Volvo Supercharger (KAD) servicing

BruceK

BruceK

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When checking my intercoolers (CACs) as part of maintenance I noticed some super charger oil in. Sure enough the SC had very little oil left in it's reservoir after a season. I know servicing KAD SC's is very limited but can the seals and bearings which ever it is be serviced / replaced? If so is this a general engineering shop or is a specialist required and if so any recommendations.

Thanks in advance
 
There’s been huge debates on here regarding constant / excessive running if the Volvo KAD SC s .
I recall someone commenting on the whine in the background on one of your vids .

I have warned about bearing / seal failure .

I saw in a hand book something about just using them to get up on the plane and advance the rpm enough for the turbo to take over ...so 30/40 seconds running .
I recall PeteM grilling me and posting end less copies of pages of VP to argue it’s OK using it , because it does not specifically say don’t .
Additionally folks x referring to Mercs “ compressor “ and other quasi arguments for the V P - SC Continuously being used .

They are different ,animals .Theres a thread on here somewhere .

Any how you should be able to replace the oil seal and bearing(s) .

In the mean time replenish the oil and adapt the boat use away from constant running .

Another one the power steering pumps on cars aren't designed for constant running , they overheat and pop seals too .
Folks holding the steering right over on full lock while stationary regularly = bust PAS seals + leak or blown seals in the rack prematurely. Having said that some PAS pumps are water cooled nowadays so are more durable constant running .
 
Without listening to it / them ?
Or seeing them stripped down ....if the vane bearing (s) have worn the vanes over time might have facetted as the in-effect started to wobble with too much axial play .
They will have worn together maintaining enough air tightness to kinda work , but eventually as the wobble increases the rpm and air pressure decrease .

Depending on how far on the wear is .....when reassembled with new bearings zero axial play ( or within OEM tolerance) because of the loss of metal due to faceting there may be now a air gap and resultant loss of compression.

So it might be better to think new unit .Depends on the facet wear ?
 
I'm in the camp of dont run them continuously if you can avoid it. However, you are quite wrong in saying they cant be held in continuous use, quite simply because the Ogura design actually made them to be used in continuous use delivering a constant 1.8 pressure ratio and they are fitted with a clutch to prevent parasitic drag after the turbo spools up. The fact that the engine design calls for a smaller turbo with SC to bypass turbo lag getting out the hole does not detract from them being capable of continuous use.

I take your point on vane wear. However I am not overly concerned at this point. It has taken an entire season to lose 80ml of oil. I'd hardly call the bearings shot, more like due for replacement
 
Engine oil and compressor oil are very easily distinguishable, both in colour and viscosity

Edit
The compressor oil had formed a small pool in the casing under the core. A couple teaspoons full. Not in the core itself which is mildly sooty and black.
 
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Fair enough - so its clean oil and not black engine oil.
The reason I ask is a little oil from the turbocharger is quite common an often occurs after extended slow running.

Could it be the wrong supercharger oil was used last time it was changed ?
 
Clean, "thin", with a mild reddish tinge yes. I am confident it is the correct oil. The only caveat I will place is I have habitually topped it up whereas the book of words says you should drain and replace. The oil on the dipstick has always been perfectly fine though.

Keypart
 
Sorry just trying to rule out other possibilities
Don't think I have heard of this issue previously .
 
No need for apologies, no offence whatsoever was ever taken. I am open to all and every suggestion. If I can avoid having to crack this thing open only to be disappointed to find I've been a dumbass I'm game. Sadly I think some seal or other either on the bearing or whatever sealing seal there is, is tired. Loosing some oil is expected and by design, the book of words says to check and fill at quite a high frequency, something like every 10 hours (yet who does) but I will need to consult it again before you can quote me on that. All but emptying a reservoir over a season though, not so fine.
 
Now I am going to have to check my supercharger oil as I have never considered oil loss to be a risk.
 
Thats your best joke ever Roy:D

Any words of wisdom re SC overhaul? We can discuss it over a beer or two on yours. (y)
 
Im fairly sure Volvopaul indicated the supercharger oil could be left in 1000 engine hours providing the oil remained a good colour.
That also implies oil consumption is not normal.
As you are not describing a failure other than the oil leak I would hope the supercharger may be repaired by a specialist . As a new purchase a supercharger appears to be a very expensive item .
 
MartynG said:
Google found a possibly useful company
Powerhouse Automotive | Supercharger Rebuild
.
Click to expand...
Speaking to your SC specialist (but who has no direct expertise with Oguras) he believes the seal behind the bearing is leaking but that the bearing is resined in and there is no way to remove the bearing without breaking the case. He's happy to have a look at mine and evaluate. If I have to buy another it may be worth the punt to pass the old one to him for a kick about as he's relatively local. In the meantime my search for answers continues. There is a company in Canada that sells a bearing rebuild kit for them so there must be a means known to the insiders. If only I could kick their door down and get some answers
 
:cautious: I see you've verified my membership to the Stupids Club. I worked hard for that you know, wasn't an honorary bestowal. Damn dipstick giving me the silent treatment no matter how hard I shout at it.

;) It's wet but below min.
 
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