Rebuild Thread (Probably)

[Ciaraneng]

Pretty sure the readings are correct or pretty close carerra. It's a brand new gauge and they match another gauge I had that I didn't trust but hoped was wrong. And yes a rebuild, late case but in a van originally fitted with an early case so no DOPS system. In spec crank with new main bearings, cam and cam bearings, tappets. New BW oil pump was fitted with a gasket

Yes, I figured the oil pump refit would be my next move. I have a new cover purchased but I am tempted to combine it with the old pump from my original engine as it seems to be higher volume and a much quality better build than the new pumps.

I have been cleaning it up wit wet and dry.Now I must look up BigBadBob's posts about how to change the pump with the engine in place...

[937carrera]

http://forum.club8090.co.uk/viewtopic.p ... &start=360

Hope you're not too squeamish, Bob's missus was going through the final stages of her cancer at that time

[Ciaraneng]

Thanks Carrera. Can't see much detail on how to replace the pump in BigBadBob76's thread. From what I can tell, the engine bearer will need to come off so I'll need to hold the engine up from beneath while I replace the pump. I'll probably suspend from the top as well until the bearer is back in place (belt and braces and all that).

E D I T: Found it

This looks like the way to go..

silencer off, tin shroud off, support engine, engine bar off, engine cradel off, crank pulley off, water pipes off....

[itchyfeet]

silencer off, tin shroud off, support engine, engine bar off, engine cradel off, crank pulley off, water pipes off....

yep, don't need to lower engine but everything neear pump must come off . I think both BBB and I changed the pump more than once after the first time when you know what you are doing you can do it in 1-2 hours

The dirko HT red sealant in a horse shoe shape both sides seemed to help also. Eventually I o ringed it though.

if you are removing gasket you can fettle pump to zero end float with wet and dry on a flat surface but you need to have the pump out and bolt cover on to ensure it's not grinding on the cover.

http://forum.club8090.co.uk/viewtopic.p ... &start=314" onclick="window.open(this.href);return false;

[Ciaraneng]

Thanks Paul. When you fettled the pump body did you go for a good quality finish or just focus on minimising clearance? I have 400, 800, 1500 and 2400 grit wet & dry so was thinking I might go for the best possible finish on pump housing, cover and gears. Also, I was thinking I might work on the old steel 34mm gear height steel body pump rather than use the new pump body which I think is a 26mm gear height aluminium body pump. The thinking is that I will get 30% more flow per rev and as the temperature rises, the clearance between gear and body should stay the same for the steel pump whereas it will increase for the aluminium body with steel gears. I am calculating an increase in clearance between gears and body of .02mm over 70 Deg C. ((22.5-11.75 um/m)*.026*(80-10)). It makes a bit of a mockery of the .05-.10mm spec for clearance when it increases by .02mm at running temperature.

[itchyfeet]

I'd say finish is not so important.

whats a mockery is you can't buy a gasket under 0.1mm

never seen a steel pump body got a pic?

[Ciaraneng]

Here are some photos of the steel pump Paul.

[Ciaraneng]

I put in the Mann filter and a Halfords 20W50 and to see if pressure would increase and so that when I replace the pump I would know if an improvement was down to the oil and filter or the pump. It mad a difference when cold but no major difference when hot

Cold:
Tick-over @ 800 rpm: 4 Bar (58psi) (Previously 1.5 Bar (24psi))
2000 rpm: 4.2 Bar (61psi) (Previously 4 Bar (58psi))

Hot (80 Deg C)
Tick-over @ 800 rpm: 0.25 Bar (5psi) (Previously the same)
2000 rpm: 1 Bar (15psi) (Previously 0.5 Bar (10psi))

The plan for next weekend is to change the pump out for a reconditioned old pump. I used a range of wet and dry grit paper to clean up the face of the pump and the new cover. From the way the new cover cleaned up, it looks like it was slightly concave so it was worth doing.


By the time I was finished I had interference between the gears and the cover but when I added a cover gasket I have clearance. I'm torn between using a gasket and fettling the gears back and using dirko...

[itchyfeet]

I'm torn between using a gasket and fettling the gears back and using curil T...

fixed that for you.

USA stamped on that cover plate.

Never seen a pump like that are you 100% sure it's ferrous metal?

[Ciaraneng]

I'm torn between using a gasket and fettling the gears back and using curil T...

fixed that for you.

Thanks Paul

USA stamped on that cover plate.

Never seen a pump like that are you 100% sure it's ferrous metal?

I wasn't but I am now. It's strongly magnetic.

Wrong cam, wrong lifters, wrong carb... Why not wrong pump?

Were all original T25 oil pumps aluminium?

[Ciaraneng]

Now that I think about it, the flat cover plate is so that it doesn't have to be ground back to avoid the engine bearer. I might clean that one up instead of using the new one (that I spent over an hour fettling ).

[itchyfeet]

Melling oil pump I'm told.

[Ciaraneng]

Melling oil pump I'm told.

Hmmmm, the Melling reviews on the samba are not exactly stellar...
I might give it a go and go for a Marco Mansi pump if I don't get sufficient pressure.

[937carrera]

Have a read here then

https://shoptalkforums.com/viewtopic.php?f=37&t=109294

[itchyfeet]

Yes its a melling like Jason said, dont use it whatever you do, its terrible when the engine gets hot, the case grows and the pump body doesn’t

FB has it's uses!!!...I posted your pics on a dedicated WBX group.

Marco builds turbo WBX for bug racing so he knows his onions.