Temp and Pressure Gauges

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KINGPRAWN
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Re: Temp and Pressure Gauges

Post by KINGPRAWN »

tencentlife wrote:
Tencent builds wbx's over in The United States in America. He modifies them, and will only guarantee them if an oil cooler is fitted. He modifies the pressure relief valve to improve oil circulation (iirc)

I do build upgraded wbx's that make about 20% more power than stock (35% with my tuned exhaust) and in the process I tighten main and rod bearing clearances and blueprint the "feck" out of the oil pump (3 o-rings!) to guarantee excellent lubrication with lighter-grade oils ( I would forbid use of 20w50 if I could! But none of my customers use it anyway). As such I DO NOT require use of my external oil cooler kit to get a warranty, all my engines have a 1yr/12k miles warranty. But I double the warranty with the addition of one of my external oil coolers as an incentive to use one, because by putting a cap on peak on oil temperatures it allows safe use of even lighter more efficient oils and extended drain intervals to save money and resources. Just wanted to clear that up...
Mr TENCENT' can I run this by you.... My DJ low miles (recon motor) has an oil pressure when cold of 4.5 bar but as soon as the oil temp reaches 80 deg the pressure at idle drops to almost zero! And whilst driving I get 1 bar @ 2k .. 1.5 @ 3k ... 2 bar @ 4 k ( you get the pattern). I use no oil, not rattles, clanks or anything bad! Oil temp never goes much if ever above 80 deg And it goes REALLY well!!!
Oil pump??? Or worse!!!
in too deep to quit now....

bootie3367
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Re: Temp and Pressure Gauges

Post by bootie3367 »

Just like to re-iterate... a very informative post and one that has been marked for my attention in the coming months!

Cheers :ok
'89 Westy Joker Hitop
1.6TD JX engine

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Re: Temp and Pressure Gauges

Post by silverbullet »

KINGPRAWN wrote: Mr TENCENT' can I run this by you.... My DJ low miles (recon motor) has an oil pressure when cold of 4.5 bar but as soon as the oil temp reaches 80 deg the pressure at idle drops to almost zero! And whilst driving I get 1 bar @ 2k .. 1.5 @ 3k ... 2 bar @ 4 k ( you get the pattern). I use no oil, not rattles, clanks or anything bad! Oil temp never goes much if ever above 80 deg And it goes REALLY well!!!
Oil pump??? Or worse!!!

FWIW, there are re-con, refurb and rebuilt motors. None are clearly defined terms in the motor trade! I have found that the WBX Elring gasket sets have a stupid thick gasket for the oil pump end cover, over 3 times what it should be compared to OEM. This means excess blow-by across the oil pump gears and poor pumping pressure at low rpm. I have also O-ringed pumps but only use the one at the mo, will be upgrading that to 2 minimum next time.

1 bar at 2k is not enough. It should leap up once off idle, The engine won't last long with these sort of low pressures.

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orcecaveman
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Re: Temp and Pressure Gauges

Post by orcecaveman »

KP, Are you sure your gauges are reding correct, cause you also said that your temperature guage dosen't register very high?

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Re: Temp and Pressure Gauges

Post by tencentlife »

What silverbullet said, for the most part, but I can't echo the last part. It's lower OP than I would be comfy with but no one can predict with such certainty that it won't live a normal life with those OP's, there are thousands of wbx's running around with similar, yet instances of bearing failures are fairly small give the number and age of the engines in use. The question is what are they when the OT hits 100? Probably a lot lower. If it's still under warranty you certainly have grounds for complaint to the builder, he should at minimum refit the oil pump with closer axial clearance because that's likely to be half the trouble right there.

KINGPRAWN
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Re: Temp and Pressure Gauges

Post by KINGPRAWN »

orcecaveman wrote:KP, Are you sure your gauges are reding correct, cause you also said that your temperature guage dosen't register very high?
Thanks but yes bought a proper op gauge to check and its the same!! ... Temp was sorted with a new sender!
in too deep to quit now....

KINGPRAWN
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Re: Temp and Pressure Gauges

Post by KINGPRAWN »

tencentlife wrote:What silverbullet said, for the most part, but I can't echo the last part. It's lower OP than I would be comfy with but no one can predict with such certainty that it won't live a normal life with those OP's, there are thousands of wbx's running around with similar, yet instances of bearing failures are fairly small give the number and age of the engines in use. The question is what are they when the OT hits 100? Probably a lot lower. If it's still under warranty you certainly have grounds for complaint to the builder, he should at minimum refit the oil pump with closer axial clearance because that's likely to be half the trouble right there.
Well I've been blissfully ignorant except got the buzzer on a long run if I push it along for a while, but its been going along for the last 7 years!!
in too deep to quit now....

