156 2.0 JTS worn cam lobes after 60000ks

Started by smitti52, October 16, 2010, 04:22:29 AM

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John Hanslow

Well, my (156 TS) engine had Martini oil supplied by an alfa workshop when regularly serviced.

Can only go on what the dealers and after market specialists are finding - many people purchasing a damaged 156 JTS and get a bit of a shock.   There seems to be a bit of grief out in the 2nd hand market.

Regarding Smitti52 comments, any discussion with an alfa workshop will cobnfirm while not common, the worn cam and poor maintenance (shit cheap oil) has been an issue.

Cheers.


Now:
2011 Giulietta QV

Previously:
1989 164 3.0  V6
2002 156 Twin Spark Sports Edition
2002 147 Twin Spark
2002 916 Spider Twin Spark
1990 Alfa 75 Potenziata

wankski

yep, - its not always nice to point out - and may discourage JTS owners, but the obvious has not been stated....

random worn cam lobes and bottom end damage was never a problem on alfa made fours and 6s.... only when the switch to fiat iron block 4s was made did that become a problem.... with the jts many theorise that the design flaw is inadequate oil ports in the heads, but that does not explain bottom end damage... some blame also the thicker oil spec'd by alfa with the jts, but that does not explain damage in cars that run 10w-40...Suffice to say IMHO, the fiat engine is cheaply made - i mean, iron block? in a performance 4cly sedan? Cheap materials as well as the above - a combination of all these factors - is likely leading to these issues...

alfa have had their problems, but top engine design and materials was always the case, esp with the v6s... wet steel liners, all alloy design, fully nitrided cranks.... some of the most solid bottom ends rolling... also note the cam belt revision from 5yrs/100k km to 3yrs/60k km did not affect the alfa 6s, just the fiat 4s...

that old chestnut aside, merry christmas... have a good break guys... hope the only xmas tree u see is in your living room not on your dash!

Craig C

Quote from: colcol on December 24, 2010, 01:16:14 PM
Re power outputs, my 156 JTS put out a dissapointing 100 h.p. at a Dyno day, i was dissapointed until i got in the car and all the dash lights were flashing, i then worked it out that the electronic nanny had cut power to the engine because the front wheels were spinning at a million miles an hour and the back wheels were stopped, how you would disable it is i do not know!, as it is all linked with the traction and stability control and the ABS, the JTS engine has FOUR Lambda sensors, and one of them are a bit off their best, you lose a bit of power, luckily as i drove home all the sensors reset themselves and all the dash lights went out.

I had the same power output from my JTS (Spider) and when I checked the power curve on the printout it was all lumpy at the top rather than a smooth arc.  My engine light didn't flash (or i didn't notice it do so and then reset) but your explanation would fit with the shape of the curve.  Where did you come across this as an explanation, is there more reference reading out there?
2003 Spider
1984 GTV 2.0

colcol

Re electronic nanny, the only time the stability control light ever came on with me was when i went into a corner too fast and a light blinked that i had never seen before, and if you have ever taken off from the lights too quickly then the traction control light will come on and it will cut spark to the various cylinders to minimise harm, as for cast iron blocks, sure they are cheap and heavy, but a good cast iron block will always put out more power than a good aluminium block but with added weight penalty's, a cast iron block is stronger and maintains its shape better, has round cylinders that don't go out of round like aluminium block and during hot weather they don't expand causing the ring gaps to expand loosing power, look at the V8 supercars all cast iron blocks!, the reason why Alfa have gone to the General Motors aluminium engine now is that the new emmision laws , the law require less emisions in the critical warm up stage, a aluminium with its better warm up due to aluminium transfers temperature better, a cast iron block can be made to comply, but with more and expensive electronics, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

wankski

hrmm...

cast iron, has its advantages (in trucks and very torquey diesels), but like i said, this is in a 145hp tops 4 pot n/a sedan. It should have been all alloy as it was in the TS before it... it was made w/ an iron block outta cheapness, not for any other advantage

cylinders out of round? - any alloy block worth a damn has removable steel liners (wet). This is how alfa always did it. All this combines to of course also make for an engine that has a far better time cooling itself as well cf iron block that is essentially a dutch oven from the bottom of the heads down.. (and half the reason why iron blocks are cheap is b/c they simply bore a hole and there's ur cylinder... burn thru it and.... u're f*&ked..)

as for ring gaps - pfft. the fiat iron 4s are among the worst, iron block or not. give it a good rev and marvel in the sweet secondary function of the 2.0 JTS - smoke screen cover for the land invasion.

the iron block itself can be stiff and strong, but it's all for naught with bottom ends that fail - big end bearings, thrust bearings - all eating the crank like it was made of shortbread. the alfa nord never had bottom end problems, in fact alfa never had any bottom end issues that i can think of period IIRC aside from the crank plug issue which was easily solved by tapping and/or using strong loctite.

