THP (1.6L T) Engine Inlet Decoking/Walnut Blasting

thatguy

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Looking for somewhere in Sydney that does this ? Have scoured the various Pug, Mini & Citroen forums without luck.

Any ideas/experience ?
 
Have you tried the spray in the air inlet procedure? There is a special PSA product and it will almost stall the engine when applied. You'd want 2 cans and the help of an assistant. There is, I believe, a Nulon product to do the same job, which would no doubt be readily available at a lower cost. You may need to make this treatment part of the service job or you might be looking at walnut blasting again. Avoid taking the head off if at all possible as setting the timing again is quite a fiddly job.
 
Thanks will contact names on links.

Yes done the Seafoam thing a few times but with 80K on the clock the improvement is minimal now. Time for something a little stronger !
 
Spoke to Advan ... they advertise on the BMW 1 Series forum a lot. They noted they'd never done a mini or Pug THP engine but lots of BMWs. They believe the manifold adapters they have will work but can't quote a price until they try and do it.

Of note the do the 1 Series BMWs for $495 but he noted some Audi's they do are closer to $1K due to the hassle of getting manifolds off and getting to the inlet. Sadly I think the Pug THP will closer to the later than the former in terms of pricing !
 
Meant to add for about the price of getting it done found this kit which can be shipped from the US. Perhaps its wiser to get then offer it for hire to fellow members ?!?!?!
 
I think you'd be underwhelmed by the interest in others following suit. If $500 includes R&R it doesn't sound unreasonable - but $1K - it would be worth knocking up a kit for a few evenings of flogging away. Surely a good stew in methylene chloride or similar would reduce the blast time/effort required, too?
 
Subaru do one too for the turbo motors. I used to use it with my wrx and sti's
 
Have you done the PCV Delete mod yet?

No but will get to that over the holidays - being so quick and simple. Couldn't get to Advan due to family things but will also get that fixed when I get some downtime.
 
I remember vaguely when I was an apprentice [mid '50's] the mechanic carried out an "oxy decoke". Mostly on old Fords. Chevs. Chryslers etc.
Plugs removed. A kero soaked cotton waste flame was held near the plug hole. An oxygen nozzle was applied to this.
Somehow it loosened the carbon in the cylinders and combustion chamber. I think all this was finally blown out with a start up ?

The excess carbon build up back then was probably caused by low octane fuel and compressions.

Do any of you old heads out there recall this?

In later times one particular Volvo suffered from a really excessive build up of carbon around the valves, under the heads. This reduced seriously the efficiency of the gas flow.
This required removing the inlet manifold and painful scraping away of the carbon with a scriber or such.
One of the upper cylinder products were prescribed to later keep the valves etc clean.
 
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The excess carbon build up back then was probably caused by low octane fuel and compressions.

Do any of you old heads out there recall this?

I never saw it done, but one technique explained to me was,

Remove spark plug, bring piston to TDC,

Use oxy torch to heat small area of carbon on top of piston to red heat.

Turn of acetylene and play pure oxygen onto red carbon.

The carbon would magically disappear.

Possibly a technique to be only used on engines with cast iron pistons.

I recall using this technique to decarbon something or other, and it did work.

Terry
apprentice mechanic 1964-1968
 
I never saw that oxy biz, sounds hairy. Aluminium pistons were in then.

We used to take the heads off and decoke properly. Very often. I have never done it on a modern post 1980 car, so the valve lifters, piston ring pliers and compressors, glaze busters, valve suction caps, etc, etc, have migrated to the very bottom of my least used toolbox. I think some 40 years old valve paste and blue is down there too. Good.
 
I'm surprised someone hasn't mentioned the Carbon Clean System.

A number of manufacturers make the products.

They concept is a carbon cleaning agent and solvent which is circulated through the combustion sections and injectors of an engine.

This done by disconnection of a feed (and returns ?) to the EFI and connecting an external pump system. The engine is the cranked over and the carbon cleaner solvent allegedly removes all the crud off the inlet tract, valves, piston crowns and is expelled from the exhaust.

I believe a high pressure "lance" can also be introduced through the plug holes.

For $150 odd (a few years ago) it may be a viable alternative to major disassembling of the engine.

I have had high mileage engines carbon cleaned. The results have been worthwhile.
 
The procedure the OP mentioned is not for cleaning injectors or pistons, but the inlet side of the valves due to heavy clogging - a "feature" of direct injection petrol engines with not so well-designed PCV systems.

No fuel gets there, so nothing is washed off the valves.

I don't believe the spray into the inlet works particularly well - even though it still seems to be a factory procedure for both Citroën and Peugeot. Perhaps it works ok on "young" engines that don't have much build up.

I never got around to doing it on the 207, though it was probably in need of it at the end.

Here's a link for reference.

I don't think that blocking the PCV system with plastic caps is a very good solution either.
 
I don't think that blocking the PCV system with plastic caps is a very good solution either.

Interested in your thoughts about why not ?

PSA has done this on the newer gen THP200 engines in the likes of the 208GTI without other changes which would suggest they see it either as an improvement or addressing an identified issue ? They sell the parts kit to do it also.
 
Interested in your thoughts about why not ?

PSA has done this on the newer gen THP200 engines in the likes of the 208GTI without other changes which would suggest they see it either as an improvement or addressing an identified issue ? They sell the parts kit to do it also.
I've read many a report of leaking plastic cam covers following blanking of the pipes, along with some potential super knock/missfiring issues. It was covered pretty well on 207oc.com, but unfortunately, that forum had a meltdown recently and changed to 207OC.net and has very little useful info any more.

From memory it causes excessive crankcase pressure issues and lots of white smoke.

The PCV system is basically in the plastic cylinder head cover and has been revised quite extensively from the original version, AFAIK.

An oil catch can system would probably be a better option.

P.S. I've since found a similar discussion on the cam cover here.
 
So this thread is a few years old now and surely people have clocked up some k's on their beloved 208 GTI's. Any solid workshops that offer walnut blasting for our engine?

Advan was mentioned in this thread. I've also stumbled upon Hills Eurohaus which does walnut blasting, but not sure if they've done (or willing to take on) it on the THP200.

Has anyone from this forum taken their's to get it done in Sydney? If so, where and how much did it set you back?
 
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