Stone Stomper causing soot stains?

[KeithB]

In an earlier post I mentioned that my 200 series had blown up its motor, presumably due to dust ingress. So we now have a new crate motor in with a Patrol Dokta stainless steel air box and a Donaldson cyclone prefilter on top of the Airmax Snorkel.

We left Sydney about six weeks ago after running the motor in, towing a 2,500kg caravan in a roundabout route from Sydney to Adelaide. The motor now has about 7,000km on it an, is running beautifully and burns no oil. We usually sit on 100kph at 1,800rpm in fifth gear with the transmission locked.

I have a Stone Stomper on the back of the tow which has a flap that comes down behind the exhaust outlet at slower speeds. Below is a shot from the SS website, which looks like my setup.  I have been noticing a whole load of black oily soot on the tailgate around the exhaust.

https://images.app.goo.gl/7cwP7ynQSzHknGbz6

Is this the fault of the Stone Stone Stomper or do I have another engine problem?
Do other Stone Stomper users have this problem?

Keith

[gronk]

I run a stomper on my 09 model and apart from the flap getting black, I have no evidence of soot or staining on the car !

[xcvator]

Can you lift the flap up semi permanent, clean off the soot and see what happens ?

[Bird]

Any photos of your actual setup and the soot? how much is there?

What did the dealer say?

[GeoffA]

If you're towing at 100kph I'd guess that you're on sealed roads.
The engine may only be doing 1800rpm, but it will still be wanting plenty of air.
If that's the case, do you really need the Donaldson? They're really meant for slower going.
I reckon I'd be trying it without the Donaldson first up. Do you have the Airmax ram head with you?

 

[glenm64]

I got the local exhaust guy to put a bend away from my stone Stomper curtain. Wasnt worried about soot etc, more the heat.
My Dmax uses no oil, and I still get some soot. No DPF or EGR on mine though.

Sent from my SM-T810 using Tapatalk

[GGV8Cruza]

I have the same on my 200 with a new engine, not bad but it does show up more when the camper is attached.

GG

[silverfox1111]

Do you have a catch can fitted to the motor? When the car is working hard, as in towing, I get a lot more oil in my catch can caused by the increased blow by. If yours doesn't have one fitted, you could possibly be getting more of this oil vapour passing through the motor causing the soot.
Silverfox

[Foss]

I have soot marks on the canvas flap that lifts up with the wind, but get nothing on any of the bodywork. Mine is a LC200 non DPF - hence the black soot. Quick question though - how far from the bumper is the Stonestomper bar that is attached to the tow hitch? Could it be that yours is further back thus creating a larger gap which in turn might be letting exhaust gases/soot through there? I have mine as close as possible without it touching and get nothing on the paintwork.  Just a thought.

[doc evil]

Might be more of the disruption of the flow from the exhaust and air flow around the exhaust.

The mighty patrol has the exhaust behind the mudguard yet the guard and flap are always sooty. Bit hard to see, but the discolouration is there.

[KeithB]

Thanks for all of your replies.

My soot is mostly over the left side of the lower sill panel with a fair bit about 400mm up the tailgate. I cleaned it up last night, so I can't show a picture.

Foss: The bar is mounted just in front of the coupling, down low, in order to clear the clamps for the spare wheels on the back. This puts it well back from the bodywork, which may be part of the problem. In answer to a question regarding mud getting up onto the caravan, Christian at Stone Stomper suggested bending the bar forward to minimise the gap between it and the bodywork. I'll get started on that.

Silverfox:  I do have a catch can fitted but no DPF.

Geoff: Unfortunately I don't have the old ram head with me. I am hoping that the better flow through the new air box will compensate for any loss through the Donaldson Cyclone. As well as highway work, we have also been doing a lot of unsealed back roads at 40-60kph.

Bird:  I'll post some photos when the soot comes back.

Xcavator: I have a couple of metres of shock cord. I'll see if I can follow your suggestion and secure the flap up and out of the way.

The soot is a nuisance. My main worry was possibly something wrong with the engine. I had soot last time, before my old engine blew up. Let's hope it's coincidence.

Thanks again.
Keith

[Bird]

I am hoping that the better flow through the new air box will compensate for any loss through the Donaldson Cyclone.

The air has to get to the airbox.
When I swapped turbos, we tried the 12in Donaldson on my GU with Safari snorkel versus the stock ram head and the figures were different (not airflow but kw/nm)
I find it surpising that some Yotas come with the (what looks to me to be small) 'mushroom' head as factory

[wetduck]

a stab in the dark here.

I have an old tractor,  when I lug the motor smoke pours out of the exhaust. Perhaps this might be similar to your 200 towing 2.5t @1800rpm in 5th gear?

