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SaxMan's Cylinder Head Overhaul / Head Gasket Replacement Thread

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SaxMan

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After determining on the "Today's Conundrum" thread that most likely have a blown head gasket along with some valvetrain issues, I decided to start a separate thread, complete with pics as I try to undertake this repair. Part of the reason I bought an LBC was that I wanted to tinker with it. I did not expect to have to do something this complex so quickly! I briefly mulled taking it to a shop, but I have decided to go the DIY route. If nothing else, it's going to be a pretty interesting learning experience!

Hood removed from the car.

DSC_0006 by onyxsax, on Flickr

I also removed the front grille as I have to replace the hood release cable.

DSC_0010 by onyxsax, on Flickr

This appears to be a vacuum line coming of the forward carburetor. Can someone tell me where the other end hooks up? The line "appeared from nowhere". I believe there is a similar plug on the rear carb. Does it connect there?

DSC_0016 by onyxsax, on Flickr

Spark plugs removed, valve cover removed. Can someone tell me what the yellow plug was once hooked up to? Is it something I should re-plumb?

DSC_0017 by onyxsax, on Flickr

Close up of the mysterious yellow plug:

DSC_0020 by onyxsax, on Flickr
 
More....

The carbs have been successfully removed from the motor. I'll clean them up and give them both a once over now that they are out of the car.

DSC_0028 by onyxsax, on Flickr

The reverse side of the heat shield. A little bit of degreaser should clean that right up.

DSC_0029 by onyxsax, on Flickr

Lots of oil from the cylinder head down, especially towards the front of the engine:

DSC_0032 by onyxsax, on Flickr

One of the things I planned on doing this winter was to replace the exhaust. I'm a bit concerned with the flange between the manifold and exhaust pipe. It was one bolt going through the rear, but the other two appear to be studs? Is this a correct setup. My fear is these pieces were welded together. Then I'd have to replace the manifold as well

DSC_0035 by onyxsax, on Flickr
 
Don't forget to drain the coolant.

And

I've got a nice, spare 1275 exhaust manifold. $35 delivered, if you want it.
 
Before you go very far you will need a good repair manual. I always liked Bentley manual's but you will have to buy them on E-bay since I don't believe they are available anymore. Anyway they are usually cheaper on E-bay. Moss and Victoria British catalogs help in how things go together as well. Recommend keeping the bits that are all related together and labeled in zip lock bags before the pile of parts and where they come from overwhelm you.

Kurt
 
I have the British Leyland manual, which sometimes is so vague in their instructions, you'd almost think they were doing it deliberately. I also have the Bristow book "Restoring Sprites & Midgets" which tends to be a bit more details. Between the two I get a somewhat less foggy picture of what needs to be done. Already have the masking tape and the ziplock baggies...that's something I've already learned from working on bicycles.

Draining the coolant is next. That is something I'm not really looking forward to as the last time I tried it to replace the thermostat, it got pretty messy. I disconnected the lower radiator hose to drain and it didn't work out so well. I believe there is a drain **** at the bottom of the radiator that may be a bit more accessible than I previously thought.
 
Remember to keep things like pushrods and other items in proper order. Before you pull anything apart it all needs to go in an organized spot.
 
I usually just siphon coolant out of the radiator. Slower, but neater.
 
With the caveat that I'm not close to actually knowing much about these things, I'll jump in. It appears you may have once had a pcv valve on the intake manifold and it it now missing. The yellow plug blanks where it would have sat (though the original pcv fitting would have been straight, not bent at a 90). The pcv would have connected to the breather on the timing cover. If the car is a later version, there would have been a Y pipe from the front breather to each of the carbs replacing the pcv. The large amount of oil on the heat shield suggests something may be amiss with the crankcase ventilation. What is the can breather on the timing cover connected to? EDIT: I think I see the Y pipes in one of the pictures, and you have removed it in a later one.

A vacuum line from the distributor runs to one of the carbs. That should be easily seen.

Jim
 
The carbs do have the "Y" connector, which attaches to a canister at the front of the engine. I'm not sure where it goes after it hits the canister. Maybe this fitting came off an earlier 1275? There's an awful lot that could have happened with this car in 45 years.

The vacuum line did break, so I guess I'm going to have to order another one.
 
