996 Valve Job

bosalls5 · 06-19-2008, 03:58 PM

I'm obsessed with this car (see..fuel injectors). I finally found a local shop that gave me a good base line for fixing my burnt valve. Question..... is the 3.4 / 996 engine worth a valve job / both sides for ($6g's) vs a factory re-built engine for $13g's with warranty. Keep in mind that this is engine # 2 (#1 failed early) with all of the bugs out. Is the 3.4 still a throw away engine or worth the work??? Thanks for listening, Bob ('99 996 Cabrio)

glenndeweirdt · glenndeweirdt's Garage

How much to just replace the valve?

ferdsgt3rs · 06-21-2008, 06:42 PM

Did you have a warrenty on the #2 Motor ? I would go for the new motor. wow you sure are having crap for luck

Ferd

bosalls5 · 06-23-2008, 02:24 AM

Everyone including dealer and independents wouldn't entertain the idea of just fixing the the 1 valve or making the down cylinder good. Since all of the other cylinders were testing out ok I thought that was a reasonable request but like I said none of mechanics like that idea at all. I was hoping to here from someone with an extensive background with the 996 motor / valve job before I went with the idea. Now it looks like I'm going with the factory re-built again. Thanks again, Bob A

ferdsgt3rs · 06-23-2008, 03:48 PM

There aren't really any Shops that have REAL experience, like the air cooled version, Keep up the warranty and good luck.

911quest · 06-24-2008, 10:30 AM

My question is did the shop figure the reason for the burnt valve. I would make sure of this before I spent 13k on another motor.

bosalls5 · 06-24-2008, 03:41 PM

The dealer through bore scope examination found that a pizza...wedge shaped piece broke off the intake valve. Then they followed with...........that is very rare for this to happen. "WE DON'T SEE THIS VERY OFTEN". Previous hints were just a "check engine light" followed later by a rough idle and slow start sequence (extra revolutions to start).... then to the dealer. I was hoping through this tech forum to determine the value of a valve job vs an engine replacement. I bought this car in October... 1 owner and the engine replace under warranty @ 16,000 miles. Knowing about the early engine troubles and this car already on #2....I thought I was over the hump with engine issues...... so I bought the car. It now appears that any major engine work results in skyrocketing costs to the point that an engine replacement is a smarter move. The dealer was going to work the head plus parts for 10g's but if the head were bad and needed replacement add another 2g's. I found a local shop to do both heads for 6'gs but again if a needed a new head... I was back up around 8g's. So I decided to go with the factory re-built (with 24 month warranty). Just for argument pulling the heads off a small block chevy is no big deal ..... an option to consider, much like the air cool Porsche engines. Sorry... way to long, just venting!

bosalls5 · 07-14-2008, 07:27 AM

New engine is in and running like a top! Hope this is the last of my issues. Thanks again for all your help, Bob A

Porsche1036 · 07-18-2008, 10:59 AM

Bob, just to ease your mind a little, a lot has change since '99-your new factory reman engine will have all the updated and/or upgraded parts of the current engine( i.e, rear main
seal improvements and intermiediate shaft redesign just to name two). Mike

herman maire · 07-21-2008, 03:58 PM

I dont know man.... this is pretty insane.... replace a motor because of a burnt valve. I know everybody says the 996 motor is disposable but isn't this a bit much.

A quick story.
A few years back I bought a used bmw 3 series, it was then, a 4 year old car, pretty new for me. Had the car inspected before I bought it and everything checked out. Long story short, 50 miles from home there was this long up hill, I couldn't help myself so blasting through 2nd and 3rd the car was humming ..... I felt a little stumble, didn't think anything of it until I got home and felt a stumble at idle.

Fast forward, I ended up with a burnt valve and I got the same "I have never seen that happen before" from the mechanic. They wanted $2500 to pull the head and change 1 valve valve.

I ended up pulling the head my self out doors and brought it to a local cylinder head guy who changed the valve and went through the complete head for $390.

I know its not a 996 but a cylinder head is a cylinder head. Just wondering, did you ever have the chance to speak to a cylinder head repair shop to get some feed back on the chance of them fixing it? I wonder what there reply would be. Race Shops do change the cams in these motors dont they?

12k motor because of a burnt valve..... I am REALLY blown away and am sorry you got stuck with the bill. I would be soooo furious.

Britwrench · 07-21-2008, 04:24 PM

Cars and times change, comparing an old design BMW 3 series ( I take not with the VANOS as special tools are needed to set that up) and the current M96 engine is not relevant.

The M96 engine has gone through several updates and repairing an engine with known potential problems presents the repair shop with a liability and warranty issue.

Installing a Porsche remanufactured engine may not be the cheapest way out, but for shops and the vehicle owner, it is a known end product.