Technical Oil pickup pipe bolts

[Mike1alike]

Fiat Punto mk2 1.2 8V. I'm having low oil pressure on idle, about 10 psi. Cold engine start pressure is ~60 psi and is the same when revv up, pressure rises immediately as revving up.


So I went to check the pickup pipe. Got the oil pan out nice and when I got to the pickup pipe the rain started and I couldn't figured out what size these bolts heads are. It's not T25, nor T27. Tried a little the Allen 5 mm, didn't feel it's that either.
Can you tell what's the bolts head size on these?
Thank you!

 

[judderbar]

Fiat Punto mk2 1.2 8V. I'm having low oil pressure on idle, about 10 psi. Cold engine start pressure is ~60 psi and is the same when revv up, pressure rises immediately as revving up.


So I went to check the pickup pipe. Got the oil pan out nice and when I got to the pickup pipe the rain started and I couldn't figured out what size these bolts heads are. It's not T25, nor T27. Tried a little the Allen 5 mm, didn't feel it's that either.
Can you tell what's the bolts head size on these?
Thank you!

Be Ribe i expect. Easy to buy a small set from a car shop

 

[Mike1alike]

Yeap, they look Ribe to me, too. Maybe M6?! I'l try find and get a set tomorrow.

 

[Mike1alike]

I didn't manage to find a Ribe set in any local store, physically. Just online, but that takes time till delivery.
But I managed to get the screws out using a Torx 30, went really well. It was hard to get a grip on the second bolt at first and I thought there must be some dirt inside blocking the torx and it was so. Pretty much cooked up oil, got it out with a little screwdriver and then it went well.

I've expected to find the pickup pipe cracked, like I've seen in other related similar problems. But it isn't cracked.
I did ordered beforehand a new gasket. I don't know if the one on the pump had air leaks and caused suction of air instead of oil, but anyway a new gasket is mandatory after this job, in my opinion.
The sieve was very dirty, clogged and when I first saw it I thought that that is the problem. But it is not only that, it is broken, too.
So I ordered a new pickup pipe, original part, will have it in 1-2 days.

Forgot to mention in the first post, the oil level was a little low, but not below Min, about 20% up between Min-Max marks. And oil was due to change, I've had it since August last year and drove about 1.000 km.
Now I think the cause of low oil pressure might be that dirt like the one on the sieve got up to the oil filter and it was in about the same stage clogged as the sieve, without being broken like it.
Hope the new pickup pipe and cleaning the oil pan to be the fix. Will put new oil an new oil filter, of course. It's the first time I've taken the oil pan down, the car did over 260.000 km.

 

[AnthonyH]

These old cars consume a lot of oil, just aswell the oil is cheap!

 

[Mike1alike]

These old cars consume a lot of oil, just aswell the oil is cheap!

If they do, there is always a technical reason for them to do so.
Mine was consuming oil 10 months ago. The reason was worn out valves seals. When I replaced them, I've also discovered that the oil feed line inside rocker cover was blocked, it would splash just a little oil on the little outings, the main outing points that goes to camshaft bearings were totally blocked.
This is me unclogging that line with diesel and a big syringe.


This problem I had now, low oil pressure on idle, it's also not good for the engine or the oil consumption. Watching again the oil pressure reading videos I made (I made 3) I saw that the needle went down even below 10 psi, kind of to zero. It was just enough so the warning light not to pop up on the board. That very low pressure shows in the video I've posted here, this is the 3rd I made, the oil was getting hotter, getting to working temperature. That us definitely not good for the engine, not good at all.
Normal pressure for oil 100⁰C is ile 13 psi/0.9 bar and 4000 RPM - 60 psi/4 bar.

 

[GrandePunto PL]

Normal pressure for oil 100⁰C is ile 13 psi/0.9 bar and 4000 RPM - 60 psi/4 bar.

Minimum, to avoid warranty/recalls. You should get a bit more (my 1,4 8V has 1,2-1,4 bar at idle, hot oil).
Same with oil consumption (numbers from service/owner's manuals are NOT "normal")!

 

[Mike1alike]

I got the new pickup pipe. It comes with its own new gasket so I didn't also get the first gasket I've ordered before.
These are the codes for them, if it helps anybody sometime.


So this is how that new gasket looks like. I say that most certainly that worn gasket was the reason for that low pressure, oil pump sucked air there.


I've cleaned the pan and I will paint its exterior, found this spray paint that looks good for the job.
It's still raining here so I didn't yet got to clean the engine block surface, will do it next days.

 

[AnthonyH]

If they do, there is always a technical reason for them to do so.

You've done a great job there! Older engines can be repaired to continue for many years. My Punto EVO is on 124,000 miles, its not using over the top amounts of oil, but enough for me to be topping up every few weeks. The car is too scruffy and in need of too many minor repairs for me to recondition the engine with new valves etc.

 

[Mike1alike]

I painted the oil pan, looks better. I did a little the inside too cause there were some rough rusty patches, I didn't like those.

I must mention the adaptor I made for measuring the oil pressure. I used the compression tester gauge, I just disconnected the valve that locks the needle on the higher registred value (as you need for compression test) and connected a hose there. At the other end, as the tester's thread is different pitch, finer and couldn't use that, I used an old oil pressure sensor. I drilled that using a 3 mm or maybe 2.5 mm drill (I used what went through the original hole in the sensor's metal part), cut those indentations from the plastic part and connected a hose there.

The rain stopped now so I'm gonna clean the engine block side and put everything back together.

 

[Mike1alike]

I've cleaned up the engine block side, Saturday. And yesterday I put the sump and everything back.
Today I'll fill it up with oil. I have a little bit of emotion to see it doesn't leak oil, but I'm confident it's ok. I used Reinzosil sealant.

