coolant bypass to td42 head

[uzdnabuzd]

has anyone got any photos of this complete on their truck??

Also who does this mod and how much

Thanks

[coxy321]

Most of the performance workshops i've heard of do it. DieselTec, PGS, JPC, Big-O 4x4.

[DanielS]

I have some pictures around here of how I did my head. If I can find them I will show ya.

[garth]

is this the same set up thats used on the 4.8 petrols? how does it work and where do the bits come from?

will be keen on installing it if it merits engine life........

[sim70n]

I have some pictures around here of how I did my head. If I can find them I will show ya.

How did ya go with the pics

[SLASH]

x2. Whats a coolant bypass and how does it work? Cheers Loz.

[BOOSTED GQ]

JPC do them for about $600 may be a bit more thats all the work and the coolant rail and parts. Its a drilling into the head near the glow plug that helps even and better cooling around the pre-cups and is recomended on big power TD42s. If you want to see what thay look like check out JPCs web site thay have a picture of one on there some where.

[garth]

gudday

heres a shot of the JPC unit. I guess the head has to come off and be machined?

Does anyone have a better shot/ made there own? looks pretty simple...



regards garth

[BOOSTED GQ]

thay do it with the head on thats why its so cheap.

[awill4x4]

I'm surprised that JPC drill into the water jacket on the inlet side when everyone else drills them on the hottest side (exhaust).
The pic below is one of Ontracks turbo petrol cars but it shows it on the hottest side of the head which is where you would expect any steam pockets to occur.
All Head services drill theirs in the same place as well. (it may even be and All Head services kit in this pic)
Regards Andrew.

[TUFFMQ]

I'm surprised that JPC drill into the water jacket on the inlet side when everyone else drills them on the hottest side (exhaust).
The pic below is one of Ontracks turbo petrol cars but it shows it on the hottest side of the head which is where you would expect any steam pockets to occur.
All Head services drill theirs in the same place as well. (it may even be and All Head services kit in this pic)
Regards Andrew.

on a td42 u cant drill on the exhaust side and im pretty shore the combustion camber in the head ant the whole size of the head its only 1 side witch is the drivers side where jpc drill's into

[BOOSTED GQ]

Thay are drilled in the inlet side because thats where the injector is, and it sprays the fuel into the pre combustion chamber and thats the problem. The huge amount of heat in the pre-cups. So the idea is to get the best cooling around the pre-cups ins nit somuch for the heads cooling hense why thay are on the inlet side.

[sim70n]

there good piks cheers tuffmq

[DanielS]

hey boys,

sorry for the late reply, yeah mine is like the ones pictured. I removed the head and flush it though, was worried about metal scrap getting into the radiator.

Anyway, as previosly mentioned Diesels have an issue in head desin here and the is amplifed once you start pushing them for Big HP. the issue is that (remove the rear core plug and have a look and feel) there is a huge area that will not flow coolant around the preco chamber and as a result will build a big air pocket once it gets hot. The bypass removes this air pocket giving better cooling.

Daniels

[sw1]

thats a neat looking job

[coxy321]

thats a neat looking job

Given the hieght of that rail, i'm assuming there's a bleeding point on it, as it would be higher than the radiator fill point. Is that a bleed point up near the back between the hoses for cylinder 5 and 6?

[bogged]

thats a neat looking job

Given the hieght of that rail, i'm assuming there's a bleeding point on it, as it would be higher than the radiator fill point. Is that a bleed point up near the back between the hoses for cylinder 5 and 6?

almost looks like one where that bit of light is up the back 1/3

[coxy321]

thats a neat looking job

Given the hieght of that rail, i'm assuming there's a bleeding point on it, as it would be higher than the radiator fill point. Is that a bleed point up near the back between the hoses for cylinder 5 and 6?

almost looks like one where that bit of light is up the back 1/3

Thats the one.

[MONTY76]

sorry to be a smart ass but at the back it looks like a cable tie

[nastytroll]

I'll ask a stupid question.

What difference does it make if you have air on the return from the head to radiator? It is outside of the heat transfer zone, it will not stop the flow of water as the pump will still bubble water through it, and I thought the principla was to get the steam out of the head.

My understanding is; water will get pumped through the block, then through the head, the air/steam will rise through the "blead" manifold and the result will be water flow around the precomp chambers. Water will still drain back through the hoses into the radiator for cooling.

In my experiance, more often then not there is some air in the top rad hose anyway. as it only drains back to the rad it should make no difference. This will not stop the pump as it draws water from the bottom of the rad, the steam will rise from the head to the highest point (bleader manifold), and dump to rad completeing the circuit.

[coxy321]

The less air in the coolant system, the better. Easy as that.