Myst8u

I need to replace my valve cover gasket and o rings and figured I would buy a full gasket kit that way I'll also have a head gasket and extra stuff for the future. I see that a lot of people prefer Honda OEM head gaskets however, I would like a MLS head gasket and I'm not sure but believe my OEM gasket would be composite since it's a 1994 Honda Civic DX, D15B7 engine. Does Honda make OEM head gaskets for my engine that are MLS or is it only composite? I would like to have a MLS head gasket because to my knowledge it's more durable. After seeing the prices of OEM gasket kits that don't include head gaskets, I'm thinking of getting a Fel-Pro Gasket set and purchasing a honda OEM Head gasket separately if I can be sure it's MLS. Any advice would be appreciated.

Wankenstein

Search HondaPartsNow website. Honda genuine (oem) parts only.

D17VTECPOWER

iTrader: (1)

I used OEM Honda head gaskets the couple times I needed to replace mine because I know I can count on them and the price difference between an aftermarket and OEM head gasket on Amazon was negligible, but Felpro makes good gaskets too. Honestly most MLS head gaskets are good from my experience. The most important thing is to make sure the head and block are clean, dry, and flat before reassembly and to torque the bolts correctly. Hope this helps

Myst8u

Sound advice said well. I think then that I'll definitly order a Fel-Pro head gasket for the future. Thank you!

Wankenstein

Personally, I wouldn't want to chance having to do a headgasket twice using an aftermarket gasket when a Honda genuine part is only $20 or so more. Every millimeter of specification counts.( no dong reference.. lol).

Myst8u

When I went looking for a genuine Honda gasket all the ones I found were either almost $100 or more. I ended up getting a ishino stone gasket set on eBay on sale at $107, the shop is run by eastover auto parts store in maryland and I really like them so far. I've heard really good things about Fel-Pro head gaskets but for now, I might just stick with the composite stone one that came in the kit. I wanted an mls because I heard they're more durable.

Colin42

The Honda one is mls.....

D17VTECPOWER

iTrader: (1)

That's what I thought, but I wasn't sure since I never did a head gasket on that engine. In my opinion it wouldn't be a good idea to replace the stock MLS gasket with a composite gasket though, the thermal expansion properties will be different than what the engine was designed for and might cause problems or premature failure. Also, the OEM head bolt torque specs are for the gasket that the engine came with, not something made of a different material. I don't know that it would actually cause a problem, but I wouldn't take that risk.

Wankenstein

Your car engine oem head gasket (composite): https://www.hondapartsnow.com/genuin...1-pm5-s02.html

Read reply #8 in this thread: https://honda-tech.com/forums/road-r...d16a6-1695346/

This seems to be the bulletin: https://workshop-manuals.com/honda/c..._gasket_leaks/

Ezone might know for sure but he has not responded much lately. Call your local Honda dealer, Majestic Honda or HondaPartsNow..they may have info?

This read may help as well (attention to ezone's replies):
https://www.civicforums.com/forums/3...lpro-good.html

Myst8u

That last article I read before I made this thread, it did help somewhat. I realize HR Puffinblunts( what a great name lol) has a good point it's just a verse for me, maybe it's not a good idea for me to put an MLs gasket in my engine for now since the stock head bolts were built to go with a composite gasket. I wonder if in the future getting different head bolts would remedy that, or if it won't change anything. Since I already have a head gasket that came with my ishino stone set I might as well use that one since it's stock. Forgive my ignorance, I am starting out learning about all this and want to be sure of what I'm working with. Thank you for all your help.

D17VTECPOWER

iTrader: (1)

The problem wouldn't be the bolts themselves, it would be the spec bolts get torqued down to. A lot of time and money was put into figuring out how tight the bolts should be for the best possible durability in the stock configuration. When you change things like this, you can cause problems. For example, a MLS head gasket may require more clamping force (tighter bolts) than the composite gasket to seal correctly, so the stock spec may not be tight enough. And if they need more torque, how much more would they need? And could the stock bolts and bolt holes handle the extra torque? No way to know unless the gasket comes with instructions that include revised torque specs. And whoever made the gasket most likely didn't put as much time and money into figuring out the correct torque specs as Honda did.

And even if you figure out the torque specs, the other potential problem I can think of is thermal expansion. The head and block expand as they warm up. A lot of time and money was put into figuring out thermal expansion rates and ensuring that thermal expansion and heat cycles won't cause a failure. Installing a gasket of a different material could possibly cause problems with thermal expansion since the engine was not designed for the thermal expansion properties of any head gasket other than what it came with.

I am not an engineer and I do not know all the possible implications of using a MLS gasket since I didn't design the engine, but I would not personally take that risk if this was my car, I would use an OEM or high quality OEM style gasket. The only way I would consider using a different material is if a reputable company created an upgraded gasket that has been tested and found to work correctly and actually be an upgrade over the stock gasket.

Myst8u

I agree. You raise many good points. I suppose if I truly do want to replace my gasket in the future with an mls one, that I would really have to be comfortably sure that what I chose would be able to provide proper torque specs and compensate for heat expansion difference. It is a lot to gamble on. As long as the composite gasket I have from Ishino Stone is good that should do fine.

