By pass all the extra's and pull the screen sounds like a good plan.
Builds Isuzu 4BD1T Lexus LX450 (Land Cruiser) Build (2 Viewers)
- Thread starter Wheelingnoob
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Have you re torqued the head by chance? Might be a good idea as well just Incase things loosened off as you've cycled it quite a few times now.
- Thread starter
- #823
Yeah I should try that as well before I pull the head.
Going to try removing all my "add on's" first then re torque.
Im not sure how it would have blow the head gasket since its metal and I have only fed it 20psi max boost. EGT's have been kept under 1100f except one 1200f tap for about 2 sec.
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Going to try removing all my "add on's" first then re torque.
Im not sure how it would have blow the head gasket since its metal and I have only fed it 20psi max boost. EGT's have been kept under 1100f except one 1200f tap for about 2 sec.
...via IH8MUD app
I don't think you've "blown" the HG, but rather it's just not sealed. Pretty common for MLS gaskets as far as I've read since there so inflexible. Feel like increasing the bolt torque? If you redo the HG I can't really think of what yould do differently. More copper spray? Like more than your comfortable with?
did you go the ARP route for the head studs?
I would think a higher clamping pressure may be beneficial especially with the MSL gasket.
I would think a higher clamping pressure may be beneficial especially with the MSL gasket.
I am completely out of my depth on this model LC and the engine, but from my own silly mistakes in the past. Have you perhaps bypassed on of the heaters by using a hose instead of blocking them off? ( Don't ask how I know of this).
reversing you own mods and checking the screen would also be good. With all the work you have put in I really feel for you, but remain convinced that it's something simple.
reversing you own mods and checking the screen would also be good. With all the work you have put in I really feel for you, but remain convinced that it's something simple.
Things that you may or may not have tried, tested or checked - 1. radiator inlet & outlet soldered in the correct position to spread /collect coolant in radiator tanks or flow will be down the few tubes nearest (seen this done more than a few times by radiator shops), the inlet/outlet have cutouts, 2. foreign object (rag/plastic)left in hoses /radiator causing reduced circulation (can also be ingested by water pump), 3. test water pump output pressure by attaching a hose to engine side of thermostat and with cold engine slowly run up to 3000 rpm while lifting open end of hose in air taped to broomstick - it should easily lift 10 to 12 feet @ 3000 -make sure your cap is off, coolant full & engine cold ( it's easier with 2 people), 4. does your heater inside your car work properly?, 5. Isuzu thermostat should start to open @ 82 (180) deg & fully open 94 (202) deg , make sure it opens fully, they will fit upside down, 6. a good fan thermo clutch will not engage if there is no heat from radiator flowing over the control strip on the front of the clutch, 7. if you want to stop flow to coolant filter/block heater etc use some vicegrip pliers & fit hose to jaws, or use something similar to brake line locks, then you can clamp off hoses to stop flow, flow problem should show up in 3 above, 8. if you think you have a head gasket problem a test kit for exhaust gas in coolant could be useful, you could also do a very quick torque converter stall test with a COLD engine & hose hooked to highest point ( where you have your funnel for bleeding) and the other end into a bucket of water, if you get lots of bubbles instantly when power is applied you have a compression leak somewhere, 9. coolant can foam in the water pump and reduce circulation in some conditions, just try plain water in the engine to test this, 10. the head gasket will fit front to back, check the tab with the notch is at the back of the head. Sorry for being so long winded. Hope this helps.
Hooking the pressure gauge up and running it should show you any combustion pressure build up in the cooling system
Fabmec brought up a really good point, the thermostat upside has burned me in the past in the same way you're having problems. Also I will ask... who did you buy the thermostat from...?
Well fabmec that's the biggest first post I've seen in a while.... Hello. All these ideas are great I must say but Jeremes already got the smoking gun. He noticed a 1mm section of his head gasket blowing out hot gasses? That's not anything other than an unsealed gasket and it should be sealed quickly or it will jet the nitrile off of it and it will never seal.
