Track day Chicane, white smoke, red flag, help

[wrightp]

Hi folks

I attended a Novice TVR track day at Blyton Park on Friday afternoon which was organised by the RO for South Yorkshire TVR club. Nice event with plenty of time on track and thanks to Anthony (QBee) for help advice and passenger ride.

BUT:
My car didn't do so well!
Chimaera 500 - V8D upgrade with all the usual bits but standard tyres, and overall looks. Valvoline Racing 20/50 as recommended by Rob (Engine builder).

The car was great on the straights and most corners but in two specific areas clouds of white smoke were coming out of the exhaust.

The specific circumstances were straight then brake, followed by fast left and immediate hard right (Chicane) and smoke could be seen in clouds out the back. QBee followed me after we took some oil out (Slightly overfilled) and at steady pace all ok but as soon as I cornered hard again the smoke came back. This was at a good pace on standard/ road Toyo T1R tyres. Rest of Track Day used car as point and squirt fun and Miss Daisy around corners.

My initial thinking was that the oil was surging as there is no baffled sump but other chimaeras without baffled sumps were there and they didn't have an issue. My thinking now is relating to crank case breather from flame trap to plenum. Could I have been filling the right hand (Drivers side) rocker cover with oil on left handers from surge then on immediate right turn oil entering plenum via breather pipe?

As soon as the car was back on the straight no oil smoke and no oil under the bonnet, or on the ground.

Strangely I did notice occasionally when the smoke was coming out of the exhaust in the chicanes that there was some coming out of the enlarged bonnet vents (As on Chimaera 500) mainly on drivers side??

Could anyone help me understand what has been happening and how to address the issue?
Oil catch can perhaps??

Cheers
Phil.

[AV8]

wrightp said:

Strangely I did notice occasionally when the smoke was coming out of the exhaust in the chicanes that there was some coming out of the enlarged bonnet vents (As on Chimaera 500) mainly on drivers side??

I had a similar problem yesterday on a track day. When exiting a chicane I was getting something coming out of the right hand bonnet vent.

It turned out to be power steering fluid as I had over filled the reservoir. I mopped some out with a cloth and all was fine for the rest of the day.
There was fluid all over the rocker cover and while I could smell burning I don't think there was much smoke.

Are you sure the smoke was coming out of the exhaust, as sometimes something like leaking gearbox oil can burn on the exhaust and look like exhaust smoke from behind.

Also, did you check for coolant loss?

A

[griffdude]

Hi Phil, oil surging is a right pain as you've found out. Unusual with the type of tyres you were on though.
The best fix is to fit a baffled/gated sump: Mulfabs make them. I use the same oil as you with one of their sumps & no more surging.

[p5000ko]

Long Shot, have you been topping up brake fluid lately? had similar with brake fluid running into Servo and leaking out at corners heavy braking into inlet causing white smoke .

[griffdude]

p5000ko said:

Long Shot, have you been topping up brake fluid lately? had similar with brake fluid running into Servo and leaking out at corners heavy braking into inlet causing white smoke .

Good call. Leaky reservoir cap? Look for streaks on the paint.

[wrightp]

AV8 said:

I had a similar problem yesterday on a track day. When exiting a chicane I was getting something coming out of the right hand bonnet vent.

It turned out to be power steering fluid as I had over filled the reservoir. I mopped some out with a cloth and all was fine for the rest of the day.
There was fluid all over the rocker cover and while I could smell burning I don't think there was much smoke.

Are you sure the smoke was coming out of the exhaust, as sometimes something like leaking gearbox oil can burn on the exhaust and look like exhaust smoke from behind.

Also, did you check for coolant loss?

A

Hi - thanks for idea.
We are certain that the smoke was coming out of the exhaust as two other chaps deliberately followed me around to see what they could see and the smoke was coming out of the exhaust. Must admit though that cannot think how a little would be coming through vent at same time. No oil or fluids visible under bonnet when in the pits.

I did check the coolant just now and it was near the bottom of the filler but I didn't check it before the track day so unsure if it used any on track. Found a little pipe or overflow near filler though see below:

[wrightp]

griffdude said:

Hi Phil, oil surging is a right pain as you've found out. Unusual with the type of tyres you were on though.
The best fix is to fit a baffled/gated sump: Mulfabs make them. I use the same oil as you with one of their sumps & no more surging.

Thanks for that.

Can you describe the surging you experienced in the past - does it sound similar to my issue given the tyres in question and others running fine on the day?

[wrightp]

p5000ko said:

Long Shot, have you been topping up brake fluid lately? had similar with brake fluid running into Servo and leaking out at corners heavy braking into inlet causing white smoke .

Interesting call that!

Checked brake fluid reservoir on the day after the smoke but no apparent drop from full and no streaking on inner wing.