KINGPRAWN
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Re: Temp and Pressure Gauges

Post by KINGPRAWN »

silverbullet wrote:
KINGPRAWN wrote: Mr TENCENT' can I run this by you.... My DJ low miles (recon motor) has an oil pressure when cold of 4.5 bar but as soon as the oil temp reaches 80 deg the pressure at idle drops to almost zero! And whilst driving I get 1 bar @ 2k .. 1.5 @ 3k ... 2 bar @ 4 k ( you get the pattern). I use no oil, not rattles, clanks or anything bad! Oil temp never goes much if ever above 80 deg And it goes REALLY well!!!
Oil pump??? Or worse!!!

FWIW, there are re-con, refurb and rebuilt motors. None are clearly defined terms in the motor trade! I have found that the WBX Elring gasket sets have a stupid thick gasket for the oil pump end cover, over 3 times what it should be compared to OEM. This means excess blow-by across the oil pump gears and poor pumping pressure at low rpm. I have also O-ringed pumps but only use the one at the mo, will be upgrading that to 2 minimum next time.

1 bar at 2k is not enough. It should leap up once off idle, The engine won't last long with these sort of low pressures.
So if I were to get a new pump there's a good chance of an improvement?
I'm currently using Fuchs 15/40 and two bottles of STP treatment... How heavy an oil will my tappers cope with??
in too deep to quit now....

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Re: Temp and Pressure Gauges

Post by silverbullet »

Heavy oil is not a good thing! Recommended grade is now 5W40 semi-synthetic (Quantum Sapphire?), meets the relevant VW spec for the wbx engine. Aidan can comment further as he's using it.

What you need to do is check that your OP gauge is reading correctly (get engine checked against a calibrated workshop gauge) and if all's well, then do a minimum spend exercise on the oil pump. If the pump gear end clearances check out with a straight edge (0.05mm feeler gauge max IIRC) then you'll only need a new gasket (should be thinner than greaseproof paper) and 4 new sealing nuts. If that doesn't do the trick, then pull the pump and replace.

Having said all that, whoever built the motor needs to answer a few questions before you spend any more money or invalidate any warranty.

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Re: Temp and Pressure Gauges

Post by tencentlife »

You don't need a new anything, you need to make the gear axial clearance .003" or less. More than that and the pump will have too much "slip" when the oil is a operating temp and it won't raise consistent pressure. Use no cover gasket (this is actually the specified treatment for the wbx pumps). This is elementary stuff.

Unless it has been chewing on scraps of steel, there is only one place on these oil pumps where routine wear necessitates replacement. That is the fit of the driven gear in its bearing bore (which would have had a bronze bushing if VW wasn't so damn cheap). It can be assessed by rocking the driven gear in the vertical axis, rocking more than about 3 thou indicates a worn pump body.

The cover is a separate item where it is easy to see the wear and as easy to remedy it.

Having said all that, whoever built the motor needs to answer a few questions before you spend any more money or invalidate any warranty.
He said it's been 7 years, he's ages out of warranty, the builder has no responsibility. For a warranty to be of any value, the engine has to get used during the warrnaty period (that's why it's typically X-miles/X- months, whichever comes first. People get a fresh engine, don't use it, and expect the builder to have perpetual liability, which is absurd and unfair. You must use the engine enough during the warranty period to prove out defects. If you wait, you lose, and that's your tough luck, not the builder's.

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Re: Temp and Pressure Gauges

Post by silverbullet »

:oops: I missed the 7-year bit! Do as Stan says, check it out and see what's what. It's an easy enough fix if you know how to work clean on an in-situ job (not one for a windy day outside!)

PS what is the actual mileage on this "re-con" engine? If it was a recycled special then it might contain anything!

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Re: Temp and Pressure Gauges

Post by orcecaveman »

Im sure there would be no warranty anyway if its had STP oil additve added. If it needs that to keep the pressure up, im sure it would suggest something is "feck" / worn out.

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Re: Temp and Pressure Gauges

Post by KINGPRAWN »

orcecaveman wrote:Im sure there would be no warranty anyway if its had STP oil additve added. If it needs that to keep the pressure up, im sure it would suggest something is "feck" / worn out.
I'd almost be happier if it ran like a bag of "pooh"... But it's all hunky dory but with no pressure!!!
in too deep to quit now....

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Re: Temp and Pressure Gauges

Post by silverbullet »

If it's really got naff all o.p. at idle then the BOD should be going off, likewise if it's below par at 2k it should buzz. Time to check your gauge, sender, switches, wiring, instrument earths...the gauge could be a red herring!

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Re: Temp and Pressure Gauges

Post by silverbullet »

Useful Audi part numbers for combined oil pressure sender/switch unit with 2 terminals, M10x1 thread:

035 919 561 0-5 bar, 0.3 bar switch.

035 919 561A 0-5 bar, 1.8 bar switch.

These replace 056 919 081 C and E respectively

I was checking 035 919 521B oil temp sender 0-180 deg C :shock: It fits direct into the 5-cyl oil pump with M22 x1.5 thread, highest possible oil temps on a n/a engine are at the pump outlet (unless the bearings fail!) so could be why it has to read so high?

Maybe I can fit one to the wbx and see what results...

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