PSI with no issues. I agree with you 100%.. Prep the surfaces properly, torque your bolts properly, almost any head gasket will work...

 

[Damian]

Re: Head Gaskets?

I used that felpro gasket on my new build. Was recommended by the builder.. The engine isn't installed yet but should be next week..

Those are it. I think they are great, especially for the $25 each price.

 

[Peter]

Re: Head Gaskets?

As I recall, the bore holes in the Felpro head gaskets are not perfectly round, and are quite a bit larger than the cylinder bores themselves. I don't know how much difference that makes in the real world. I do like the price.
On the other hand, the Cometic MLS can be purchased for a specific bore diameter, such as 4.060, and the thickness adjusted to obtain the desired squish.
I thought that was important since my block was decked slightly to true it up, and bored .040 over.

 

[Neelsonwheels]

Re: Head Gaskets?

Little update!!
I went with MLS gaskets,sprayed both sides with copper spray,Permatex high performance teflon thread sealant. torque 25lbs then 50 lbs then to 70 lbs. I installed the lower intake last night along with the Exhaust headers. Might I say that the stock exhaust manifolds absolutely kicked my ass!! I cannot express how much they sucked. I am in the process of setting the valve lash. I have never done this on an automobile before so I am learning. I have done it a boat load of times on my motorcycles.I am hoping to get it all buttoned up today and run it. I'll post the outcome good or bad!!

 

[mattw]

Re: Head Gaskets?

Smart choice. Did you oil the bottom of the head bolts b4 you torqued them?

 

[Neelsonwheels]

Re: Head Gaskets?

Yes sir I did. Between the bolt head and washer and between
The washer and head.

 

[Damian]

Re: Head Gaskets?

Little update!!
I went with MLS gaskets,sprayed both sides with copper spray,Permatex high performance teflon thread sealant. torque 25lbs then 50 lbs then to 70 lbs. I installed the lower intake last night along with the Exhaust headers. Might I say that the stock exhaust manifolds absolutely kicked my ass!! I cannot express how much they sucked. I am in the process of setting the valve lash. I have never done this on an automobile before so I am learning. I have done it a boat load of times on my motorcycles.I am hoping to get it all buttoned up today and run it. I'll post the outcome good or bad!!

Which ones? The Felpro ones I posted are MLS, just like the Cometic ones.

 

[Neelsonwheels]

Re: Head Gaskets?

I went with the Fel-pro gaskets. We will see. Thanks Damien.

 

[Damian]

Re: Head Gaskets?

The Felpro gaskets have a coating on them, and I don't think you need anything on them to help seal. I didn't use anything on mine.

Either way, I hope they work for as good as they work for me.

 

[Ls10]

Re: Head Gaskets?

sorry to bring up an old thread. but it says those felpro mls gaskets are a 4.125 bore....isn't that huge for a 4.030 bore

 

[liquidswords88]

Re: Head Gaskets?

I did quite a bit of research on head gaskets for my typhoon rebuild. From what I found a head gasket that has a bore that is larger than the cylinder bore is not a problem. Some people say .010 is ideal. Others say it depends on the type of gasket and combustion chamber design. The only thing I found that was agreed upon by all, was that the fire ring can not protrude into the combustion chamber. All you end up with, when you have a larger bore head gasket is a little extra "dead space".

 

[Ls10]

Re: Head Gaskets?

yeah .010 is ideal. those felpros are 0.95 diff

 

[Mephisto]

Re: Head Gaskets?

Absolutely stupid question here... and only because I've yet to dive into this project, but are you guys replacing the head gaskets without pulling the motor?

I've yet to find a shop that will do this job for under $4k (which I'm sure is their way of saying they don't want to do it). In theory I should be able to leave the motor in and just pull the fenders/hood off so I'd have more room to work? ...but that's also predicated on the fact that the block isn't FUBAR.

Just trying to get an idea of how much of a pain in the ass this is gonna be BEFORE I start tearing it down.

 

[RealFastV6]

Re: Head Gaskets?

Absolutely stupid question here... and only because I've yet to dive into this project, but are you guys replacing the head gaskets without pulling the motor?

