What are the classic symptoms before a top end overhaul?

dmoolenaar

"The only time I see the smoke is in the morning on first startup. Sometimes very little other times one big cloud."

Mine varies a lot too depending on the weather.

Bo

"I sometimes can hear ticking from the engine, when I pass closely to something that reflects the sound of the car (a building, or something like that) at low speeds. Can't hear it from inside the car at all. "

That was how I first noticed mine ticking. (Open window waiting at redlight with a crash fence beside me). Otherwise I too can't hear it when inside the car.


Oil consumption: I'm not sure how much mine uses, but it's in the area of 0.2 liter or less every 1000 KM or so (figure not precise or long term "tested"). Anyway it's not much.

My exhaust pipe is more black than brown though

This thread is very good with many good posts - thanks guys. I'm getting more confident that what I need is to have the valves adjusted again, this time by someone who really knows what he's doing. In the meantime I guess I should avoid reving the engine past 6000 rpms?

[Wayne 962]

Excellent! I have a technical article on this very subject. It's an excerpt from my new book:

http://www.pelicanparts.com/techarticles/mult_Engine_Rebuild/mult_engine_rebuild-1.htm

-Wayne

[EdHut]

Hey Wayne,

I just read the article and you don't mention anything about the earliest engines, the 2.0 litre ones. Can I assume that the 65-68 engines are more durable than the 69-73 ones or at least similar to the 911T you mention?

My car is from '66 and the engine has run about 140K miles since a top end rebuild done at about 130K miles. Oil consumption is low IMO, just 1 litre in about 2000 miles.

Cheers,
Ed (who will of course buy the engine rebuild book 'just to be prepared')

[rstoll]

I am comfortable with the ticking. If their not ticking they're too tight, risking a burnt valve.

[cegerer]

Wayne - excellent article. Can't wait for the book! -- Curt

[hbrand]

What I do not get is why if the guides are worn but the oilseal usually not - should the oilconsumtion be up??

Just took my engine apart, the exhaust guides had 1/32inch play, the seals where intact, the pistons clean. !!!????

I think if the guides are bad you get bakfire at idle either in intake or exhaust.

Thanks, harold

[Sean Hamilton]

Originally posted by Wayne at Pelican Parts
Excellent! I have a technical article on this very subject. It's an excerpt from my new book:

http://www.pelicanparts.com/techarticles/mult_Engine_Rebuild/mult_engine_rebuild-1.htm

-Wayne

Plain laypersons English - even I can understand it.
After reading both that and the following article - "carbon deposits" I want get out there NOW and go for a "spirited" drive with the revs high.
That's at least something I can do - now knowing I'm actually doing my engine a treat.

Whilst I doubt I'll ever rebuild an engine this book will certainly de-mystify the mystery and give me confidence in what the process is.

Keep 'em coming Wayne, can't wait till "Next Month".

[Wayne 962]

Cool, glad to hear the reaction is good. That article is an excerpt from Chapter One of the new book...

The B&W version should be ready next week, or the week after...

-Wayne

[Glasgow 911SC]

Good article Wayne. Looking forward to the book. Just to clarify, 1qt is an American measurement, yes?! Whats that in metric for someone stupid like me?

I'm guessing an engine would be more inclined to burn / leak oil if a thin synthetic one is used. I for instance use 0-40 Mobil 1. Occasionally i get a large (scary) cloud at startup if my car has been sitting on a sideways slope.

[Rick Lee]

Yes, good article Wayne. So, before I run out and have a top end done, should I switch to a heavier weight oil? I'm using Castrol 20/50 now. What should I try next?

I'm running Mobil 1 0W-40. In spite of that I have no leaks and small oil consumption.

[Paul Franssen]

Glasgow-
1 US Quart = 0.9494 liter
1 Imperial (UK) Quart = 1.137 liter
1 UK Quart = 1.2014 US Quart.

Below (Russian) website is one of many "converters".
http://www.convert-me.com/en/convert/volume

This is a French one
http://convert.french-property.co.uk/cgi-bin/convert.pl

My Carrera has 195000 km (121200 miles) on the odometer (whatever that means, I have no way of checking whether this is the real mileage of my car, neither can I tell if the engine has ever been overhauled, but there are no leaks whatever). I have just run 2300 km (1430 miles) at 100 mph (speedometer, meaning abt. 145 kph real velocity) on "autoroutes" (dual carriageways...sounds quaint which it ain't), and multiple accellerations in 2+3+4 on Alpine "rallye-type roads (yellow and white on French Michelin maps). I consumed about one liter over that run, so we're talking a consumption of 1 U.S. quart per 1400 miles. Mind you, I switched from Castrol GTX semi-synthetic 10W-50 to full synthetic Shell Helix Ultra 5W-40, and effectively, she consumed rather more oil with the full-synthetic oil than before.
My car emits a white exhaust when starting the engine cold in the morning (air temp then abt 10-12 celcius, that's abt. 50-54 F), and -as far as I can see- no smoke when warm. Even though my mechanic said she needed her valves adjusted, which he subsequently did do, the valves tick quite a lot. The audio-volume of the ticking changes as the engine idles, and is drowned in the general din when revving her up/driving. My mechanic said "yeah, some of them tick, don't worry about it". Some of my friends 3.2 liters don't tick at all, purring-smooth idles! Accellerations are lively (an understatement), especially breathtaking over 4000 rpm in 2nd and 3rd gear (G50). During the above trip, my lady consumed an average of 11-11.5 litres of 98 Octane gasoline per 100 km, at speeds as indicated above. That's about 24.57 miles to the British gallon, or 20.46 miles to the U.S. gallon.
Why doesn't everyone go metric???? (after the next war looks quite improbable )

[Glasgow 911SC]

Thanks Paul.
I'm going to keep an eye on my oil consumption to see how I'm doing.

[Roland Kunz]

Hello

Best is not waiting to long as worn out valveguides also waers the steam on the valves and usually forces to renew the valves as well.

Renewing the guide seal on a worn guide will only work for a short time.

Normaly the valve guides wouldn´t need a seal but with modern oils ......

Grüsse

[schulr]

With all this collective knowledge on valve guide wear and oil consumption, perhaps we should develop a pm plan to forestall a top end? Anyone have any success using additives? I smoke at start up but it seems to go away after warming up, have not noticed any smoking while driving but need to check this further. I am sure there is something as the consumption is around 500/qt but is also sometimes less, depending on driving.

Bob