CIH 1.6n no oil pressure ,help

[Raza]

greetings to all,

for 3 days now I have been trying to have any kind of oil pressure, even when I remove the oil filter by rotating the pump with a drill, there is not a single drop of oil.  It gets pressure only when I pour it into the hole from the ignition distributor (2bar). Then the pressure drops back to 0. I repaired this 1.6n engine because there was bad  oil pressure, now I put the cover and pump from 1.9 and it's the same again. The aluminium cover from 1.9  looks the same exept pump cover vith ball and spring. please help:)

[GTEPETE]

Try packing the pump gears with petroleum jelly, which willl create more suction...and fill your filter before replacing to housing...

[Raza]

thanks for the advices I ll try it tomorrow.  

[611]

Check the spec for the pump cover clearance from the gears to the face in the manual as if the gasket is too thick you will lose pressure as the gap will be too big.

If you have the rocker cover off and wind the distributor shaft round with a drill do you get oil coming out of the rockers?? and is the oil pressure sender new or old??

[H-400]

Hi Raza, the old distribution covers had the pressure valve in the cover on the engines right side. The new engines have the pressure valve in the 

bottom plate of the oil pump. Don't mix them, and also the pump bottom plates with the pressure valve must fitted with the pressure valve pointing to the oilsump. 

On both types of engines you must first fill up the oilpump with oil before starting the engine:

You need a 7mm allan key (inbus) to open the filling hole, beware they can be hard to open so clean it to fit the key deep.

After filling the pump I do the same as you 👍, using a drill to pump the oil up till it comes out at the rockers as Andy 611 wrote above.

If you need the specs about the pump gears just let me know.

Succes!

[cam.in.head]

as mentioned above.the early engines had a flat cover on the oil pump and pressure releif was on the side of the timing case just below the large tensioner . if the spring has snapped or the ball is stuck then you will get virtually zero oil pressure .its unusual but needschecking. later engines had the nylon plunger in the oil pump cover.   i must admit ive never needed to prime  any of them myself even when fitting new gears or having had the cover off  ht its reccommended .

if this has happened suddenly then it cant be worn pump gears or bearings so your looking at it from a different angle.

basically oil travels from the strainer up into the pump and then out through the filter and then into the main gallery. ive known the blanking plug between camshaft bearings to pop out and also the gasket to fail on the strainer/suction pipe to block but its rare. 

as you said.spinning the oil pump with a drill into the distributor slot should produce oil out of the oil filter as a first instance .

i would say . study the diagrams in the haynes book and try to be sure that the pickup pipe is not blocked ,releif is not faulty and bypass is ok .    

[611]

Page 16 on the PDF shows how it circulates

https://www.theopelproject.com/l/wp-content/uploads/2020/04/A-Series-Opel-Manta-Engine-Setion.pdf

Even shows how it flows around the oil filter.

Also further along it shows the pressure relief valve in an exploded view.

 

Hopefully helpful to you.

 

Andy

Edited April 13, 2023 by 611

[Raza]

thanks to all 

today I fill the pump with oil trough imbus hole and put some jelly to pump elemets than I had good pressure runing with drill. After I put distributor and run engine there is no pressure at idle, the pressure comes 0,5 bar and red light stop light only at 2000 to 2500 rpm. :(((

I saw that the old chain cover (Opel) that was previously on the engine with the flat pump cover, right above the oil filter, has a 22mm screw with a ball and spring, but this new chain cover (GM) does not have a 22mm screw, but an Allen key that is impossible to unscrew, it is very  damaged.  I don't know if there is a problem, if there is also a ball valve under the imbus hole?

The pump looks good to me there is green thin gasket.

 

 

On 13/04/2023 at 17:35, H-400 said:

Hi Raza, the old distribution covers had the pressure valve in the cover on the engines right side. The new engines have the pressure valve in the 

bottom plate of the oil pump. Don't mix them, and also the pump bottom plates with the pressure valve must fitted with the pressure valve pointing to the oilsump. 

On both types of engines you must first fill up the oilpump with oil before starting the engine:

You need a 7mm allan key (inbus) to open the filling hole, beware they can be hard to open so clean it to fit the key deep.

After filling the pump I do the same as you 👍, using a drill to pump the oil up till it comes out at the rockers as Andy 611 wrote above.

If you need the specs about the pump gears just let me know.

Succes!

thanks, maybe specs about pump gears will be helpfull

[cam.in.head]

if your timing cover has the little allen plug rather than the releif valve nut then it sounds like you have a later timing cover. this uses the oil pump with the valve on the pump cover underneath as mentioned. 

as stated the cover must go the correct way round 

AND  very later versions have no gasket at all. if you put a gasket on where there shouldnt be one you will get the symptoms you have .very low idling pressure if at all.

BUT if you dont use a gasket when you should you will seize the gears up.

you need to measure the gear protrusion which should be 0 - 0.1mm if you have the gasket type. 

if less than zero(ie below ) then you have found your problem  !   you dont need a gasket.  clean surfaces thouroughly and use a flange sealant . you can try the cover without gasket first .insert all bolts and see if the pump turns freely from above by hand / long screwdriver . maybee even a quick try with a LITTLE silicone gasket sealer . it wont last but should  prove the issue .

[Raza]

On 13/04/2023 at 16:39, 611 said:

Check the spec for the pump cover clearance from the gears to the face in the manual as if the gasket is too thick you will lose pressure as the gap will be too big.

If you have the rocker cover off and wind the distributor shaft round with a drill do you get oil coming out of the rockers?? and is the oil pressure sender new or old??

I have 2 new senders one of them is with 2 wires , one wire is for pressure gauge in car. They works good.

