Red_bull

Hello guys,

As you might seen in an other topic i rebuild a engine which had problems with oil pressure. Rebuild it again and still have oil pressure problems.

Somewhere i picked up that a cvh head has a oil pressure regulator in the head. Is this true? If so where is this thing located?

Really hope somebody got the answer for me!

haz87

Dont know where you read that but they do not have a 'regulator' in the head at all.
The galleries/brass bushes essentially create flow restrictions thus pressure but these are cast/pressed and dont wear or move etc.

Did you change your oil pump when building this refreshed engine?

Red_bull

It came from a company that i contacted at first to do my engine, but went to another later on.

Also all the metal plates under the rockcovers are in place; The brass inserts are there; My camshaft has the ball on the end;

On the first rebuild a used a shit oil pump; After some running i changed it for a different one as oil pressure was low; Changed it later for a new burton one and ran about 4000 kilometers with it.

Now i rebuild the engine again and used the burton one again. It has been visually checked by my engine rebuild shop and said to be ok. We didn't measure it, but no big wear was seen.

I'm thinking of buying again a fresh oil pump, but when i came to burton webpage it shows two oil pumps (old and new one).

What happend if i have the new one fitted to an old bottom end? I also mailed this to Burton Power, so hope to get their answer aswel!

haz87

You can't fit a pre 86 pump to post 86 crank and vice versa

Red_bull

Thanks i also got that back from Burton!

I'm so fucking clueless on this freaking engine ((

haz87

Personally i wouldnt have re-used the pump, CVH pumps arent expensive. Who built it this time around? Yourself or the same builder from last time? Or someone completely new?

Red_bull

Someone completly new as i moved to another city. Also this was why i asked the question of the two diffent pumps cause i'm gonna put a new one on. I got the answer now, so i will order a new pump today aswell. If that didn't solve it the turbo goes out. i don't want to change two things at the same time as i don't know what caused the problem then!

haz87

The problem is, if it was your pump, then you've now done the damage to the bearings etc.
So fit a new pump but it will still read low due to bearings being screwed.

By doing half a job you've essentially created a viscous circle. Dont mean that to sound horrible, its just the unfortunate thing when building engines on a budget/improperly.

haz87

If you think its the turbo, just take the turbo out the equation.
Remove the turbo oil feed and block it off and see what your hot idle pressure sits at (make sure the turbo wheel does not turn as it will be dry obviously).

Takes 2 minutes to do (plus getting the engine to operating temp) and will prove if the turbo is influencing massively or not

Fraggle...

iTrader: (1)

Did your builder check the crank at the point it engages with the pump?

Mine was so worn it was "clipping" the pump gear , not actually driving it, thus low oil pressure.. could see the scoring, pump gears were erm worn an all!!

The oil pressure switch is located at back of the "block" on the left if looking at engine from front, might pay to chect the switch(exchange it), take the bronze t-piece out, flush it through also CHECK the wiring continuity to the switch, and tbh all the way up the loom...check turbo oil supply line too....could also try an aftermarket gauge to be sure it aint the OE one Telling porkies.

Red_bull

@Haz87 I don't think the bearings are screwed mate. I ran the engine from cold oil to warm exactly onces! also this was with oil pressure not with nothing. I'm on 0.7 bar during idle, so i'm too low but not this 10 minute running will destroy my brand new bearings (Atleast i would say or you think it can go this quick?)

Anyway the new pump is on its way.

But Haz87 how can i get the turbo out of the equation i can't block the compressor wheel or turbine wheel from spinning. So it would mean take out the turbo and then i'm without exhaust. Running it warm without exhaust will mean the neighbourhood kills me!

Or do you have a way to do this?

@Fraggle nice one i will check that, but i'm pretty sure it's not worn there. I'll check it to be sure