Hi to all,

Recently i read in one of the threads to bring engine to operatoring temp , leave idling for 10 minutes and the give a good rev and see if smoke blows from exhaust. Well this does happen for my TF.

I am assuming that this means the valves are worn and need replacing.

Also i am smellng oil burning very strong and there is signifcant smoke coming from engine at times. But not duting every trip. Any thoughts?

Are replacing valves simple.

I would have thought that depending on the colour of the smoke it could also be worn piston rings (blue smoke).

But to answer your question, replacing valves isn't simple and either is piston rings. Both require significant dismantling of the engine.

Smoke in the engine compartment may be leaking rocket cover seals. Easy to fix.

Smoke from exhaust may be valve stem oil seals, or worn rings. Not so easy to fix.

If your car has high km. a thicker oil may help the exhaust smoke. How many km on the engine, and what oil do you use?

6g75 time!

edit: A trick i've used on bikes (and I imagine it would also work on cars) to see if its valve stem seals is to find a downhill slope and roll down it using as much engine braking as possible (lock it into 1st/2nd) coast as long as you can then hit the throttle hard. If heaps of smoke pours out then yep its the valve stem seals. Engine braking creates a vacuum in the cylinders, so they'll draw oil into the cylinders. Then when you hit the throttle it'll burn it off as quickly as possible and throw smoke out. If its just rings, this won't occur at least not to a significant degree

[QUOTE=MadMax;1622597]Smoke in the engine compartment may be leaking rocket cover seals. Easy to fix.

Smoke from exhaust may be valve stem oil seals, or worn rings. Not so easy to fix.

If your car has high km. a thicker oil may help the exhaust smoke. How many km on the engine, and what oil do you use?

Using 20/50 oil and engine has 255,000km

Considering new motor like millenium has suggested.

The amount of oil on the underneath the engine is incredile, have never seen so much oil.

Rego due next month
6g75 that is the 3.5lt version isnt

6g75 time!

edit: A trick i've used on bikes (and I imagine it would also work on cars) to see if its valve stem seals is to find a downhill slope and roll down it using as much engine braking as possible (lock it into 1st/2nd) coast as long as you can then hit the throttle hard. If heaps of smoke pours out then yep its the valve stem seals. Engine braking creates a vacuum in the cylinders, so they'll draw oil into the cylinders. Then when you hit the throttle it'll burn it off as quickly as possible and throw smoke out. If its just rings, this won't occur at least not to a significant degree

Will give it a go, i think the same re new engine...

Oil on the underside of the motor did not get there by burning, clearly you have an external leak as well as an oil burning issue. External leaks are usually considerably easier and WAY cheaper to fix than a new engine, it's just a case of cleaning everything down and having a good look and fixing what's cactus. Also, a blocked PCV system (any one of the three hoses, two valve cover baffles and the PCV valve) can cause oil burning issues that show up much like leaky valve stem seals (ie. big puff of smoke after idling) and are solvable by replacing or cleaning a few basic and relatively cheap bits and pieces. My 'blown' engine used to smoke out half a suburb on leaving a car wash, less than $100 later with a new set of PCV hoses, valve and clean rocker baffles and there's barely a haze from the pipe. Still burns a bit, but hey, it's done nearly 300,000.

I dunno, to me replacing an engine because it's a bit leaky is kinda rash, but to each their own I guess. In your position, first thing I'd do is make sure the engine is being properly ventilated internally.

I dunno, to me replacing an engine because it's a bit leaky is kinda rash, but to each their own I guess. In your position, first thing I'd do is make sure the engine is being properly ventilated internally.

I agree. Find the cause of the problem first, investigate repair options. If the economics of repairing the problem outweigh the benefits, then consider the larger outlay of a replacement engine.

A few of the first things I bought and fitted when I got the wagon was new PCV/Blow-by hoses and a new PCV valve; for preventative maintenance more than anything else.

I dunno, to me replacing an engine because it's a bit leaky is kinda rash, but to each their own I guess.