54 minutes ago, cam.in.head said:

if your timing cover has the little allen plug rather than the releif valve nut then it sounds like you have a later timing cover. this uses the oil pump with the valve on the pump cover underneath as mentioned. 

as stated the cover must go the correct way round 

AND  very later versions have no gasket at all. if you put a gasket on where there shouldnt be one you will get the symptoms you have .very low idling pressure if at all.

BUT if you dont use a gasket when you should you will seize the gears up.

you need to measure the gear protrusion which should be 0 - 0.1mm if you have the gasket type. 

if less than zero(ie below ) then you have found your problem  !   you dont need a gasket.  clean surfaces thouroughly and use a flange sealant . you can try the cover without gasket first .insert all bolts and see if the pump turns freely from above by hand / long screwdriver . maybee even a quick try with a LITTLE silicone gasket sealer . it wont last but should  prove the issue .

Hi, i wish it was a gasket problem.  I looked at how many gears come out, they stand straight with the pump housing, maybe 0.2 mm come out, I'll try to measure it in the morning.  Another horror thing I'm thinking about is whether I tightened the oil strainer bolts.  Then I'll have to take out the engine again. Anyway, the wife and children think I'm crazy.  I get out of bed in the morning and lie under the Manta all day, sometimes I type on my cell phone))

[cam.in.head]

ok. so if the gears protrude any amount you definately need the gasket. the original gm type is a very very thin green type.

the strainer pipe is a possibility but means sump off. it has a gasket too .

if you have the other oil pump lower cover (flat plate type)try fitting this first. TEMPORARILY...dont increase the revs above 1500 thou . just to check if your issue lies with the releif valve on the other cover. 

have you checked the camshaft / head yet for a missing blanking plug .ive known it happen.its a small plug about 8mm.tapped into a hole.

 

 

 

[Raza]

hi, I have old flat cover ill try tomorrow and dont know what you mean "camshaft / head blanking plug"  Where is that? 

thanks

[cam.in.head]

under the rocker cover you will see all the studs coming up that  the arms fit on. inbeteeen some of them there are plugs inserted into the oil gallery. its not common at all but i have seen a head where one had popped out leaving a hole.

its a long shot and ive only ever seen it once. 

BUT

the fact that you are not getting any oil when you spin the pump with a drill sort of suggests your worse suspicion of suction pipe air leak.   as i said ,oil comes up the suction pipe and straight to the pump first. then to the oil filter. you should see it pump out. try the drill trick with the other cover on .this takes the releif valve out of the equasion..

 

[Raza]

I put the old gears and the flat cowr, the situation is similar.  But I always notice that when I spin down with the drill, a lot of air bubbles are created and the oil is almost white and there is the sound of air mixed with the oil.  I tested the valve in the cover with a compressor and it looks good.  After that I put back the GM gears and the cover on which there was a 0.50 mm gasket, I tried it without the gasket but the gear gets blocked, then I put a 0.25 gasket and then it also got blocked, so I put a 0.35 mm gasket and it was the right thing !! I  got the pressure, with a little gas and 3 bar.  After that, the oil warmed up and at 1000 rpm and less the pressure was again low, almost non-existent, with a little gas it would be 1-2 again.

So the main problem was gasket, but if there is something else I dont know.

Will try later what hapens with pressure when idle and engine warmup.

 

 

 

[Jessopia74]

What is the voltmeter reading on the dash when idle?

[Raza]

1 hour ago, Jessopia74 said:

What is the voltmeter reading on the dash when idle?

13V at 900 rpm to 14 V with more throtttle

[Raza]

4 hours ago, cam.in.head said:

under the rocker cover you will see all the studs coming up that  the arms fit on. inbeteeen some of them there are plugs inserted into the oil gallery. its not common at all but i have seen a head where one had popped out leaving a hole.

its a long shot and ive only ever seen it once. 

BUT

the fact that you are not getting any oil when you spin the pump with a drill sort of suggests your worse suspicion of suction pipe air leak.   as i said ,oil comes up the suction pipe and straight to the pump first. then to the oil filter. you should see it pump out. try the drill trick with the other cover on .this takes the releif valve out of the equasion..

 

maybe the problem is with those plugs on the head because the cam was completely worn out (strange how the engine worked).  the difference between the cam lobes was 3-4.5 mm .

Now i have new cam.

And that mixing of oil with small bubbles of air in the pump can be a sign of suction pipe?..... It seems that I have all the problems that can be (

 

[cam.in.head]

easy enough to check the plugs in the head.but ....

yours will be no doubt all present . i only mentioned it because i have had it happen once. the syptoms were very low oil pressure at idle..

basically any air leaks before the pump or leaks or wear after the pump can cause low idle pressure. silly question to ask now but i assume you are using 20w or 15w oil ?   nothing thinner .

[Raza]

now oil is mineral 15w 40 ,because I read that engine is not  made for sintetic or multigrade oil

Edited April 17, 2023 by Raza

[cam.in.head]

15w/40 is fine. although 20w/50 will help a little. 

[Raza]

tomorrow the engine will probably go out of the car due to removing the crankcase and suction pipe make tight. Hope that will be 🎱

[cam.in.head]

its a big hassle i know but you will know then ?

good luck hope you find something. 

 

[Raza]

one screw is not properly tightened of suction pipe, now drain the oil and try turning the pump with a drill to see if it still creates air bubbles and will make update what happens

[611]

1 hour ago, Raza said:

one screw is not properly tightened of suction pipe, now drain the oil and try turning the pump with a drill to see if it still creates air bubbles and will make update what happens

Sounds like you might be getting there. I never realised the suction pipe had a gasket until i rebuilt my new engine 🙂

[Raza]

no more small air bubbles when I turn the pump with the drill, I hope to start the engine today