Not that there is anything to be gained by belly-aching over a now superseeded engine - but it's just a shame when the shining beacon of alfas were always its no expense spared engines with the best of enginering solutions and materials available at the time (in cruel contradiction to the body construction).

colcol

Re Fiat engines, i would say the reason the crank bearings and camshafts fail is because the owner runs them out of oil, the difference between full and low marks on the dipstick is about 1 litre, that is 1 litre of oil between ok and engine failure, no ones wants to admit they failed to check the oil level  when they should have, they don't want to look like a WALLY, also the oil used in a JTS is 10-60, this is a very thin oil that manufacturers are using because of low drag and therefor better fuel consumption, this is very thin and manages to find its way past the piston rings very easy, therefor high oil consumption leading to low oil levels leading to engine failure, i remember the first time i changed the oil in the JTS, i couldn't beleive how thin it was, as it rushed out of the sump with the viscosity of water!, missing the drainpan i had put underneath it, requiring a good mopping out of the workshop!, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

wankski

oil consumption: alfa engines have always consumed some oil - but it seems to be worse with the JTS in particular. that is still a negative on the JTS. In any case, consumption has not led to this many issues on any other alfa engine. Alfas revised guideline of 1l per 1000miles is way too much any way you cut it.

oil viscosity: on what planet is 10w-60 a thin oil? its one of the thickest at temp you can buy. I know not of any passenger vehicle that takes a thicker oil. the v6 which does not have the smoking ring problem i have seen in the JTS runs a much thinner 10w-40. viscosity is clearly not to blame.

JUST MY OPINION: the JTS oil gets trashed b/c of the first gen direct injection imho. The TS isn't as bad in this respect. I believe with the loose rings on the JTS the fuel getting dumped at much higher pressure thanks to the head mounted mechanical fuel pump (stays in liquid form longer) means that raw fuel is getting past the pistons (loose rings) and dumping into the oil supply. Q: what is one of the best solvents known to man? petrol. Mix that with oil and it don't take einstein to figure out what happens. The efficacy and viscosity of oil quickly goes to crap. This also explains oil levels. When cold, the fuel/oil mix appears at an acceptable level. Fang the car on a long and hard trip and the fuel quickly evaporates from the oil - all of a sudden u are a litre down. No other way of expaining that much oil loss in a short time in a car thats not badly smoking.

again jmo: the 2.0 JTS is one engine you def should not stick to the service book. 20k kms b/w oil and filter changes for this engine is waaay too long. Truth is tho, there is likely no service interval short enough to keep the oil honest.


bix

I'm enjoying reading this topic and thought I would add a comment. I have a 2.0TS which has now done 103,000. I actually ran the engine for over a kilometre without any oil at about 80,000 (I'm too embarrassed to go into detail on that one  ::) ). I change the oil every 12 months and there is absolutely no topping up required throughout the year. Engine is still going as strong as it ever has and doesn't blow any smoke whatsoever.

colcol

Oil Viscosity, i can understand where you are coming from on that, i noted that that the twin sparks used 10-40w oil, but i take it to get the JTS oil consumption down to an acceptable level a 10-60w oil was specified, being a thicker oil it would burn less and not get past the rings like a thinner 10-40w, it is a well known fact that on high mileage cars and oil burners like some JTS's, a thicker oil is used, as regarding oil dilution, you hit the nail on the head!, if the oil becomes diluted with petrol and for city cars that never get warmed up and the oil becomes diluted with moisture, then the oil level may be at the top, take it on a run and all the contaminates get burnt out and the oil level can drop to dangerous levels and you may ruin a motor, i have been told that the JTS's run FOUR Lambda sensors, if they go a bit off song, then the engine managment will richen up the mixture to compensate for any errors that may occur, as opposed to leaning it out which would cause pistons melting due to high temperature, and thats when you start to get oil contamination, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

colcol

bix, I would change my oil twice a year and the oil filter every 2nd oil change or once a year, if you only do low kilometre's per year the oil will get contaminated with rubbish, and  like i said the oil is the cheapest think you will ever put in your engine, check  oil company websites for the recomended oils to use, some drivers have a preference for particular brands of oil, i have no idea what is the 'best' oil as i am not a scientist, you say your engine doesn't use any oil, yours must have been run in properly!, if i had a new car then i would drain the oil out the manufacturer put in, and put some hard to obtain 'running in oil' in and drain it after 1000 kilos and put some good oil in then, i have always done this with all engines i have done and they seem to always run in good and settle down to a long life, like yours that doesn't burn oil, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

avim

Re: the discontinued JTS engine - It was last seen in the Alfa GT JTS which ended its production in mid 2010. This means that the JTS engine had an 8 year run, about the same as a German car.

colcol

JTS, JTS is not so much a motor but the type of fuel injection system, JTS stands for Jet Thrust Stoichemetric which means Jet Thrust = High Pressure, Stoichemetric = Greek word for roughly air fuel mixture, the Fiat based engine that was used in 156's from 2002-2006 in the 2 litre form is completely different to the 2.2 litre General Motors based engine used in the 159, they both employ JTS systems which are direct injection, this is a new system in the Automotive field, but was used in constant speed Aircraft motors in the 1950's, the reason they are now being used in cars is because of the push for better fuel use, and with the constant varying demands on a car motor, a very clever engine managment system is used, due to the advances in computer systems in modern cars, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

bix

I can tell you the JTS 2.2 is no miser on the fuel  :-\
Point taken on 6 monthly oil changes; laziness unfortunately has gotten the better of me in recent years.

colcol

Re 2.2 JTS, it may not be a miser on fuel, but compared to a 156 Fiat engine JTS, it has to haul around a heavier body and the engine makes more power and torque,  and uses more fuel, as a comparison the best my 2.0 JTS has done is 37.04 M.P.G. or 13.22 kilometre's per litre, the worst is 29.49 M.P.G. or 10.53 kilometre's per litre, and i drove 827 kilometre's on a tank, before i ran out!, i drive light traffic, freeway and heavy traffic everyday and i do a fuel consumption check every fillup so i can keep a check on things that may go wrong ie the FOUR lambda sensors on a 2.0 JTS, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

bix

Col. So far my calculations on the 159 JTS range from 9.57k's per litre to the best being 13.3 k per litre which was pure highway driving. Very average for a modern car.