Essex V6 overheating

[JP.]

Have an Essex 3.0 with suddenly overheating issues.

Running triple 40’s and have a tad rich A/F round 12-13.

Heater bypass is not as usual on the back of the triple intake but fitted up front as a standard intake has.

Engine has done aprox 3800 mile after full rebuild without issues. Its been dyno’d & jetted to.

Ignition is a modifiet Aldon points type Bosch without vacuum unit to triple carbs spec hooked on a MSD6AL unit.

Standard compression ratio 9:1.

No true PCV system, just two valve covers to one catch can which ventilates to the atmosphere.

.

Had a points gap issue about 800 miles ago ( to narrow ) so I reset gap to spec but without checking timing. It appeared a bit out of spec with 20’ static timing.

.

Car ran fine without pinging or whatsoever, just as smooth as normal the last 800 miles ( in two days, mostly at 80mph cruising).

.

Just suddenly an overheating engine at 80mph gulping all the coolant out of the expansion tank on the highway.

.

Did had a traffic delay 70 miles before. When I was in, gauges looked oke with electric fan coming in normal to cool and oil temp was about 80’C.

.

While the overheating issue started it appeared that the fan switch was shot so no fan working anymore. Fan normayl doesn't come in during cruising speeds.

It might be that during the heavy traffic delay I missed my gauges later on by focussing on the traffic so it might be that my issues started there by a suddenly shot fan switch.

.

With the overheating, after refilling the engine with water & bypassing the temp switch with the fan full working at all times did not lower my temp but still keeps it overheating with lots of big bubbles coming from the top radiator hose.

.

Working my way around it looking for a problem.

Ignition was a bit out, but it’s a recurved less advance unit and I had no pinging or what soever I’d personally rule that out. I had to notice that during the last 800 miles.

A/F ratio was deffo not lean with 12-13 average.(Innovate LC1 wideband monitor)

Valve clearance was good also and carbs still synchronised. It still runned fine although its overheating.

Some of the outer cylinder head bolts ( original reused) where about 10nm out of range ( stretched???).

Bolts where torque’d during build up with a yearly calibrated Stahlwile torque wrench & checked now with the same tool.

Water pump is ok.

.

Did not re torque heads after 1000 miles run as some internetsites mention. Haynes book does not mention.

.

Heads are of now but I cant see any signs nor damage on the head gaskets (Victor Reins).

No white signs on pistons, valves or combustion chamber ( just black coal on all).

.

Can head gasket issues not always been seen??? Heads might be slightly warped now at about 0.1mm roughly measured. Bring the heads to a machine shop tomorrow for check up.

.

Are there issues with some Essex engine’s that might be my problem now after 3800 problem free miles????

[Col-ashtonmobile]

Firstly , when it was overheating was everything hot ? hoses , radiator top & bottom , is the thermostat ok ?, have the heads been previously skimmed ? , was the inlet manifold bought new or off another engine , let me know and i,ll try and help

[JP.]

Firstly , when it was overheating was everything hot ? hoses , radiator top & bottom , is the thermostat ok ?, have the heads been previously skimmed ? , was the inlet manifold bought new or off another engine , let me know and i,ll try and help

Engine was top& bottom hot on a 400mile trip from CFS. Thermostat was fully open. Intake brand new, slighly skimmed heads, both on engine for 3800 miles.

All the hoses maked burping sounds with expanding them at the same time.

AA did some checks and diagnosed headgaket. I suspected that one too.

Now engine is open and I can't find evidence of that.......

[w p e]

blocked rad or w/pump inpeller spinning on shaft when warm?

[Col-ashtonmobile]

was the radiator hot at the top and bottom ?

[JP.]

Been to the engine shop yesterday.

Both heads where 0.09mm warped so both are skimmed again.

They investigated the headgaskeds and found some heatspots on the firerings telling my heads Have been slightly lifted at some point during my journy.

Could be caused by my dead fan switch ( me not noticing it) + to much pre ignition + slightly stretched head bolts ( as they found 10nm pretty much..)They also sayed that the cooland flow of an Essex engine is not as effective so they advesed me to run the heater bypass on the back of the tripple carb manifold to create a more parallel heat up of the engine.

So its posible a chain reaction of things.

.

ARP head stuts are on their way now.

Engine shop also advised me to retorque any engine after the first 1000km run.

[Ken B]

You should also be using your fan switch to activate a relay to run leccy fans. They're not designed to take the current draw of a leccy fan directly. Stops all this burning out nonsense.

[JP.]

You should also be using your fan switch to activate a relay to run leccy fans. They're not designed to take the current draw of a leccy fan directly. Stops all this burning out nonsense.

Is it???

It is switched by a 50Amps relais as the Spall draws 30Amps peak on startup.

So this isn't the issue. Its hotwired to as a manual override. But I dind't notice my heating problem so I didn't use the manual override mode.

Fan switch is negative connected so no real current draw here.

Just got unlucky with the bastard as it was only 3800km old....

.

Think Ill want a temp activated idiot light also this time...