I have the original d16a6 in my si hatch. I'm rebuilding another a6 motor for it slowly for boost but just my luck the headgasket blew last week and my new motor is no where near ready. The reason my headgasket blew is because of an overheat, due to a small crack that developed in my radiator and drained the system quickly. The car did overheat but did not touch the red on the gauge, just got close to it.

I'm trying to decide if I can just replace the headgasket and drive it around for now until I finish my build.

I know the car has had the headgasket replaced about 30k miles ago with another oem equivalent (non-MLS). The guy who changed it (previous owner) said he had the head milled enough to make it straight and nothing more.

He also said the deck was at .004" which is near the max service limit but not over it so they left it alone.

According to the helms the deck limit is .004" and the head is .002".

Is the straightness of the deck extremely important in non boost apps? I'm hoping I can just pull the head have it straightened again and throw it back on without worrying about the block.

Should I worry about the deck much?

Any recommendations on what headgasket to use? I've read that the oem a6 gasket is a POS. If anything I would like to use the Y8 MLS 3 layer gasket, and then coat it with copper spray to help out. Is the composite a6 gasket more lenient when it comes to deck warpage than the 3 layer MLS?

If its of any importance, the way it's leaking right now is just by burning coolant slowly. Enough to smell and drain the cooling system every few days (50 miles or so), but not enough to see the white smoke and not enough to cause overheating. It is enough to make the 02 recognize it and throw a code, and enough to cause hesitation once fully warm (probably flooding out spark in one of the cylinders).

Thanks

 

Is it only leaking internally? Is there coolant in your oil? If not then i would say you could get away with just replacing the head gasket with a MLS. For peace of mind i would get them both milled, but thats just me. Also if you are building something else on the side, i would just replace the head gasket. It will be fine.

 

thats correct, no coolant in the oil. I've got a spare block I'm working on but it is in non running condition at the moment and I need something to get around until I finish building it. I don't want to short change my new build by being forced to finish it quickly. I was taking my time to build it with OEM parts and ARP studs etc..


I would love to get the deck milled as well as the head, but don't have the time to pull the motor out and take it down to the shop




Modified by bambbrose at 7:12 PM 9/20/2007

 

no other input?

 

On the block there are dots to have a minimum resurfacing mark level.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1988hondacrxsiR1 &raquo;</TD></TR><TR><TD CLASS="quote">On the block there are dots to have a minimum resurfacing mark level. </TD></TR></TABLE>

ok... what does that have to do with the issue at hand??


again, I do not want to pull my block apart to deck it. I'm just asking for opinions on how important the deck straightness is to sealing.

If anybody has experience, please post up.

If you never even measured your deck, post up. I'm curious if most people just don't even worry about it

 

The deck must be resurface for a nice clean seal for the headgasket. If not expect coolant and oil mix in the long run.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1988hondacrxsiR1 &raquo;</TD></TR><TR><TD CLASS="quote">The deck must be resurface for a nice clean seal for the headgasket. If not expect coolant and oil mix in the long run.</TD></TR></TABLE>

so you are telling me that all of the shops and people across america who just change their headgasket should expect their coolant and oil to mix?

How many headgaskets have you changed?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bambbrose &raquo;</TD></TR><TR><TD CLASS="quote">

again, I do not want to pull my block apart to deck it. I'm just asking for opinions on how important the deck straightness is to sealing.

If anybody has experience, please post up.

If you never even measured your deck, post up. I'm curious if most people just don't even worry about it </TD></TR></TABLE>

I don't think that there is a service limit for straightness. Unless the block or head got warped from overheating, and that's how you blew the gasket, then I wouldn't worry.

If the gasket just went cause it's old, then fine. If it went for a reason, then it's probably due to warping from overheating and I would have it re-surfaced.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tippyman &raquo;</TD></TR><TR><TD CLASS="quote">

I don't think that there is a service limit for straightness. Unless the block or head got warped from overheating, and that's how you blew the gasket, then I wouldn't worry.

If the gasket just went cause it's old, then fine. If it went for a reason, then it's probably due to warping from overheating and I would have it re-surfaced.</TD></TR></TABLE>

There is a service limit for straightness. I got it straight out of the helms and posted above. And the motor did get hot.

I guess I'm just going to have to tear into it and see what's going on

 

I believe that limit is just the amount of material you can take off before it starts to get too high compression and the valves start getting too close, etc.

 

I don't think that it is, but I could be wrong.

here is the actual pic from the helms.

One thing that I think is funny is how the new limit is .003" where the service limit is .004". Not a lot of room for error there. Thats why I wonder if it really is that important.

 

Oh yeah, looks like ur right. i never knew there was a limit to how warped it could be.

 

i just did my head gasket (because i THOUGHT it was blown... it wasnt) and i just cleaned the block and head with a green rotating brissle wheel thingy... dont know its name. it worked great (i used arp's and a y8 hg), been boosting 7psi since and no issues.

dan

 

If i were you i would just replace the headgasket with an A6 one and call it a day. You could also measure the deck straightness when u pull the head off to see if its within its service limit or not.

 

Here is what you do. Since you have to change the gasket regardless, just check the warp after you clean the head and the block. If your head and block are crazy warped then just get your other motor done instead of milling the head and block. That will be a pretty penny. If its not warped too bad then whip a gasket in it and drive it till your ready for the other motor.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by highflyinhonda &raquo;</TD></TR><TR><TD CLASS="quote">Here is what you do. Since you have to change the gasket regardless, just check the warp after you clean the head and the block. If your head and block are crazy warped then just get your other motor done instead of milling the head and block. That will be a pretty penny. If its not warped too bad then whip a gasket in it and drive it till your ready for the other motor.</TD></TR></TABLE>


That was exactly what I concluded this morning lol. I went and picked up a cheaper felpro composite and I'm just gonna go for it. Hopefully it'll work out good, if not I'm out $27, not bad.

In the mean time I'll still be chugging along on my other build.