ALFAGTV6.COM

Seb · Post by **Seb** » Thu Oct 06, 2005 3:42 am

Hi guys!

Now that my 3.0QV conversion of my GTV6 is done and I have it up and running, I´ve run in to some problems. I have low oil pressure.
Cold at idle 4 bar. Warm, driving 1 - 2 bar. Warm idle 0 - 0,5 :-/

Thread here: http://www.alfagtv6.com/bb/viewtopic.php?t=88

But before asking some qustions what to do about it, I have to explain the situation, so bare with me.

The 3.0QV engine from the 164 has its dizzy on the back of the LH cylinderbank. Since the dizzy isn´t on the same axle as the oil pump then the gear for the pump is doing 1,5 rotation for every engine rotation. So, there is a higer rotation in the 3.0QV original.
On the GTV6 where the dizzy and the pump runs om that same axle, so I had to put the gear from the 2.5 in the engine so that the dizzy works. That is the reason for the lower pessure!

So now my question is:
Is there anything I can do to get the pressure up, without rebuilding the engine and putting back the 3.0QV gear. I am currently running it on QS 20w-50 Mineral Racing oil.

I now this is a wide area, but I appreciate all the help I can get.

Sincerely Seb

ar4me · Post by **ar4me** » Thu Oct 06, 2005 6:12 am

Have you verified the oil pressure with an accurate gauge (not the Alfa instrumentation gauge)?

Doesn't the Motronic for the 24v 164 use coil packs - no distributor? Didn't realize it uses a distributor

Jes

Seb · Post by **Seb** » Thu Oct 06, 2005 6:20 am

Jes, its a 12v, so it has a dizzy.

No I havn´t checked with an accurate gauge yet, just discovered the problem yesterday. Will do.

Seb

Barry · Post by **Barry** » Thu Oct 06, 2005 7:23 am

Seb,I concur with Mats,get a mechanical gauge to test-I reckon your pressure is good.The sender units always fill up with oil and dont work as when new.I cant see that a slower pump speed is going to drop pressure.All pumps have excess capacity and bypass excess oil..besides,here the 164 pump has the same volume as the gtv6-dont know about elswhere.........

Seb · Post by **Seb** » Thu Oct 06, 2005 10:11 am

Barry!

Thanks for your tips. I will get an acurate gauge to test the "real" pressure. I only discovered the pressure problem yesterday. I will also change oil and filter and try to get a new sender unit.

Some say the rotation speed won´t matter, some say it will. Some say the viscosity of the oil will make a differense, and so on...

I just wanna be able to drive my car

Thanks for now!

Seb

Luis · Post by **Luis** » Thu Oct 06, 2005 10:20 am

I have the same readings since my 3.0 conversion, so don´t worry too much.

David · Post by **David** » Thu Oct 06, 2005 7:55 pm

Seb,
The 3.0L should have a low oil pressure sender beneath the original distributor hole. At least I think that what it's for as I don't use it. Hook up a bulb to the sender and see if it lights up or use the hole with appropriate fittings to fit an oil pressure guage.

My 164 12V 3.0L has heaps better oil pressure than the old 2.5 and I used the 2.5 oil pump, sender, etc in my conversion.

David

Seb · Post by **Seb** » Fri Oct 07, 2005 12:14 am

Ok david, thanks!
But Your 3.0, is it a QV or a regular 3.0? Only the QV:s has the oiljets for the pistons and the different gear for the pump. The regular 3.0´s has the same pump speed as the 2.5´s, if my info is accurate.

The low oil pressure sender your´e pointing to, is it for the varning lamp in the dash?

Seb

David · Post by **David** » Fri Oct 07, 2005 12:47 am

Seb,

Mine is the regular 3.0L. Yes, I think it is the low oil pressure light on the dash, What I was thinking, if you connect a powered bulb to it it should tell you if your oil pressure drops too much if it comes on when the engine is running.

David

Barry · Post by **Barry** » Fri Oct 07, 2005 3:49 am

Seb,you want real life figures here-not just a lamp that inicates on/off..
Fit the master mechanical gauge and see where you are-its the only way..........once you have determined the status you can decide where to go from there.....

David,I know your trying to help,dont mean to shoot you down,mate.....the light indicator probably has a knee pressure of 0.2 to 0.8 bar only-this is no good in figuring out if its a sender unit or the pump and related hardware......

Seb · Post by **Seb** » Fri Oct 07, 2005 4:42 am

Barry, I will, as I wrote further up. Just wondered what David ment.

Thanks a lot for your help guys, appreciate it!

Seb

Bruce · Post by **Bruce** » Fri Oct 07, 2005 5:08 am

At idle with a cheap 20-50 oil I have 5.5 bar cold and 0 (indicated) when warm.
With fully synth 10-40 4.5 cold and again 0 cold.
Crusing at approx 2500rpm (~70mph indicated) 2.5bar.
I think you figures are OK.
My car has done 115.000miles (75qv).

David · Post by **David** » Fri Oct 07, 2005 5:19 pm

Barry,

No problem, I agree with you entirely with using a guage. I was just thinking of a quick method using the sender if its still in the block to see if there really was no oil pressure.

David

Seb · Post by **Seb** » Mon Oct 17, 2005 3:52 am

Ok, this is what I will do now:
I got me a MANN oil filter and Selenia 10w-60 oil. This week I´ll get to borrow oil pressure meter aswell, to check my acurate readings.
I hope it´ll nice to me... :-/

I´ll keep you posted.

Seb

Seb · Post by **Seb** » Thu Oct 27, 2005 1:52 pm

Tonite I got the new Selenia 10w-60 in and a new MANN filter. After a testdrive it seems everything is up 1 bar. Idle cold 5 bar, warm 1-1,5. Warm @ 3000 about 2,5-3 bar.

This feels a little better. I syill have to check with an extern gauge and a different sensor. Will keep you posted.

Seb

Oil pressure problems!