Head gasket troubles, please help.

[frdtrckmnrich]

This is kinda long,
I got my 85 6.9 last fall . Earlier this spring (march?) i replaced the head gaskets (felpro),they were leaking to the outside of the block. I did not replace the head bolts. The heads were checked out and milled 5 thousandths. Put it back together and it was fine. In june i installed a used banks sidewinder non-wastegated turbo. After a few trips i started having coolant blow out of the overflow. I figured that since i didn't replace the head bolts that it blew another gasket. So i tore it down. Sure enough the coolant passage near cyl 1 had been blown from the cyl to the water jacket. There was no coolant in the cyl when i tore it down. I had the heads checked and they checked fine. So i purchased some arp studs, new gaskets (felpro), and reassembled torquing them to 85lb/ft after 3 steps. According to arp's instructions. I then went over them again at 85lb/ft. I installed the motor back in the truck today got it all hooked up. Fired it up, everything looked great. No leaks. Went for a small ride (less then 1 mile)and it started blowing coolant out again. Got it back home and there was tons of pressure in the radiator. It seemed like steam. So we pulled the radiator cap and the coolant was very low. All while the engine was still running and not overheating according to the gauge.Which i also double checked with an infrared temp gun. Head temps near the exhaust ports were around 180. We filled the radiator back up, this took ahwile up and down, up and down. Once we were comfortable we put the cap back on , mind you it is still running. Shortly after we realize it is ******* coolant out the back of the drivers side head. This is where it stands as i type this.

So now my ?

Is it possible that there was an air pocket that created steam. Which created lots of pressure forcing coolant out of the overflow and blowing another head gasket?

 

[Diesel JD]

I'd be suspicious that your problem might be something else such as the precups protruding too much from the heads like Zigg had with his setup, or you have block damage, or the block hasn't been cleaned thoroughly enough. There really can't be any gasket residue, oil or dirt on the block or head surface and if the precup protrudes beyond specs it will not seal right either.

 

[frdtrckmnrich]

Pre cups are good. I scraped the block thoroughly and the wiped it down with a brake clean soaked rag.

What kinda block damage would cause it to go from the front of one bank to the rear of the other?

 

[RLDSL]

What kinda block damage would cause it to go from the front of one bank to the rear of the other?

The first time you had a leak at #1, then after the studs, at the back of the head on the drivers side. Did you switch the heads when you put them back on? If so, a leak from a problem #1 would wind up right there.

When you put the heads on, did you have a cherry picker to gently lower them down and pilot studs to run them down to the gasket squarely, or were you having to muscle the things on? The slightest bit of shifting around while setting a head can ruin a new gasket.

-----------Robert

 

[f-two-fiddy]

What type of thermostat are you running?

 

[BigRigTech]

I would take the heads for a 2nd opinion, my question is this - was it the same head you had a leak on everytime? Did you put a machinist straightedge on the deck of the block? When I clean a block for a new head gasket I use 220 grit emery clothe to lightly scuff the block for good head gasket adhesion....Haven't had one come back yet. Did you use the ARP moly lube on the studs and did you torque them to factory or the ARP specs?

 

[frdtrckmnrich]

The first time you had a leak at #1, then after the studs, at the back of the head on the drivers side. Did you switch the heads when you put them back on? If so, a leak from a problem #1 would wind up right there.

When you put the heads on, did you have a cherry picker to gently lower them down and pilot studs to run them down to the gasket squarely, or were you having to muscle the things on? The slightest bit of shifting around while setting a head can ruin a new gasket.

-----------Robert

The heads were put back on the same sides. I'm sure of this because i never removed the temp sensors or heater hose connection.

The motr was out of the truck for assembly with the studs. Yes there were 2 studs in each head when i put them on.

 

[frdtrckmnrich]

What type of thermostat are you running?

Stock replacement- napa.

 

[frdtrckmnrich]

I would take the heads for a 2nd opinion, my question is this - was it the same head you had a leak on everytime? Did you put a machinist straightedge on the deck of the block? When I clean a block for a new head gasket I use 220 grit emery clothe to lightly scuff the block for good head gasket adhesion....Haven't had one come back yet. Did you use the ARP moly lube on the studs and did you torque them to factory or the ARP specs?

The original gasket replacement was because the heads were leaking coolant to the outside of the block. Then after the turbo is when i got the coolant blowing out of the overflow. I used 30wt oil when i put the studs in and torqued to arp's instruction sheet.

 

[BigRigTech]

Did you use the ARP moly lube on the nuts and the studs where they come through the head? 30W oil and moly lube will give you 2 totally different torques. Look at the factory specs VS the ARP specs....There is a difference due to the lubes used.

I still think you have a head issue though.

 

[frdtrckmnrich]

I used oil and torqued to arp's spec's when using oil.

 

[BigRigTech]

ok. JUst wanted to rule out an under torque issue.

 

[frdtrckmnrich]

I appreciate everything.
That's why i posted cause nothing makes sense to me. I've been running it over and over in my head trying to figure it out.

 

[BigRigTech]

I scanned up a couple of pages from my Factory 7.3IDI manual regarding torque specs and sequence, compare it to what you've done to see if there are any differences. This book came from a fellow tech who work for IH for 25 years. I can email these to you if you can't read them.

You must be registered for see images

You must be registered for see images

 

[frdtrckmnrich]

That says that the head bolts should have been torqued to 100lb/ft. Arp's instructions say 85lb/ft.

What would you do? 85 or 100 ?