Xu9J4 Oil Starvation Prevention (Never Heard That Before?!)

[rodionski 3 1 Cars]

Thanks, that's an interesting read. Now having broken 2 D6C engines with constella design sump baffles, stage2 oil pumps etc during one rallying season, I would really like to concentrate on fighting this problem as I simply no longer have spare cranks to keep rebuilding engines with spun shells - the straight cranks are out of repair sizes and the rest are bent

[wicked 103 3 Cars]

Fit an accusump then; PeterT has good experiences with it.

 

Adding drains to the head is not easy. Fitting a drain that is large enough is impossible imho. *had a good look at the head*

[rodionski 3 1 Cars]

Accusump is on the list of things to do, yes.

I wonder whether anyone has had actual experience running on Peugeot Sport Group N oil control kit for the 306 S16 engine?

The kit is available at Peugeot Sport and offers quite an interesting trap door system in my opinion (compared to the constella system having no trap doors which NEVER can control oil during any rallying events - it can only cope with trackdays without any extensive cornering).

[James504 12]

Personally I have not used one, but from what I have heard the Constella baffle is not the be all and end all.

 

Not knowing the regulations of your rally class, I dont know if these are suitable suggestions.

- As wicked said, fit an accusump or similar device.

- Drysump

- Fit an Xu10j4rs head

 

Spinning shells is not always an oil pressure problem. Tolerance control with only a 2 bolt main cap is never an ideal situation.

[rodionski 3 1 Cars]

Well, I am keen on battling the oil surge on all fronts, so along with a comprehensive baffle/trap door system (thinking about building a similar one to Peugeot Sport Group N or heavily modifying the constella one) and fitting accusump, am I also seeing a need to cure the oil lake in the head.

A dry sump system is unfortunately too expensive.

 

By the way, Peugeot sport also had a similar baffle/trap door system for the XU10J4RS engines, so that is a must (at minimum) in any case.

Edited December 1, 2012 by rodionski

[welshpug 1,621]

I don't think a dry sump costs that much in reality, what does an accusump system cost?

[James504 12]

350-370 usd for the 3qt elec valve model, by the time you add hoses and fittings maybe 450-500usd. It depends how seriously involved you are with the car. By the time you rebuild your 2nd engine dollars spent would be heading towards the cost of a drysump. Are pace the only company who offer an off the shelf kit for the Xu?

Edited December 1, 2012 by James504

[rodionski 3 1 Cars]

In our neck of the woods, roughly USD500-600 for an Accusump system and about USD1500-2000 for a complete Pace system (oil tank, oil catch/breather tank, fittings etc)

[petert 549]

I bought a 1.5Q Moroso accumulator (US$195) along with fittings, hose etc from Summit. So did a friend. It worked out at approx $350 each landed, with heaps of braided hose left over. It's timely bringing back this thread. Here's our experiences from today at Eastern Creek South circuit. It's a new, extremely tight and twisty circuit, specifically designed to destroy XU engines I think.

 

Car 1 (mine): XU10J4, extended pickup, windage tray, deep sump, etc solid lifters

 

Car 2 (Adrian): XU1094, extended pickup, windage tray, deep sump, etc hydraulic lifters

 

Car 1 has the oil pressure idiot light set to 25psi, Car 2 35psi. Adrian had the light coming on repeatedly for lengthy periods, I didn't see a light flash all day. This could mean that Adrian still has >25psi under extreme conditions. I may have had only 30psi. One thing is for sure, the tight and twisty switchbacks didn't allow the 1.5Q accumulator in Adrian's car time to refill between corners, in order to guarantee 35psi. We kept on sticking the boot in all day and both cars finished the day unscathed.

 

Th only other difference between the cars are the solid lifters in my car, which have two restrictors to limit oil to the head.

 

I'll leave it there and you can make up your own minds.

[rodionski 3 1 Cars]

Hey Peter, nice to hear from you!

What did you guys have in terms of baffles in the sump?

 

By the way, the description of the race track you gave sounds all too similar to our rally stages this year - extremely tight and twisty with lots of 90 - 180 degree slow corners after decent straights, demanding extreme braking and sharp turn-ins. XU9J4 killers, proven twice this year

Edited December 2, 2012 by rodionski

[petert 549]

XU10, along with a trap door on the extended, custom oil pump baffle.

[rodionski 3 1 Cars]

No oil drains from the head I assume?

Personally I am leaning towards two alternative options:

 

1. Peugeot Sport XU10J4 Group N baffle setup + accusump + solid lifters + head oilway restrictors + possibly an external oil drain from the head

or 2. Pace drysump setup, possibly with a 4-section to scavenge the head.

[petert 549]

I saw one of Grp N sumps recently. It's a nice bit of kit. The dry sump also has the benefit of unleashing a few extra hp. A 405 over here, recently reported 105kW at the wheels from a Pace equipped XU9J4Z. The only other mods were throttle bodies. A std XU9J4Z does 75-80kW at the wheels.

