This is a little similar to what I was talking about in previous post, less reference to the cam chain issue which is tension-ed by oil pressure and the carbon buildup on the inlet valves. PSA/Mini 1.6 THP - Problems in the intake camshaft timing system
The dreaded carbon build up on the intake valves...
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If you've ever had the head off a car that has been running for sometime with a blown head gasket you'll notice how clean the piston/combustion chamber and valves are on the affected cylinder. the water entering the cylinder seems to clean the internals.
Would water injection help?
Would water injection help?
No. This crud isn't in the combustion space. It sits on top of the hot valves on the manifold side, and restricts incoming air flow. The only guaranteed removal methods once it forms are scraping or blasting.
Interested to know if anyone has had the walnut blasting done and where ?
Was regularly using Seafoam at changes which definitely made a difference early but now at the point of little to no benefit and either need to find a walnut blasting service or have a mechanic do it manually taking the head off.
Tried Advan who do a lot of blasting but they don't have the inlet manifold adapter for the THP - they had used universal adapters on some cars but said it was less effective, time-consuming and messy so would prefer not to do it that way again.
Was regularly using Seafoam at changes which definitely made a difference early but now at the point of little to no benefit and either need to find a walnut blasting service or have a mechanic do it manually taking the head off.
Tried Advan who do a lot of blasting but they don't have the inlet manifold adapter for the THP - they had used universal adapters on some cars but said it was less effective, time-consuming and messy so would prefer not to do it that way again.
It isn't a job I'd want to do with the amount of windscreen overhang on my car, but a mechanic tells me that if the inlet manifold/plenum is removed, with a mirror he can scrape clean the valves to a sufficient standard without touching the head. I suspect it's an all day job, even with practice, so costly.
Many years ago I cleaned the heavy build up on the back of the inlet valves on my series 2 405. I removed the injectors, and cut down the sides of a toothbrush and used this with Subaru inlet tract cleaner to scrub the back of the valves clean through the injector holes. the motor blew some smoke on start up but went on to be healthy for another 100 000 Klms until I sold it.
Diesels never had port injection that sprayed fuel over the valves.
And diesels do suffer from deposits from the egr systems... thats the reason for all the blanking plate kits.
Called them and was quoted $995 and told it was a min 3 week backlog
I have a little to say on this. Over the years I was challenged with the prince engine and oil burning and low power etc.etc.etc.
It is a very poorly made engine in many ways in my opinion. Apart from the hopelessness of the timing chain assembly and the chain tensioner, which is oil pressure fed only and does not have a one way ratchet to keep adjustment on the chain when starting.
Hint number 1. ( ratchet deleted to save cost)
Hint no. 2( we had the same style tensioner on the old skool days. Toyota, MB, etc.)
Hint number 3, a loose bicycle chain can jump teeth when the tension is slack.
I have seen engine dripping down valve stems several hours after removing the exhaust to change the blocked Cat. Blocked from? Carbon. Burnt oil deposits.
Coking of the valve in the inlet once happened when engines ran cooler and the inlet valve would cool the fuel which would leave deposits. Think about engine oil dripping onto the inlet valve head. Carbon build up might occur? Oil can the go into the cylinder this way too. Oil explodes and we know have a prince engine with a pinging fault.
Not to mention the piston ring sealing. Blowby past the rings after a ping event bought on by oil in the chamber. That quickly destroys the ring and we have worse oil problems.
They are fixable and work fine when everything is in good order. My thoughts are,
Carbon build up in the inlet, on the exhaust valves, blocked mufflers and Cats. Engine pinging oil burning, smoke. Vacuum lines failing on turbo engines from, you guessed it, oil damage. Low boost , blow-by, oil in the charge cooler, inlet manifold etc.etc. comes from a poorly sealing engine internally.
1/ valve stem sealing
2/piston ring sealing.
Are the most obvious items .
Engine management is another. Poor wiring loom manufacture but the most common is the earthing of the engine management controller and the actuators and sensors. Only found using an oscilloscope often the main earth on the left hand inner guard hidden behind the enclosed battery is faulty.
Lagging throttle response is often the electronic throttle not responding due to earth potentials at the ECU's main earth points.
I'm old and out of the game now and I've probably missed other details the highly trained know about, yet may not be able to publicly share.
Well! I'm glad that's off my chest and the above is only my humble opinion. I admit to not using a capital P for prince as I feel the engine doesn't require that kind of acknowledgement. The 3 cyl Peugeot have I hear is quite the opposite of the last engine.
