Pressure in coolant KAD 42

Head bolts can be used again, although the setting are something like 60 nm the 90 degrees twice( don't quote me on the 60mn bit it was a guess as I'm stood here.

The fact is the bolts will stretch but are not the design which most modern engines have whereby they stretch to achieve the ability to hold torque and once used are scrap.

There is a measurement in the manual stating overall length, but they can be used again.

All bolts are designed to stretch to some degree. This is how they create a clamping load, and can be used several times if they are torqued within their elastic limits. If over torqued, they go plastic, and will not retain the right clamping load. It is this risk that makes service manuals recommend new bolts. That is why torquing to the correct figure is critical.
 
Hi,
not sure if this is ongoing or has been solved.
just wanted to say I had similar problems with a KAD42A (made around 1992).
in my case the engine dumped all its cooling water in the bilge a few hours after a complete professional rebuild. The engineering firm were very good and rectified the matter at no cost to me and with no fuss- as right tbhey should have done after a £10k+ rebuild.
the issue turned out to be a problem with the head gasket that had not fitted properly after the rebuild. They rectified this and the issue went away.
what was interesting was that the issue did not occur while pottering around at 2,000 revs or less for the first few hours - it only happened when I used power and planed for the first time. So problems like this don't always show themselves at low revs or when the engine is not under higher loading.

I have also been told that the expansion tanks on the KAD42A are renowned for being too small and iff you fill them more than half with coolant/water, then they can over-pressurise and spill coolant out. So be sure that it's not juts a case of your coolant level being too high. I have that once too - coolant in the bilge but no engine overheat - simply becausze I filled the expansion tank more than half.

hope this may be of some help.
 
Since this is one of the top posts of the search term "KAD32 Pressure in coolant"

I can testify that if your KAD32 pushes out coolant it is almost guaranteed the head gasket. I also had exhaust gasses so it was quickly identified with exhaust gas indicator fluid.




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Just a short comment on coolant. It is important that you check your coolant level WHEN HOT. The coolant should never exceed the MAX mark when at operating temp or it will push out coolant to the bilge. It means once engine is cold the coolant level should be close to LOW mark.
 
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