Changing head gasket

Kernel · Post by **Kernel** » Tue Jan 09, 2007 6:01 pm

Had a few problems with the beast dumping coolant. So finally have got round to checking her out.
First things to check Thermostat and rad cap, had both of them out and put them in a bowl of boiling water, both opened up. So that leads to the dreaded head gasket failure.
Gonna change it at the weekend, but not something that I have ever done before, so any advice on do's and don't's would be appreciate, I have a good idea of what I have to do, but there are somethings that I am not going to know.
I assume if I have to have the carbs of will have to balance them out after.

Here are a few pics of the head.

You can notice some leakage around the head, so it looks like it is likely.

Oh and ignore the rusty downpipes.

hipringle · Post by **hipringle** » Tue Jan 09, 2007 6:27 pm

Is the leakage not coming from higher up at the rocker. It looks like its just oil seeping out not water. I,m sure someone will advise on the procedure but I,d be inclined to check the waterpump first if its poss (dont know much about these I,m afraid).
Is the system pressurising when the bike is running, have you noticed any bubbles coming up to the rad cap, if so then that could be a sign of head gasket failure.

Kernel · Post by **Kernel** » Tue Jan 09, 2007 6:40 pm

There are some bubbles when the bike is running, it has done 25,000 miles so I would say it is due anyway.

hipringle · Post by **hipringle** » Tue Jan 09, 2007 6:46 pm

I think when I was looking around the site I read that they can go at 20K so if it hasnt already been done its probably caput, especially with it bubbling.

Hope someone else can maybe help

Kernel · Post by **Kernel** » Tue Jan 09, 2007 6:53 pm

She still runs sweet as a nut tho.

Post by **cargo** » Tue Jan 09, 2007 7:10 pm

Just where exactly is this coolant being dumped from ?

There are little drain holes form where the spark plugs go that drain oil/water it can look like a head gasket is gone when it's only one of the rubber seals on the cam cover.
The little holes exit just under the exhaust ports.

Replacing the head gasket is straightforward (and you won't need to balance the carbs).
Truth be told it's easier to drop the engine out to do a head gasket.

Post by **masterofinsanity** » Tue Jan 09, 2007 7:13 pm

if she still runs sweet i would hold fire, is your coolant ok and the rads not blocked. try running a hose through the radiator make sure its not blocked.you will find tiny bubbles appear under the rad cap when its on its way out, you sure you haven't overfilled the coolant???

Post by **cargo** » Tue Jan 09, 2007 7:41 pm

masterofinsanity wrote:if she still runs sweet i would hold fire, is your coolant ok and the rads not blocked. try running a hose through the radiator make sure its not blocked.you will find tiny bubbles appear under the rad cap when its on its way out, you sure you haven't overfilled the coolant???

I agree.
you can lose coolant in lots of ways and you don't want to replace a head gasket and still have the problem

Jackson · Post by **Jackson** » Wed Jan 10, 2007 9:02 am

Is there any moisture in your oil? Run the bike for a few mins and then look in the oil level window, if its steamed up then theres water getting in - another sign of headgasket.

Likewise with the coolant, is it oily? (pour some out of the expansion tank and see if you can see oil streaks in it)

all the best

Post by **masterofinsanity** » Wed Jan 10, 2007 9:27 am

Jackson wrote:Is there any moisture in your oil? Run the bike for a few mins and then look in the oil level window, if its steamed up then theres water getting in - another sign of headgasket.

but at this time of the year a lot of damp and condensation can show similar symptoms in the oil level window so don't be fooled.

Post by **cargo** » Wed Jan 10, 2007 10:12 am

masterofinsanity wrote:
Jackson wrote:Is there any moisture in your oil? Run the bike for a few mins and then look in the oil level window, if its steamed up then theres water getting in - another sign of headgasket.

but at this time of the year a lot of damp and condensation can show similar symptoms in the oil level window so don't be fooled.

Once again I agree.
Also moisture can collect in the oil side if the bike has been used for short runs.

Before tackling the head gasket eliminate every other possibliity.
I've raced zxr400s for nearly 7 years and I've never seen one with a blown head gasket

Kernel · Post by **Kernel** » Wed Jan 10, 2007 6:02 pm

There is no moisture in the oil, nor oil in the coolant.
The water is leaking from the over flow pipe of the reservoir tank, and when I fill the rad, it drops over few miles and then pisses out the resevoir overflow.
The engine is nearly out now so gonna go the head gasket regardless, although I will check the water pump, any idea how to test and if kapt how much is a replacement.

Post by **masterofinsanity** » Wed Jan 10, 2007 9:53 pm

sounds like the system is getting pressurised so could be then.

Kernel · Post by **Kernel** » Thu Jan 11, 2007 6:24 pm

Got the head off now, and looking closely can see the head gasket has blown on cylinder 4. So now gonna clean up the head and piston, get the new gasket and fit it. Thanks for the advice that have been given.

Kernel · Post by **Kernel** » Thu Jan 11, 2007 6:48 pm

Got the head off now, and looking closely can see the head gasket has blown on cylinder 4. So now gonna clean up the head and piston, get the new gasket and fit it. Thanks for the advice that have been given.