Z1OwnersClub GB

Hi

I have a 1977, Z1000 A1.
Last year one of the spark plugs started to fowl up, and there was an oil leak from the cylinder head gasket.
I stripped the engine down and had the cylinder bores deglazed, fitted new piston rings, new valve seals fitted and the valves reseated.
I was then told that the cylinder head was warped and required skimming. This was done by a specialist engine company.
When the barrels / cylinder head was returned I was told that one of the outer cylinder liners had moved, and that they "tapped" it back into place.
The problem I have is that the engine is now noisey, which it was not previously.
Could this be due to the cylinder liner moving due to the friction of the piston rings?
If it is, what are my options as to repairing the problem ?

Thanks
Dave Watson

Hi Dave, I used to live not far from you in St Madoes.

Difficult to pinpoint a noise without hearing it, even then it is not an exact science. Can you post a video on Youtube and send us the link so we can listen?

Slight concern when you say he "tapped" the liners in. Usual method is to heat the barrels in an oven and they should drop in place, I tend to think this is not the cause though.

Plenty of members in Scotland to lend a hand. Including FER who just lives the other side of the river Tay.

If worst comes to worst and it is the liners spinning, you might need new barrels or maybe get Westwoods to make some oversize liners.

Loose liners are common and usually not a problem and it's very unlikely for a loose fit to be the cause of any noise.
I have had liners that could be pushed out cold by hand that cause no running issues or noise.
Once the head is bolted down the liners cannot move or rotate as the top hat flange of the liner is trapped between the head and barrel.
Even a factory spec press fit liner becomes "loose" under normal running conditions as the engine reaches temperatures that exceed that needed to remove a liner for replacement.
Only if the top flange has fractured and becone detached from the liner could the liner move or drop in the barrel.

zed1015 wrote:Only if the top flange has fractured and becone detached from the liner could the liner move or drop in the barrel.

A friend once had this on a Ducati 860GTS. It had been tuned to within an inch of its life, where both the barrels and heads had been skimmed (that must have made the bevel cam drives fun to resolve!). The barrels had been skimmed that much that the top flange was wafer-thin, thus the inevitable happened and carnage ensued....

zed1015 wrote:Even a factory spec press fit liner becomes "loose" under normal running conditions as the engine reaches temperatures that exceed that needed to remove a liner for replacement.

Yes, stories abound of people baking painted barrels whilst they are sat on the liners who return to find the casting has slid down all 4 liners, it causes panic for them and much mirth amongst their mates.

David Watson wrote:Hi

I have a 1977, Z1000 A1.
Last year one of the spark plugs started to fowl up, and there was an oil leak from the cylinder head gasket.
I stripped the engine down and had the cylinder bores deglazed, fitted new piston rings, new valve seals fitted and the valves reseated.
I was then told that the cylinder head was warped and required skimming. This was done by a specialist engine company.
When the barrels / cylinder head was returned I was told that one of the outer cylinder liners had moved, and that they "tapped" it back into place.
The problem I have is that the engine is now noisey, which it was not previously.
Could this be due to the cylinder liner moving due to the friction of the piston rings?
If it is, what are my options as to repairing the problem ?

Thanks
Dave Watson

Hi Dave, Definately not the liners moving ! they are always quite loose & under normal conditions cannot rotate .Who rebuilt the engine ? ...were they reputable professional mechanic's with Zed specific knowledge ? Did they really know what they were doing ? Were all the liner lower O rings replaced or re-instated correctly ? A lot people recon you don't need em !!!! ......ignorance is bliss !!! truth is - the factory rarely fit something thats not needed ! They are there to ensure CAPILLARY action is prevented ....so as to stop Head gasket oil contamination which ultimately ends up with leaking compression from a soggy head gasket & some times it also shows up as a resultant engine noise from escaping compressed air . Do you know how much was removed from the head ? Did you ask ? Head skimming is to be avoided at all costs mate ...there can be serious side there issues !
You need to be a bit more descriptive about your mechanical noise mate ! What sort of noise is it & when doe's it occur. Where doe's emulate from . Doe's it change with rev's or loading.
It'd be a good idea to do some simple quick checks . I suggest you run through these - Slacken - one at time, then Re-torque your head nuts ....this done in the correct order & check exhaust gaskets are not leaking too. Pop your Cam Box cover off & Check all your Cam cap bolts are snugged down ( only take them to 9lbs / feet each, NO more ...go carefully there ) check their all the Caps are in their correct numbered locations & that they did not get mixed up . Check your all valve shim faces are not scuffed or trenched ...if you can feel anything with your fingernail on the shim face it's not good & are your valve clearances all OK = 4 thou all round. Check & reset your Cam Chain tension too after checking the central top cam idler units 4 bolts are all snugged up & the unit itself... if gripped is secure & it's doe's not wobble from side to side . Try a Higher octane fuel say 95 or more . Check your ignition timing is correct & has not slipped & it is advancing as it should do . Systematically run through those base level checks Dave & check every thing off as you go. After that if theres no luck & it's still the same... I'm afraid it'll likely need to come apart. Good luck Bud , Johny B