highsociety88

Hi guys im new to the forum and to Porsche ownership.

I recently bought an 88 Carrera targa with 140000 miles on the clock, the car has a full service history with Porsche agents and drives like a dream. However there is one issue with the car;

I recently took it for an annual service to a very reputable Porsche dealer here in Johannesburg and i asked him to do a valve adjustment as it had started to get very tappety. While we were chatting with the car idling next to us he noticed a little smoke coming out of the exhaust which i had never noticed before and told me it had worn guides and would need a top end rebuild.

He went on to say that he wouldn’t do a top end without replacing rings and big end bearings (what do u guys think of that?).

I told him to do the oil and filter change and I’d think about doing it all in the near future. Since getting it back from the service, I’ve only noticed it smoking randomly and usually when its hot. The valve noise is clearly coming from the left bank and appers to worsen as it get warm. Oil consumption isn’t bad at all and is well within the manufacturers specs.

I'm sure it is due for a top end but how serious is the problem if not attended to immediately and what other damage can be done? Can it break a valve as a result of this problem?

jakeflyer

A little smoke every now and then does not seem to be a big worry; do you have the oil level correct when it is fully warm, and did you change the type of oil? Did the valve adjustment make any change at all? Are you sure he said big end bearings?? that does not make any sense. Did you do compression to see if there is a weak cyl on the loud side? Does the noise get louder as the rpm goes up?

ricster

If it were me..I would sell the car and move on. If you like that year/vintage then I would pursue a lower mileage unit. You can still get top dollar for your car without investing money and then buy another low mileage unit...then you will be ahead of the game

jakeflyer

Funny you should say that, it was my first reaction. Same situation with a '76, sold it and moved on.

Auto_Werks 3.6

Hope you two sold with full disclosure!^^

High society, at 140k you are in a mileage territory where it might be false economy to top the engine without going all the way. If you were anywhere up to 100k I would argue for a top end only service. Not that the service can't be done, but the mechanic has to sign his name to it. If he charges you $5k for a top end, and you spin a rod bearing in the next 40k miles, no one will be happy with the overall outcome.

I doubt that you're valve guides are in dire condition if the oil consumption is less than a quart every 800 miles or so. You didn't mention if the mechanic followed through with the valve adjust, or just threw his hands up and decided that it needed rebuilt. If it's the latter, you need to find someone who knows 911's to do the valve adjustment and precede from there.

As far as the oil smoke goes, Jake is right on; new 911 owners tend to miss the oil checking procedure. The engine must be up to full operating temperature, and running to check properly. If you miss a step here, you will most likely overfill and cause a lot of smoke.

If you do not have excessive oil consumption, and the valves were adjusted properly yet the loud tappet noise persists, you could possibly have a worn rocker shaft / rocker combination. It could still be an isolated valve guide issue. A good look at the spark plugs might help guide you here. I'm not 100% positive, but I believe you could replace a rocker & shaft or two without taking the engine apart. Someone please correct me if I'm wrong on that.

theiceman

Get a leak down test . This will give you a really good idea of the health of the engine .. Being a carrera I would not be surprised if the valve guides are worn but it is not the end of the world. If the leakdown fails the shop should be able to tell you if it is from the guides or rings.
If your oil usage is good i would not sweat it to much. I would also redo your valve valve adtment. Any 'reputable" mechanic should be able to take those valse covers off and diagnose a noisy tappet i the issue is not straight gap .. I am betting it is.

Many htings in life depend on your mechanical know how combined with your budget.. it is easy for us to say strip it doen and rebuild it ... try to take a bit of a methodical aproach.

highsociety88

Thanks for all the advice guys!

To answer some of your questions and make things a little clearer;

Valve adjustment wasn’t done as he said there’s no point replacing the gaskets and paying for the labour twice as he was adamant it needed a top end rebuild.

His reasoning for doing big end bearings is that gain in compression after guide fix might cause bearing problems later on.

As for the oil level; When i received it back from the service it was and still is at the top of the gauge and dip stick at idle while at operating temp. It does however drain the tank under acceleration causing the needle to drop to the bottom, which i assume is correct. But like i said oil consumption is all good as I’ve probably done 600 odd miles since service and it hasn’t dropped.

I think a leak down test is next on my list.

As far as selling and moving on, well the thought has crossed my mind as i would prefer a coupe. Problem is good clean Carreras are hard to come by here in South Africa and i believe mine to be one of the good ones, rust free and completely original. If its a cheap easy fix I’ll do it and keep the car. If it’s a pricey big job I’ll try get my money back with a full disclosure.

