Cracking Blocks

Hi all, I have a 4.0 SE Rangie, two weeks ago she overheated on a wet and cold day,I stopped and let it cool and limped home keeping an eye on the gauge. i did the nose test on the warer res tank and could smell fumes.
I have stripped the top end off of the engine and found no significant holes in the head gaskets but found the water pump is flapping around so this could be the root of the problem.
On inspecting the bores I cannot fing anytrace of cracking anywhere.
Does anyone have any experience the same or know where the liners crack when they do.
Thanks

The only over heating i had was the fault of the bearing, on the belt tensioner, it had seized, check that with your hand and try turning it

Check your thermostat, that its not in the closed position and isn't sticking

hello mate , if a liner slips ( the liners dont crack , its the block that cracks ) you would not be able to see it , as movement of 0.5 m/m is enough to cause overheating problems , in some cases depending what position the engine stops in the liner can appear to be in its original position , the only accurate way to detect the problem is once the heads are removed make up blacking plates to cover the water galleries and pressurise the block this will the show up any leakage up the side of the liner .
as for your water pump that may well be your problem , it should certainly not be "flapping around " on the bright side it a damn lot less expensive to replace than the block .
rick.

markp38 said:

Hi all, I have a 4.0 SE Rangie, two weeks ago she overheated on a wet and cold day,I stopped and let it cool and limped home keeping an eye on the gauge. i did the nose test on the water res tank and could smell fumes.
I have stripped the top end off of the engine and found no significant holes in the head gaskets

Click to expand...

You wouldn't necessarily see a hole. It could be just discoloration on the metal faces. Have you checked your heads for trueness? That is not hard. You will need a straight edge and a feeler gauge

markp38 said:

but found the water pump is flapping around so this could be the root of the problem.

Click to expand...

That is certainly a BIG cause for heating..but doesn't account for the smell of exhaust fumes in your coolant reservoir. BTW, how was the water pump loose. Was one of the long bolts out?

markp38 said:

On inspecting the bores I cannot fing any trace of cracking anywhere. Does anyone have any experience the same or know where the liners crack when they do. Thanks

Click to expand...

Liners don't crack so that you can easily see it. They get loose and do so for a number of reasons. One of the most common is a cracked block. You will not normally see the crack with the liner in. Here's why. These are images of your block cut in half (and another showing a comparison of a pre-Coscast block and the new Coscast block). If the crack is where the arrow is pointing (illustrating what was happened with the aging molds and the coolant passages, you will not see it.





You cannot be sure that there is anything amiss with the block as yet. More tests to do.

Thanks Guys
I will pressurise the block to see if I can smoke it out