Survey. Engine rebuild and mileage.

[sugarwood]

Some people insist that a 911 with 100k miles needs an engine rebuild.
Let's collect some data.

Has you car ever had an engine rebuild? or a top end?
If not, what are your current total miles with no rebuild ?

[SiberianDVM]

AFAIK: no,no, and 240,000 miles

[steven12xu]

‘86 Carrera at 135,000 miles. Fried a crank bearing due to blocked oil feeder. Total rebuild to 3.4L. Much improved performance.

[Marko888]

87 3.2. 185k miles. Front main seal leak meant it had to come apart to fix.

[chrisbruck]

'87 3.2, 147k, top end only, lots of oil past the valve guides

[dyerkes]

‘87 with 104k had top end with previous owner at 94k; currently undergoing a full year down at 104k prompted by broken head stud but decided to fully disassemble just to inspect to make sure bottom end was in good shape. Found that a couple other headstuds had already been replaced; intermediate shaft bearings pretty worn; rod and crank bearings were good but I will go ahead and replace since I am in this far. Also doing a few upgrades while I have it apart.

I don’t think there is any magic potion. If you know the complete history and feel fully comfortable that it has received regular oil changes from the get go than you should go well in to the mid 100k, but you will likely have had a valve job prior to then.

[darrin]

Originally Posted by sugarwood

Some people insist that a 911 with 100k miles needs an engine rebuild.
Let's collect some data.

Has you car ever had an engine rebuild? or a top end?
If not, what are your current total miles with no rebuild ?

If your 911 with 100k miles is consuming a quart of oil every 600 (or less) miles, I'd "insist" that it needs a top end rebuild to address/resolve the underlying oil consumption issue.

My 86 Carrera was doing this at 75k miles and a top-end teardown disclosed severely worn valve guides and cam lobes -- a top end rebuild completely resolved these issues and 100k miles post rebuild, I was still getting well over 2k miles per quart of oil. Understand this premature valve guide issue affects a disproportion share of '86 (and '85, or was it '87?) 3.2 engines, but that most are not affected. My situation could also have been accelerated/caused by its use as a daily driver in DC with hot weather/ac use/stop and go traffic.

[dkirk]

Performed a top-end overhaul at 113,000 miles on my '88 coupe in 2011. Heads sent out to Anchor Atlantic for new guides, valves, seals, etc. They did a beautiful job at a reasonable price. Installed 964 cams and new head studs while apart. Did a careful assembly and engine has not leaked a drop of oil since.

I was going through 1 quart of oil every 600 miles before the overhaul with some blue smoke in the exhaust after extended idling. Now engine consumes 1 quart every 2500 miles and exhaust is clear. I did not split the case as oil pressure was excellent, and no trace of filings on the mag plugs or in the oil filter. Closing in on 150,000 miles and engine continues to run perfectly. The experience in working on this beautiful engine was well worth the effort.

[Dan J]

The experience in working on this beautiful engine was well worth the effort.

+911 They are special!

[proporsche]

resealed back in 2009 ,still original piston and cylinders...today mileage is in my signature

[petr916]

'80 Targa SC, complete overhaul at 136k miles. During 2019. Top-end was necessary - broken Dilavar head studs. Bottom end - for safety.

[Aurel]

The problem is that head-studs are usually broken at 100k miles if they haven’t been done before, and then since the engine is out it is a good time the refresh the top end. And sometimes the bottom end too (slippery slope).

[DWeg1998]

173,000 never been opened up, crossing fingers

[Fairview]

My 84 had a broken cylinder head stud, so we pulled engine, freshened up heads, all new seals, and any kind of service item such as fuel injector rebuild.

At 67,000 miles, the wear on the cylinders and internals was imperceptible. Everything looked perfect inside. It was a lovely thing to see and it made a believer out of me that these engines can go a quarter million miles and still be doing fine. On the other hand the broken stud was a bit horrifying.

[MBAtarga]

'83, 119k never opened.

[Rodek]

My '78 is currently getting a top end rebuild. 151,000 miles.

[bobb169]

At 85,000 top end. 140,000 complete 1970 T

[capt911]

1983 SC 158,000 miles. Broken head studs no real oil consumption. As long as we had it apart did the top end. Ended up getting an unexpected income tax return said what the heck spit the cases and do the bottom end. Have had the car 25 years will out last me now.

[shadowjack1]

My 88' was burning oil, due to valve guides . Puller the engine for a top end job. New guides, all valves, rings,studs and chains with sprockets at 120,000 miles.

[carreradpt]

Did a top end on my 85 at 162K miles in Oct 2012. Had messed up the threads on my #6 by not tightening the sparkplug and then missing the torque. Damn! I was burning less than a qt of oil every 2K miles. Not a leak yet and I have put over 40K since.