Technical Cooked engine

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Technical Cooked engine

Rado77

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Hi guys,

because a lot of issues with my car I created separate thread for this topic. Is better to handle all issues/solutions here rather than solve partial issues in many threads.

Overal picture: car Punto 2013 1.4 8V bought with unknown history, 60.000km. Found wry exhaust manifold + burned oil & oil sludge in camshaft area. New oil, spark plugs, flap cleaned, valve clearances checked, compression checked. Car is starting perfect, running well, but main issues were (and still are): high ticking from camshaft area when engine reach operational temperature. By frequency of ticking its camshaft related, not crankshaft (but some piston can meet some valve, thats possible). Another issue is engine noise during acceleration or constant speed. No errors in ECU, MOT passed 2 months ago.

Today guys (who is watching me and my issues) I fond another 2 issues, which are more than strange! 1, I hear ticking also on supercold engine (at morning) directly after start the car. Once engine is heating a little bit, ticking disappear (and its back once engine reach operatiobal temperature). 2, I felt on hand on cold engine that air is blowing from intake (box with air filter), but from connection of piece of flex plastic tube (throug which is air sucked) and big air filter box!!! It means that pressure going from head is bigger than vacuum pressure created by pistons! And that means that some of exhaust valves doesnt seats properly and leak air from cylinder during compression or something like that. As you probably remember, I was surprised that when I unscrewed oil cap, I felt big pressure on my hand. And regarding compression test - when we measured it, we didint have compression tester with proper thread, so we used only extension with rubber end which we pressed down by hand during measurement. And compression reached 12 bar on 2nd and 3rd cylinder, but then it dropped to 5 or 6. We thought that its because of that rubber extension of barometer...but on ctlinders 1 and 4 we successfuly measured 12 bar without drop.
Plus I know that someone before did head repair because I saw that exhaust valve on 3rd valve was shiny like new oposite to other 3 ex valves.

So what now? Leave whole thing as it is? How is possible that starts are always perfect and car is running good?
Very very strange, specialy why I feel air going from airbox out instead of sucking air in? Of course when I remove whole filterbox, flap will suck my hand inside :) But also color of spark plugs is ok, all the same like white coffe and as I said, car passed emission control 2 months ago...
 
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I can remove pressure in head by disconnecting hose (which is clean inside), extend it with another piece of hose and mount it somewhere under car + blind hole on intake for that hose...It doesnt solve whole situation but I'll be sure that pressure inside head isnt so big.
Very strange! And engine doesnt consume oil, I checked it today, level still the same after few months, no smoke from exhaust

So whats your opinion here? What to do if car is running, passed tests? Leave it as it is and thats all? I'm afraid of doing general repair because somebody has to grind head surface for example...and grinding it again...it could be too much! Yes and new timing belt, tensioner, water pump, new coolant of course, coolant level still the same
Plus another problem with fixing that exhaust manifold surface, as I mentioned maniverter was wry (on 2nd and 3rd cylinder output) so I grinded it to make it flat. After mounting it back engine was quiet and I was happy. But after few days engine was noisy again, so I re- tightened all maniverter nuts. Few days of silence, but then noise again...so Im fighting also with this issue (temporarily solved by radio volume on 10 or more)

So as Bernie said, someone fixed car "somehow" for selling it away...and it fortunately passed MOT :) But again - starts are perfect, accekeration good, comparing to my Renault Fluence 1.6 16V 110hp almost the same acceleration power
 
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And maybe that ticking is caused by one of valves which doesnt close properly, and compressed air from cylinder goes between valve stem and valve guide and fire shim up which hits camshaft lobe, and thats that ticking noise...too much crazy? Maybe during previous repair they only replaced that ex valve on 3rd cylinder but doesnt checked if it seals properly in seat, and thats causing all issues....

I think I sholud start with pressure test again, dry and wet, or just let pressurize each cylinder through spark plug hole with piston in TDC.
As I understand, if piston is in TDC (completely up), both valves are closed. So if there's leak through intake valve, I'll hear and feel it through flap. If through exhaust, I should feel abd hear it from exhaust. And if its going through piston rings, I shold feel it through dipstick pipe
 
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Update - looks like false alarm regarding air from airbox. Once engine heated up a little I felt that its sucking air inside ok. So it looks that on cold eng has valves smaller dianeter and doesnt seal properly in valve guides, but once get hot they increase it's diameter and seal ok.
Thats very good finding for me! I'll check it tomorrow also on hot engine
 
Ok, so on hot its sucking air ok through aibox. So back to original plan - diag, reset, re-learn and triple engine flush , then fixing ex man leak. I'll update you with news
 
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Ok, so on hot its sucking air ok through aibox. So back to original plan - diag, reset, re-learn and triple engine flush , then fixing ex man leak. I'll update you with news

You are over thinking. You need to make an adjustment to the following:

You want perfection. you have almost no tools. You have almost no money. The car is not so important. The car is running acceptably fine.
 
