Coolant in cylinder after rebuild

[Merenth]

I'm sure I'm going to get slammed for asking a so called "stupid" question, but here it is anyways. I have a freshly rebuilt block mated to a freshly rebuilt head. These were rebuild separately and assembled by me. Used an OEM replacement HG combined with the copper spray seal to fill any surface irregularities. After putting everything back together and starting the engine, there is a small amount of coolant that is leaking into all 4 cylinders that eventually bogs down the engine. Additionally, there appears to be exhaust gases leaking into the coolant.

I pulled the head off, and checked the block and head mating surfaces for galls, scratches, marks, etc., as well as checking for a true surface. No damage to either the head or block visible, plus appears to be a good seal on the HG based on the fact that there were no traces of fluids in between the cylinders and either oil or coolant passages. There was obvious compression of the gasket as well demonstrating the seal. No fluids in the intake so it shouldn't be from a destroyed turbo either.

I then reinstalled everything with a new HG and tried again, ending with the same result. I can only think of two things that could cause this that supposedly should have been solved by getting rebuilt parts (not from ebay before anyone asks). Either a crack in the head which should have been detected by a pressure check or a minute crack in the block which should have been detected by magnaflux. I would point out on this one that it would have to be very small as there are no visible signs like carbon buildup in a crack.

Can anyone think of anything else to check or other problems I haven't addressed?

 

[Slowboy]

I'm sure I'm going to get slammed for asking a so called "stupid" question, but here it is anyways. I have a freshly rebuilt block mated to a freshly rebuilt head. These were rebuild separately and assembled by me. Used an OEM replacement HG combined with the copper spray seal to fill any surface irregularities. After putting everything back together and starting the engine, there is a small amount of coolant that is leaking into all 4 cylinders that eventually bogs down the engine. Additionally, there appears to be exhaust gases leaking into the coolant.

I pulled the head off, and checked the block and head mating surfaces for galls, scratches, marks, etc., as well as checking for a true surface. No damage to either the head or block visible, plus appears to be a good seal on the HG based on the fact that there were no traces of fluids in between the cylinders and either oil or coolant passages. There was obvious compression of the gasket as well demonstrating the seal. No fluids in the intake so it shouldn't be from a destroyed turbo either.

I then reinstalled everything with a new HG and tried again, ending with the same result. I can only think of two things that could cause this that supposedly should have been solved by getting rebuilt parts (not from ebay before anyone asks). Either a crack in the head which should have been detected by a pressure check or a minute crack in the block which should have been detected by magnaflux. I would point out on this one that it would have to be very small as there are no visible signs like carbon buildup in a crack.

Can anyone think of anything else to check or other problems I haven't addressed?

#1) Was the head decked/ resurfaced?

#2) Was the block decked/ resurfaced?

95% of the time - #1 or #2 was not done, or not done properly (IE - the surface finish was not adequate).

Mike Huml

 

[Merenth]

Yes, they were both decked. Whether or not they were decked properly is another matter. They are both at least true, checked at multiple angles for any warping and didn't come up with anything. They were not polished to mirror shine, but both are obviously milled.

 

[GsXdSmKingGsX]

No such thing as a stupid question in my eyes. Your stupid if you DONT ask questions you dont know.

 

[Slowboy]

Yes, they were both decked. Whether or not they were decked properly is another matter. They are both at least true, checked at multiple angles for any warping and didn't come up with anything. They were not polished to mirror shine, but both are obviously milled.

Any pictures of the surface finish by chance?

They do not have to have a "mirror" shine - but should be under 30-35 RA to seal properly.

Two guess's are that or small crack in the cylinder head (although very rare on the 4G63's from what we have seen - EJ cylinder heads are a different story!)

Mike Huml

 

[GsXdSmKingGsX]

Suggestion. Send it to Slowboy to get it done right!

 

[Merenth]

Unfortunately I don't have pictures because I'm not with the car right now. I had to think long and hard on this one to consider options before giving up and just asking. Essentially it's a fairly polished surface with the standard faint arcs from the milling machine on the surface. There is not enough surface variation to catch a fingernail or anything.

