Thinking of buying a 85 911
glenncof
01-24-2007, 10:59 AM
THIS WAS IN REPLY TO A PRIVATE MESSAGE:
After personally putting on almost 160K miles on my 1985 (now at 175k) I think I'm qualified to answer this question.
Overall this car is probably the most reliable vehicle I've owned, it has NEVER left me stranded. Early on I left maintenance to a local shop but in the last six years I have done all of it.
Here are my specific comments in no priority.
1) Oil changes. I would look for records and do 3000 miles with 20W50 (unless cold climate) using Mahle OC-54 filter. This engine has brass valve guides that wear and oil consumption is high (600-1000 miles/qt is typical even in 90's models) Takes 12 quarts, has two drain plugs. Try to determine oil consumption. You could also check valve guide wear by having owner drive on highway/accelerate and then back off, look for smoke. I have not had my valve guides replaced even my mileage and get ~1000 miles/ qt. and I did 7500 mile changes until about 110K.
2) It has a porsche design 915 transmission used in '74-86. It's the weak spot, I believe, on the car. The G50 tranny (Brog Warner?) was in 1987. The 915 has brass syncro's that don't like synthetic fluid. Check service records but probably just change tanny fluid to Swepco 901 immediately. I just replaced bushings in shifter to tighten that up. It's cheap, at least for parts, $25. First tranny service was at 63K, 1st synchro then I mis-shifted and blew out 2nd gear at 82K. Then had problem at 119K. As you can imagine, this work is expensive.
3) Pre-Purchase Inspection see http://forums.rennlist.com/ under air cooled / 911 read Peter Zimmerman sticky post at the top on this. Also see http://forums.pelicanparts.com/forumdisplay.php?s=&forumid=8
4) I have a Cab. convertible. Tops last 10 years but are $2000 installed + 700 extra pounds in stiffning. Go hardtop as you say.
5) Misc. maintenance. Brakes wear like any other. I like Hawk/EBC race style and/or ceramic street pads, they last a long time. Valve adj. is recommended every 15K, I do about 60K. Plugs every 2 years, I just changed them after 5 and had one break on me. Tires I have best luck with BF Goodrich, right now Traction T/A ($100/), and have been getting 45-53K miles. This is my 3rd set. A friend spends $400/tire and get 11K on a '90's 911. See www.Tirerack.com I replaced my first CV joint yesterday, they were never repacked.
6) I would also avoid a car with modifications. This generally makes it less reliable and harder to service.
After personally putting on almost 160K miles on my 1985 (now at 175k) I think I'm qualified to answer this question.
Overall this car is probably the most reliable vehicle I've owned, it has NEVER left me stranded. Early on I left maintenance to a local shop but in the last six years I have done all of it.
Here are my specific comments in no priority.
1) Oil changes. I would look for records and do 3000 miles with 20W50 (unless cold climate) using Mahle OC-54 filter. This engine has brass valve guides that wear and oil consumption is high (600-1000 miles/qt is typical even in 90's models) Takes 12 quarts, has two drain plugs. Try to determine oil consumption. You could also check valve guide wear by having owner drive on highway/accelerate and then back off, look for smoke. I have not had my valve guides replaced even my mileage and get ~1000 miles/ qt. and I did 7500 mile changes until about 110K.
2) It has a porsche design 915 transmission used in '74-86. It's the weak spot, I believe, on the car. The G50 tranny (Brog Warner?) was in 1987. The 915 has brass syncro's that don't like synthetic fluid. Check service records but probably just change tanny fluid to Swepco 901 immediately. I just replaced bushings in shifter to tighten that up. It's cheap, at least for parts, $25. First tranny service was at 63K, 1st synchro then I mis-shifted and blew out 2nd gear at 82K. Then had problem at 119K. As you can imagine, this work is expensive.
3) Pre-Purchase Inspection see http://forums.rennlist.com/ under air cooled / 911 read Peter Zimmerman sticky post at the top on this. Also see http://forums.pelicanparts.com/forumdisplay.php?s=&forumid=8
4) I have a Cab. convertible. Tops last 10 years but are $2000 installed + 700 extra pounds in stiffning. Go hardtop as you say.
5) Misc. maintenance. Brakes wear like any other. I like Hawk/EBC race style and/or ceramic street pads, they last a long time. Valve adj. is recommended every 15K, I do about 60K. Plugs every 2 years, I just changed them after 5 and had one break on me. Tires I have best luck with BF Goodrich, right now Traction T/A ($100/), and have been getting 45-53K miles. This is my 3rd set. A friend spends $400/tire and get 11K on a '90's 911. See www.Tirerack.com I replaced my first CV joint yesterday, they were never repacked.
6) I would also avoid a car with modifications. This generally makes it less reliable and harder to service.
Frag_dude
07-26-2007, 02:20 AM
I agree, I have a 1987 911. It is pretty similar to a 1985, but as stated has the g50 transmission (by Getrag). If the car is serviced at the proper intervals these things will last a very long time. But there is a downside, if anything major has to be redone it an cost a lot of money. So look for a car with a good service history.
As far as modifications making the car a worse example, I wouldn't go as far as to say that. I bought mine with a different exhaust and an intake lid. Not exactly huge changes but free up a pit of power and give it a nicer rumble.
As far as modifications making the car a worse example, I wouldn't go as far as to say that. I bought mine with a different exhaust and an intake lid. Not exactly huge changes but free up a pit of power and give it a nicer rumble.
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