I just double checked my spare 4BD2 and an old HG, and the HG can not be reversed. The head bolt holes do not line up.
As Gerg said, you haven't blown the head-gasket. Rather something is stopping it from sealing. There is little elasticity in MLS gaskets and each surface has to be pretty much perfect. I use a large flat oil stone to surface each face (head and deck) before fitting the gasket and have no problems. I don't use any sealants or sprays as they can build up pressure and prevent the critical surfaces from sealing as the should.
Once you have a leak through, you won't get a reseal by retorquing. You need to pull the head and clean all surfaces. It will be obvious where it has leaked when you get it apart.
Not necessary. These hold 60psi boost with factory gasket and factory bolts if all is good.
Holding onto a hose will show it building pressure. A gasket leaking under combustion pressure won't vent at idle. You need to load the engine and build boost.
Good question on the thermostat. But it won't introduce air or pressure.
I stand corrected on if the HG can be reversed!
When I checked it earlier, I placed the HG on top of the head, I just removed the head and placed it the block. It can be flipped!
I think the old HG I have is an Isuzu OEM, it has a stamp - Top Front - on the front corner above the IP. It also has a tab that overhangs the block deck. The tab overhangs the rear on the oil filter side and is about 1.5" wide and is proud to the rear about .25".
If the HG is flipped, it blocks a couple of passages completely, and a couple part way. I would check for the tab!
Here are a couple of pictures for future reference. You can see the tab, the note and some of the blocked cooling passages.
When I checked it earlier, I placed the HG on top of the head, I just removed the head and placed it the block. It can be flipped!
I think the old HG I have is an Isuzu OEM, it has a stamp - Top Front - on the front corner above the IP. It also has a tab that overhangs the block deck. The tab overhangs the rear on the oil filter side and is about 1.5" wide and is proud to the rear about .25".
If the HG is flipped, it blocks a couple of passages completely, and a couple part way. I would check for the tab!
Here are a couple of pictures for future reference. You can see the tab, the note and some of the blocked cooling passages.
- Thread starter
- #833
I do not think I got the gasket in backwards, I remember double checking it.
Ill check for the tab though.
I will also get a picture of the area that i think maybe leaking.
How do you oil stone the block with the sleeves in? They stick up a bit. My block surface was far from perfect if you read back so maybe that is the issue.
I hate the idea of pulling the head but it maybe my only option. Im going to clamp off the couple lines I have run non factory and try and get a good bleed done on it tonight.
Hell if a way to break in a fresh motor
Hope it did not score any sleeves.
...via IH8MUD app
Ill check for the tab though.
I will also get a picture of the area that i think maybe leaking.
How do you oil stone the block with the sleeves in? They stick up a bit. My block surface was far from perfect if you read back so maybe that is the issue.
I hate the idea of pulling the head but it maybe my only option. Im going to clamp off the couple lines I have run non factory and try and get a good bleed done on it tonight.
Hell if a way to break in a fresh motor
Hope it did not score any sleeves. ...via IH8MUD app
I think I went around the sleeves on the block deck. The head surface was the main one that required the stoning.
- Thread starter
- #835
Thanks Dougal, ill try and find a large oil stone.
So tonight I took off the thermostat cover and removed the thermostat to test it. It was in the correct way and started to opening at 180f and was fully open at about 200f. Its OEM Isuzu thermostat that was new when I put it in.
I then spent the next 2 hours bleeding it and making sure all the air was out of the system. Im 99% sure all the air is out.
I then went for a test drive my same route same speed......same result. Got hot 1 exit down cranked the heater and was barely able to keep the temp under control.
So yeah I guess tomorrow I order a head gasket.
...via IH8MUD app
So tonight I took off the thermostat cover and removed the thermostat to test it. It was in the correct way and started to opening at 180f and was fully open at about 200f. Its OEM Isuzu thermostat that was new when I put it in.
I then spent the next 2 hours bleeding it and making sure all the air was out of the system. Im 99% sure all the air is out.
I then went for a test drive my same route same speed......same result. Got hot 1 exit down cranked the heater and was barely able to keep the temp under control.
