Head gasket??

[Dookbob]

I have the cylinder head off my M600 in order to remove a broken exhaust stud.
When I come to replace the barrel and head it looks like I would use 3 bond on the base gasket, but because there is no gasket on the cylinder head do I refit this CLEAN, or do I used a suitable jointing compound. Obviously I will need to replace the O rings with new ones.

[utopia]

Neither my genuine ducati manual, nor the haynes, makes any mention of a jointing compound for the heads.

[jerry]

No gasket requred on head on aircooled motors ,

[dunlop0_1]

I lap the barrel and head together with fine valve grinding paste. You do only have limited rotation back and forth due to the exhaust but it does work. :mand:

[manwithredbike]

after some valve work, i simply cleaned all surfaces, used original 'o' rings, left base gasket well alone and bolted down gradually to recommended torque settings. all was well, no leaks etc.

[slob]

No gasket requred on head on aircooled motors ,

EARLY aircooled motors

[Saint aka ML]

Exactly early one's have gasket and assembling without it leads to disassembly soon after ;)

[nuttynick]

I think you mean early motors don't have gaskets?

[jerry]

how early is early I have seen 2004 models with no gaskets so 1990-2004 is a long time

[Saint aka ML]

My 1993 one had a gasket, so did a 1998 m600 we stripped. I think no gasket since first m900 injected.

Thing is I had paired a 2002 ie bottom end with cylinder's and heads from carbed 1993 and it still pissed oil all over without gasket. So stripped it again, added gasket, added thre-bond and no more leaking not even the little annoying oil moisture on all early monsters.

[Dukedesmo]

No head gaskets on my 900 engine which is date stamped '95. Don't really see how one could be fitted as the facing surfaces are very small and interlocking.

The same with a '97 ST2 engine that I bought as a cam donor.

If there is some kind of retrofit gasket kit I would be interested...

[Dookbob]

Thanks for the info , all I have to do now is drill out the broken exhaust stud. It,s going to have to be done freehand, there is no way I can mount the head on my milling machine table with the flange square to the spindle like I was hoping to. I will probably end up with a Helicoil. There is no way I am going to use thread lock when I replace the exhaust flange studs, it's going to be copper slip, I don't want this again.

[utopia]

I was informed by Mr Gremlin a while ago that Nitric acid will dissolve steel but leaves ally untouched.
I haven't tried it myself, but it sounds like the diy version of a spark erosion machine and I will certainly give it a go next time I get a broken stud.
I guess you'd drill most of it out and then apply the acid down the drilled hole.

Also, I found that std stainless dome-head nuts will work on the exhaust studs without the stud bottoming out. I filled mine with copperslip too, but being careful to avoid an hydraulic lock.

[gary tompkins]

Assuming it snapped off flush

Spark eroding is probably the best method of removal

[Dookbob]

Is nitric acid available to buy, and if it is , where would I buy it from. I remember reading on here that it will shift broken steel parts leaving the ally untouched.
I don't mind having to drill it out oversize and Helicoil it, but I find it a bit hit and miss keeping the drill bang on the centre of the broken stud.

[gary tompkins]

It might help to make a drilling jig out of a thick piece of steel plate or flat bar. Drill two holes in it the correct distance apart, then clamp it to the head in the right place using remaining exhaust stud and a lock nut. Use the jig to center drill the stud before opening it out for helicoil tap.

[Saint aka ML]

Dukedesmo it was a brass sorts spacer/seal. If you look at my engine you can actually see two small hoops on each cylinder where you would use those to lift the seal.

My one was there when I opened the top end, seal had part number and date still stamped on it which matched bike production date.

Like this just my one has two extra hops to lift but I guess they were removed in latter design.

http://www.ebay.com/itm/Ducati-Monster-900-City-City-900M-1999-Cylinder-Base-Gasket-/150832124224?hash=item231e4b9140&item=150832124224&pt=UK_Motorcycle_Parts&vxp=mtr

[Martin C]

Is nitric acid available to buy, and if it is , where would I buy it from. I remember reading on here that it will shift broken steel parts leaving the ally untouched.
I don't mind having to drill it out oversize and Helicoil it, but I find it a bit hit and miss keeping the drill bang on the centre of the broken stud.

As you're in Derby area, you could take it to SEP at Kegworth. They very successfully sorted out serious exhaust stud problems on my previous ST4's 916 engine.

[Mark Taylor]

As you're in Derby area, you could take it to SEP at Kegworth. They very successfully sorted out serious exhaust stud problems on my previous ST4's 916 engine.

I had a cyl head stud spark eroded by SEP:thumbsdown:not only did they quote £25 but charge £75:eyepopping: - they helicoiled it ON THE ****!!:fou: fortunately I was able to prise the offending stud into place on the rebuild, I didn't send it back to them because -
a) I don't know what they could do to rectify it - it's been drilled & helicoiled wrong:banghead:
b) I didn't trust them not to f*ck it up even more:nash:
c) I was sick of the bike being off the road (again):hissy:
I was well p*ssed off having used the same firm in the 80's rebuilding my GS1000 crankshaft and being very happy with them back in the day

[Dookbob]

Thanks for that Martin C, I have used SEP for rebores and re sleeving, so I will bear that in mind. I will try Gary's jig method first, thanks for that Gary.
Just read Mark,s post, definitely try Gary,s jig method first.

[Dookbob]

Gary,s jig method was a success, made and fitted the jig, gave the broken stud a touch with a centre dril, then went through it with a 6 mm drill, then an 8mm tap cleaned out the remainder, so didn,t have to Helicoil it.
Thanks once more for the tip Gary.

[slob]

how early is early I have seen 2004 models with no gaskets so 1990-2004 is a long time

1000DS runs head gaskets 2003->

[gary tompkins]

Gary,s jig method was a success, made and fitted the jig, gave the broken stud a touch with a centre dril, then went through it with a 6 mm drill, then an 8mm tap cleaned out the remainder, so didn,t have to Helicoil it.
Thanks once more for the tip Gary.

Good news - glad it worked out for you

May use the same method myself for a broken engine mount bolt on the buell. Need to get the head off the motor first.. but it's too frigging cold in the garage so can wait until next year :grump: