Some folks have cleaned their radiators with a high pressure cleaner, and for I've decided to keep my Tahoe and get it back on the road, I think I should clean the radiators and coolers to improve cooling for the towing that is to come. I've got a high pressure cleaner, but I wonder how exactly I should do the cleaning.

As far as I get it, I should take the grille and the fan shroud off and spray the water from back to front through the radiator and also try cleaning the gaps between the radiator and the other coolers. But I'm afraid the water will spray back all over the engine and eventually damage the fins of the radiator. Once I pulled the grille and found the gaps between the radiator and the coolers being quite small and probably hard to spray.

So, what's the best way to do it? Is some chemical cleaning solvent helpful or can I do as well without?

Is it a good idea to put a 'fly-door lattice' ('Fliegengitter' --- I can't find a translation) in front of the coolers to keep the bugs out in the future, or will it reduce the airflow too much?

Hi Lee,

I have found that the procedure you mention works just fine. I usually use a nozzle on the end of a garden hose. I have not tried to use a high pressure washer. It is true that you can bend the aluminum fins if you are not careful. Start with lower pressure and methods, and go up from there.

One thing that I KNOW works very well is to take the entire radiator OFF, and then take it to a radiator repair shop. They will 'rod' the core (after de-soldering the caps) and clean the entire assembly. It will be clean for sure.

Sincerely,

Rob :)

Thanks, starting with low pressure is a good idea :) What about the gaps between the radiator and the coolers? Do you take the coolers off or loosen them? They can be loosend from the mounting brackets, but the lines going to them don't exactly allow them to be moved aside.

Taking it off would be overdoing it, I think :)

If it's like mine, take the top of the fan shroud off, and wash downward. I don't have a front a/c condenser coil to contend with, so I can't relate.

Is it a good idea to put a 'fly-door lattice' ('Fliegengitter' --- I can't find a translation) in front of the coolers to keep the bugs out in the future, or will it reduce the airflow too much?
Lee,
Fliegengitter = Bug Screen (more or less), although in this context screen alone would suffice. In English, there are many types of screens, you just need to describe them according to the application.

Over here, you see many people with Fliegengitter on the front of their grills in the southern states. The south of the US can be very hot and humid most of the year and the bugs are prolific (and sometimes huge!). In the northern states you see much less of this (cooler and drier). My experience traveling in Germany tends to make me think that the reduction in airflow would be greater than the benefit of adding an extra screen. That said, I saw a bunch of Dodges at the drags this weekend in Pennsyvania and they all ran extra screens at the front of their stacks - none of the GMs that were there had extra screens.

I agree with the other posters that a high pressure powerwash should be your last resort - those fins are not hard to fold over.

OT - there was a guy in one of the Dmax forums looking for German members, you might want to look him up?

Take Care

'Bug screen' sounds good, thanks :)

Your right, we don't have too many bugs, and they are not that large. But besides bugs, the front end catches all the dirt whirled up by cars in front over the years, and much of it probably clogs the coolers. I've seen temps rising to 90 degrees C while stuck in stop and go traffic on a hot day with the AC on, until I turned the AC off and the cabin heater on to keep it lower when it seemed wanting to go up further.

Last resort? Hmmm, I'll have to see what I can do --- the coolers in front of the radiator seem to keep the dirt mostly out of it and seem to need the cleaning the most. I should go for the cooling upgrade, but there's no chance doing it before my holiday starts.

I'd have to spend $$ on it: Downpipe, cooling upgrade, trans cooler, but parts are difficult to come by.

Use a air condition coil cleaner. Its a strong alkaline cleaner that will foam up and lifts dirt bugs etc. I have used aerosol and like the liquid better.

After you take grill off brush off any crusty bugs straigten fins if you can. Its tedious but take your time and be careful. Then spray the liquid coil cleaner, let it foam up, and it will push trash/bugs out. Rinse and repeat as necessary working top to bottom. Spray coil cleaner from front and back and from sides as good as you can. Its pretty harsh stuff so maybe not a good idea on a windy day ie avoid overspray on any paint.

OT - there was a guy in one of the Dmax forums looking for German members, you might want to look him up?


Who was it? IŽve been searching the Dmax forums, but to no avail.

Use a air condition coil cleaner.

Ah, so thereŽs something designed for such cleaning :) Hm, I think IŽll just spray the coolers from the front and try to get at the gaps from the sides. The frontmost coolers donŽt have the thin fins, afair.

IŽll let you know how it turns out.