KZ550 Head Gasket

Hey everyone
I have a 1981 KZ550 that's been leaking a little from the head gasket for a while. This season the leak has gotten worse to where it's losing a quarter of a quart of oil every week. I've asked around for quotes from shops who can repair it and the ones that will work on it are quoting me 800-1200 dollars which far exceeds the value of the motorcycle. I did my valve cover gasket over the winter but this is a lot more involved project. I guess my question is is this a job that a person with average mechanical skills would be able to complete without screwing the entire engine up? I really like the bike and I'd hate to get rid of it but I won't be able to ride it much longer with the leak.

I didn't know what the Hell I was doing the first time I took a motorcycle head off... a mid 60's twin Triumph. LOL.
I was 18.....
With a real factory service manual, to me, written in old world King's English (amusing ) and a few evenings of reading and dry testing before the whole process.... I started it after school on a Friday evening and was driving the bike Saturday night!!
I got it working just fine.
Although the DOHC KZ bikes are superior and a tiny bit more complicated, and assuming you are also of average wrench spinning capability... I bet you can do it too.

Do it yourself and spend that money on goodies for the bike. Like I always say, there's a certain satisfaction in knowing what's between your legs.
Steve

Have you tried retourquing the head? you need a long reach socket and torque wrench, follow instructions in manual regarding the nut tightening sequence. If loose then up the tourque in several steps. You'd be surprised how much the stud tension can relax over the years. Does it leak oil at the bottom base gasket too?

If you need to replace the head gasket, you can do that yourself, study the manual first. A valve check and shim and grind-in would be good to do at the same time.

Valve guide seals too.
Steve

Thanks for the replies. I have only tried tightening down the 4 head bolts closest to the sides of the engine because that's where most of the leak is coming from. They were over the 17 ft lbs recommended by the climber manual, however I know the climber manual is notorious for bad torque specs. Does anyone have the correct torque specs for the 81 Kz550 LTD head bolts?

Do them all or you run the risk of warpage.
Steve

Here are the torque specs from the KZ400/KZ500/KZ550 Kawasaki Service Manual (1st image below). The manual contains the torque table (2nd image) and a supplement torque table (3rd image) for the 1982 KZ550. It appears that both tables contain the same specs for the cylinder head fasteners.

You mentioned “bolts” near the sides of the engine. Are you sure they really are bolts or are you tightening the nuts that are on studs? I ask because the bolts are 6mm and the studs are 8mm; they use different torque values. Ed

Thanks Ed. You're right they are nuts and not bolts. I'll try retorquing all the nuts and see if by some miracle that is the problem. I caught a nail in my tire while coming home from work the other day so it doesn't look like I'll be riding around until I can get that repaired anyway

Don't take the "nuts" off unless you're going to tighten them down the right way.
Steve

Ok so I loosened them all up and retorqued them using the pattern in the manual. The good news is it's not leaking any worse but it didn't fix the existing leak. I suppose this means it's time for a new head gasket

Yup.
Steve