I've yet to find a shop that will do this job for under $4k (which I'm sure is their way of saying they don't want to do it). In theory I should be able to leave the motor in and just pull the fenders/hood off so I'd have more room to work? ...but that's also predicated on the fact that the block isn't FUBAR.

Just trying to get an idea of how much of a pain in the ass this is gonna be BEFORE I start tearing it down.

I've never pulled them in the truck for any reason.

Generally speaking... head gaskets "go" in these trucks AFTER you've done damage to the bottom end, not before. I wouldn't say it's common for folks here to pull heads and do the gaskets with the engine in the truck because unless you're just pulling the heads to change them, then the head gaskets are usually a part of a larger R&R.

 

[Sean Krupa]

Re: Head Gaskets?

Here is when I was replacing the stock heads with Vortec heads with motor in
http://www.syty.net/forums/showthread.php?t=79530&page=14

 

[Anarchy99]

Re: Head Gaskets?

I don't necessarily think you've done bottom end damage if the head gaskets go. I'd need to see more proof before saying that was a fact. My passenger head gasket blew, bottom end looks almost brand new. They can be done in the truck but it's just easier to pull the motor.

 

[Don W.]

Re: Head Gaskets?

I've pulled the heads at least twice with the motor in the truck. Torqueing the heads and getting a proper seal on intake/block interface is maybe the hardest part. Everything else is just wrench time. If you're worried about bottom end damage cut open the oil filter and check for metal.

 

[Mephisto]

Re: Head Gaskets?

I don't necessarily think you've done bottom end damage if the head gaskets go. I'd need to see more proof before saying that was a fact. My passenger head gasket blew, bottom end looks almost brand new. They can be done in the truck but it's just easier to pull the motor.

The cliff notes on what happened would be...
truck has ext wastegate, turned boost down to 10psi trying to get truck to run with 0 knock before bumping up the boost.

One day i start the truck and the idle goes up to 3k rpms and stays there, CE light comes on, and after a few minutes the truck regulates itself back down to normal idle and the CE light turns off, everything is fine after. This progressively got worse and worse to where the idle wouldn't go down, even if I drove the truck.

OK, must be the MAF sensor, replaced that... no change, took it back and got another one, just to make sure... no change.

Exhaust is puffing steam and smells like coolant, and coolant overflow is empty, but temp gauge holds at 180*.

Stop off at my parents one day, refill overflow, and let the truck cool down. Hour later, I start the truck, idle goes up to 3500 and stays there... no CE light. After 5min of idle at 3500 and no change, I back out of the driveway get a few hundred feet down the street and there's no power, I pull over, and the truck stalls out. I start the truck and the idle is rough, turn around and head back to my parents house and there's no power.

Eventually limp it back to my house, and check compression with one of those spark plug type gauges. 0 compression in 1 & 2 cylinder, all others are normal.

Even when I had a motor with blown rings I got SOME reading on the compression tester in all cylinders. Seems odd to get 0psi in 1 cylinder on each side and full psi in all the others. Also, when the truck is idling, there's no smoke puffing out when I remove the oil filler cap... I know that's not a definitive way of checking for blown rings, but you'd think there'd be smoke coming out somewhere if that were the case. I can bust open the oil filter and see if there's anything in it, but I don't think I'll find anything.

I once convinced a girl that because of the curvature of the earth, you actually get better gas mileage driving south because you're essentially driving "down hill". :lol: However, I feel about as dumb as her when it comes to the intricacies of cylinders vs heads with these trucks.

 

[wildphil]

Re: Head Gaskets?

I am no expert on this subject. But I will post what my thoughts are. And they may be totally wrong.

My thinking is if you are getting 0 compression that you would have a hole in your piston. I don't know if possibly a head gasket blown out say to the outside of the engine from cylinder 1 and 2 could cause a 0 compression reading or not. I have never had this issue. But I would think if this happened you would have coolant/oil flowing from this spot.

I would think if you have a head gasket blow out between cylinders. I would think you would get a compression reading. But they may be a lower reading. And both of those readings would be almost the same compression reading.

Again this is just my thoughts so I could be totally wrong.