Easier though. Just drive over to Mal, tell him what you want, hand over the cash.

edit: A trick i've used on bikes (and I imagine it would also work on cars) to see if its valve stem seals is to find a downhill slope and roll down it using as much engine braking as possible (lock it into 1st/2nd) coast as long as you can then hit the throttle hard. If heaps of smoke pours out then yep its the valve stem seals. Engine braking creates a vacuum in the cylinders, so they'll draw oil into the cylinders. Then when you hit the throttle it'll burn it off as quickly as possible and throw smoke out. If its just rings, this won't occur at least not to a significant degree
Will give it a go, i think the same re new engine...

This is really no different to leaving it idling. Very strong vacuum is created by an idling engine.

I understand the valve stem seals can be changed without removing the heads. If the rocker covers are leaking too, perhaps get a price for someone to replace the valve stem seals and rocker cover gaskets at the same time.

Mal had said time and time again by far the most common oil leak on these cars is the rocker gaskets. Replace them and your valve stem seals and you should be back in business.

?????????????
It is vastly different from idling. The vacuum under heavy engine braking is far more than idling. For one the revs are much higher. The vehicle is only being slowed down by the engine, when its idling, combustion is making the engine turn. And finally, there is no combustion when coasting as no fuel is being added, giving the oil a chance to pool up so when you do hit the throttle it'll all burn off suddenly and be extremely obvious. Rather than slow and continually burnt off every cycle and you may not even notice

Coasting downhill - will suck up oil past the rings as well as past the valve stem seals.
Idle - less likely to get leakage of oil past the rings due to combustion pressure.

You could just keep an eye on the oil level in the engine to get an idea of how much escapes through leaks both outside the engine and inside?

Fix the external leaks and drive the car gently, in the bottom half of the rev range, and check oil level often.

When a police man gives you a defect notice because your car is doing an impersonation of a low flying crop duster it's a hint to fix the engine. lol

Connect a vacuum gauge to the manifold at idle, and then under heavy engine braking. You will see very little, if any difference.

I used to have an in-dash mani-vac meter in my Hillman 1000 years ago, and pressure does drop (or depression increase) on zero-throttle deceleration in manual cars (MUCH fun to be had dropping from 4th to 2nd and popping the clutch for hoonish compression lockups... and clutch rebuilds... but I digress), presumably much less so in an auto. Regardless, a depression in the cylinders will draw in oil wherever it's leaking from, shot rings will give the same puff of smoke when planting the pedal at the bottom of the hill as leaky stem seals. Letting the engine idle for a while, as said previously, lets the oil pool around the valve stems where it can flow through leaky seals under its own weight, gravity tends to work against oil being drawn up through dodgy rings.

Well my experience has been that a long coasting run will show A LOT of smoke if the valve stem seals are bad (not car engines so may be different) whereas if the rings are worn it will show a little more smoke but not drastically so. Bad rings will be more willing to show up under hard acceleration, and also smokes more if the engine is cold since the rings don't seal as well until they warm up

Can't distinguish between oil getting past rings and leaky valve stem seals?

Solution: Strip the engine and replace both rings and valve stem seals.
Or see Mal for something fresher, not necessarily a 3.8L engine.

I can't imagine how incredibly shit of a job changing 6 sets of rings with multiple pistons on a single crankshaft would be. It's annoying enough sliding a single cylinder over a piston while compressing rings, let alone multiple

I can't imagine how incredibly shit of a job changing 6 sets of rings with multiple pistons on a single crankshaft would be. It's annoying enough sliding a single cylinder over a piston while compressing rings, let alone multiple

Hey, it is NOT a motor cycle engine! The pistons drop down into the block, actually. Need to be unbolted from the crank to come out so you can change the rings. A ring compressor makes an easy job of it. A few tricks to it, but no biggy.

Hi all,
Thank you for your feedback on my problem. I have decided to change the rocket cover (rear). The PVC Value seems to be working. I plan to go orginal in parts, previous price for rear rocket cover was $95 they have been redesigned (hopefully to correct the persistance oil leak this forum hears about) the rocket cover and it now cost $270. I dont mind spending that amount it it work and stops the leaks.
Still thinking of have an spare engine in the garage can get one in the illawarra $350 eith warrenty.

Thanks everyone