1G Boosted Coolant leak

[all black 4G63]

So after a test pull on the street @ 26-30 Psi to 7000 RPM 43db knock (Haltech elite) on 93 I noticed evidence of coolant on the transfer pipe which looks to be coming from the water/pump o-ring to pipe connection. (See photo).
I’m not sure if I should be concerned about this, but I kinda am and it’s because…..
I recently over boosted my engine and blew all my freeze plugs out and noticed the coolant on the transfer pipe then as well…
So I replaced the head gasket with EVO MLS and used L-19s torqued to 105lb ft and then re-torqued after a couple heat cycles. The head was measured for flatness and was within spec.

Anyone have any experience with this? It is a Ravens Fab transfer pipe btw.

You must be logged in to view this image or video.

You must be logged in to view this image or video.

 

[97egl]

Just because the block is flat doesn't mean it has the correct surface finish to run an MLS gasket. MLS gaskets won't seal against rougher cut surfaces that composite gaskets will. If you are running 30 psi with headstuds you have no reason to use an MLS. Composite will hold up just fine at that level.

 

[all black 4G63]

Just because the block is flat doesn't mean it has the correct surface finish to run an MLS gasket. MLS gaskets won't seal against rougher cut surfaces that composite gaskets will. If you are running 30 psi with headstuds you have no reason to use an MLS. Composite will hold up just fine at that level.

i see, however 30 psi is just closed loop boost control on 93. The car is E85 ready just not today. The idea is to run way more than 30psi. I’m just not sure what’s going on here with that coolant spray. The head and block were recently machined.

 

[97egl]

i see, however 30 psi is just closed loop boost control on 93. The car is E85 ready just not today. The idea is to run way more than 30psi. I’m just not sure what’s going on here with that coolant spray. The head and block were recently machined.

Ah ok. Did the machinist know you were going to use an MLS gasket?

A leak in that area would almost have to come from the head gasket unless the o-ring on the coolant pipe was leaking but I would think that would if it were an issue with the o-ring you would see it spraying out once the system held pressure.

You could put some dye in the coolant and then try to trace the source of the leak with a black light.

 

[all black 4G63]

Ah ok. Did the machinist know you were going to use an MLS gasket?

A leak in that area would almost have to come from the head gasket unless the o-ring on the coolant pipe was leaking but I would think that would if it were an issue with the o-ring you would see it spraying out once the system held pressure.

You could put some dye in the coolant and then try to trace the source of the leak with a black light.

I didn’t give the machinist specific instructions for an MLS gasket I honestly didn’t know there was a difference in the process

 

[danl]

Does arp say 105 ft pounds for the L19’s? I had issues with HG leaks when I would over torque the studs, trying to keep the head down. I believe the head was applying uneven pressure, causing the leak.

Cameras are cheap, put a GoPro in there to monitor the situation if you are going to do another pull.

If you can, install a pressure sensor to monitor coolant pressure.

You can also pressurize the cooling system with a tool and check for leaks. If you have a borescope check inside the cylinders for a drop of coolant at the hg junction. It takes a lot of patience to identify a leak this way.

 

[all black 4G63]

Does arp say 105 ft pounds for the L19’s? I had issues with HG leaks when I would over torque the studs, trying to keep the head down. I believe the head was applying uneven pressure, causing the leak.

Cameras are cheap, put a GoPro in there to monitor the situation if you are going to do another pull.

If you can, install a pressure sensor to monitor coolant pressure.

You can also pressurize the cooling system with a tool and check for leaks. If you have a borescope check inside the cylinders for a drop of coolant at the hg junction. It takes a lot of patience to identify a leak this way.

Thanks for the insight

 

[Dericsh]

You can also pressurize the cooling system with a tool and check for leaks. If you have a borescope check inside the cylinders for a drop of coolant at the hg junction. It takes a lot of patience to identify a leak this way.

I prefer to do this test in reverse. Pressurize the cylinder with a leak down tester, and look for bubbles in the coolant.

 

[all black 4G63]

I pressurized my cooling system to about 20psi and nothing. I did leak down and nothing. This sucks

 

[TerminalTalon]

That’s a rough one if it holds pressure at 20psi. How long are you pressurizing it for and you need to have a spray bottle with dish soap ready to make sure, specifically the waterpump side because the blocks and the gaskets are a pain to seal correctly. I pressurized a Evo I did a timing job on and the gasket, put on perfectly dry with a “perfect surface” didn’t hold. I went thru 3 gaskets. Just an example.

 

[all black 4G63]

Does anyone know if 26-29 lb boost is too much for 93 octane?

 

[TerminalTalon]

If you keep the timing low. We’ve seen 30+ psi on 93 cars years ago.

 

[all black 4G63]

If you keep the timing low. We’ve seen 30+ psi on 93 cars years ago.

Yeah thanks I’m starting to think that my coolant issue is just that I’m pushing it too far on 93 and lifting the head.
So if I see this coolant does this mean my head gasket is already smoked? However, I have no other coolant issues or drivability related problems

 

[Vegas Smith]

I would add a coolant pressure sensor and see if pressure spikes during a pull. It will go up a little due to the water pump blades churning faster but you can search around a bit and find info on what amount of pressure rise is too much. I think I found info on the Link ecu forums about that.

 

[all black 4G63]

I would add a coolant pressure sensor and see if pressure spikes during a pull. It will go up a little due to the water pump blades churning faster but you can search around a bit and find info on what amount of pressure rise is too much. I think I found info on the Link ecu forums about that.

Thanks but is it recommended to install the sensor on the block side below the t-stat or above it on the housing upper radiator side?

 

[Vegas Smith]

Thanks but is it recommended to install the sensor on the block side below the t-stat or above it on the housing upper radiator side?

I don't know what the correct location is, but I can tell you I have mine in my lower tstat housing---not sure what location is "correct" though.

 

[all black 4G63]

I don't know what the correct location is, but I can tell you I have mine in my lower tstat housing---not sure what location is "correct" though.

What kind of readings/pressure are you seeing? Does the pressure rise significantly when accelerating due to water pump speed increase?

 

[TerminalTalon]

I’d pull the pipe first and check the oring. Pressure test for hours. If it drops there is a leak somewhere. If you were pushing the headgasket there would be other signs I’d hope.

Also make sure the pipe is centered in the water pump. Different pressures on the system do different things to seals.

 

[all black 4G63]

I’d pull the pipe first and check the oring. Pressure test for hours. If it drops there is a leak somewhere. If you were pushing the headgasket there would be other signs I’d hope.

Also make sure the pipe is centered in the water pump. Different pressures on the system do different things to seals.

Good idea thanks