Engine Carbon Cleaning

[Blitz]

Any one got any thoughts on having an engine carbon cleaned. Ie using hydrogen through the air intake. A few mobile companies now doing this but are their any practical problems on a classic engines. Will our cars implode 

Grant

[AndyTV8]

Ed China is a supporter, used it on a few occasions on wheeler dealers 

[Colin Lindsay]

We used to pour Redex directly into the carbs, the cloud of white smoke from the exhaust was amazing but it cleaned everything!

[JohnD]

Hydrogen?!?  Oooooeer, missus!  Dat's powerful stuff, Mr.

 

So what else?   Americans swear by (no, they don't. Americans don't swear, by golly, by gosh!) "SeaFoam" some commercial goop.

 

But there may be a simpler cleaning agent - Water.  Yes, water.

Here's an American who gets some very convincing poo out of the tail pipe:

And  Briton who gets all technical on the case - endoscoping the pistons - ReeSpect!

John

[Blitz]

Mmm if it’s good enough for Ed.....

company say they can do classics and carbs just wanted some reassurance there arnt any risks. Thought I’d ask the experts on here 

[DerekS]

There was some stuff on the go in the 70's called PDR, Petroleum Deposit Remover, can't remember who the manufacturer was; it was sprayed directly into the carbs... It must have had some effect because you had to tweak the mixture afterwards. Whether it worked it not, who knows, but the effect at the back end of the car was like a chimney fire, really upset the neighbours!

[Anglefire]

There is something called terraclean being offered in some places for diesels in particular and apart from the people doing it, no one has a good word to say about it. Some going as far as to say it does damage to the engine. 

Not saying this is the same, but personally I wouldn’t do it. 

[Pete Lewis]

First question is why do you think you need it ???

Pete

[hugh]

The clearances in the older engines are much greater than modern ones if you do this you could well end up with a greatly increased oil consumption, like a couple of people I know, I'd stay away

[Unkel Kunkel]

Echoing Pete’s comment -

Is there a need   for ” De-carbonising ” or “decoking” ?

I haven’t  even heard the terms for years .

The Saturday afternoon ritual whipping the top off engines to   scrape the head and the piston tops (trying  to leave  a rim of carbon around the edge in an attempt to mantain a seal, of course) I thought had   disappeared with   such things as side-valve sit-up and beg Ford Prefects.

The only “ decarbonising”  I have had to in recent times is clean the thick carbon sludge from a seized EGR valve - on a  thoroughly modern diesel.

[JohnD]

There's is way of cleaning out carbon deposits 

 

 

Not sure its that effective - the inside still looks pretty coked afterwards, but by Jiminy it looks fun!

 

John

[Nick Jones]

On 19/04/2018 at 9:11 AM, hugh said:

The clearances in the older engines are much greater than modern ones if you do this you could well end up with a greatly increased oil consumption, like a couple of people I know, I'd stay away

This.......  If your engine is significantly coked up it's because it's an oil burner.  And the carbon deposits are probably helping to keep the oil-habit in check.  Burn/dissolve them away and..... you may well regret it.  Guess how I know that......

Nick

Cleaning out inlet manifolds and EGR passages on semi-modern diesels is a whole different game - and actually useful.

[Colin Lindsay]

+1 to Nick's post. Sometimes cleaning our engines, particularly if they're high mileage, can do more harm than good. 

It's different with moderns; I removed the EGR on my TD5 with no ill effects whatsoever, apparrently doing so improves power and leads to a cleaner running engine. 

[Anglefire]

The modern Diesel engines do have egr valves that certainly on the older engines are worth removing and blanking as they serve no useful purpose except in the lab. They just force feed your engine with crap. 

[Nick Jones]

The purpose of EGR is to lower the combustion temperature and thus reduce NOx formation.  Unfortunately this also spoils the combustion efficiency so you'll end up burning more fuel and producing more CO2 and particulates.

My very aged A6 TDI is known has the family name "Soot Monster" for it's (now "cured") tendency to lay down a massive fog bank behind if given a big bootful of throttle after pottering along behind a tractor for a couple of miles.  Since the EGR valve err, broke, it doesn't do that any more and also does another 5 miles or so to every gallon.  It also goes through emissions test on the first attempt rather than needing all the tries allowed.

Nick