Best thing to do for now is get a proper diagnosis.

Thanks again for the advice!

Daniel Dudley

I am just an average Joe, but I check the oil with the dipstick, at idle, after driving until hot and letting it idle for one minute. Filled to the top line is too much, in the middle is a couple of quarts less, and plenty of oil for a happy engine. There is no way that you can tell what is up with the valves if they haven't been adjusted. They need to be adjusted before you can tell what is up with the engine.

If it is a hot day, and the engine is hot, with hot oil, that would be the time to look at the oil pressure. You should have 1 bar per 1000 RPM, should be at least three bar at 3000, and more at higher RPMs. If you have good oil pressure, and the engine is hot, you have good bearings. These engines have been known to go 200,000 miles and MORE without needing a bottom end rebuild. However, you do want to use the right oil.

I would get a second opinion. I would get the oil in the center of the stick, I would get the valves adjusted, and I would monitor the oil pressure. A leakdown or compression test would also be a good move. You don't get a new foundation because your roof leaks. You don't get heart surgery without a second opinion, and at least a few tests.

BTW, do a search on oil. My SC has a high output engine, and 222,000 miles on that engine. It wants the proper oil, but it runs like a champ. It doesn't like to be overfilled, and I did get a second opinion when I was told I needed new camshafts. Maybe you do need work done on your engine. Check it out.

highsociety88

Points taken Daniel, all sound advice.

I think the very reason im questioning this all so much besides the fact that it aint cheap is that the car runs so incredibly well!

Will definitely get a second opinion which will hopefully be based on facts after a valve adjustment and leak down test.

highsociety88

Oh and i forgot to mention, oil pressure has always been very good according to the gauge. Compared it to some SC's I’ve driven and mine picks up pressure from quite low down in the rev range. Oil pressure sensor was replaced recently due to a crappy connection so all is good in that department. I'm very weary of oil pressure loss as i recently ran a bearing in my Ducati's motor due to a faulty pump and that definitely wasn't cheap.

Norske

Sounds to me like a valve adjustment is in order & I do not believe you need top end yet. When you have smoke under deceleration is a sure sign of valve guide wear. If your oil level on the dip stick is at the top when warm, you have too much oil in the tank and could be the cause of your smoke. The level should be in the middle, not the top. When you accelerate, the gauge will go to the bottom, not to worry about that.

However, when you do a top end, checking rod bearings & rings is a very good idea.

TT Oversteer

Does this mechanic have any Porsche experience? The tapping noise is probably just a slightly loose valve clearance.

Replacing valve guides will not give you higher compression.

Recommending a top end rebuild without doing a leak down test is irresponsible on the mechanic's part.

Your oil level is too high and could cause occasional smoke. Take out one quart so the level is in the middle between the two marks on the dipstick.

jakeflyer

----Auto_Werkw 3.6-----------------------------
Yes indeed he got all the facts. It went to a German rebuilder/dealer who did very well with it and I got my money out. He called me a few months ago when he was back here and asked if I had another car to sell. I have been in the same house with the same tele # for 40 years, 100% on Ebay and many friends (and no one mad) from airplane, bike, and car deals.

I do understand your statement, having made a buy, more than once, that was not as presented. Two were very close calls (death) involving antique airplanes. Three times I paid and went back and the item was gone or parts taken. Sometimes people really do not know, sometimes they lie.

ked

high, congrats on the '88, & some good advice here. you need an expert 2nd opinion, someone who has yrs of experience on 3.2 engines. if still not comfortable with what you are hearing, get a 3rd. among the Porsche community in SA, there is bound to be a few "go-to" shops - talk w/ longtime owners to find out who they are. the payoff will not just be clarity on your current concerns, but insight on other issues they might find or will arise. cheers!

highsociety88

The mechanic is supposedly the best we have here but i reckon even the most trust worthy mechanics like to create work for themselves from time to time.

If the valve guide is worn to a point that the valve isn’t seating properly surely it will cause leaking through the valve and so lowering compression on that cylinder....or am i way off?

Agree with all on the leak down test so definitely gonna get that done along with valve adjustment before anything else.

Drove the car last night so i could get it up to temp and check oil level properly Here is a pic of my gauges at idle and up to temp.

Also checked the dip stick and its about half a centimetre below full.

Next question is what’s the best way to drain some of the oil out?