Head Jobbie

[Falken]

Hi
New to your site, but from the other side of the pond so to speak.

I have a '78 'E' that has a blown head gasket.

Zorsts are off, carbs are off , now down to the dirty work.

Is there anything I need to look out for when taking it down further. I have the manual but nothing makes up for experience of someone who has done it before.

Thanks all the same and nice site.

Rob

[DiverRay]

The big question is are you going to replace the cam chain? If so, just be careful when pulling the rivet holding the link, and have a wire already on each side of the rivet BEFORE you undo it. This way, you keep the old cam chain in until the head has been put back on, and then feed the new chain down and around the crank sprocket.
If you are NOT going to replace the chain, Set the crank to the "C" position, like you are adjusting the chain, and then pull the adjuster out. You then break loose the 10mm head bolts holding the cam gear onto the cams, remove the cam tower nuts, and remove the cams on at a time. You should then be able to remove the head. As above, keep the cam chain above the head with a length of wire.
You did remember to unscrew the ballast resistor so you have the room to remove everything, right??
Welcome to the site, and don't forget some of the guys there in the UK are VERY GOOD, and can help as well!

[prometheus578]

"First explain what a Zorst is"

Need to figger out why the gasket blew in the first place.
Take your head to a specialist and have it checked to ensure that it's not warped.
(My doctor has me do this several times a year. I'm not as warped as I once was... the medication helps)
Also, there was a design change years ago concerning the head gasket.
Replacement gasket set no longer have that inner gasket/ cam chain guard thingie. That has been done away with.
Other than that...
Flip the head on it's side, pour some fuel into the intake and the exhaust ports to see if it leaks past the valves. Might want to lap them in a little if they leak.
Removal and replacement of the head gasket is pretty straight forward.

[fredintoon]

Zorsts

Hi Pro,
you should read this booklet, "Kreck waiter speak Bristle" That's really egg-zorsts, like the back end of a chicken. On a bike they have fat chrome pipes bolted on them.
And, Falken, where in Wilts? I'll be at my sister's place in that county in February '08 for my nevvy's wedding.

[Falken]

Hi Guys
Thanks for the info.

Bike has done 24,000miles , cam lobes are clean and not worn or pitted and chain as far as I can see looks ok(rocker cover off) so I wasn't going to replace the chain.
Do I need to split the cam gears before pulling the cams or is there enough space to lift the chain off once the tensioner is removed and remove the cam & gear in one piece?
Yes ballast resistor and horn are well out of the way.

As far as why head gasket went, I dont know, I bought it as a project bike for something to do with my son, after being bored to death on my GSX750F teapot which never went wrong.

I have a head specialist lined up to check head surface and plane it if necessary (most probably will need it). Gasket was only blowing slightly out of the side of No4 so not gone big time. Have to wait until head is off though for sure.

Fred, I am in Chippenham if you know where that place is.

Will let you know what I find.

Cheers
Rob

[DiverRay]

Rob,
You WILL have to remove at least one "gear" to remove the cams. Be SURE you DO NOT TURN THE ENGINE until the cam towers are loose. If you do, you may be replacing valves.....

[mitch]

Plse Check

If you have oil around your Cylinders plse check the Timing chain adjuster first as they leak and it blows back looking like you have a blown head gasket you just might only have a small oil leak !!!!!
I though i had a gasket problem and it was the adjuster leaking . Might just save yourself some work . 24000 klms is very low for something like that to be going on .
regards
Doug

[79XS11F]

I agree with Mitch ... Make sure the head gasket is in deed blown before you take it off if not already done. Run a compression test. It is however a pretty straight forward job to do if the head must come off. If this is the case you might as well clean up the combustion chambers and piston tops while you can. Once it's back together you will have more even compression among the cylinders that way.
Rob

[TopCatGr58]

Just to add about the cam chain. Perform the cam chain tensioner adjuster procedure, and then with the tensioner plunger locked in place, remove the tensioner, and check to see how much more plunger distance it would have to travel before running out of plunger shaft!

IF it's already near the end of the plunger shaft, then the chain may be stretched near it's limit, and replacing would be in order. But if the plunger isn't pushing in very far, then the chain is probably good to go, and you can just do the head job.

But, hopefully you'll find that your compression test will show good compression? You may want to put the Zorsts and carbs back on to run it up to operating temps to recheck the compression warm. The heat may help expand parts/head to allow leaking vs. cold!?
T.C.

[skids]

Geez, if you are going to take the head off, you might as well replace the valve seals also!

[Falken]

Thanks Guys

I degreased the engine and checked tensioner first to see if it was leaking and also the oil pipe at the rear of the engine to see if oil was running throughto the front , no such luck.

I sprayed the engine with lube and bubbles were popping out of the side of no4 where head joins to the block.

I did buy the bike advertised with blown head gasket.

Will check the tensioner travel though before I take it further just in case chain is stretched.

Cheers
Rob

[trbig]

I think this is an actual first for me to hear of a blown head gasket on one of these bikes. It makes me wonder if whoever had the bike last didn't re-torque after taking the head off and getting it warm? Or maybe looked at the book wrong like me and only tightened them to 14 lbs?? lol. (Hush TC)

Before you laugh... there's 2 spots in my book that look like this...










But those tightening specs are for the previous steps. I actually rode it around like that for quite a while without any problems... but could see where there would be.


Tod

[79XS11F]

Originally posted by trbig
I think this is an actual first for me to hear of a blown head gasket on one of these bikes. It makes me wonder if whoever had the bike last didn't re-torque after taking the head off and getting it warm? Or maybe looked at the book wrong like me and only tightened them to 14 lbs?? lol. (Hush TC)

Before you laugh... there's 2 spots in my book that look like this...










But those tightening specs are for the previous steps. I actually rode it around like that for quite a while without any problems... but could see where there would be.


Tod

If I am not mistaken the 14 pounds is ONLY for the front and back nuts that go on from the underside. DO NOT TORQUE THOSE PUPPIES TO 25 POUNDS or you will break the the block!!!
Rob

[trbig]

You are correct. In reading the steps above the pictured torques, one was for the timing plate allen screw, and the other was indeed for the front and back nuts on the head.

Tod

[Falken]

Happy New Year to you guys.

Well, over the holidays I got the head off, it came out real easy.

And.....

It had been off before as one PO has taken a dremmel to the intake ports. Head Nuts weren't that tight either. (My 11 yr old son undid them)

So I took out the valves and took the head to a shop.

Latest is that they took off 4 thou.

Getting it back Saturday and will lap in valves.

Gasket set and intake rubbers on order from Georgebits.

One questions, both intake and exhaust valves are double springed, does it matter which way up the springs are fitted?

Cheers
Rob