 

[Slowboy]

Unfortunately I don't have pictures because I'm not with the car right now. I had to think long and hard on this one to consider options before giving up and just asking. Essentially it's a fairly polished surface with the standard faint arcs from the milling machine on the surface. There is not enough surface variation to catch a fingernail or anything.

Have you tried a leak down test?

I think this is your next logical step if the car is together right now.

Mike Huml

 

[redyute1]

Boy i got the exact same problem.Jumped timing bent one intake valve,went to the pick and pull got a head for $55.00,sent it to shop had it resurfaces ,i changed the valve seals got an oem head gasket then re installed it.Fired it up msfire #3 cylinder, pulled the plug out and steam blows out and it shits white smoke.So i figured the head may be cracked,got another one this time got the works,pressure test,resurface slap it back on and boom same shit antifreeze in #3 cylinder.I sat down and thought about it, maybe my block is cracked,but she ran fine before and she never over heated.So i said to hell with it and decided to start a new build capable of 600 hp,thats where i am at right now coming slowly but surely.The only thing i can say in my situation is my arp head studs probably got stretched from reusing them, thats the only explaination i have in my case that is

 

[BogusSVO]

the surface finish of both the head and block should be about like this..
http://www.dsmtuners.com/forums/new...face-4g63t-cylinder-head-mls-head-gasket.html

if the surface finsh looks like this.. it is not proper...
http://www.dsmtuners.com/forums/cyl...0613-why-not-let-your-head-belt-surfaced.html

you said your getting coolent into all 4 cylinders, but nothing in the intake...

was the block bored? if so how much? did you go .060, this would be rare, but if you have a block with bad core shift, and thin walls the coolent could weep thu the walls and into the cylinders, THIS is very rare but can happen....

I am not sure about this.. but do the TB have a water passage thu them for cold starts/pre heating? then you may have a rot spot in the TB that is sucking coolent into the cylinders.

 

[Merenth]

Have you tried a leak down test?

I think this is your next logical step if the car is together right now.

Mike Huml

Is there any convenient way of doing this? Pretty much everything I've heard is that you need to take it to a dealership for this to be done. Compression test shows within spec anyways, but this may be influenced by the fluid in the cylinders I suppose.

To answer BogusSVO, yes, the block was bored to .020" over, so there shouldn't be an issue with weeping, especially not in the amount I've seen. And yes, there is a water passage in the TB, but with no fluid on the intake, I doubt that this has anything to do with it.

Any other ideas?

 

[Slowboy]

Is there any convenient way of doing this? Pretty much everything I've heard is that you need to take it to a dealership for this to be done. Compression test shows within spec anyways, but this may be influenced by the fluid in the cylinders I suppose.

To answer BogusSVO, yes, the block was bored to .020" over, so there shouldn't be an issue with weeping, especially not in the amount I've seen. And yes, there is a water passage in the TB, but with no fluid on the intake, I doubt that this has anything to do with it.

Any other ideas?

Most DSM shops (or EVO shops) will charge you an hour of labor to do a leak down test and look over the car - in our case its $85.00 plus tax at our shop. Compression test is not going to show what we are looking for.

Sorry you are far away,

Mike Huml

 

[Black95TSIawd]

I would bring the head to a machine shop to get check one more time. That isn't too expensive either.

 

[Merenth]

Most DSM shops (or EVO shops) will charge you an hour of labor to do a leak down test and look over the car - in our case its $85.00 plus tax at our shop. Compression test is not going to show what we are looking for.

Sorry you are far away,

Mike Huml

Well, on this note, anyone have a recommendation of a good DSM shop in either the Dallas, TX area?

And after this I will certainly do my best to get the head tested first, then the block, and if all else fails start replacing them.

 

[BogusSVO]

do a coolet pressure test.. and look for the water to come out....it is a simple test to do... you may be able to "rent" it from the parts store....

pull your air intake pipe, and your spark plugs... hook the pressure tester in place of the rad cap.. pump the coolent system up.. and see if you can find where the water is being pushed out

 

[DSMDEMON93]

Any head "pitting" accounted for?