What color would it be inside if I burn coolant? I am running e85 and spark plugs are white.

 

There was no visible damage when I pulled the head off to change head gasket. They look good and they sticking out evenly above the block. I did measured them and they are around 3-4 thousands out. I will continue to drive it and watch the coolant.

 

right. it should be DRY thin light brown. if youre burning fluids then its going to be damp in there, possible a trail made by condensation

 

I will look at it. I noticed when I pulled the head out there was a lot black gunk on top of the pistons but that might be from e85.

 

i think thats oil if you have a working pcv system

 

Hey guys problem with coolant loosing is still not fixed. I pulled the cylinder head again and changed the head gasket again this time I sprayed gasket with cooper spray.I measured the block for flatness and look pretty straight( I know machine shop can only measure it the right way but I measured blocks before with good results) I am building second engine so I will install it when its ready but I am still fighting with current motor and coolant disappearing. I have never ever seen anything like this before and I am working on cars every day. Car is taking coolant somewhere but I dont know where. It is not leaking I was pressurizing the coolant system and it does hold pressure and is not leaking anywhere. Oil doesn't look like there is a coolant in it its not milky or anything like this. I am using valveline 20-50 oil and its color is green/blue color so its hard to say but for sure its not milky and doesn't look like there is coolant in oil. Am I burning coolant?? All 4 spark plugs looks the same, I think I would notice it if it would burn coolant but smell behind the car is sweet because of e85 so I dont know anymore. Since May 2022 I added around half gallon of coolant so obviously there is a problem. It is loosing same amount of coolant either I am boosting or not. It is starting to **** me off because I can't find it. I will install second engine in a couple of month but before I pull this one out I would like to find out the problem, this way I would know if I can reuse block or head in the future. Thanks guys!!!

 

Hey boss, iam having a similair issue also. built evo 8 ,O-ringed head also. did you ever figure it out?

 

Yes I found the problem. In my case I had cracks on the top of the block coming from coolant ports to the head studs. To my surprise it is pretty common on high hp evo with high torqued head studs.Block is flexing on high power/boost and high torqued heads studs are trying to prevent flexing and block is cracking. How much power are you making and what head studs are you using with how much torque?

 

hey bud,srry took soo long to get back to u. Iam making 830hp and 642 trq. Iam also using 625 headstuds. Recently took off my head and have found cracks from the headstud holes that are nearest to the coolent passage holes also. Have u found a way to stop this from happening? And did u move ur parts from the cracked block to a good known core?

 

Hey, I am currently testing new engine that I build couple months ago. This time I half filled the block with concrete and I strongly believe that with 1/2 concrete fill engine will flex less than with no concrete in it. I talked to many people that making crazy power on evo blocks and almost all of them said that cracks are pretty common if your power is high and if you are using arp 625 studs. It is less common for block to crack on regular arp head studs and lower clamping torque on them but it is more common to blow head gasket than. Regular arp studs will let the block flex and lift the head under boost. On my current engine I did 1/2 fill like I mentioned above as well as 625 studs torqued to 95lbs. Old engine I will disassemble completely and reuse all internals but I will change the block. I also talked to Terry from machine shop called Class One in freeport IL he just recently retired but he was in the 4g63 world for the last 30+ years and he told me that he did seen brand new 4g63 blocks torqued to 100lbs and pushed over 800+whp that cracked block in those common places withing days of driving/boosting. The coolant is disappearing slowly and it is hard to find but coolant is going to the oil in most cases with those cracks. It is so little that you have a hard time to catch that especially when you change oil every 1500 miles like me. I sent oil to the testing and sure enough they called me and said that there is coolant in the oil but oil was never milky or did not change color. Hope I helped with what I know. I will let you know in couple of months how my 1/2 filled block is holding.

 

So the final diagnosis is cracks in the block at the 625 studs leaking coolant into oil. I would suggest that oil analysis be one of the first things done if anyone have this issue. I use Blackstone labs but really any reputable analysis lab would work. The cost is $ and would have directed the efforts better
OT but the head has oil passages close to coolant passages too. Might be work investing in pulling the head and having it dye checked inside and out for cracks. :-)

 

if you look at oil testing kits on Amazon, you can see the (bad) reviews

 

yeah, honestly the only reason i was able know that i was having some kind of coolent issue was because ,i have a coolent pressure sensor hooked up my haltech 1500. My coolent temps never go above 190-200°f on a very hot day.
The wierd thing is my coolent pressure would rise to about 26psi when the car is idling. My radiator cap is rated for 21psi of pressure. I have the csf slim full size rad.if it werent for my coolent pressure sensor i would of have no way to even know i was having coolent issues. It gets even weirder when i go WOT the coolent pressure will come back down to around 6psi -10psi give or take. Then when the car is idling it will shoot back up to 26psi or so.whats more funny is that i dont shoot coolent to the resivour even when the sensor reads over 21psi. But i know theres alot of pressure because my top and bottom hose are really stiff. And if i bleed the motor with the bleeder funnel and let the funnel sit with coolent over night,the nxt day i notice that the coolent left over on the bleeder funnel would have less then before. Mind you the bleeder funnel still hooked up to the radiator.So my coolent has to be going somewhere where there is cracks. Like you mention also iam running HPL 20w-50 oil and iv check my oil no signs of coolent mixture.
On your 1/2 fill block with 95ft lbs ,is it working for you? Has the head lifted yet?

 

On my current 1/2 fill block I am on break in period for the first 200-300 miles so I did not apply any boost yet. After the break in period I will turn boost where it was on old motor 44-45psi and see the results. I will post whenever I know anything. Send you oil to the blackstone laboratories they are in Indiana. They will check if there is any signs of coolant in oil. They called me and told me there is coolant in you engine please immediately stop driving it. Just because it is my personal car I was changing oil more often and I was driving like that for the another 6-7 months for testing purposes hahah.

 

I had a weird issue a few years back in one of my Evo 8’s. I would literally loose all coolant, tank was bone try. I replaced my radiator cap and it fixed it. May not be your issue but worked for me.