My daily drive is a VDJ79 single turbo version of your motor but the manual gearing puts me at about 2400rpm @ 100kmh in 5th.

cheers Leo

[KeithB]

a stab in the dark here.

I have an old tractor,  when I lug the motor smoke pours out of the exhaust. Perhaps this might be similar to your 200 towing 2.5t @1800rpm in 5th gear?

My daily drive is a VDJ79 single turbo version of your motor but the manual gearing puts me at about 2400rpm @ 100kmh in 5th.

cheers Leo

Leo, mine's a six speed auto and the manual says to tow in 5th. I have a transmission lockup to the engine is not working too hard. I get about 20- 21 l/100 on a flat road at 100kph. So the engine is just loping along.
Many thanks
Keith

[MrCruza]

I just got a SS for use on my new van. Previously had one on the Aussie Swag camper. The new one for the 200 has a notch cut out of the bottom of the skirt, presumably to cater for exhaust gases. No problems with soot on the car so far.

[gronk]

I've bent mine to suit the rear of the 4wd......and I also ran a string line from rear of tyre up parallel to the bottom of the mudflap to make sure no stones get over the top of the flap !!

[Bookleaf]

Not a 200 but a MUX for me.
SS advised I get a turn-down for the exhaust to direct the gasses and soot towards the ground and not straight out the back, so reducing the incidence of soot and heat on the skirt.
I have done this but still get some soot deposits.
At even slow seeds I think the skirt blows up and almost out the way of the tailpipe, so is not in the way of the exhaust as much as it would seem when stationary.

I think all diesel motors give off some soot, even if it can not be seen.  When accumulated and it builds up, it becomes apparent.

[HOGES86]

All diesels will produce soot, but i am worried about that fact that it is oily. Was the exhaust cleaned out prior to the new motor being fitted? It could be just residual oil in the exhaust being blown out. Soot is just caused by diesel not being fully burnt (overfuelling/not enough inlet air to some degree). A blocked air cleaner will make this worse.

A compression test should tell you if you have the same issue. The 200's were notorious for dusting the engines due to crap airboxes. A good snorkel is a must with these engines. A good ram head for the snorkel will also help. The Donaldson style are good for farm use with a heck of a lot of dust/seeds etc as they have a pre cleaning function, but a ram head is better for highway use.

The stone stomper may also be interfering with the exhaust flow, but a bent tip, as per Glenm64's comment, should help direct the soot away.

[KeithB]

All diesels will produce soot, but i am worried about that fact that it is oily. Was the exhaust cleaned out prior to the new motor being fitted? It could be just residual oil in the exhaust being blown out. Soot is just caused by diesel not being fully burnt (overfuelling/not enough inlet air to some degree). A blocked air cleaner will make this worse.

I cleaned all the muck off the back of the car and it was not oily as I had first thought. Just soot.  I have bent the SS bar forward so that there is very little clearance between it and the rear sill panel. We'll see if that does the trick after we are back on the road tomorrow. The exhaust pipe does direct the gas slightly downward, but not much.

I think I saw an independent test that claimed that the Donaldson reduced the 0-100 time by less than half a second. I am hoping that the improved flow through the aftermarket airbox will help offset that.

Many thanks.
Keith

[gronk]

I am hoping that the improved flow through the aftermarket airbox will help offset that.

Many thanks.
Keith

Have you in fact got improved airflow ?

[KeithB]

Have you in fact got improved airflow ?

Gronk I can't say that the new airbox gives better airflow, although the supplier says it does. Dunno.
Anyhow, after bending the SS bars forward to almost touch the rear sill panel, we did a bit of heavy work yesterday towing the rig in first and second gears up the hills out of Rapid Bay, south of Adelaide plus a lot of other hilly stuff. There are no soot stains above the SS bar any more, but plenty below it. I guess I'll have to live with that.
Thanks for all the suggestions and advice.
Keith

[gronk]

Gronk I can't say that the new airbox gives better airflow, although the supplier says it does. Dunno.
Anyhow, after bending the SS bars forward to almost touch the rear sill panel, we did a bit of heavy work yesterday towing the rig in first and second gears up the hills out of Rapid Bay, south of Adelaide plus a lot of other hilly stuff. There are no soot stains above the SS bar any more, but plenty below it. I guess I'll have to live with that.
Thanks for all the suggestions and advice.
Keith

Yeh, the flap on mine gets really black behind the exhaust...so there is soot coming out the exhaust, but flap on or off, I never notice any on the back of the 4wd..

[achjimmy]

I used to get soot on the flap with the 2013 cruiser and I had twin exhausts that didn’t point down . But dry soot , glad to hear yours isn’t oily . I also had mine bent like crooks .

Tbh mate I’d loose the Donaldson. As others have said the air box won’t be improving the restriction that the Donaldson offering up .