550 Head Replacement

Hey all,

Unfortunately, I had 2 exhaust studs break off in my head. I was originally going to take it to a machine shop and have them pull it, but I found out that I could buy a used head (with valves) for cheaper than it would cost for them to fix it. I've ordered a head gasket, but aside from that, what else is needed? I've done valve shims, clutch, and other mechanical things, but this is the first time that I've ever done anything like this before, so I want to be prepared with as much information as possible. I have a set of Valve cover donuts and washers in my garage and those will go on with the installation. I would assume that the valve lash would need to be adjusted along with this as well. Any help is greatly appreciated.

Thanks!

 

If you're keen you can strip the head, lap/grind in the valves (test for leakage), polish the journals then re-fit cam and check/replace shims
Depends on the time you have. It's a full days work I would guess, or longer if you work like I do..

 

Don't know if it would apply with your bike, but I was talked into "doing the valves" on a car when have the head gasket replaced and it immediately started using a log of oil. The mechanic told me that the oil was now leaking by the rings since the valves were sealing so well. Went from using no oil to a quart every 250-300 miles. Rather than argue I just sold the car to someone willing to keep adding oil and they ran it for years.

 

I ended up buying a complete head, minus cams. I had debated on whether I should throw some fj600 cams in it, but decided to just reuse my cams. The head is off of a bike that was running. I was mainly concerned about additional gaskets and seals so I didn't have to do it twice. The damn head gaskets on these are so expensive that I didn't want to have to replace that again because I skimped on hardware or other seals.

 

Just make sure that you get the correct cam-chain tunnel gasket. The one that comes in the Athena kit is too thick. You'll also need two new special-sized copper crush washers to seal the head oil galleries on the right-side head bolts (you can just anneal the washers you have if they are serviceable), new YICS passage o-rings, and new special-sized oil gallery o-rings. Getting a top end gasket kit is highly recommended over just getting the gaskets separately. Chacal has the correct kit in stock.

 

K - IIRC there is no separate cam chain tunnel gasket on the 550 - good point though on a top end kit, then you also get valve stem seals if you're keen for a 'full overhaul'.

J