I suffered, a big overheat problem on my 1600 xflow, and had no option but to drive home
Basicly, the water pump gave up. and i lost cooling, and as i had the half tonneau on the car, couldnt see the temp gauge
my mistake!

We put more water in, but not enough, and i limped home

at one point, the engine got very noisy, knocking and rattly, but i switched off with in 5 secs, and pulled over
the car was left, and cooled down for about 45 mins, and was refilled with water, to the top, and i drove home,

on the way home the car was overheating on the gauge, and blowing blue/white smoke from the exhaust, but no NASTY noises, but down on power,

The engine did get VERY VERY hot

The engine is now out, and in bits, the head appears to be ok, and is straight, the headgasket is well buggerd!
the block appears to be ok, and again not warperd (top and bottom)

So, EXPERTS, is the engine ok for a rebuild?
what damage could i of done, that may reveal itself later ?

I plan on a rebuild, even if its only a spare engine, as i have souced another engine fairly local, for my main engine

Regards

Steve

my water pump went on my Vecta. Lost all the water & went off the temp scale. Fitted a new pump and was fine. If the head is ok check the core plugs are ok. You should be fine.

Always a risk cooking an engine, did it myself recently, filled with water and drive to the barn
In your case unless the head has warped your ok
Check bearings, all of them, check block deck is flat and head is flat

Over heating can cause the piston rings to lose tension due to detempering what is in effect ba spring, it can also cause the oil film on the cylinder bores to break down causing metal to metal contact between the pistons/rings and bores. Big end, main bearings ,cam , followers, rockers etc can also be affected. As to what damage yours has suffered ? Sometimes if you are lucky you can get away with just a head gasket and thermostat change , another time you may need a replacement engine

The biggest potential problem are the piston rings, even if the pistons show no sign of damage if the rings got really badly over heated you may find a few months down the line you end up with ring not sealing.

Good chance of bearing and crank damage as well as possible piston damage if the ring grooves has
become soft and deformed. Seen a few where that has happened, rings get stuck in the grooves and results
in a smokey engine that is down on compression. Knocking and rattly is never a good sign.

I'd strip the whole lot for a full inspection..

Thanks guys,

Engine is stripped, and appears to be ok, and is all square, checked at m8's machine shop.
He can lightly skim all surfaces to recheck, if required

main question, is
even if all "appears to be ok, and straight" can there still be damage done to the block/head ??
as i dont want to waste a rebuild on a shagged engine block/head

Steve

Don't worry too much about warping on a cast iron head.

The exhaust valves will have had a tough time though, if you want to test the valve sealing prop the head on its side (exhaust ports to the top), fill the ports with kerosene and look for leaks. If no visible leaks on the combustion chamber side direct a jet of compressed air round the periphery of each valve and look for micro bubbles in the port.

Thanks BT, i will try that,

Regards

Steve

Im all out of kerosen,! is diesel ok

Steve

First engine I ever built, brings back memorys reading this thread, 711m block, push rod motor, all cast so should be fine with head skim. Any photos

Did mine with DESO fine, petrol works aswell

Valve stems can get pinched in their guides when the head is overheated, so valves (exhaust and inlet) might have contacted the pistons and bent slightly. You'd need new valves and probably guides in that case. It depends how hot the head became and how snug fitting your valve stems were in the guides. Also check for cracks in the head between valves.
Guess how I know.

I would have thought the loud knocking noise when head gasket went and you were limping home would be the hydraulic effect of the water getting into the combustion chamber, as it cant be compressed like the fuel and air vapour. I could be wrong, but can’t ever imagine the extra heat causing the valves to hit the pistons. I would lap all valve’s back in anyway if your doing rebuild. Bore it out to 1700 new pistons and jobs good.

quote:

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Originally posted by unijacko67
I could be wrong, but can’t ever imagine the extra heat causing the valves to hit the pistons.

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I get what you mean now sorry, as the guides must have nipped and held valve open even though the rocker/tappet wasn't pressing against it, so nipped tighter than the valve spring could even cope with.