cylinder head gasket

[longgreensilverado]

this morning on my way into work i smelled oil burning. i noticed the head gasket had a good leak all accross the front of the engine. This has never leaked before and i know the bolts are tight.

has anyone ever replaced this gasket and will i have to remove the cams along with the cam chain to get to it?

thanks in advance.

[Road_Clam]

this morning on my way into work i smelled oil burning. i noticed the head gasket had a good leak all accross the front of the engine. This has never leaked before and i know the bolts are tight.

has anyone ever replaced this gasket and will i have to remove the cams along with the cam chain to get to it?

thanks in advance.

Welcome to the club, you have a blown HG. Common problem on a 25+ year old bike. Replacing the HG is a big job, make no mistake, but it's do-able for the averasge garage mechanic. Yes the cams have to be removed, the cam chain however does not. If you do take on the project, do yourself a BIG favor and yank the cylinder and replace the base gasket as well, it's not too much more work. You WILL disrupt the base gasket seal in the process of removing the HG.

[tkent02]

Odd for it to suddenly start leaking bad enough to smell oil, without seeping for years first. Are you sure it's not flowing down from the tach drive or the valve cover gasket?

[longgreensilverado]

ok to answer the first response i do have a clymer manual from the original owner. i just haven't looked at it for this task yet. and thank you


to the second response:
i replaced the tach drive seals and added a little hi temp rtv last year and has stayed dry since. the valve cover started leaking last week on the left (clutch lever) side of the bike, but has been very little. on my last oil change i used semi synthetic oil. i think the semi synthetic oil is the cause of this since it has never leaked before.

[49er]

ok to answer the first response i do have a clymer manual from the original owner. i just haven't looked at it for this task yet. and thank you


to the second response:
i replaced the tach drive seals and added a little hi temp rtv last year and has stayed dry since. the valve cover started leaking last week on the left (clutch lever) side of the bike, but has been very little. on my last oil change i used semi synthetic oil. i think the semi synthetic oil is the cause of this since it has never leaked before.

Changing to a semi synthetic oil is probably the cause of your leak. What model GS are you running and how many mls/kms on it?
Most people only torque their head bolts up twice between top end rebuilds. Through may thousands of heat cycles ( some quite extreme), there is extra give/crush on the gasket's surface. It's good practice to re-torque every so often to delay the weeping that occurs eventually with old age. I usually re-torque every 20,000kms which coincides with a valve clearance adjustment.

[longgreensilverado]

the bike is a 1980 gs850g with 35, ooo miles on it. i definately think the oil is waht caused the leak. when i get home later on I will wash the bike very thoroughly with engine degreaser and a garden hose. (low water pressure prevents water from getting in). i will dump the oil since it has 1500 miles on it and switch to 15wt 40 for the rest of the week and see what happens. if the leak goes away or slows down i will wait till winter to tear it all down. i have had almost 3 good years with this bike and plan on buying a new bike in the spring, but before i sell it i want it to be in good running condition with no leaks.

thanks for your help

[feelergaugephil]

It took me 6 hrs from start to finish, which included base gasket too.

[longgreensilverado]

well last night i cleaned the bike twice to make sure i got rid of all the excess oil. I drained the oil (which was synthetic). i replaced teh oil with shell rotella 15wt 40 and drove into work this morning and so far so good.

although i think i will go the route of buying a new gasket for the breather cover and cam cover. the breather cover has a faint leak. i will also replace the half moon seals on the cam ends.

i think i will use those realgaskets everyone seems to love

thanks again for all your help.

[Road_Clam]

on my last oil change i used semi synthetic oil. i think the semi synthetic oil is the cause of this since it has never leaked before.

This is not the reason your gasket let go. Your gaskets have been heating up, expanding, cooling down, shrinking for the past 27 years. They eventually fail. My HG blew exactly 100 mi after my restoration. My bike also sat for over 4 years never even being started. It was simply your gaskets time, grasshopper.........

[DanTheMan]

This is not the reason your gasket let go. Your gaskets have been heating up, expanding, cooling down, shrinking for the past 27 years. They eventually fail. My HG blew exactly 100 mi after my restoration. My bike also sat for over 4 years never even being started. It was simply your gaskets time, grasshopper.........

Agreed, Mahster........
My bike started weeping at about (aboot foor yooooo Canucks) around 45,000 miles, it blew oil all over my right pants leg aboot (again for the Canucks..:-D), around the 55,000 mile mark. Long hard rides through hot country did it for me, but miles and temp will fiinish those old gaskets off.........just replace 'em all, (if you can afford the time and money), saves the head ache later.
P.S. (and yeah, it's a pain in the butt to do the head job, so you'd better do it right the first time..... )