All mechanics have a read and see what you think

[Robh18]

My trophy has gone in for its major service. It went to a garage rather than Renault them selves due to it costing nearly 500 pounds more at Renault. My trophy was having everything changed that was on the Renault major service check list and genuine Renault parts however i had a small leak of oil coming from the rocker cover sealant, which i was getting done as well. It went in on Monday afternoon and this afternoon had a call from the mechanic working on the car saying he has found oil on top of the piston heads and oil in the inlet manifold. He explained saying that oil could be leaking past the piston rings ??
Firstly i don't know how oil could be present on top of the piston heads as the oil would have combusted and i cant see how from the cylinder it could enter the inlet manifold !! But when i handed the car into the garage i had a small puddle of oil sitting just below the rocker cover (from where it was leaking) and laying at the base of the outside of the inlet manifold or injector rail I'm not sure :? . To take the rocker cover off you have to remove the inlet manifold first and i personally think when the inlet manifold was removed first the puddle of oil has run down into the cylinder and onto the top of the piston heads and also run back a little into the inlet manifold itself. I'm just guessing here, I have had the car for about a year now and regularly check the oil and i have not lost a drop so therefore cant be burning it or it passing the piston rings ??? Someone please help

 

[Robh18]

Just found a pic going to post it in a sec to illustrate where the oil was sitting.

 

[Gazza]

I think your right and most likely it has run onto the piston but I would assume you could tell from how this oil looked. Did you suggest your explanation when you spoke to them?

I had the same oil leak fixed on my T under warranty, took them 2 tries to stop it leaking as the putty they use is very easy to have gaps in.

Hopefully someone with more knowledge on this will pop by soon.

 

[Robh18]

in the pic i have circled in red where the oil had accumulated on mine. It was only leaking from one point on the rocker cover and oil was only present where the two red circles in the picture are. If the mechanic took the inlet manifold off without realizing about this oil then is it possible for the oil to run down straight onto the top of the piston head or past the valves onto the head ?? If so this would explain the oil on the piston heads and also the oil found in the inlet manifold if some of the oil ran back into the manifold when he took it off. ????
Cheers

 

[aucky]

The leak from the rocker cover is very common. People don't seem to be bothered about it as its so small.

 

[Sir_Dave]

The leak from the rocker cover is very common. People don't seem to be bothered about it as its so small.

This.

Pretty much every 182 does it, mine certainly does lol ... im sure ill sort it out at some point, but not whilst its cold/wet/dark outside.

 

[Cue]

oil in the inlet manifold is fairly common - it'll even git into the throttle body. It's not a great amount to worry about.

 

[Sam_K]

Yea mine was done under warrantee when it was about two years old i think, however they changed the cambelt too as apparently oil had leaked on it. I think if your piston rings were shot you would have more noticable symptoms, loss of compression etc? correct me if im wrong though?

 

[hoolio]

I was just about to say the same thing as Cue or that the oil had indeed dribbled down. The oil leak from the "gasket" is fairly common, maybe over time the heat affects the "gunk" though it can be expensive to get sorted and is a good thing to get sorted at the same time as the cambelt.

 

[Robh18]

oil in the inlet manifold is fairly common - it'll even git into the throttle body. It's not a great amount to worry about.

How and why does it get there? And also would this small oil leak on the rocker cover explain why there is very small amounts of oil on top of the pistons and oil around the threads of the spark plugs ????
From looking down the spark plug hole i could see the piston head and it seamed to be a very dark colour as if the car is rich running is this a normal sight for a 182 piston head ??

 

[liam1610]

Well from what you posted all of this is normal for a 182. Mine is leaking from the cam cover and its only sealent theres no gasket hence why it leaks in the first place.

You was rite to get it done with a timing belt change due to the cam cover holds the cams in place on these engines. As for oil in the spark plug well's thats expected too as its part of the cam cover and that can leak due to yet again sealent and no gasket.

As for oil in the inlet manifold and the throttle body, if you have the breather still attached and no catch tank fitted then your get oil from the breather through the throttle body and in the inlet manifold. Another leak that you may notice is possibly valve stem seals they cam leak very slightly but until you get the head gasket go or you replace pistons ie for an upgrade there's no point in worrying about this.