[rodionski 3 1 Cars]

I agree that the Grp N kit seems to be quite nice, and I actually see why and how it will work during braking/cornering.

One thing that amuses me is the rather complicated bend in the baffle pointing towards the front of the car between the two walls forming the front-center boxed out space. Why go through the hassle of fabricating that?

The only idea i have to explain is that maybe it is intended to collect oil going through the center hole in the stock windage tray and put it directly into the oil pickup boxed out space?

 

Re power gains with the dry sump - yes, while power I seem to have enough (running 45mm Dbilas ITBs with short inlet length, 350cc injectors, aftermarket ECU and ignition, all that goes to the road through a limited slip diff), it is ONE problem that I have - oil surge killing engines one after another.

 

By the way, has anyone had experience with repairing bent cranks and/or restoring worn crank surfaces via sputtering? Several of our machine shops offer both services, but it remains a question for me whether or not such repairs could survive continued 7500 revs..

Edited December 2, 2012 by rodionski

[wicked 103 3 Cars]

.

One thing that amuses me is the rather complicated bend in the baffle pointing towards the front of the car between the two walls forming the front-center boxed out space. Why go through the hassle of fabricating that?

 

For the oil stick maybe??

[rodionski 3 1 Cars]

Emm, not really, I don't think it is intended for the oil level dipstick as it is located a bit more to the right as far as I recall. I also doubt that they would go that length to fabricate these very complicated bends just for the dipstick - far easier to drill a hole

[rodionski 3 1 Cars]

Another related question to everyone - who has actually drilled the head to install an oil drain pipe?

I am currently looking into electrical oil pumps (similar to Mocal) to scavenge the head, have found a decent one for sale in the US, but I am still unsure as to where the head can be drilled..

[petert 549]

One thing that amuses me is the rather complicated bend in the baffle pointing towards the front of the car between the two walls forming the front-center boxed out space. Why go through the hassle of fabricating that?

 

I think that's to catch oil coming back down the filler/breather tube so it doesn't hit the crank.

 

I haven't had experience coating cranks but I do think 1.9L turbo diesel cranks are a better solution.

 

You need to drill in centre of the head at the back. I'll take a pic for you later.

[rodionski 3 1 Cars]

Many thanks Peter, I would really appreciate pictures of where to drill the head!

On a sorry note - I've just returned home after towing the car to the shop with a huge knocking sound, apparently from a yet again spun rod shell, and that's after TWO days since rebuild!

[petert 549]

Do you close and hone the rods during the rebuild process?

[rodionski 3 1 Cars]

Nope, this time they left the rods be. Which was obviously a mistake. Normally the rods are taken out and measured carefully and replaced if showing any defects.

Now that I have quite a collection of 0-shaped rods and scarred cranks, I might as well venture into coating the cranks (at least for non-track engines) and cutting the rod caps and machining the new bottom surfaces in the rods.

[petert 549]

In the picture below, the ideal spots to drill are directly above the top exhaust studs, in the curved section. Ideally, you'd drill four holes, linked to a manifold, draining back to the sump. I wouldn't like to drill larger than 10mm, so probably a 1/4"NPT/BSP thread? Piped back with #10 hose? It wouldn't need a pump, as gravity will do the work.

 

The exhaust cam/buckets definitely run in a bath. Thus there are no oil spray holes in the exhaust tube.

Edited December 3, 2012 by petert

[rodionski 3 1 Cars]

Many many thanks Peter! That actually confirms my imagined places for drilling.

My concern would be however with using an external scavenge pump in one or two of the ports going into the manifold sucking air during heavy cornering - could that inevitably make the system ineffective?

I suppose that it will always be the case due to movement of oil from one side of the head to the other, as well as from the back of the head to the front during heavy braking (thinking about this, in a scenario of a 180 degree right hairpin, there would be heavy braking and then a massive turn right - the oil should run to the inlet cam and then to the left corner of the head - that would definitely leave the drain ports (at least three out of four) hanging dry, wouldn't it? - Maybe then the same set of drains should be drilled above the inlet? But then I figure they should rather be drained by gravity rather than scavenged by pump as on any straights the pump would be sucking air from the inlet side drains)

[James504 12]

High and sustained rpm will test the sprayed layer. It is definatly not recommened. I took part in a rebuild of a detroit diesel 110, which had a flogged out (really flogged out) keyway on the nose of the crank(unobtanium), it was repaired using metal spraing, but its not a bearing surface and not in a high rpm motor. An xud9 crank also has the added advantage of being forged. I wouldn't turn my nose up at a 8v 1.9 crank either. It would make for good economy if you used some forged H or I beam rods. I think sooner or later you will have a standard rod/bolt failure in a competition engine.

 

Peter, any reason for the choice of the 1.5qt tank over the 3? Other than size and or that was the model on special from summit?

[petert 549]

There was no chance of fitting a 3Q model in the engine bay. It would be illegal inside the cabin, unless fully enclosed.

 

Lotus Elises run the 1.5Q model.