DDK - Die Deutschen Klassiker

Ok....think i know whats comeing.....so be gentle..!!

My car puffs out blue smoke on a trailing throttle.... on start up...its fine...and under load....and hard acceleration.....no smoke.....well maybe a tiny bit....but its 29 years old...so i will forgive that bit...

its only when i lift off and have costed for about 1-2 mins at 50-60 mph (it dont do it thru town) that it puffs out a bit of smoke....if i put my foot down it goes...or drop a gear and get the rpm up...

it has a pretty bad oil leak....so my first thought it may have too much oil init....altought it went into the bottom mark and it still did it.......

im using 30w straight oil....is this right..??? milage is 176000...but must of had a rebuild along the way...

any help will me great...as im just starting to get into this....and am a real newbee

Sounds like wear in the valve guides ...

As for oil - do a search here on DDK as there have been a number of previous threads on the subject.

Personally I tend to use a good multigrade - usually Castrol GTX.

Yes, valve guides would be top suspect, followed by rings/bores. However straight 30 is very thin as the temperature comes up: I think you'll find that most of us are either running 15w/40s, or 20w/50 wieght oils.

Many (all?) straight oils also have no detergents: they are mainly marketed largely for the vintage car and bike folk, who run engines that have never had detergent oils through them. The problem is that if you suddenly introduce a detergent oil, it can loosen chunks of previously solid matter (carbon, metal particles etc).

If it was me, I think I would be tempted to buy two or three oil filters, and change to multigrade oil (buy a case from your local factor). If your oil pressure generally looks healthy 15w/40 would probably be fine. Run the car until the oil starts to take a fair bit of colour (perhaps 500/1000 miles or so) change it again, and repeat. Hopefully you will be able to gently clean up the engine, with no ill effects, and also having a slightly heavier oil could well reduce the smoking.

From my own experience, its well worth playing the 'conservation game' with a slightly leggy engine, as they always seem to be the ones that run best, and an engine rebuild is never going to be cheap!

NOTE: Now edited to reflect the fact I've just noticed we're talking 912, rather than 911, so I've cut the pressure figures out , sorry , however I think the other principles would still apply. Hopefully any engine work will be a bit more affordable though!

thanks....for the oil info...... its currently got a bad oil leak from the crankshaft oil seal...which im having done while im on honeymoon (about 3 weeks time)...so there is always new oil in it....lol....where can i get a oil filter from..? and is it a big/expensive job to do the valve guides...??? and should i do more while the engine is out...???

i dont have a pressure gauge...?? should i...??? and can i put one in...??

Justin

Its defo valve guides, just had my engine rebuilt (180k on the clock) and pretty much the only thing that showed heavy wear was the valve guides. It the exhaust valves, they're prone to it. The crank, pistons and barrels where all good and reusable, though I've had it bored to 2.1 now. The other thing that was well shot was the cam.

I wouldn't bet on your motor having a rebuild in its life time, they will cover that mileage easily.

Theres not much you can do to prevent it other than drop the engine, remove the heads and have the guides and new valves done. Do abit yourself, like dropping the egnine and removing the heads, then have the head reworked by a pro, might get it done for under £500 easy. Though like Pringles, 'Once you Pop You Can't stop'. Like me! and the full rebuild, carbs, exhaust, etc, etc, is approaching 2k+ I think, though I've stopped counting now.


As for oil and filter, use a good 10w or 20w/50 (I use Miller Oils), the oil filter is just a standard item that you'll be able to pick up from your local car shop. Mines a Fram item that's also fitted to Ford Seirra!!! cheap at least, same with the plugs just standard car shop stuff, might be an idea to remove one and take it along with you.

The temp gauge on you dash is also a pressure I think, it takes two readings one low down near the drain plug, the other topside near the dissy.

You might have a spare cylinder head temp sender that the EFI would've used, you could rig a spare gauge to if you like.

I found mine would run pretty hot when gunning it on motorways, though never going in red.

I'm with Nige.

If you have a 912E, this is the same engine (as near as damn it) as a 2.0l 914...

Bottom end (crank etc) is very strong.
Valve guides and piston rings wear with high mileages. The valve relies on seating in the head for cooling, so if your valve guides wear, less contact = they run hotter. Worst case is the valve breaks and dances on the piston! (very rare however)

Also the heads can crack round the cylinder heads.
Cams can go flat - not a show stopper , but reduced valve lift = less power.

But if your car is running strong - put heavier oil in and see how you get on. I know a few people who have rebuilt their engine to get rid of a minor irritation to open a whole can of worms... and introduce other probs!

Top end rebuild (valve guides and new piston rings probably about £800ish not including taking the engine out).

Best regards
Robster

Well. my 2.4E is smoking too. Pulls strong, and isn't drinking oil too fast, but sitting at the lights when the wind changes and engulfs the car in a blue cloud is something I could do without!
I'd guessed valve guides and piston rings, so have got quotes in for the top end rebuild...
The quotes are coming in at around £3K plus VAT. Am I asking the right people for quotes!?

Difference is your motor is a 911 6 cylinder, these prices are based on a 4 cylinder Type 4 motor. Totally different bad boy altogether.

£3k sounds on the ball to me for your motor, though I'm no 911 guru.

When my 911 was smoking badly, it was simply a leak from the cam covers. It appeared hideous both from the outside (lots of smoke) and dangerous inside (lots of smoke)!!

Replacement top cam covers (very badly warped) and new gaskets cured the problem.

Always look for the simple (and cheaper) cure first.

Ah Peter, I've done the cam covers. And the gaskets. Heart sinking.
One question, and you'll be good man to tell me, as your oil plumbing is the same as mine (external oil filler, you know what I mean!)...
There is (on mine at least) an uncapped pipe, about an inch long, just behind the oil filter in the engine bay, attached to the inner wing. Is it an oil reservoir breather?
What I do know is that once I'm getting plenty of blue from the exhaust, I open the engine lid and see that piping blue smoke out too. Any ideas? Have squinted at my Haynes, but can't work out what it is...!