Now for the oil or as you say dark colour on the pistons, your rite if it was oil it would burn of, if the piston rings were leaking you would most likely use alot of oil not just small amount's, i think my common usage of oil is a max of 1/2 ltr every month if that Also with piston rings your most likely notice scoring on the bores too. What its more likely your seeing is carbon. This happens on every engine, from what iv seen these engines run lumpy on idle, now this could be due to the carbon build up on the pistons or it could just be a fueling issue on low idle. Having never owned my T from new i cant say if the engine had got lumpier over a period of time.

There is ways of removing this carbon buildup some people say to use additives in the fuel system to clean but this wont remove it all and iv never used these myself. The one thing that does work for carbon is water especially if you have a head gasket go with a leak to water, the cylinder with the leak will always have a shiny top to it. Now i know there is such a thing as a water injector, iv ever seen it on dragsters due to throttle body temperatures, these engines when running have water sprayed on or into the throttle body to cool the system down, by doing so this then helps to clean buildup of carbon on all engine internals such as pistons and valves. It can be added to a standard road going vehicle iv seen it on a peugeot 106 gti turbo. Its alot of hassle to install and imo not worth considering.

 

[stormduck]

If your rings were gone the burning oil would be causing obvious blue smoke from the exhaust, you'd be down on power quite obviously. Fill up with Shell VPower and that will clean up the carbon deposits in the head and pistons. Supermarket fuel will cause excessive carbon build up.

 

[liam1610]

Thats slightly miss informed information. Better fuel wont clean carbon build up on pistons and there is a reason for this, this is due to certain engines the way there manufactured run better with a carbon build up. I work on one manufactures engine that i know runs better with a carbon build up this being Posrche especially there newer engine's.

Now i know that BP use to do there display at say Goodwood Festival of Speed when they use to show a probe of an engine one side run on 98 ron and the side run on 95 ron, it was a load of rubbish and without a water injector you will never get an engine so clean without stripping and rebuilding.

 

[trophy380]

Get them to do a compression test on it. I wouldn't worry about the little amount of oil that's landed on the piston, People use to do compression tests by placing a little oil in the bores anyway to test if the rings would leak! Most likely it's like you said, that a bit of oil has run in or quite possibly the stem seals could be leaking slightly.

 

[Robh18]

If your rings were gone the burning oil would be causing obvious blue smoke from the exhaust, you'd be down on power quite obviously. Fill up with Shell VPower and that will clean up the carbon deposits in the head and pistons. Supermarket fuel will cause excessive carbon build up.

I have only ever run on shell V-power never put any other fuel in.

 

[Robh18]

The responses to the query has been great guys really appreciate it. Managed to get some pics of the engine today take a look, and as you can see there is small amounts of oil sitting where the inlet manifold sits. What do you recon to these pics ?

 

[liam1610]

To me your pic's are a tad blurry when expanded however it looks as though you have the same oil leaks i have on the cam cover one being on the front common leak and the other being from the bolts yet again common leak. As for oil in the manifold, give them a clean with either brake cleaner or if the company thats doing the work has a chemical cleaning facility then they can do a quick wash in that, it works wonders, at my workplace we wash items like that in the chemical cleaner gets rid of all oil and dirt in a rather quick time, i then steam clean the items off then blow gun them dry especially the fixing holes. The reason for steaming is the chemical they use can deteriorate rubber gaskets mainly.

When you get the car back home check the throttle body for oil residue see if that needs a quick spray with brake cleaner and a rag and i would check the breather, the inlet system may be covered in oil due to someone overfilling the engine with oil and the excess oil going through the breather to be re-burnt in the engine.

Make sure while the timing belt is being down you get the cam cover done too saves extra costs at a later date.

 

[Robh18]

how could it be leaking past the bolts ?? surely they would be make a tight seal ??

 

[Gazza]

how could it be leaking past the bolts ?? surely they would be make a tight seal ??

Mine also leaked through the bolt holes, which I think is also related to the liquid gasket not sealing properly. They did replace my bolts at the same time

 

[liam1610]

There is a cheap fix for the bolts that leak but unless your confident in doing it i wouldn't suggest it but here it is, you can remove one bolt at a time use a bit of sealent around the head then re-bolt it back down, ideally its best getting the whole cam cover done as it will most likely leak sometime after doing the bolts but its just an idea for a temporary fix.