Head gasket question

['94IDITurbo7.3]

there are two ways that a head gasket can leak, internal or external, internal would mean you would need to do a block test. block test finds hydrocarbons in the coolant. here is a block tester from napa.
http://napaonline.com/Catalog/CatalogItemDetail.aspx?R=BK_7001006_0361073538
external would mean you would need to get engine to operating temp and then pressure test it, OR, you add dye to the coolant and then run the engine for a while and look for the dye. here is the type of dye im refering to from napa.
http://napaonline.com/Catalog/CatalogItemDetail.aspx?R=NTE784702_0282517235
either way, good luck.

thanks for the links. based on my pics and the fact that i have ZERO evidence of coolant in the exhaust i think i would have the external gasket failure.

In order for pressurizing the radiator to show, I'd bet you'd need the thermostat to be open. Maybe not though, I'd definitely try it.

that does make sense.

 

['94IDITurbo7.3]

And if you are changing the HGs, why not invest a few bucks in studs? New bolts (yes, you really need to use them) cost nearly as much.

yeah that is what i need to decide on.

i can see how money would/will add up FAST. i put in studs, then i don't have to worry about heads coming up again, hey then i could throw an IC on there and really take advantage of this turbo. hmmm

 

[89greendiesel]

thanks for the links. based on my pics and the fact that i have ZERO evidence of coolant in the exhaust i think i would have the external gasket failure.


that does make sense.

what else are you planning on doing to the truck maintenance/performance wise? Might help determine whether or not you want to keep it.

 

[justinray]

it wouldnt matter if the thermostat is open due to there being an inlet and outlet to the radiator. pressure will be on both sides of the thermostat if its closed, as well as if it was open.

I understand wht you are trying to say here, but pressure is only a measure of resistance, in order for pressure to be near the same at the headgasket area, you need to minimize the resistance elsewhere.

 

['94IDITurbo7.3]

what else are you planning on doing to the truck maintenance/performance wise? Might help determine whether or not you want to keep it.

if i stick with stock head bolts then nothing, if i go with studs then it would just be probly IC and increase boost. i would much rather go for performance with a new diesel.

 

[justinray]

IDI headbolts are not tty.

 

[The Warden]

IDI headbolts are not tty.

They're not torque-to-yield, but it's still generally recommended to replace them...and IMHO studs are a worthwhile upgrade to ANY turbo'ed engine.

 

[wmoguy]

if i stick with stock head bolts then nothing, if i go with studs then it would just be probly IC and increase boost. i would much rather go for performance with a new diesel.

Eric I'll kick ya in the nuts if you do head studs (pulling the block) and you don't do a cam at the same time.


j/k I wont literally do that.




IMHO, your in college, your young, and your money right now should go towards your education. Ditch the headstuds, get it done and cheaply, but as reliable as possible. Yes reliable can be done w/o studs, just be cognizant of what you can and can't do without them. When your out of school, have a good paying job and can pay cash for either a newer pickup you can hotrod, or have the cash to hotrod this one, then do it. Until then, get decent reliable transportation, and be glad with what you have.

 

['94IDITurbo7.3]

Eric I'll kick ya in the nuts if you do head studs (pulling the block) and you don't do a cam at the same time.


j/k I wont literally do that.






IMHO, your in college, your young, and your money right now should go towards your education. Ditch the headstuds, get it done and cheaply, but as reliable as possible. Yes reliable can be done w/o studs, just be cognizant of what you can and can't do without them. When your out of school, have a good paying job and can pay cash for either a newer pickup you can hotrod, or have the cash to hotrod this one, then do it. Until then, get decent reliable transportation, and be glad with what you have.

yeah i hear you on the school thing. it depends on how much i can get studs for.

 

['94IDITurbo7.3]

ahhhhhhhhhhhhhhhh, the images of my boost gauge being north of 10-12 psi in my head is very tempting.

 

[IDIBRONCO]

When I worked for a shop that remanufactured these engines, we always reused head bolts with no comebacks. I'd agree with the studs for more boost. The cost could easily be justified by thinking of what it would cost to have a head gasket blow out and then have to do it all over again! Another reason would be that it's a lot easier to remove a head when it's out, which it will be anyway to install the studs.

 

[trackspeeder]

ahhhhhhhhhhhhhhhh, the images of my boost gauge being north of 10-12 psi in my head is very tempting.

Go for it.

 

[MUDKICKR]

I understand wht you are trying to say here, but pressure is only a measure of resistance, in order for pressure to be near the same at the headgasket area, you need to minimize the resistance elsewhere.

but you do understand that when doing a pressure test, the cooling system is full of coolant, and your only adding enough pressure to push on the antifreeze. the pressure is still going to be the same to the headgaskets cause the radiator will push coolant from the bottom of the radiator into the engine. the only reason to do it hot is if the leak is only there when engine is hot. also, the way the cooling system works is the water pump pulls coolant from the lower radiator hose into the engine, then pumps it throughout the engine, and the thermostat stops the coolant flow to let the coolant pull heat from engine/heads for heater core, after the thermostat opens it lets the coolant go into the radiator by the upper radiator hose and recirculate. honestly the real reason there are thermostats in vehicle engines is so we can have a heater, they are not really needed other then that.
if the cooling system had a place that stopped flow, then i could see it being an issue, but since the cooling system as a whole recirculates, with only one inlet, then there is no pressure difference if the thermostat is open or closed.

 

[justinray]

but you do understand that when doing a pressure test, the cooling system is full of coolant, and your only adding enough pressure to push on the antifreeze. the pressure is still going to be the same to the headgaskets cause the radiator will push coolant from the bottom of the radiator into the engine. the only reason to do it hot is if the leak is only there when engine is hot. also, the way the cooling system works is the water pump pulls coolant from the lower radiator hose into the engine, then pumps it throughout the engine, and the thermostat stops the coolant flow to let the coolant pull heat from engine/heads for heater core, after the thermostat opens it lets the coolant go into the radiator by the upper radiator hose and recirculate. honestly the real reason there are thermostats in vehicle engines is so we can have a heater, they are not really needed other then that.
if the cooling system had a place that stopped flow, then i could see it being an issue, but since the cooling system as a whole recirculates, with only one inlet, then there is no pressure difference if the thermostat is open or closed.

Without the thermostat, you lose much more than the heater. With our engines, I'd bet you would lose the engine or heads before too long.

 

[MUDKICKR]

Without the thermostat, you lose much more than the heater. With our engines, I'd bet you would lose the engine or heads before too long.

interesting, i would be interested in this theory