You are absolutely right! :) I want perfection (what is impossible overal, especialy on car with overheated engine) :)
My biggest problem in my head is that engine was quiet and now isn't quiet. And I MUST SOLVE IT !!! :) You know, we need this car every day to drive over city (mainly to work and back) and I want it next 5 years. That's why I'm taking care of it

Anyway I thought about cylinder head ventilation - and it's really good idea to remove that hose from filter box, because in current setup, oily hot air is going to flap and that's completely useless + engine love cold air, not hot air. So it's better to blind hole on filterbox, extend hose from cylinder head and mount it somewhere under car (far enough from air intake to cabin)
 
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You are absolutely right! :) So it's better to blind hole on filterbox, extend hose from cylinder head and mount it somewhere under car (far enough from air intake to cabin)

This is called illegal emission ...
 
Ok, that with that hose...we can forget on it :) Not important and working thing ;-) More important for me is now finding that the same ticking as on hot idle I noticed alsoon cold engine. It depends also on temperature. So it looks like lubrication related instead of heat related (changing valve size or something similar). I will see after those engine flushes. It recommended also authorised FIAT service, and another independent service too when they saw that mass in cylinder head and noticed that ticking on hot
 
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1. Now it's "everything related".
Heat, temperature (inside and ambient), lubrication, load (idle or driving), VVT, valves (whole "valve train", all parts/elements), exhaust (leaky or not), intake, PCV system ("breather"), "evap" system, and the seized (possibly) piston rings (single most important part of the internal combustion engine) if engine was "cooked". Maybe that's why you have too much initial blow-by when cold.
Plus possible head deformation/distortion after overheating (it's a 3D object, so skimming one surface only - for head gasket - will not straighten the whole thing out magically).

You can try the piston rings freeing, un-seize. Needed or not (Preventive Maintenance). Squirt (with syringe) some oil+kerosene or oil+flush (or straight flush or diesel fuel) into the cylinders (via sparkplug holes) and leave for a night. Probably shot of WD-40 would "work" too.
Waiting/soaking period (for hours) is necessary, to minimize the catalytic converter polluting/poisoning.

2. Manual cleaning (inside the head, after removing the camshaft, and tappets) should be done many many months ago (by "mechanics" who discovered the black goo - while doing timing belt job and/or valve lash/clearances, if I remember right from your other topics), now doing excessive flushing (2-3 times in a row, one session) is risky (make one flush at the time and wait till next oil change) and will never remove all deposits, sludge.

3. Have you checked the vacuum readings with real "analog" gage/gauge?
https://www.google.com/search?q=engine+vacuum+testing Easiest diagnostic test ever.
Stick it into the small breather hose, below (under) the throttle body. Vacuum-meters are cheap.
Maybe it will tell, detect something (needle shaking or so) while ticking sound pops out and goes away.

4. For sure, there is some "damage" in the engine. Goal is to find out what/where "it" is and how serious (and if it can be ignored - probably "YES", if symptoms are stable and car is performing well, passes inspections, etc.).
 
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Perfect reply (as usual)! Thank you very much! Ok, so only one flush per year (oil change). Good, this saves also some money.

Regarding putting that oil+kerosene or diesel into cylinders - how much do I have to add to each cylinder please? And do I have to add spark plugs back, or leave it "opened" during night?

Regarding changing shape of whole cylinder head during heating - strange is that when I tightened again ex man nuts, 2 days it was completely silent. So maybe some stud broke at 3rd day...I dont know yet what happened and there's cold outside...I'll wait with this few months and then I'll check it properly, measure, skim if needed + change gasket because now there is thin metal gasket (that type of 2 divided gaskets - one for cyl1&2 and one for 3&4. But original gasket is thick and in one piece)

And thank you very much for info about that vacuum tester! So helpful!
 
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A. Yes, one gentle flush every oil change (which should be around 10000 to 12000, maybe 15000 km).
No "long-life" bullsh*t (20-30 k). But too frequent oil change is also bad, harmful for the engine.
Oil works the best after first 1000-2000 km or so. Same is very true for all filters in the car. Primitive mechanism - brand new paper must be partially, initially "loaded" (clogged pores) to start filtering better (passing smaller particles). Downside is resistance to flow increasing with time.

