Technical Excessive oil consumption

[randomizered]

Its been high since the latest swap, but is really getting on my nerves now. I was planning on doing some work to fit cams etc, so will need to look into this.

Compression test values are all within tolerance, no smoke at idle, no visible smoke from drivers seat under load.

No leaks anywhere.

The only places i can imagine i need to check are the piston rings/pistons and the stem seals...are there other areas that i should keep an eye on?


Excessive is defined as probably 10L in the last 10-15K, about 3-4L in the last few thousand....its now below minimum again

Kristian

 

[rallycinq]

A litre per 1000 miles is not excessive on a modern engine.

Check that the induction vacuums are all in the right place.

Cheers

D

 

[randomizered]

It may be more. I suppose as i have access to a 100hp and my own car as well so i could do a side by side comparison to see how they do against each other.

It does seem a lot, but i may just be focusing on it too much, and looking for an excuse to strip it


I'll buy another gallon tomorrow, and measure it all out in a pyrex

Cheers,

Kristian

 

[allanhelen]

D is right i know of quite a few cars like that.

What i find on the Cinq's is that if you top up to maximum they will always use half the amount between max and min,

if i keep it halfway between min and max on the dipstick they don't use any

Maybe this is one of the tricks to longer service intervals?

 

[levemircento]

What i find on the Cinq's is that if you top up to maximum they will always use half the amount between max and min,

if i keep it halfway between min and max on the dipstick they don't use any

mine is like that too!! cant see where it would go, theres no leaks, and it never gets burnt in the engine and there is never any blue smoke.


kritip, the oil loss could be through the valve stem seals, it would show up as puffing some blue smoke out on cold startup, would be very noticable.

 

[J333EVO]

It has been noticed on our 1368 engine that it uses way more oil than the old 1108 ever did.

In fact is easily uses more oil than either my Celica or integrale do.

Though 3-4L in a 1000k is excessive IMO, I know from owners manual the integrale is within tolerance when using 0.5-1L per 1000miles, mine uses less than that, maybe 0.5L-1L every 3000miles. The Sei is using about 1L per 1000miles which I think is fairly normal.

The Celica in 2000miles has used none, still sitting bang on top mark after last change, though needs a change again in 1000miles.

Aaron.

 

[fingers99]

The classic Alfa and Lancia motors used to get through about 1 litre in 1000 miles: in their time, this was regarded as rather quaint, Italian and excessive in a mild way.

You have marginally high oil consumption and an engine that is running hot. What oil are you using? What's the mileage on the engine? Any fuming from the oil breather?

 

[randomizered]

I forgot to update that temperature thread, that was down to my error. The temps are actually fine

The crank case breather is fed back to the intake at the moment. I have had a catch tank for ages but never fitted it, maybe now is the time, or just stick a little filter on it so see what its putting out.


When the engine went in, I used Selinia 20K, and since then its been topped up with 10w40 semi from Halfords. The engine only had 8K, a rear ended panda, and has done a further 10K ish now, so very low mileage.

Before I investigate by stripping, I gonna give it a service.

New filter, and I'm gonna put in some 5W/40 FULLY synthetic, and accurately measure consumption, then I'll know for sure if I have a problem.

I know my Mothers 100hp likes oil, and if Emma's is also a bit thirsty, maybe I just made an error in my calculations.


Cheers for all the input

Kristian

 

[fingers99]

I was wondering whether the rings had fully bedded in. In my experience they can need 10,000 miles plus, and fully synthetics don't help bedding in at all.

 

[randomizered]

Yeah, I have only run semi so far and should be bedded in by now. I'm only gonna go fully synthetic, as Halfords a have a deal on for free sockets set from the Professional (aka lifetime warranty range ). also if it does turn out to be normal consumption, and this is a service period, it will be niec to have fully synthetic in there now

I'll do the change tomorrow, I should easily knock up a thousand in a week or two, then see how much it's used. Fingers crossed its not too much


Cheers,

Kristian

 

[randomizered]

Had another check over before dropping in the new filter, oil etc.


Did actually notice a bit of smoke in the exhaust today at idle , so out came the compression tester again.

Here are the results:




Cylinder-Cylinder compressions are fine. Number one is low, but number two isn't so its not gone between cylinders (as expected. It doesn't look like a gasket problem to me.)


Coolant is also fine.


Is this wet test typical even on good cars/pistons? Are the rings still bedding in?

So many questions to answer, and lots of reading to do. Last thing i want to do is waste £37 of oil if it needs stripping.


Kristian

 

[fingers99]

Know anyone with an endoscope?

My guess is that it would show that no.1 isn't bedded in yet.

I think you can afford to put some semi-synth in and run it for 5k or so before you have to decide.

Did you do the test with the engine well warmed up? (No.1 will be the best cooled cylinder).

 

[randomizered]

The fully synth and new filter is in. It still seems to smoke a bit. I'm keeping an eye on consumption, but doing very little miles at the moment.

TBH, I think I may have taken a ring out, after tuning to aggressively for economy, but I'll know for sure in a few weeks.

Cheers,

Kristian

 

[randomizered]

Puffing a bit more on startup, especially when its been turned off warm.... also there is a slight popping back up the inlet when idling

The popping is only going to be caused by an inlet valve isn't it? not the seals etc.

I haven't verified cam timing...maybe i should have done this before I fitted it

Will prob end up stripping it this week...hopefullly its a top end issue!

Kristian

 

[fingers99]

Popping would be a valve not seating fully (a bit worrying with hydraulic tappets).

Take a peek at the bores while you're in there: I have a 50,000mile Sei which still shows honing marks on the bores (don't know the history, but it's a bit odd).

 

[arc]

My 1242 engine from a P75 still had honing marks on the bores at around 60k. seems to be a FIAT thing!

Does sound like something is amiss. Just looking at your compression test results; i did mine today, and each cylinder was ~203 PSI

 

[randomizered]

Def something amiss!

Just took it down to asda, on the way back, gave it a bit of stick, 6,000rpm, and got a funny rattle that i have had for ages with this engine (ie. day one), and then it dumped LOADS of smoke over the road behind me lol. The sound isn't det or pinking btw

I may start stripping tomorrow...just stuff is so expensive compared to 8v. Just the gasket and bolts are about £80+

I may possibly run a comp test on the panda 100hp as well, see what that gets.....just don't wanna trigger a MIL on it!

Kristian