Topic: brandEn's leak free top end thread = Tips, Tricks and Suggestion encouraged

[brandEn]

Hey that seems like a pretty good idea. Did you come up with that yourself? I had Bronze sleeves installed in my head.

[tlbranth]

I don't know if this will be of any help in the seal/don't seal conversation but here goes. Waaay back in the 70's sometime, I had the cylinder head off and asked at the dealer how to stop leakage out of the head gasket. He sold me a gasket that had some kind of 'stickum' on it and told me it seemed to solve the problem. I don't remember if the gasket was OEM or not. As I recall it "looked" OEM. Anyhow, it seemed to solve the problem. I don't notice leakage anymore. I'm surprised because the head and block probably don't expand at the same rate - the head being hotter - and it seemed to me the glue would come unstuck. But it seems to work. So maybe some goop would help. Love to hear the results. Great thread.

BandEn - your work is very impressive for someone who's 'not an expert'. I think you'll be successful with your rebuild with all the care you're taking.
I have a question about your paint. Is that Duplicolor on the engine? That's pretty much the look I'd like to go for.

[flybox1]

Hey that seems like a pretty good idea. Did you come up with that yourself? I had Bronze sleeves installed in my head.

Not my idea...70CB750 mentioned that one.
Just figured it should be included here.

[brandEn]

I don't know if this will be of any help in the seal/don't seal conversation but here goes. Waaay back in the 70's sometime, I had the cylinder head off and asked at the dealer how to stop leakage out of the head gasket. He sold me a gasket that had some kind of 'stickum' on it and told me it seemed to solve the problem. I don't remember if the gasket was OEM or not. As I recall it "looked" OEM. Anyhow, it seemed to solve the problem. I don't notice leakage anymore. I'm surprised because the head and block probably don't expand at the same rate - the head being hotter - and it seemed to me the glue would come unstuck. But it seems to work. So maybe some goop would help. Love to hear the results. Great thread.

BandEn - your work is very impressive for someone who's 'not an expert'. I think you'll be successful with your rebuild with all the care you're taking.
I have a question about your paint. Is that Duplicolor on the engine? That's pretty much the look I'd like to go for.

Thanks!
No its not duplicolor its PPG gloss black aerospace paint

[PeWe]

I don't know if this will be of any help in the seal/don't seal conversation but here goes. Waaay back in the 70's sometime, I had the cylinder head off and asked at the dealer how to stop leakage out of the head gasket. He sold me a gasket that had some kind of 'stickum' on it and told me it seemed to solve the problem. I don't remember if the gasket was OEM or not. As I recall it "looked" OEM. Anyhow, it seemed to solve the problem. I don't notice leakage anymore. I'm surprised because the head and block probably don't expand at the same rate - the head being hotter - and it seemed to me the glue would come unstuck. But it seems to work. So maybe some goop would help. Love to hear the results. Great thread.
#

I got same kind of head gasket beginning of the 80's. Hondaman has written about this kind of gasket in a thread, OEM Honda.
Last time I mounted the head, almost 2 weeks ago I sprayed the fiber gasket on both sides with Permatex Copper spray gasket. Covered the part of the 8 oil holes that are exposed inside the head-cylinder when no o-rings are used here. I thought that the spray could fall off into the oil. I masked them with old o-rings

[Hon3ybadger]

Just my luck I find this thread a month after my top end rebuild and a week after my first leaks.

Things I've learned the hard way:
- Athena gasket kits are poorly cut to shape and seem to soak up oil like toilet paper and weep= Total waste of money
- I didn't put any sealant on the pucks and now they seem to drip.
- My top end sounds like wrenches bouncing around in a tool box because I opted to not replace my rock hard cam chain roller with link indents in it.
 

[Stoli]

Hey brandEn, you seem to know your way around the top end. I have a small leak that produces a few drops of oil on the bottom 3 fins of the head (on the very end just to the left of the #1 spark plug).

Here is a thread I started:

http://forums.sohc4.net/index.php?topic=136850.0

I have sealed the threads of the cam studs as well as sealed the pucks with some non-hardening gasket sealer. I also sealed the threads of the 3 valve cover bolts on that end of the cover. There is absolutely no trace of oil anywhere else on the head or cylinders. The only other holes in that area are the cylinder stud in front of the #1 spark plug, and the 6mm bolt next to the spark plug. Can oil come out of that stud or bolt? Anything else I missed?

[brandEn]

Just read your thread and seems like you have your bases covered. If it were mine I would suspect that 1/4 - 20 bolt that is installed though...

[Stoli]

If it were that bolt, or perhaps that cylinder stud, how would oil be getting there and is there a way to seal the washer?

[brandEn]

If it were that bolt, or perhaps that cylinder stud, how would oil be getting there and is there a way to seal the washer?

Sorry, but I just don't know.

[01Thomas]

Bump so I can find this thread later.

~T

[oldhatt45]

BrandEn,
I thought your information is Excellent.

