Intercooler failures

[whereisgibson]

Theoretical question time.

1) I've read if you add any type of intercooler to a 1hdft one gets a modest performance increase eg +15hp, even if you don't tune the pump in any way. Like when the truck is cold it goes a bit quicker and is a bit crisper, it stays like that instead of a bit sluggish when up to temp.

2) If you did tune the pump to make use of the intercooler, you'd be adding more fuel.

3) The debate around w2a vs a2a seems to come down to a2a being passive and unlikely to fail, but w2a being a better solution but relies on pumps and secondary cooling etc.


So my thought is if you don't tune the pump, and any fitted intercooler failed, the engine would just run fine anyway (1). So that makes the a2a simplicity argument (3) a bit redundant because failure isn't a problem.

If you did tune the pump (2) for more fuel by just rotating the pin (the boost wouldn't change so no need to mess with the spring tension etc), and then the intercooler failed, then you're just going to be running a bit sootier, which would take 5 mins to fix if you could be bothered to, but I would think the fuelling change to maximise a modest increase of only +15hp would not cause much variation in egts nor plumes of coal.

This leads me to conclude that one either has no intercooler, or w2a. And if w2a, a fiddle with the pump is optional.

Is my thought process valid? A failed intercooler basically causes no serious issue especially on a manual fuel pump system. So a2a is beat by w2a in all useful measures: space, consistent performance, less length of pipe.

Or is this the whisky playing tricks.

Thanks!

 

[AndycruiserguyLomas]

Hi Martin,
As I see it I don't know how an intercooler can fail, fail to pass air through it? fail to cool the air?
An W2A as you call it is more efficient but relies on water being pumped. If the water isn't pumped the air still passes through.

My only experience of intercooling an 80 was on my first 80 which was about 4 years old at the time ( 1HDT) It was fitted by Allard and I tweaked the pump a bit so it just didn't smoke and it did go well. After a hot run on the motorway I felt the pipe to the inlet manifold and it was stone cold, so it was working.

All in all it was worth doing just for the little extra " push" when the throttle is applied.

 

[Lorin]

I’d suggest reading through this thread, especially the first 20-30 pages or so https://forum.ih8mud.com/threads/the-official-1hdt-intercooler-thread.514067/

There is extensive data testing a2a, w2a, and top vs front mount. All data converges on front mount a2a being the optimal set-up by a considerable margin. That isn’t to say there aren’t pros for all set-ups just that overall a2a front mount offers the best performance in most situations. Both a2a options are also considerably simpler with less failure points than w2a.

 

[whereisgibson]

Well this is the part that didn't make sense to me either about failure points.

As I see it I don't know how an intercooler can fail, fail to pass air through it? fail to cool the air?

And if it did, worst case is that the truck would breathe as it were designed to.

All data converges on front mount a2a being the optimal set-up by a considerable margin.

Thanks I'll have another read. Such a rabbit hole

 

[Lorin]

And if it did, worst case is that the truck would breathe as it were designed to.

Not quite. The air in the intercooler has already been pressurised (i.e. compressed) by the turbo. This is why it gets hot and why an intercooler helps by cooling the pressurised air. If you get a leak it is a boost leak and you lose power. Your engine needs pressurised air, not air at atmospheric pressure.

 

[Grimbo]

Lorin hit the nail on the head.... if a front mount A2A fails you will loose boost and power from the leak ...it will black smoke on acceleration....and lack power
But that is all it will do..... any water 2 air has the possibility of dumping coolant straight into the inlet manifold and hydraulic locking the engine.... =death to your engine .
Few if any of the current high horsepower AG and plant engines I work on use anything other than a front mount air 2 air intercooler.... they are operating in many cases in exactly the same scenario as you would be doing hard high horsepower work at slow speed in sand off road. Often some claim water 2 air will be better in this type of scenario as at low speeds your are relying on the engine driven fan only for cooling air through the front mount intercooler with no ram air affect . With water/air the cooling is not dependent on fwds speed.
Personally I would always go front mount air 2 air and if worried about air flow at very low speeds just fit a switchable kenlowe fan on the intercooler..... not that it would ever be needed in 99.8 % of Landcruiser use..... the reliability and lack of ability to stuff your engine if they do fail more than makes up for the 0.2% of the time when it may not be perfect