If you don't like the CF3 pistons, you could use CF2 pistons, rings and head gasket set.

 

sure pistons cf2 ?



Cf2 pistons have some different qoutes in dimensions.
Are you sure , but sure, that there will be no interferences somewhere??

I hope you are still available online.

Thanks

 

If you look at this page Alfa Romeo 147 Club • Toon onderwerp - Zuigerveren vervangen 1.6 Twin Spark you can see that the pistons have no holes for the oil to escape.New rings might help but not cure the problem totally.
Best would be to make some mods to the pistons as well.
I`m thinking of doing same mods to my JTS pistons and then I see what is the result.
I´m planning to leave old rings in place to make one thing at a time to see what actually cures the oil consumption.
Mine has done 85000 km and consumes 1L for 3000 km.

 

I can confirm that this modification on pistons works on JTS and TS!
No need for 4 holes on each side, 2 holes (on each side) in the oil ring groove is enough

BTW I do not understand why this holes are not made in original piston???
and why rings are smaller????

 

Thanks guys.
@Pud237 - trying to keep costs down, so not keen on getting CF2 pistons, but great to know it could work. Looked at the ring glands on a CF3 piston and there is not really enough space to cut and fit "thicker" rings.
@Kristop - will check my pistons when I strip it next week, but CF3 pistons seem to have four holes just below ring glands.

 

Engine stripped in place. Sump contained a black tar type of coating ( not quite sludge) likely caused by a “blend” of the different oils and additives I have been experimenting with over the past 100 000 km’s to try and magically curb the engines oil consumption.

Head was reconditioned, received a light skim and Reinz valve stem oil seals were fitted.

Main end bearings were not replaced as they were in as new good condition.

Crank journals showed no signs of wear, but big end bearings had small pit marks that seemed to have been caused by something other than wear. Will post pictures later. Big ends replaced with King Bearings ( King Engine Bearings) made in Israel.

The CF3 pistons were in good condition with no abnormal wear in ring grooves. After being a bit hesitant, we drilled four 1.5 mm holes in the 2.0 mm oil ring groove of each piston. Chose a smaller diameter as shown in the pictures as I was not too keen on the “burr” effect of the larger holes in the pistons shown.

The bore still had factory hone marks showing, but rings were fairly worn. This engine had an oil consumption issue from new, so it would be stupid to again risk fitting OE rings that was partially responsible for the problem; rings therefore fitted were standard NPR (NPR of EUROPE| Automotive Technology) made in Germany - has anyone used this brand before ?

 

The bore still had factory hone marks showing, but rings were fairly worn. This engine had an oil consumption issue from new, so it would be stupid to again risk fitting OE rings that was partially responsible for the problem; rings therefore fitted were standard NPR (NPR of EUROPE| Automotive Technology) made in Germany - has anyone used this brand before ?

Did I understand right that you put new rings in without honing the cylinder bores.
Were the new oil rings more open type to allow oil to flow through better ?

 

4 holes on each side of the piston or 4 holes in total (2 per side)?
What was exact oil usage before?

Please report of oil usage after running-in period, I would like to compare to my experience.

 

Sorry, 4 holes in total i.e. 2 per side.
Oil usage about approx 1 litre per 1500 km.

I will post regular updates on oil usage and anything else of interest.

 

My experience with new rings and 4 holes in total was droped oil consumption on JTS from almost a litre to 0,2 per 1000 km (normal vechicle use, or slighty more for sporting use)

 

No, we did give the bores a light hone before assembling.
I was just indicating that despite the engine being 10 years and 136 000 km old, that the factory hone marks still showed - in other words, that after 10 years the rings had not worn/glazed the bore to the extent that it even removed all of these marks.
Very much a case of "soft rings/hard bore", which makes it possibly to replace rings on standard pistons instead of a much more expensive reboring/resleeving and fitting of oversize pistons.
On the other hand, I have also read that some Alfa Romeo engine builders blame excessive factory honing that led to deep bore marks, as being partly responsible for oil consumption issues. So maybe I should not get too excited about limited bore wear - maybe the marks were simply too deep when the car was new?