I have put the whole thread into a Word Document to make it easy for folks to Download, Printout and have handy when they (and me ) go to do a Top Ed job.

I have attached the document below, for those like me that want the info handy. 
Hope you don't mind.

Thanks Again,

Charlie

[brandEn]

Well that is pretty cool! Thanks! I am happy this thread has been helpful to so many people. It really started just to help me make sure my project was getting done correctly. After putting in the work and cash building an engine just to have it leak is a horrible feeling.

[evanphi]

Some day down the line I will have some use of this thread! I think my pucks leak, or maybe the valve cover... but its only a little bit and I don't want to remove my engine.

Once I have a second bike to ride I will be fixing that!

[Chad]

This might be a dumb question... did you use use gasket dressing on the valve cover gasket? I feel like I saw somewhere not to, but I can't find the thread.

And one more question... to remove the cam tower studs, did you just double nut them?

[lucky]

I am surprised no one has mentioned resurfacing the head or cylinder block and the head is often warped from heat curing.  I had this on my 73 CB750 and asked for a minimal resurfacing of .005 per Hondamans instructions and the head was perfectly flat after.

Also, I did not use any goo in my engine except to seal the rubber pucks which shrink in time and end up leaking.  I do not like sealant as I can not work fast enough to get everything torqued down fast enough.  With heavy duty studs, two flat matting surfaces and O-Rings of the correct thickness for oil passageways there is no reason for a leak to develop at least on the older style heads.  Getting the correct orings is a big deal.  Do not automatically assume the ones with your kit will work as intended.

Instead of those rubber "pucks" why not just use aluminum pucks the correct size?

[flybox1]

Instead of those rubber "pucks" why not just use aluminum pucks the correct size?

Not one mention of a source for these alu pucks, why they are 'preferred' above what HONDA engineered or how to properly seal them 

There's nothing wrong with sealed pucks of the proper thickness.
Done properly it'll last another 20+ years.

[brandEn]

This might be a dumb question... did you use use gasket dressing on the valve cover gasket? I feel like I saw somewhere not to, but I can't find the thread.

And one more question... to remove the cam tower studs, did you just double nut them?

yup, a little bit of Gasgacinch.

Just as a quick update to this thread. I used the Cycle X MLS gaskets on my K4 and much prefer these because they don't need any sealers. I know they are expensive compared to regular gaskets but they are nice and reusable.

[brandEn]

also, yes just double nut the studs to remove them. Those come out pretty easy from my limited experience.

[welard]

I have attached the document below, for those like me that want the info handy. 
Hope you don't mind.

Thanks Again,

Charlie

Thanks heaps for that Charlie...that would have taken a hell of a lot of cut 'n paste, but a great idea to save the document.

Awesome thread branden...cheers...saved carefully for later reference.

[evanphi]

Some day down the line I will have some use of this thread! I think my pucks leak, or maybe the valve cover... but its only a little bit and I don't want to remove my engine.

Once I have a second bike to ride I will be fixing that!

Looks like I spoke too soon. Head gasket leaks now, and a little puddle forms under the bike after I park it. Winter project, here I come...

[koendd]

Some day down the line I will have some use of this thread! I think my pucks leak, or maybe the valve cover... but its only a little bit and I don't want to remove my engine.

Once I have a second bike to ride I will be fixing that!

Looks like I spoke too soon. Head gasket leaks now, and a little puddle forms under the bike after I park it. Winter project, here I come...

sounds like my F2 

but probably not head gasket but the pucks as you said before. Will be tackling mine soon

[evanphi]

Some day down the line I will have some use of this thread! I think my pucks leak, or maybe the valve cover... but its only a little bit and I don't want to remove my engine.

Once I have a second bike to ride I will be fixing that!

Looks like I spoke too soon. Head gasket leaks now, and a little puddle forms under the bike after I park it. Winter project, here I come...

sounds like my F2 

but probably not head gasket but the pucks as you said before. Will be tackling mine soon

Nah, it is definitely the head gasket. Pucks were just a splashy-leaves-an-oily-film-on-everything leak. This is a dripping-when-on-the-sides-tand leak.

[markreimer]

The head sits maybe .030-.050 off the cylinder deck. The knock pins were not removed before I tried the head on the cylinders, so if I have the wrong length ones, they came with the bike that way.  Would definitely explain the oil all over the motor, and the very low compression,( before I took motor apart), having the head held up that way.

I'm doing my second engine rebuild on a cb750 K4 and my knock pins also sit above the surface by about the same amount. The first time I did a head job I had no problems with leaking head gasket or low compression. It seemed to work fine as-is. Perhaps it's because they are slightly tapered at the top, so they may slide into the head?

I have the engine apart now with the dowels in. I'll go check and see if the head sits flush without a gasket, with the pins poking up a bit.

[markreimer]

Yup, definitely doesn't sit flush with those pins in it... Maybe I'll leave them out myself then.

If you leave the pins out, I assume you leave the rubber rings that go around them as well?