Ref: Puretech Motor Peugeot - https://www.youtube.com/watch?v=1RSVaL
This EB2 engine has a wet belt cam shafts drive with cam-phasers on each cam? I believe the Ecoboost also has this wet belt technology. Does this make changing the belt more difficult or is the life of the belt extended for a much longer period maybe Life of Type? I also noticed the EB2 is a very new design, maybe it does not vent oil mist on the inlet valves (PSA should have learned by now!) and may not suffer the direct injection issues as Subaru, VAG, Prince etc related to modified older designs like the EP6 series, 4 cylinders engines which were a proven Peugeot design updated with a BMW patent head and cam chain system with direct injection to meet EURO6 standards.
This EB2 engine has a wet belt cam shafts drive with cam-phasers on each cam? I believe the Ecoboost also has this wet belt technology. Does this make changing the belt more difficult or is the life of the belt extended for a much longer period maybe Life of Type? I also noticed the EB2 is a very new design, maybe it does not vent oil mist on the inlet valves (PSA should have learned by now!) and may not suffer the direct injection issues as Subaru, VAG, Prince etc related to modified older designs like the EP6 series, 4 cylinders engines which were a proven Peugeot design updated with a BMW patent head and cam chain system with direct injection to meet EURO6 standards.
Puretech Motor Peugeot
https://www.youtube.com/watch?v=1RSVaL-905g
https://www.youtube.com/watch?v=1RSVaL-905g
I think I find this one more amusing:
[video=youtube;NHZrApVekXE]https://www.youtube.com/watch?feature=player_detailpage&v=NHZrApVekXE[/video]
[video=youtube;NHZrApVekXE]https://www.youtube.com/watch?feature=player_detailpage&v=NHZrApVekXE[/video]
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Is it Polish? Dons Peugeot (208 number plates!) disassembles your Puretech 1.2 engine before you buy it? But they didn't check for any carbon build up on the inlet valves? I wonder if they can get it back together without the factory support? (P.S. www.Ricardo.com do these tear down engineering reports then sell them to whoever for about $1000. I guess that is how competitors get access to Peugeot IP?)
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There's an engineering overview of the EB2 in a mixture of French and English at https://www.arts-et-metiers.asso.fr/manifestation_cr/840_compte_rendu.pdf
All it has to say about inlet fouling is: Encrassement conduit admission: Réglage distribution. Perhaps someone can explain how timing affects the inlet manifold in a direct injected engine.
All it has to say about inlet fouling is: Encrassement conduit admission: Réglage distribution. Perhaps someone can explain how timing affects the inlet manifold in a direct injected engine.
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Ref: http://www.delphi.com/manufacturers/auto/powertrain/gas
"Inlet duct fouling, Distribution adjustment" I'm not a thermo-dynamics automotive engineer, but the 'Delphi' cam phasers can alter the inlet timing of the camshaft up to 70 degrees crankshaft degrees. This allows late opening of the inlet valve therefore exposing it to the fuel injection spray. It's all controlled by the ECU, anti knock detector, sensors etc as is the direct fuel injection and ignition. (P.S. The PSA report on the PureTech 1.2 is very detailed. Competitors engines at A & B seem to be the VW 1.4FSI 4 cylinder and The Ford Ecoboost 1Lt 3 cylinder. The Ecoboost 1Lt 3 cylinder is very similar architecture with off set crank, combustion shaped piston crown, exhaust manifold cast into the head and variable oil pump etc etc. There is information about wetting of the inlet valve during the combustion process! This is done by one of the direct injection multi (x3) spray patterns when the inlet valve is open, therefore replicating a port injector wetting of the inlet valve.) Looks like a very sorted engine to me. I have driven a 308 Puretech and goes very well. I could feel confident with this engine.)
"Inlet duct fouling, Distribution adjustment" I'm not a thermo-dynamics automotive engineer, but the 'Delphi' cam phasers can alter the inlet timing of the camshaft up to 70 degrees crankshaft degrees. This allows late opening of the inlet valve therefore exposing it to the fuel injection spray. It's all controlled by the ECU, anti knock detector, sensors etc as is the direct fuel injection and ignition. (P.S. The PSA report on the PureTech 1.2 is very detailed. Competitors engines at A & B seem to be the VW 1.4FSI 4 cylinder and The Ford Ecoboost 1Lt 3 cylinder. The Ecoboost 1Lt 3 cylinder is very similar architecture with off set crank, combustion shaped piston crown, exhaust manifold cast into the head and variable oil pump etc etc. There is information about wetting of the inlet valve during the combustion process! This is done by one of the direct injection multi (x3) spray patterns when the inlet valve is open, therefore replicating a port injector wetting of the inlet valve.) Looks like a very sorted engine to me. I have driven a 308 Puretech and goes very well. I could feel confident with this engine.)
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