cracked cylinder head - what to do to prevent it again

So like many others, I have cracked cylinder head. the bummer is it was a low km engine (62km), however it gets worked hard towing a covered car trailer quite a bit. And I drive it like a car vs a van when not!

I have to fix it, or sell it, and as I really love the van (our camper) I think fix is the way to go. (I even considered seeing if I could do an engine swap for a D4D but it is too difficult)

So the damage is done, so now i want to prevent it happening again.

My current thoughts are
1. mandrel bent 2.5" exhaust to remove gasses faster and reduce back pressures. heat wrapped
2. less restrictive air filter. also adding a snorkel for colder air
3. decent temp gauges - water temp and exhaust gas temp
4. electric fan to replace the viscous fan with automatic temp controlled one and manual override
5. Custom aluminum higher volume radiators and ducting

I am also looking at doing the ECU at the same time for better engine mapping for towing

Does any one have any other thoughts or ideas. things I had thought about were
A/ mounting a snorkel on the left side and creating a duct to cool rear of engine
B/ looking at how to improve the cooling into the engine radiators with possible additional pulling fans.
C/ conversion to switchable transfer box so can run as 2wd. (need free wheel hubs as well)
D/ change diff ratios???

obviously driving more sedate and not towing are not viable options!!!!
keen to here anyones thoughts.

Michael in New Zealand

A new rad and a good flush will help.

Although an electric fan may help I think that the viscous fan is man enough for the job, providing it is in A1 condition. I towed with mine and drove it like I stole it!

If your pockets are deep go for it.

Did you overheat due to the head cracking or did the head crack due to overheating, former just the head and rad and maybe the thermostat, later maybe all your mods?

Hey Clive

pretty sure cracked due to over heating. I have had the radiators flushed and cleanedand new thermostat and cap. it did not help as damage already done. and they were not that bad.

funny thing is it's only it seemed random for a while. It overheated, then I had a flush done and no issues for a year, although no hill towing and only short tow trips. Then while away on a 8 day camping trip, it overheated three times after hard hill driving (long stints). Had the flush and clean done, and still got the issue.
I am about to use some of the CRC head repair stuff, which everyone is raving about CRC head repair

hopefully this will work as a temp repair until I get the head replaced

http://crcindustries.com/auto/?s=401224-6

Right it is just a temp repair, sometimes works for years sometimes just a few hours.
Before you start, from cold start engine and remove pressure cap, if it foams like an erupting volcano then that if a head crack.
Small bubbles maybe a small crack or an air lock.
No bubbles nothing wrong with head look for leak elsewhere.

Any steam in exhaust on start up, difficulty starting?

Thanks Clive
interesting enough, the issue is only when it is hot.

at cold there is no volcano for sure.
when cold there is minimal if any loss of fluid. I just got back from a 250km trip and did not loose any water. I was very easy on the van; no full throttle, no overtaking; no issues. also very cold external air (not over 10 degrees)

I'm going to take it in for the gas/water test next week and will see what happens then.

I have ordered a snorkel from china due in 10 days.

Hey nzkiwiguy,

How did you go with the snorkel? Did it make any difference? Did you end up solving your overheating issues?

brierly89 wrote:

Hey nzkiwiguy,

How did you go with the snorkel? Did it make any difference? Did you end up solving your overheating issues?

Hey there. Not sure the snorkel is the factor that made the difference but it has not overheated again since I had all the work done.

Probably the most useful think was the exhaust gas temp gauge. It has changed my driving habits a lot. You definitely do not push the accelerator down as much and over fuel the engine.

I still drive it fast and hard but are more aware of accelerator position.

Michael