Oil flow

[johng]

If I run my engine without the valve cover how much oil should come out of the push rod. A dribble or a jet

 

[Oneball]

You’ll get oil running down the rockers and splashed around. You won’t get a jet squirting all over the place.

 

[johng]

So I have a jet from 1pushrod does this mean I've got a problem with the hydraulic tappet. I've just replaced all of them because I had a tappet noise. This is my V6 boat engine by the way

 

[Oneball]

Is this with the engine actually running or are you priming it with a drill?

 

[Roscobbc]

Depends perhaps on the oiling system - on my BBC engine with high volumn oil pump it oiling priority is the rockers initially - then mains and lower part of engine.
On the small block its the mains that get the oil first - presumably that apoplies to V6 too?
SBC priority main oiling
In a priority main oiling system, the oil from the engine's primary oil gallery is supplied first to the main bearings and then to the cam, lifters and top end. ... A steady supply of fresh, clean oil helps to keep the temperatures down and greatly increases the longevity of the bearings and associated components
Its impossible on mine to run the engine without the valve covers on mine - the oil jets go everywhere - having said that I've seen other V8 engines where you can run them at idle without too much mess....

 

[Oneball]

The pre Vortec small block isn’t priority mains either. But I’m guessing it’s a Vortec V6 here, not sure about those.

 

[Chuffer]

Just flying kites here , but being a marine installation is the oil pressure and pumping system different to a car as it has to cope with extreme pitch and role at sea .

 

[johng]

Well problem not fixed, but tried lots of things so hopefully someone can come up with a possible answer to my problem, as I'm running out of ideas!
The engine is a 2004 Vortec. According to my manual the oil is supplied directly to the main bearings, big ends, cam and the lifter gallery. Oil is then pumped through a metering valve in each lifter up the push rods to the valve gear. I've got one pushrod that squirts loads of oil, a couple that don't seem to have any oil coming out of them and the rest have a small amount of oil (this is all at tickover).
At the end of last year the engine developed a tappety noise from the lh bank of cylinders. We took the intake manifold off and found the spring clip from one of the lifters was hanging around it's pushrod. The pushrod itself was a slightly dented. We checked all the lifters and a couple were stuck so we freed them off and replaced the one that had lost it's clip, put the engine back together and the tappety noise had shifted to the rh bank!! We stripped the engine down again, replaced all the lifters with a new set (and replaced the dented pushrod) put it back together and started it up today. The noise was still there on the rh side. At this point we took off the valve covers to try and see which valve was giving the problem and found the strange variation in oil flow. I also put a screwdriver on each rocker and listened, they all sounded the same. Then I tried removing the plugs and turning the engine over to feel for looseness in the rockers. On the vortec head there is no way to adjust the valves, you just torque up the rocker and let the lifter take up the slack. None of the rockers felt loose. When the valves are closed you can move the rockers side to side a bit but not up and down. Also you can rotate the pushrods but not move them.
I'm thinking I might have an oil flow problem to the lifters because of the variation in oil flow (we did get sea water in the engine oil a couple of years ago so this could have caused a blockage somewhere) and I'm thinking of trying some flushing oil to see if it can be cleared. However, I'm starting to think that the tapping noise is not the lifters. what else could it be? Piston slap? Small end bearing?

 

[Oneball]

Have you got an oil pressure gauge?

is there any order to the push rods that have oil and those that don’t.

maybe the original problem with the tappets wasn’t the problem but a symptom. Maybe you’ve spun a cam bearing or have blocked oilways and the tappets were starved of oil.

 

[johng]

Oil pressure is around 40psi at tickover and a bit more as you rev it. No obvious order to the push rods although the one with lots of oil is 2nd from the front of the engine and 2 with no oil are 4th and 5th from the front

 

[Chuffer]

If some push rods have oil through , some none , and one "squiring a lot " I would surmise that the bores in some rods are blocked thus shoving more oil up a clear one . No telling what the sea water ingress has done but salt water corrosion might be an issue if it washed oil out or `Hydrauliced ` something .
When I pre loaded all my lifters , I took all the rods out and inspected for wear and checked all the bores were clear before oiling them up and refitting .

 

[johng]

I should have said, I removed the rods that had no oil flow and looked through them, they were clear. I also tried swapping the rod with lots of oil and one with a little bit of oil coming out. The large amount of oil flow stayed with the same valve not with the rod. If there is an oil blockage it must be within the lifters or the lifter gallery. As the lifters are new, my guess is that it's in the gallery. Actually I suppose it could be that the holes in the rockers are blocked, I didn't check that.

 

[Chuffer]

Back to the drawing board then !

 

[Oneball]

Rockers worn so the hole is never open?

 

[Forrest Gump]

Would the amount of oil emerging at the rocker actually have any bearing on the correct operation of the lifter though?
The puzzling thing to me is that you couldn’t pinpoint the noisy tappet with “screwdriver listening”

 

[Roscobbc]

Question - the pushrod that is 'pumping' loads of oil - where is that located in relation to a numbered cam bearing and/or main bearing journal? - wonder is there is a significant blockage somewhere in one of the oil galleries causing an effective high pressure diversion of oil thru' that pushrod - next worry is that if there is a commensurate reduction in oil pressure 'further down the line'.......

 

[johng]

Rockers worn so the hole is never open?

I guess that's possible and fairly easy to check

 

[johng]

Would the amount of oil emerging at the rocker actually have any bearing on the correct operation of the lifter though?
The puzzling thing to me is that you couldn’t pinpoint the noisy tappet with “screwdriver listening”

Well presumably if there is no oil coming up the pushrod, then none is getting to the lifter, but in that case why can't I hear or feel any slack at the rocker? I agree with you the lack of noise through the screwdriver suggests to me that the lifters are all working. So what is the noise? By the way I checked the exhaust manifold bolts and they were all the correct torque.

 

[johng]

Question - the pushrod that is 'pumping' loads of oil - where is that located in relation to a numbered cam bearing and/or main bearing journal? - wonder is there is a significant blockage somewhere in one of the oil galleries causing an effective high pressure diversion of oil thru' that pushrod - next worry is that if there is a commensurate reduction in oil pressure 'further down the line'.......

It's the second valve from the front of the engine. Not knowing what else to try I think I'm going to have a go with some flushing oil or additive. Anyone got any experience with these?

 

[Forrest Gump]

What you really want to do is move the high flowing lifter to another location to see if it does the same.....hope you’ve got a good supply of intake manifold gaskets that’ll tell you lifter or oil gallery issue