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Head gasket

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Baz

Baz

Yoda
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Quick question.
Burning a little bit of oil, especially after the car is warmed up after half and hour or so, small puffs of black smoke, distinct smell etc.
90% sure it's coming from the head gasket.
Can I use non-hardening gasket sealant on the head gasket, or is one of those forbidden areas as opposed to water pumps etc?
Thanks.
 
No nothing on head gaskets but CLEAN CLEAN CLEAN. However all head gaskets are not created equal use a good one.
 
Thanks Jack, wanted to be sure, any recommendations on a good one?
I'm seeing these copper ones and all manner of different materials. The engine is stock and I'm not racing it, nor have any high performance mods.
 
"Payen" Moss has them alnong with a cheeper version.

The Payen has special things like copper O rings around the water access holes etc.
 
Oh should have said, check head for level whild it is off the car. Might even think about a valve job along with it.
 
Blown head gasket would be puffing white smoke & you'd smell anti-freeze

Small puffs of black smoke after warmed when you give her power isn't head gasket - its either valve seals or rings....do a compression check both "dry" & "wet" to determine which.
 
There's me thinking it was a $20 fix.
It's going to the shop to get the calipers blasted tomorrow, I'll add that check to the list.
This is going to be expensive isn't it?
 
Might not be, as I said before, pob need to redo valves and level head. crosses fingers.
 
Not necessarily - if its the valve stem seals, it can be done pretty inexpensively...heck, I know a guy who says he can do it without removing the head!
 
Hoho, good trick that. In any case if head is off take it to the machine shop and have it worked over.
 
I'll do all the removing and such, strip it all down and just send the valves over with the head. The potentail for error if I do is too huge.
I think I can hold it off until winter, and remove the whole lot anyway. That'll keep the costs down.
 
Do not disassemble head, leave springs, valves and guides installed. Tell them you want new guides and valves seated along with head checked for level and corrected if necessary, maybe $60 or so but less than $100 in any case.

To add, hardened intake valve seats for the unleaded fuel we use.
 
There's no reason to change MGB seats if they're not pitted or cracked...NEVER....EVER! On an MGB head, they're not separate - they're part of the head itself...to put new seats on a head, the machine shop has to grind the old ones out & press new ones in...around here its about $12 per seat.

As for guides, the only reason to redo them is if the old ones are sloppy! The machine shop can check them for you.

Probably, if it is the valve seals, all you're gonna need is new seals & a good 3-angle valve grind.

But, a compression check - dry & wet - is definitely in order before you do anything!
 
yep, I bad exhaust seats of course.

Those were not things to do necessarly, things to talk to machinest about and check to see if they need doing.
 
Thank you as always Tony.
I'm trying to get a handle on how much of this, if not all I can accomplish myself over the winter with no rush or pressure, with several other minor refurbishments under the hood (excluding 3rd gear synchro and layshaft) I wanted to take advantage of the lump being out.
As the car and I are still getting to know each other, we haven't established a line on "what is normal" in terms of behaviour and performance; by replacing stock with new stock, on most systems I can safely eliminate a possible / potential problem area later. Obviously the engine is always a problem area, specially at this age so whatever I can do that needs doing will be done, and it will live.
Now, it's a matter of principal, I've sunk way more money into this than it's worth and I won't give my darling wife the satisfaction of looking at a 4 wheeled paperweight in the garage saying "I told you so", (besides, the midget is older than her) so I'm going to do this, nut by nut, keeping my promise that I won't take her to the shop. Brake calipers excluded, they needed blasting.
If that means freezing my tail off in the garage all winter getting trenchfoot and dropping washers in the crankcase because my fingers are numb, then so be it.
I've read every thread in the forum even from before I have joined, soaking up all the generous helpings of knowledge into my niave skull knowing that some day it will all come to use, and it has and will continue to; the game's afoot and the beloved MG in my garage will purr happily with the pride that I restored her, him, it and the frail anatomy of a valve will not deny me.
That wasn't intended to be a rant, I'm just excited about getting into the guts of it, and hopefully smelling like roses on the other side.
 
Barry - do you have a compression guage or access to one? Some local auto parts houses might rent one....pull a 'dry' compression check of each cylinder (remove each spark plug 1 at a time & put compression guage to it)...write down those numbers....then, go back & do it again but first squirt some oil down inside the spark plug hole (that's 'wet')...write down those numbers

Then, post both sets of numbers here & we can tell you where your problem lies!

&, yes, pulling the head is pretty straightforward.
 
[ QUOTE ]
yep, I bad exhaust seats of course.



[/ QUOTE ]
Jack, I knew you meant exhaust, I just wanted to clarify things for readers who may not know.
None of my cars have hardened seats in them, and I haven't noticed any significant valve seat recession. I had the head off the '63 about 12,000 miles ago, and everything looked fine. I did a valve job on the '72 about 15,000 miles back, and only had to brush the seats lightly.
Jeff
 
I did not have Miss Agathas done either, but then she is not a daily driver so I figured.... Also figured that head will be replaced with a 12G 285 in the next year or so, that is if I can find one priced right.
 
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