 

Not likely. To get deeper marks the grit on the stones would have to be coarser. All that excessive honing would do would be to make the bore larger. These engines rev freely because they are not built to tight tolerances. It's also why they are prone to oil usage and often need a rebuild at around 100k. I've stripped lots of engines with 200k + on them where the bores are perfect with visible hone marks like yours.
I'm surprised you used the old mains shells again with the big ends showing signs of wear.

 

As mentioned in the original post, the rebuild was done with the block in place i.e. only head and sump off.

Below are pics showing block assembled, crank with sump off & a main shell........... all were similar condition

 

Did you use Alfa rings?

I despise the solid oil ring design. They clog up and start smoking o Alfa. BMW and a lot of other manufacturers.
I only use ring sets that use 3 part oil rings. Without drilling holes in the pistons they cure the oil usage.
In my experience.

 

Although car never smoked, the rings were badly clogged up. I was a bit pressed for time so could not really shop around that much and had to settle for what I could source locally at a decent price.
Bearing in mind that this motor suffered with excessive oil consumption since 30 000 km, I was not going to use Alfa parts at all and in the end used NPR rings NPR of EUROPE| Automotive Technology

 

The cats got rid of the smoke

 

Yeah, you told me in March 2012 already to get rid of the cats in this topic
http://www.alfaowner.com/Forum/south-africa/324751-decat-2003-156-2-0-ts.html
but the front ones are still in !

Will get them done NOW!

 

Any experience of oil usage after running-in period?

 

Ran motor in on a Shell Helix Diesel HX5 15W-40 oil known for its detergent qualities. Wanted to do only 1000 km before oil and filter change, but ended up doing about 1700km in one trip where I kept revs below 3500 rpm. Oil level per dipstick with engine cold i.e. as much oil in sump as possible, dropped by about 2mm!

All drained and new oil and filter fitted. I was so excited about the oil consumption that I became "brave" and filled with Shell Helix Ultra 5w-40 full synthetic and so far NO oil usage at all after about 1000km.

 

The Alfa oil rings are ****... the 3 piece rings are much better.

 

Resurecting an old thread... how difficult is it to do rings and shells DIY? with engine in situ?

 

It's not too bad. Getting the sump off is a pain as you need extended ribe tools and breaking the sealant takes patience. Putting it back is no fun either!

The actual mechanics of the job is not difficult. Click the link in my sig to my rebuild thread. May give you an idea.

 

Guys,
do you have any update to this? Is the upgrade by drilling holes to the piston still working fine? What is the oil consumption now?

My 156 2.0 JTS eats like 1l / 1500km, but it depends heavilly on the driving style. Worst case is highway, when the engine runs permanently above 3000rpm.

I'm considering doing this upgrade to my car during changing of the timing belt and pulleys, which is due in next 10 000km, but I would like to know if is it worth doing or not.

Thanks a lot!
Zb.

 

Piston rings

Hi, i think i have to rebuild my 2 litter twin spark engine which used to drink 1 litter oil per 1000kms or less, and i read that there are piston rings that cure this.
Can someone please point me which ones i have to buy?

Regards

 

No one?!

 

3 piece oil control rings is what you need. It's the oil control ring setup that causes the issue: either fit 3 piece rings or drill oil escape holes in the oil control ring groove.

 

But what brand sells this kind of rings, are they a simple installation or are there modifications to be made?
Regards

 

Try our friends at Autolusso or Alfashop, shop4parts, or Alfa Workshop.

 

Rebuilding a Twinspark & JTS

Please read the whole thread again.
CF2 pistons have thicker oil rings. If using CF2 rings, CF2 pistons and CF2 head gasket is needed.

