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nudemetalz
26th October 2005, 21:04
Gidday Peoples,

I now have the NZ-250 head off the barrel to replace the head gasket.
It wasn't too difficult a job.

I finally have a genuine workshop manual arriving tomorrow so I can get all of the camshaft bracket torques as well as the head torques info.

However I have noticed that there looks like a sealant-like residue on the top of the barrel. In my experiences you don't normally use any gasket-glue on head-gaskets.
Am I wrong here and should I use a sealant as well?

Also I checked the head and no dreaded cracks thank goodness !!

Motu
26th October 2005, 21:16
What does your new gasket look like? Some have sealer built in....

Bonez
26th October 2005, 21:17
It's just head gasket material burnt onto it.

nudemetalz
26th October 2005, 22:09
Mine's the genuine Suzuki 3-gaskets-to-1 type.

Ah okay, thanks Bonez, makes sense 'cause I've never used bonding agent before and was certain you don't because of the pressures involved.

FROSTY
26th October 2005, 22:21
some mechanics use a smidge instyant gasket--dunno why

Motu
26th October 2005, 23:07
For the old Hemi Valiants the gasket set came with a note to use Hylomar.I still use Hylomar for head gaskets with suspect surfaces.We did a Chrysler Neon head gasket last year (and the clutch yesterday) and with the gasket set Continental Cars supplied a spray can of sealant....Chrysler's fix.I also use a can of copper gasket sealant on some head gaskets - so yes,sealants are commonly used,and often recomended by the dealers,and the gasket manufacturers.

nudemetalz
26th October 2005, 23:27
Thanks, Motu.

When I get the manual, I'll see what Suzuki spec for it.

Brian d marge
27th October 2005, 01:57
To seal or not to seal ...as has been said allready some gaskets are supplied with sealant others arnt ....It depends on the surface and the pressures involved low compression engines ( cooking engines )generally be sealant free, Though if the call out on the head surface then sometines they run a ring of sealant ....
Sealant slows the heat flow ...( on my Enfield and CR I dont use head gaskets ,,, just a lapped surface ,,,)

If you are worried about the flatness of the head , you can run a smear of sealant ...though place the sealant back from the edge as it is a lube i.e slippery and the casket can tend to seep out into chambers ....

Please becareful when using a torque wrench on cam cap bolts .... the threads that the bolts go into ,,can strip v easily ....

One final thing Dont use sellleys no more nails ...I had an old hilman avenger,,I couldnt be arsed fixing the head ,,,,so I threw away the head gaskets ,,,,applied a ton of no more nails ,,,,,Work ...its was tight as a gnats chuff...so tight in fact that a year later ,,,when I decided to keep the ole girl going a bit longer ,,,,I had to remove all the head bolt and use a bottle jack off the firewall the break the seal ......Damn good stuff that selleys no more nails ...wonder what else its good for.......

Stephen

nudemetalz
27th October 2005, 08:20
To seal or not to seal ...as has been said allready some gaskets are supplied with sealant others arnt ....It depends on the surface and the pressures involved low compression engines ( cooking engines )generally be sealant free, Though if the call out on the head surface then sometines they run a ring of sealant ....
Sealant slows the heat flow ...( on my Enfield and CR I dont use head gaskets ,,, just a lapped surface ,,,)

If you are worried about the flatness of the head , you can run a smear of sealant ...though place the sealant back from the edge as it is a lube i.e slippery and the casket can tend to seep out into chambers ....

Please becareful when using a torque wrench on cam cap bolts .... the threads that the bolts go into ,,can strip v easily ....

One final thing Dont use sellleys no more nails ...I had an old hilman avenger,,I couldnt be arsed fixing the head ,,,,so I threw away the head gaskets ,,,,applied a ton of no more nails ,,,,,Work ...its was tight as a gnats chuff...so tight in fact that a year later ,,,when I decided to keep the ole girl going a bit longer ,,,,I had to remove all the head bolt and use a bottle jack off the firewall the break the seal ......Damn good stuff that selleys no more nails ...wonder what else its good for.......

Stephen

Thanks, Stephen.


Looks like it's had the red sealant in there. I'll prob do that again.

Cheers

nudemetalz
27th October 2005, 20:02
Alrighties.....

Got to the bottom of it with some info..

New Genuine Suzuki & Kawasaki head gaskets are manufactured with a sealant already in it, so when torqued down and some heat is applied (ie running the engine !!) it seals itself.

Sealant should only really be used when reusing a head-gasket.

Feel free to tell me I'm wrong but I got this from a respected bike mechanic in Welly.

Cheers

Rhino
27th October 2005, 20:16
Sealant should only really be used when reusing a head-gasket.

Cheers
Reusing a gasket is a last ditch choice, and I would never reuse a head gasket. The bike would wait until I could get a new one.

Ixion
27th October 2005, 20:26
Perfectly acceptable practice with the old solid copper head gaskets. You just anneal them first.

nudemetalz
27th October 2005, 20:33
Yes, but with the NZ250, the genuine gasket was only $45.00, not really necessary to reuse at that price. Mind you, don't ask me what a 1000K5 one costs though.....

Motu
27th October 2005, 20:55
Certainly not a good idea to reuse a headgasket - but silver paint is the trick if you have to.

I had to make my own headgaskets for my BSA M20 - my mother got me some sheet copper from her work (handy things are Mums),it was about 2mm thick,and I cut it out to fit.Then I had a gasket maker make me a couple of copper/asbestos ones - of course once I had done that,then Bill Russell had a big clean out sale and I found half a dozen M20 gaskets sets,complete with headgaskets.

geoffm
27th October 2005, 21:25
I( used to get gaskets for the FZRs from Shuk Engineering - they will make a gasket for anything and a lot less than OE. In Bruce Maclaren Road in Henderson IIRC.
Geoff