[Pupp]

Not unusual for oil to accumulate and pond in the rocker chests, especially at high rpm, which can be drawn down the guides on over-run - restrictors are sometime fitted on the oil feed drilling to limit flow to what is needed for the rocker gear

[wrightp]

AV8 said:

I had a similar problem yesterday on a track day. When exiting a chicane I was getting something coming out of the right hand bonnet vent.

It turned out to be power steering fluid as I had over filled the reservoir. I mopped some out with a cloth and all was fine for the rest of the day.
There was fluid all over the rocker cover and while I could smell burning I don't think there was much smoke.

Are you sure the smoke was coming out of the exhaust, as sometimes something like leaking gearbox oil can burn on the exhaust and look like exhaust smoke from behind.

Also, did you check for coolant loss?


Checked PAS fluid which was just below normal level between top and bottom mark. Interestingly I just had this replaced (The hoses and fluid) for a replacement set through Mr Zubak and I would have thought the reservoir would be still full.

Is this a little air entry hole in the picture on the filler cap?



A

[wrightp]

Pupp said:

Not unusual for oil to accumulate and pond in the rocker chests, especially at high rpm, which can be drawn down the guides on over-run - restrictors are sometime fitted on the oil feed drilling to limit flow to what is needed for the rocker gear

Thanks for thought.

Only every happened in left right chicane rather than all braking and turns.

[phazed]

Years ago I had a very similar problem on a TD.

People who were following me assured me that it was coming from the exhausts.
It turned out it wasn't from the exhausts.

The dipstick tube had raised itself by about 5 mm and oil was forced out the block to drop on to the red hot exhaust resulting in white smoke pouring out the back.

Of course, soon as I backed off, it stopped.

The simple cure was to fit a spring that I hook over the dipstick handle to pull the dipstick down.

Since then, never a problem.

[QBee]

From 20 yards behind the car, it was just after he had straightened up after final (third) element of the complex, and it looked like Phil had either blown the turbo he doesn't have, or elected a new Pope.

Big cloud of white smoke out of both pipes, Phil's car no longer visible. Cleared in a couple of seconds, as if a leprechaun had squirted one shot of a few mls of neat oil into one cylinder

The corner was a longish left hander, off camber, so there was a fair degree of lateral G force to the right, and the left hander ended up in a right left chicane, which also involved braking from 85 down to 50 mph.

I have driven corners like this before, on track tyres and faster than Phil, and both with and without a baffled sump, and never had the issue. So it's something the car is doing that it shouldn't be doing.

[Bluebottle]

Sound more like oil on manifold to me, have you checked the rocker cover seal? and also check top back of engine for valley gasket leak.
I had this once just after an engine rebuild which turned out to be oil coming out of the rocker cover...I had removed the HT lead clip but hadn't put a screw back in the hole not realising they are drilled through.

[phazed]

Bluebottle said:

Sound more like oil on manifold to me, have you checked the rocker cover seal? and also check top back of engine for valley gasket leak.
I had this once just after an engine rebuild which turned out to be oil coming out of the rocker cover...I had removed the HT lead clip but hadn't put a screw back in the hole not realising they are drilled through.

Exactly my thinking.

Valley, rocker boxes or, the rarer dipstick tube!

[sapper]

It was definitely coming out of the exhaust pipes in great volumes, I was right behind him at one point and lost him in a cloud of smoke. Far too much to be coming out of the rockers or dip stick, it was coming out under pressure

[wrightp]

Bluebottle said:

Sound more like oil on manifold to me, have you checked the rocker cover seal? and also check top back of engine for valley gasket leak.
I had this once just after an engine rebuild which turned out to be oil coming out of the rocker cover...I had removed the HT lead clip but hadn't put a screw back in the hole not realising they are drilled through.

Hi
Thanks for thoughts.

The engine has been built now for 2 years and runs well, and as far as we could see there was no oil under the bonnet in the pits after we looked very closely. The view I am getting from thoughts and people on the day is that the smoke was coming out of exhaust so that is tending to lead me to the oil via intake/ plenum theory at present.
Any further thoughts very much appreciated.

[phazed]

Simple job, remove the plenum.

Good chance that there is oil in there that has been sucked in through the breather from the rocker box.

[wrightp]

Well I have been driving the car over the summer OFF TRACK without any issues but would like to have another go at a trackday, so I have bought an oil catch can and will buy a new Flame trap and o ring seal. Are there any tips to fitting an oil catch can into a positive crankcase ventilation system. The one I have bought has an inlet and then outlet with a visible oil level tube.

I was thinking of mounting it to the alternator bracket where the air con system would go if the car had A/C.

I also think the tubing needs to be oil and heat resistant.

Any thoughts or help chaps?

[QBee]

Where are you planning on doing your track day, Phil?