And I bought new pickup pipe bolts as the new pipe came without bolts. M6x25mm. I've picked up (pun intended!) bolts with Allen 5 head and put a washer too because the exterior diameter is slightly smaller than the one on the original bolts.
I don't think that I'm gonna test the oil pressure again now. Because I don't want oil drippings again (even if is just a little amount while connecting the tester) and I am very satisfied with what I have done. It should work great now.
A beer for me for a job well done! Cheers!

 

[Mike1alike]

The engine runs great now. Can't say it ran bad before, probably (or most certainly) the fact that I've been using MoS2 oil additive helped a lot, engine never overheated. But now it's something else, it runs perfect.
One detail I've noticed. On the first drive I had the impression it takes forever for the engine to heat up. That's just because I was used to it instantly heating up. It would just warm up to the first corner. I really thought the thermostat was broken, stuck open. But it's ok, I've monitored it exactly the next day and it heats up as it should.
Driving on at 12⁰C atmospheric temperature, engine heating up goes like this:
1. After 5 mins., 1.7 km, temperature needle starts rising
2. After 9 mins., 2.5 km, temperature needle was at the first thick line, 25% on the gauge, 50% working temperature
3. After 13 mins., 3.1 km, temperature needle was at the 6th line, 75% working temperature
4. After 21 mins, 5 km, temperature needle was at the 2nd thick line, 50% on the gauge, 100% working temperature.

And another detail, after needle hiting the second thick line, driving away after waiting on the stop lights, the needle would go slowly down to the first line below. No sudden jump, slowly moving. I think that's pretty normal, it's the leeway of working temperature from cold air heating the radiator and cooling down the coolant and thermostat closing down. But that never happend before, I've never noticed that. Before, once the needle hit that half mark on the gauge, it would stay there, bang on.

Thinking back, when I measured the oil pressure, I guess that good numbers shown while revving up was not actually 100% good. I mean that pressure was most likely made by oil + air, meaninig the oil volume sent through channels was less than optimal.

I'm very pleased with this job!

 

[chevychase]

What made you want to check your oil pressure to begin with? The Punto has no oil pressure gauge, so something must have made you investigate.

Good work though, something I'll refer back to if I ever need to.

 

[Mike1alike]

Couple of months before checking the oil pressure I had problems, the engine would not run at its best. It would stall, it shut down at traffic lights a couple of times. That was due to bad TPS (throttle positioning sensor) and I fixed that, put a new sensor in. But untill fixing it, the oil pressure light popped up on the dash a few times. And I remembered it lightning up even when the engine was just stalling, not shutting down. That made me wonder what's going on with the oil pump, how is the pressure. After putting in the new TPS, the oil light never light up again (except of course, when starting the engine and so), but that stucked with me, that I should read the oil pressure. And I did!

 

[Mike1alike]

Driving on at 12⁰C atmospheric temperature, engine heating up goes like this:

I will post a follow up here, although this thread name is completely different. Anyhow, things are all related so, considering my previous mentions about engine heating up timings I think I can continue here on that.
Turns out the thermostat was faulty earlier. Needle shouldn't move down on the gauge once it gets to working temperature. The middle line corresponds to a range of degrees, it's not for a single number. The needle hits the middle line at 80⁰C and stay there at 94⁰ too, probably a little more above 94. My previous temperature monitoring was wrong because I based it on the gauge and didn't have the exact temperature. The thermostat's internal gasket was damaged there so it couldn't close completely anymore. The engine ran actually at temperatures between 70-80⁰C there, or so, underheated anyway.
So needle moving down, under the middle line is a clear indicator the thermostat is faulty, it can't close enough.
This is a graphic of actual temperature. It clearly shows engine doesn't get hot enough. And I could see that when I turned on the heat (and the heater fan blew on the heater matrix) the temperature would drop actually, which shouldn't happen.


The thermostat
It's quite very ingenious thing the thermostat, how it works.
And there are endless discussions coming from the question if thermostat should close completely or not. It's really up to the maker that. There are some that does close completely and others that have a little breather that allows a very small flow.
I had one Calorstat by Vernet (TH5069.87J) thermostat in use, the internal gasket failed on it and it wouldn't close completely anymore. This one has a breather, you can see it in the picture. It is very small.

The space in the middle in the first pic is where the gasket sits. It broke on this one, I got a little part coming out of the radiator breather when I bled the system after putting new thermostat in. I shall get the radiator down in the spring and get the rest of it out, also clean it on the inside.
I got a Thermotec (D2F008TT) thermostat now. There is no breather on this one, so it does close completely. I blew into it to test it and the air didn't pass through. Here it shows the gasket, I'm just sorry I didn't take a pic of inside pipe as this is a little bit different and can't find a pic on the internet.

So the engine heats up quickly than my previous observed timing. It gets to working temperature in 7 mins, driving 2.7 km. And the temp doesn't go below 87⁰C once it gets there, no matter how fast the car goes and how cold is the air hitting the radiator. Here is a graphic of it.

And a little note here. This thermostat closing completely, it wouldn't bleed completely when cold. And on the first ride, having a little bit of air in the system, the temperature would drop to 84⁰C. So that's an indicator, a very good one. If temp drops below 87⁰C while driving, there is air in the system. Once heated up I could easily bleed it and temp stays 87⁰C minimum afterwards.

And here are some pics with the main character, the thermostat, here missing its gasket. And this is how it works, the ingenious principle. When I put it in hot water the little shaft in the middle of it came out. And it wouldn't go in if I pressed on it. When it got colder and I pressed it, it did go in.