How to part the cylinder head from the cylinders - stuck gasket - 1980 gs550e

[ukjules]

I think that should be the first advice anyone ever gives on a project !
I forgot it.

Anyway head dismantled and readying to take out and clean the valves etc ready
for transplant into anohter head when I get it.
As the head was knackered i tested a drill with brass wire brush to clean it up.
Works fine.

How do you clean up the bottom of the valves in situ ?
Mine were and are totally crudded up. What do you guys use to chip away at it
when the brass brush on a drill dont do the job ?

 

[Guest]

try the sledgehammer again.

 

[chuck hahn]

Noone ( least I didn't ) say anything about wedging in a screw driver OR OR prying!!! These cause damage to the machined gasket surfaces!!! How does the surface on the upper rim of the cases look now????

 

[ukjules]

The head and cylinder is finished - I have moved on from the madness of parting the head
and now need a head and cylinder. Searching now , some memeber have said they might have them.
I am now expert in how "not" to take a head off, remove gasket ..............

I was just measuring my pistons and bore to see if the new cylinder might fit my pistons when i get it.
pistons - 55.7
bore - 56.1 - think thats out of spec - was smoking when cold
this from a not brill vernier caliper but near as damnit

i only took it to bits as the base or/and head gasket was leaking and it was smoking when cold.

 

[JTGS850GL]

How on earth I missed the bolts is beyond comprehension.

That's why I posted about the one screw and the remaining bolts. It's happened to others.

 

[ukjules]

Is a 1978 cylinder head the same as a 1980 one ?
I have found one , cheapish , it loks identical to mine and i could transfer
all my bits onto it ?

 

[JTGS850GL]

Is a 1978 cylinder head the same as a 1980 one ?
I have found one , cheapish , it loks identical to mine and i could transfer
all my bits onto it ?

No. At least not in the US. The 77-79 heads used 22mm VM carbs while in 80+ they switch to 32mm CV BS32SS carbs. The boots don't bolt up and the ports are smaller on the earlier VM heads. Not sure in the UK though. Something to check into for sure.

 

[ukjules]

My inlet (on my broken head) is 28mm (inside dia) and exhaust 36mm (inside dia)
I asked the chap and he said his was the same exactly.

I reckon it is the same head (date wrong from chap) ! I am going for it

 

[Crank]

Thoroughly enjoying this thread. Made my evening

 

[ukjules]

It is an absurd thread but I will get this going again and soon.
I have gone from hitting the engine (gone barking mad) with a sledge hammer to get it off - then releasing some bolts
where it came off - oddly with ease to now rebuilding the top end.

I think I have a cylinder head - inlet and outlet the same as mine so how can it not be?
If it is not I will clean up and sell (free sledgehammer included)
Have to poick it up though 100 miles away.

Only need gs550et 1980 cylinders now so let me know if any about ...........

J

 

[Grimly]

Anyway the reason it didnt come off was that I left some boilts
in.
The only rreason for doing this insane , stupid, idiotic thing is doing too much at the samre
time. A lesson learnt !
I got it off withj a sledge hammer in the end ! until I realaised about the bolts.
Clearly I am not doing well today.

That takes some sort of biscuit.
Well done. I think you've won this month's prize for idiocy.

 

[Sandy]

That takes some sort of biscuit.
Well done. I think you've won this month's prize for idiocy.

Don't feel bad, the month is but young. There are people here including myself that have done much dumber shlt than that.

 

[Guest]

I know how you feel Jules. Long long ago I had a Bonneville 750 and the head wouldn't come off. Did all the gentle tap, tap, tapping and used a wooden mallet with bits of wood and nothing moved.

The hammers got bigger and the force increased and still nothing. Then the red mist descended and when I came around I had a cylinder head in my lap. Then I got on the phone and ordered a new one.

NOTE: The cause was the head had deformed around the 2 middle studs and wouldn't pass the wider threaded part of the stud.

I have also destroyed a spoked wheel in similar circumstances.

 

[ukjules]

You are right it was the "red mist" that came onto me.
The mistake is terrible but I wont make that again - i hope.

Anyway - I have found parts !
1 - Head and Cylinder will be arriving before this weekend.
I am now cleanign up the old gasket on base and removing parts from my old cylinder head and
intend to clean up the components. oh and ordering up gaskets.

What is the best way to clan up valves ? (out of the bike)
they are hard coated ? do i use a brass brush or can i use steel on them ?
ideas appreciated

J

 

[tkent02]

Thoroughly enjoying this thread. Made my evening

+1, I was going to suggest throwing on 650 cylinders and head "while you're in there", but after realizing the cases need to be hogged out to do the 650 swap, I'm thinking he probably doesn't have a big enough hammer for that.

 

[ukjules]

Ho ho-
It is almost good this happened as valves now out and they were well crudded up.
Cleaning them now ready for new head.

Question:
Valve seal are well stuck in ! Not that i need the old ones how the hell do i get them out
to replace when they wont come off yanking with pliers ?
The new head is going to be revamped

 

[DimitriT]

You are right it was the "red mist" that came onto me.
The mistake is terrible but I wont make that again - i hope.

Anyway - I have found parts !
1 - Head and Cylinder will be arriving before this weekend.
I am now cleanign up the old gasket on base and removing parts from my old cylinder head and
intend to clean up the components. oh and ordering up gaskets.

What is the best way to clan up valves ? (out of the bike)
they are hard coated ? do i use a brass brush or can i use steel on them ?
ideas appreciated

J

Valves clean up with a brass wire brush wheel.

Note: Your new head should come with came shaft caps. You cannot swap those with other heads. And take care not to mix them up in reassembly.

 

[ukjules]

Head now stripped out.
Valves cleaned and managed to pry out the old valve seals (i have never gone this far down before)
just to see how they fit.
Not so hard at all so far !

Valves were terrible (pic below)

The method i used to clean my valves (the other head is coming with its own) was a
elec drill clamped to bench - valve inserted and very mild sandpaper used to
get crud off.


Question:
Are we saying that you should only use "brass" wire wheel/brush ?
Can you use sandpaper ? Can you use a steel wire brush ?
What is "the" way to do it and not damage them ?
Brass would not have got the stuff off on mine for sure. How my bike even went ?

By the way - my bike smoked when cold and lacked power a bit I think and would not tick over.
Valvle clearances were perfect, Carbs balanced, mixture set and played about with but plugs
1,2,3 were black ..... just some general info as to why I started this.

 

[ukjules]

valve not cleaned up - is this bad - what effect does this have on performance ?

 

[tkent02]

valve not cleaned up - is this bad - what effect does this have on performance ?

No effect whatsoever, this is how valves look after a while. On newer super lean fuel injected heads they stay cleaner, but it doesn't hurt anything. Every old engine from carburetor days had at least some this carbon on the valves, they run just fine.