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MG Midget and Sprite Technical - head gasket replace

I have a '77 mg with a suspected bad head gasket. She blew up on highway going 60mph, oil poured and no restart. On cranking she sounded ... funny. Oil was observed together with antifreeze running down manifold side of the engine starting from where I think the head gasket is. Last night I got everything off, but the head itself. Rockers and pushrods looked fine, but now the head is pretty well stuck,just wobbles a tiny bit.

I read the suggestion here about feeding a bit of rope into the spark plug hole to help... but then what? Crank the engine, or what?

Also, while trying to remove the manifold, I attemped to remove two bolts that were facing up on the manifold, rather than the rest of the manifold bolts which faced out towards the right wheel. These promptly broke off and on futher inspection seem to be holding the manifold itself together (intake to outtake maybe). Can I put the manifold back on or do I now need a new one?

Thanks!

drGian
GD Di Loreto

forgot to mention it's a midget, 1977. Here is a pic of the busted nut.


GD Di Loreto

Hi -

As for the broken studs you mentioned, those bolt the intake manifold to the exhaust manifold, as suspected. With the intake being aluminum and the exhaust being iron, there's been some electrolysis which has corroded the nuts in place. I wouldn't worry overmuch about them. If I remember correctly, the design of the exhaust manifold will permit drilling through and just using a bold and nut in each location. Sorry if that's not accurate, but I'm not near my car at the moment.

As for your engine failure, I sincerely hope it's nothing more severe than a blown gasket. This engine has been known to fail due to worn crankshaft thrust bearings... Have you inspected the sides of the block to look for holes or cracks?

Best of luck,

-:G:-
Gryf Ketcherside

Thanks for the response. It looks like I could drill and replace, but it also looks like they will hold. If not, I will know right away and I could drill and replace after things get put back together.

The immediate concern is (hopefully) the head gasket. I don't see any other issues on the outside of the engine, no holes in the block or visible cracks. Also, the rods were all tight againt the rockers which rules out any cam issues I would assume. But if I can get the head off I should see what the issue was.

So the question is, how to do that? I've removed the 10 bolts, as well as the carb, manifold, and water pump, nothing holding it on. It rocks, but it is stuck. My next step will be to turn the engine over, but I'm interested in this rope down the spark plug hole trick. Can someone explain that to me?

drGian
GD Di Loreto

"interested in this rope down the spark plug hole trick. Can someone explain that to me?"


feed rope into the cylinders through the spark plug hole and then rotate the engine so that the piston pushes the head up and off for you (put the transmission in gear and rock it on the wheels is the most gentle way, rotating the engine by the starter is a bit risky because of the amount of impact into the piston is hard to control)


Norm
Norm Kerr

great, I will do the rope trick and post the results. I can roll the car, there is room in the garage and it weighs about 90 lbs so no need for the starter and the risk.

One last question, one cylinder/rope or more? I would think 1 would do it.

GD Di Loreto

good news is that rope trick worked great, got her off nice and easy. Bad news is the head gasket was just fine. Piston #3 was moving freely and covered with oil and as I got my head down in there I noticed a nice hole that I suppose the broken piston rod punched through the side of the block (pic attached).

So we have a dianosis, the question is do I

a) try to fix this
b) swap the engine
c) throw the Midget away

the car is in pretty good shape otherwise, body is clean and inside is nice. Trans is good too. I have a space for her and the time and energy so let's rule out c) for now.

I think given the hole in the engine now I have to replace the entire engine. Engines on ebay look like they are going for $700.00 USD.

Advice please? Or is this now a new thread?

drGian


GD Di Loreto

You can find used 1500 engines for $100. Then rebuild it and you'll have a strong running car that you can trust.
Trevor Jessie

perfect, where do I look for the used 1500 engine? Local junkyards, or internet?
GD Di Loreto

Ouch. That's what I was afraid of. :-(

Ditto what Trevor said. I've never actually had to buy an engine (and never hope to...) but this forum is a great place to start.

Hoping you're back on the road soon - and trust me, Midgets are worth the trouble -

-:G:-
Gryf Ketcherside

Post messages over on the MGexperience.net both in the trader section and in the midget section. Also post a message on the britishcarforum.com in the spridget section. Area craiglist is also good.

You may have to buy a whole car and part it out. The rear differential and front disc brakes usually bring in a couple of hundred. You can usually get another 100-200 out of other bits and bobs (depending how long you want to try and sell the stuff). You would want to hold onto the rear axles for spares... and maybe a few other items.

Parting out a car is a good experience to familiarize yourself with the how it all goes together.
Trevor Jessie

As Trevor says: Via Craigslist:

I have purchased both a complete car in great shape, $400. and a .010" overbore rebuilt 1500, never started, $250.

Sorry to hear about your block... "On cranking she sounded ... funny."
RJ Reeves

Read to bottom of this thread
http://www.britishcarforum.com/bcforum/ubbthreads.php/topics/725401/1098_engine_core_need_it#Post725401
Trevor Jessie

This thread was discussed between 22/11/2010 and 25/11/2010

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