Personally, I'd drill oil return holes in the CF3 pistons as I've read on here it works very well for CF3 TS & JTS.
I think all aftermarket rings use 3 piece oil rings. The issue was Fiat's cost cutting. The blocks were bored and honed in a single operation. That's why the hone marks are very deep.

I rebuilt my JTS but didn't drill holes in the pistons. After 20k, the oil consumption is back to a litre every 1k (miles). That said, a PAO or ester based oil makes a big difference and costs less.

Blackness from oxidation in the sump (and elsewhere) is due to low quality oil. Obviously the oil oxidises and there are not good enough detergents and dispersants to prevent the formation of varnish or sludge. Shell excels in this department but a JTS may prefer Motul X-cess or Millers CFS with NT+ to keep oil consumption low. Gulf Racing is another ester based oil but because I is a racing oil, it has not undergone the costly certification process. I don't know if it is good enough that way to be used long term and I haven't tried either.

CF3 engines used lower friction rings and pistons for emission reasons. It should go without saying that CF2 (oil) rings therefore have significantly more material and hence a stronger spring = more efficient seal.

When I rebuilt the CF2 TS and the JTS, both times I used Federal Mogul parts (Goetze rings).

50k later, the TS is still oil tight but the JTS really needs top tier oil to keep consumption down because I did not drill holes in the rings.:grumpy:

 

I use Gulf Competition (not the same as Gulf Racing being more ester based than the Racing), and have done for many years and over 100,000 miles in both my old CF2 TwinSpark and my present JTS with no problems.

 

Fruity;17292847]Please read the whole thread again.
CF2 pistons have thicker oil rings. If using CF2 rings, CF2 pistons and CF2 head gasket is needed.

Different oilrings means different head gasket ? it seems with no reason ! are you sure?
The CF2 pistons are some 0,7 mm higher .Maybe the reason for different head gasket ? ( attached jpg)

The CF2 pistons are 5 mm deeper . It means they are more driven but more heavy ?

Personally, I'd drill oil return holes in the CF3 pistons as I've read on here it works very well for CF3 TS & JTS.

?? I'd ?? I whould drill ..? sorry I'm from Italy
Do you racomand it ?

I rebuilt my JTS

Jts is obiusvly CF3 , right ?

CF3 engines used lower friction rings and pistons for emission reasons.

Does it mean that using CF2 oilrings the engine will loose Euro4 cat. ?

When I rebuilt the CF2 TS and the JTS, both times I used Federal Mogul parts (Goetze rings).

Are goetze 2 mm oilrings for CF3 in 3 parts ?

What do you think about changing 2 mm originals oil rings with goetze and bohring holes ? Maybe enought?

to be continued
( my engine is still disassembled . Ask for any pics )

 

Don't mix CF3 parts with CF2

Gigioone,
CF2 pistons have a greater deck height which is why they must use the thicker composite head gasket.

CF3 engines have a multi layered steel head gasket which is thinner.

CF2 engines have a 3mm thick oil ring.
CF3 engines have a 2mm thick oil ring.

CF2 and also CF3 pistons, rings and head gasket are all a matching set for each version.

CF2 pistons will be heavier but it won't make mach difference but if you change to CF2 parts it may be necessary to have the crankshaft balanced.

Search for VAG TSI pistons to see the oil drain holes on aftermarket pistons.

You would be looking to drill 4 holes in total of 1.5mm diameter. They would be from outside the piston to inside. Each hole would be 20 degrees from the centre of the gudgeon pin but check the underside of the piston to ensure you won't drill into the gudgeon pin boss of the CF3 piston. You want excess oil to escape.

The main issue is the bore finish. If it is deglazed, there should be no issues but drilling oil drain holes seems like a good idea as per others' comments.

 

Geotze rings are 3 part rings

All Goetze Twinspark and JTS oil control rings are 3 part rings. There is a ring, a spring and a wire.