D17VTECPOWER

iTrader: (1)

One thing you can do that might improve durability though is replace the factory head bolts with ARP head studs. People say they don't do anything unless you are making big power, but I think they might add a bit of durability from a crude test I did. I did a test on a junk D17A1 that I was replacing and scrapping anyways where I drained the coolant and badly overheated it several times, literally to the point of melting plastic parts and dying out. 350+ degrees. But you know what, it never blew the head gasket and when I tore that engine down and checked the head and block for warps, it was completely flat. Not a scientific test, but from past experiences with these engines I am pretty sure the gasket would have blown and the head would be warped if it was held down by stock bolts.

Myst8u

I've seen people talk about ARP head bolts in other head gasket threads and wondered about them. I haven't ordered new head bolts yet so I just migt try the ARP ones. Is it ok to reuse bolts? I've seen many people say that it's fine for like 2 to 3 more uses but then there are others that say it's better to get new ones any time you change the head gasket. I'm kind of torn on it.

D17VTECPOWER

iTrader: (1)

You can reuse the old bolts, the suggestion to replace them only applies to torque to yield bolts. Those bolts are turned a certain number of degrees after they are torqued down to stretch them. The problem is once those bolts are stretched once they can't be stretched the same way again. Your bolts don't stretch so it's fine to reuse them. Just make sure to clean them up reasonably well and lightly oil the threads before you screw them in. This will help them torque down smoothly and evenly without binding.

Myst8u

I wondered about that, thank you. I knew tty bolts most likely needed replacing but wasn't sure if regular bolts stretched or not. I also have some gasket seal for when I'm ready to replace the head gasket but I've seen conflicting opinions on that as well. Is it really only needed if the block or head is uneven or scratched? I opted for gasket seal over copper spray cause a lot of people seem to advise against that.

Wankenstein

You can reuse the bolts as they are not stretch bolts a.k.a TTY bolts. I used new honda oem head bolts as they only cost $25 for 10 bolts and I felt for the minimal cost it made sense. Below is a great (2-part) video on good practices for doing any head gasket replacement. One very important tip is make sure the head bolt (threaded) holes in the block is as dry as possible before inserting the head bolts. However, you can lightly oil the bolts threads prior to insertion.

Myst8u

Everywhere I've been looking 10 OEM honda bolts cost much more than $25 so I've considered just reusing my old ones since they're not tty. Though the ARP ones sound intersting but this being my first job I might just want to stick with what I got. Thank you for the link! I learn best by watching others then doing it myself and that guy was very thorough in explaining things, especially diagnostics.

D17VTECPOWER

iTrader: (1)

I wouldn't use any type of spray on the head gasket, it is not needed. The gasket will seal perfectly on its own if the surfaces of the head and block are flat and it's installed correctly. What exactly do you mean by "gasket seal"? You mean RTV silicone? If so, don't put that on the head gasket either. If the head or block is uneven or significantly scratched using that stuff won't help, it would need to be resurfaced.

D17VTECPOWER

iTrader: (1)

If you choose to go with ARP head studs here is a video on how to correctly install them. It's really not hard and it may help improve durability a little bit. Basically the idea is that those studs are stronger than stock bolts. Also, they torque down more evenly since the whole bolt isn't twisting in the holes in the block, but rather you just torque a nut onto the end of the studs. Thirdly, they can help because they can get torqued down harder than bolts because you have full thread engagement with the studs in the block since you thread them into the block all the way before torquing the nuts. I torqued my studs to 60 ft lbs as per ARP's instructions rather than the OEM spec of 49 ft lbs and as I said it passed my crude durability test, so I must have done something right.

Myst8u

My apologies, what I have is permatex Red RTV Gasket Maker. Is it not good to put a little bit on some spots on the edges of the head gasket to help it seal? I only got it just in case because I've seen some people use it to help seal.

D17VTECPOWER

iTrader: (1)

Don't apply any sealants to the head gasket unless either the service manual or the gasket's installation instructions say to, and I haven't seen any that do.

Myst8u

Understood. Thank you!

D17VTECPOWER

iTrader: (1)

Any time. If you have any more questions feel free to ask

Wankenstein

You may run across videos or forums where people use a copper spray on their headgaskets during replacement: http://www.sccoa.com/forums/showthre...y-head-gaskets That spray is not needed as D17 mentioned. The most important thing is bringing the head to a machinist to make sure it's not warped out of manufacturer's tolerance and is glass smooth cross-hatched milled. A machinist can also check the valves for leaks, the head for cracks and can hot tank clean it if you want to pay a bit extra. IMO, while it's at the machinist's it's a good time to get the valve stem seals replaced. When you take the head off do not lay it flat on either the block facing side or the valve cover facing side. You will most likely need a new intake manifold gasket as the old one will be brittle and tear apart. The metal exhaust manifold may be okay to reuse and are cheap to replace anyway.

If you clean the old headgasket off the head yourself use a razor blade and brake cleaner..do not dig in too hard and scratch the mating surfaces on the block or head. Do not use scotch bright pads, sandpaper or similar on the block as the shavings can potentially get into the internals via the cylinders and ruin the engine.

You're right those headbolts are more expensive..around $6.50 each on Honda genuine parts sites.