So yeah I guess tomorrow I order a head gasket.
...via IH8MUD app
whats arp studs worth for this engine?
Don't they get torqued to like double what factory is?
I am 100% sure this would seal up the MLS gasket.
Don't they get torqued to like double what factory is?
I am 100% sure this would seal up the MLS gasket.
- Thread starter
- #837
I do not even know if they have them for this engine.
With the metal head gasket they are very intolerant of imperfections in the sealing surface. I have used them in the past no amount of torque in the head bolts/studs will seal them.
While I have the head off its going to reputable shop to make sure its not cracked now.
I hope to get this turned around as fast as I can. My biggest fear is its not going to fix the issue. Strange that tonight I had almost no air come out of the bleeder after its run. Im going to let it cool over night and see how much I can add.
If its not a head gasket/head what else would cause this? I can drive it around hours on city streets with out the temp gauge moving. Hit the hwy and its heats up within 5min.
Bummed.
...via IH8MUD app
With the metal head gasket they are very intolerant of imperfections in the sealing surface. I have used them in the past no amount of torque in the head bolts/studs will seal them.
While I have the head off its going to reputable shop to make sure its not cracked now.
I hope to get this turned around as fast as I can. My biggest fear is its not going to fix the issue. Strange that tonight I had almost no air come out of the bleeder after its run. Im going to let it cool over night and see how much I can add.
If its not a head gasket/head what else would cause this? I can drive it around hours on city streets with out the temp gauge moving. Hit the hwy and its heats up within 5min.
Bummed.
...via IH8MUD app
Sounds like it really need some good pressure to leak. That's good news I'd say. I feel for ya as I've dealt with the same stuff in the past. Take a break and have some ice cream. Everything looks better in the morning.
Cheers
Cheers
- Thread starter
- #839
Had another though, timing. I know my pump timing is set at 13deg. But what if the injector pop pressure was too low? Would they then open too early causing the timing to retarded? I ask because amongst all the overheat/ oil pressure worries there has been a less important one that maybe the cause.
Boost is sluggish 8psi 2000rpm 20psi at 3000rpm. I have the fuel screw turned out only one turn and EGT's are only controllable by my foot. I can easily and very quickly hit 1200f running 18ish psi on the hwy (talking 2-3sec). I have no visible smoke out the tail pipe if anything its a very very slight haze. The hot side of the intercooler is well hot and the cold side is cool to the touch after a run so I know its working.
I just do not know if this would also cause the hot hwy temps? Cruising I'm anywhere from 850-1000f at 100km/hr if I hit a hill it will again sky's the limit unless I back off.
The turbo is just not preforming how I thought it should, the big thing is the slow response and low peak boost of 20psi (25psi W/G spring and 1/4" preload). I do not hit 20psi unless under lots of load foot too the floor and 2700+rpm. Again EGT's only controlled by my foot. As it sits now there is no way this turbo will use up all the fuel this pump can deliver.
Thoughts?
I may pull the injectors tomorrow and have them pop tested to see.
...via IH8MUD app
Boost is sluggish 8psi 2000rpm 20psi at 3000rpm. I have the fuel screw turned out only one turn and EGT's are only controllable by my foot. I can easily and very quickly hit 1200f running 18ish psi on the hwy (talking 2-3sec). I have no visible smoke out the tail pipe if anything its a very very slight haze. The hot side of the intercooler is well hot and the cold side is cool to the touch after a run so I know its working.
I just do not know if this would also cause the hot hwy temps? Cruising I'm anywhere from 850-1000f at 100km/hr if I hit a hill it will again sky's the limit unless I back off.
The turbo is just not preforming how I thought it should, the big thing is the slow response and low peak boost of 20psi (25psi W/G spring and 1/4" preload). I do not hit 20psi unless under lots of load foot too the floor and 2700+rpm. Again EGT's only controlled by my foot. As it sits now there is no way this turbo will use up all the fuel this pump can deliver.
Thoughts?
I may pull the injectors tomorrow and have them pop tested to see.
...via IH8MUD app