B. Amount is not critical, just pour some (5-50 ml per cylinder will do the job - or do nothing, we will see).
Spark-plugs, doesn't (probably) matter much, where you put them. In a safe place (so gypsies can't steal them).

C. Fiat used wrong (bad design) manifold studs, cheapest possible style. There's no way to hold them while doing/undoing the nuts, so stud will turn too (and pull/rip the aluminium threads). There should be hex (internal/external) or torx on the studs. And there are studs like that on the market.
Proper_Studs.jpg
 
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A, yes, thats just my case - 10.000km per year
B, and do I have insert spark plugs back after adding to cyls, or leave it opened without spark plugs over night? I saw video when guy didnt gave back spark plugs. At morning he used big rag, cloged holes for spark plugs with it, and cranked engine few times. Then he mounted spark plugs and done. Is it correct procedure please?
C, yes, these studs are "naked" :-(
 
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Some small update - so after cleaning valve cover (specialy inside the part which cannot be removed = metal plate through which is oil distributed = bad access) is situation like this:
when engine is cold, and I remove oil cap, it's sucking oil cap back - so there's small vacuum inside head. That's probably ok, but definately this is something new :) And when engine is hot, there's not so big pressure in head than before. Also oil isn't splashing (I mean only oil drops) through oil cap hole than before, so oil distribution changed somehow after cleaning of head cover. This is better condition than before I think.
-> Only few days and I'll order Liqui Molly 300ml engine flush + new oil.
 
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Small update - crazy, crazy, crazy! :) So engine is living it's own life :) I checked situation with pressure/vacuum, and I can confirm my previous post:
- when engine is cold, I feel on hand that air is coming through filterbox out from main breather pipe. And oil cap is little bit sucking to it's position - when I unscrew it, I feel that valve cover is sucking it back a little bit - CAN ANYONE GUYS CONFIRM THIS PLEASE ON YOUR CAR ???
- when engine is hot, everything is OK, I feel that air is sucking in through main breather hose and theres small pressure under oil cap = OK
But definately after cleaning valve cover , the pressure in cylinder head is not so big than before, I can tell it's 75% weaker than before, also now oil isn't splashing out through oil cap hole than before.

And 2nd thing - regaridng engine noise - few days it was strong noise, mainly during acceleration, but last 2-3 days it's quieter. I remember that noise was similar than engine noise with unplugged VVT valve. So after that cleaning process there was some small issue in VVT system like sludge moved from one place to another, or some air was inside VVT puley...I don't know.
Plus of course I still hear exhaust manifold leak (I can also feel it by hand - confirmed the same leak than before from 2nd cylinder), but overal engine noise is much quieter than few days ago :) So something "moved/cleaned" inside VVT system I think.

-> So that was small update, WF new oil ordering & flush (I already have 2 new oil filters Valeo), looks that's really related to oil sludge/cleaning whole engine
 
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Small update - oil flush done. I cannot decide if ticking is gone because now here is max 5 degrees of celsius, but everytime when I checked engine after longer trip, there was no ticking.
So 2 minor issues remains - exhaust manifold leak (only small), will be repaired during spring
- found dusty oil drops on oil pan - looks that's only from drain plug - I have that type without gasket and I felt when I tightened it back that it's thread is damaged a little bit. I cleaned bootom of pan with rag and will check. After putting new oil there and trip home, there was no leak through drain plug. Will check later...no drops over nigh on asphalt, so OK for now. Here I can just buy new plug, or maybe replace whole oil pan (which was also rusty) when I dismantle exhaust manifold during spring (March - April)
 
Update - engine flush done. Nothing changed at all. Yes, outgoing oil was black so Liqui Molly worked, but looks that it was only "cosmetic cleaning". Whole exhaust is getting worse, ex man leak is hearable during acceleration and constant speed, during deceleration I hear rear muffler's bass sound, there is some hole again (previously fixed temporarily with Bosal paste). I have to wait few months for better weather to fix it completely
 
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Just update after few months - so engine ticking is gone completely without any intervention! I dont know what happened but one day I didnt hear ticking on hot idle. I started to check it periodicaly, and its 2-3 months without ticking. And car was on idle sometimes 2 hours, sometimes more. So looks its really gone! :) And as mentioned before, there are few exhaust leaks - will replace whole exhaust this year. I'm very happy overal, engine is running well :)
 
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