The yellow plug plugs something to do with the smog pump system. I think that I would want to carry a spare but there is nothing wrong with the arrangement.
 
I hate to say this but since you said you might link to tinker, might I suggest you pull the engine and really give yourself some room to work and have better visibility, this is not a very complicated task, take lots of pictures along the way. You can rent a hoist for a day for $50, I built a little wooden stand on wheels when I did mine. You may be able to pick up an engine stand at HF for cheap, I have seen people on the site turn these into rotisseries for body projects.
 
I finished up the all the prep work to pull the cylinder head this evening.

Intake manifold removed and exhaust manifold loosened up (yes, I took of the last of those bolts). The outer ones came off like regular bolts, while the inner one the entire studs came out, except for one. Is this typical? There wasn't much of the manifold gasket left.

DSC_1001 by onyxsax, on Flickr

Intake manifold on the workbench. Note the difference between the left and right sides

DSC_1006 by onyxsax, on Flickr

My great invention of the evening. I took Trevor's idea of using a siphon to empty the antifreeze and added power to it. I put a siphon tube on an old shop vac. It worked like a champ. I didn't get a drop of antifreeze on the garage floor. I wasn't going to reuse the coolant, so I wasn't overly concerned that it might get contaminated.

DSC_1008 by onyxsax, on Flickr

Heater valve disconnected:

DSC_1011 by onyxsax, on Flickr

Thermostat disconnected. Two were held in by bolts and the third was an entire stud. I also loosened up the little hose that goes from the water pump to the head

DSC_1012 by onyxsax, on Flickr

Close up of the #1 Cylinder valves. Were the valves painted this way from the factory, or was this someone's idea of "customization"?

DSC_1018 Cyl 1 by onyxsax, on Flickr
 
With everything disconnected, it was time to undo the cylinder head bolts and take the head out. The problem was, after all the bolts were taken out, the head is not budging in the slightest. I gave it a couple of whacks with a rubber mallet in an attempt to loosen it up to no avail. I thought about hitting the studs with PB Blaster and/or trying to wedge something between the cylinder head and block, but I figured discretion was the better part of valor and figured I'd check in here before I did something that would end up being a very expensive mistake.

Here is the head with the head bolts and rocker arms removed. Notice how with some of the bolt holes, only the nuts came off and the studs remained, while with others, the entire stud came out. Is that by design or is there another reason behind it?

DSC_1026 by onyxsax, on Flickr

This is the head bolt in the center of the block. It looks like it may have become cold welded to the head. I think this is my obstacle to getting the head off:

DSC_1027 by onyxsax, on Flickr

Some of the head bolts before I put them in a ziplock baggie. Notice how the longest one is very heavily oil soaked, while the others look more typical

DSC_1021 by onyxsax, on Flickr

Rocker arm assembly on the workbench. It looks to be in relatively decent shape.

DSC_1024 by onyxsax, on Flickr

Any suggestions on how to remove a stubborn cylinder head would be greatly appreciated!
 
SaxMan said:
Any suggestions on how to remove a stubborn cylinder head would be greatly appreciated!
Click to expand...

Put the spark plugs back in and spin the motor on the starter. If that doesn't work, take some rope and feed as much as you can into the spark plug holes on #1 and #4 cylinders. Turn the motor over by hand.
 
HealeyRick said:
Put the spark plugs back in and spin the motor on the starter. If that doesn't work, take some rope and feed as much as you can into the spark plug holes on #1 and #4 cylinders. Turn the motor over by hand.
Click to expand...

Do I need to put the rockers back on?
 
No feeding the rope into the cylinder will allow the rope to compress and push the head up from below as the piston raises up. Must be done by hand do not crank with the starter motor.
 
And by hand meaning with a wrench turning the big nut on the crank. You won't gave one that big in your toolbox. Might be 1 5/8". Someone will correct me if I'm wrong. Tractor Supply < $10.
 
Did you disconnect the little bypass hose b/t the head and the water pump? You'll never get it to budge if you didn't.
 
AN5Sprite said:
Did you disconnect the little bypass hose b/t the head and the water pump? You'll never get it to budge if you didn't.
Click to expand...

I didn't completely disconnect the hose, but I opened up the hose clamp

Will the pushing the car in 4th gear work with the rope trick?
 
whack the head a few times with a dead blow hammer
 
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