any one go an idea of about how long my engine will last. it has 155k miles and only has 60 psi compressio on front and rear roto and it is an s5 na

 

It can blow at any moment.

 

yeah might as well just start saving for a rebuild

 

Tear it down and rebuild it now. If you wait and see how long you can milk it, you probably will need a rotor and or housing when it finally blows (assuming you don't already need em).

 

Did you use a rotary compression tester?

 

use a borescope on your engine thru the spark plug holes and look at your housings. any comaptent shop should do it for at little as 45. if you want to inspect your housings, you likely have a alot of wear, and a possible gouge.

 

i figured that. i used a regular piston type comprssion tester and it was 3 evern bounces of 60 psi on both rotors. it starts and runs fine so far but i only have about half thmoney to rebuild it thats why im asking

 

Get a rotary compression tester. I'm pretty sure piston testers give fucked up readings. Also make sure the throttle is wide upen when you test and RPM's are around 250.

 

you could get away with 200 to build your motor now, if you did it all your self.
and maybe it will last 70to100k more after a 200 dollar budge build.

 

were could you get the gaskets to build it for 200 th chepest i could find was 800 or more and that was with out apex seals and if i did it or 200 could i drive it hard or just get from a to b

 

do it now, and you can get by on probably 600, but I would do a tad more and replace oil and coolant seals while you're in there. Do it right and get another 155k out of it. Congrats, that's the second highest mileage I've seen a rotary last (although I'm sure there are others out there)

 

Did you just suggest to him to do a $200 budget build?

 

i have 750 i can spend now but i dont know where to get the parts that cheap

 

http://rotaryaviation.com/o-ring_kits.htm171 SHIPPED.
i can get apex seals locally cheap, and housings for next to nothing , but it's all 100k plus mile stuff, except the seals are all 7.8-.0mm.
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Failed to see Rotor housings on this list, which will be require for more then about 100k on already 155k miles housings, which is exactly the reason for a cheap rebuild.

 

It would require a skillful art of not breaking old gaskets and getting them off in one peice.. or if all else fails, some Black RTV, for the oil pan, get or make a front cover gasket, dont use RTV there, or on the water pump to block gasket, those are super easy to cut out.

i would drive it like normal, rev the **** out of it, but dont let it over heat.

This is AFTER i see the housings on the inside FIRST, before i ever tare down the block. you need to make sure an apex seal hasnt damaged the housing super badly, i had a motor with 165k miles, 115 psi compression. and the apex seals were right at 6.52, so maybe had 2k miles left on them..but the motor needed a new coolant seal. now they've got about 26k more with new(used) apex seals.

 

Um, back up a second here.

There are two things to do when you're using a piston tester. When you do the part that you did, you are *only* looking for 3 even sweeps/bounces. You are not using the height of those bounces to measure the compression because the schraeder valve is venting the whole time.

The second part is to crank with that valve closed. That's when you're judging compression.

Did you do part two, or are you going solely by part one? If you only did part one, all you can say right now is that things are looking good.

 

no they won't, if it specs out then they're still reusable, unless there's something different with second gens that I don't know. and that's a damn good price IMO.

 

He has a reallllly good point here. When i read 60PSI i assumed total psi and said it can blow at any moment. Thinking about it now that would basically mean its already blown if total psi was 60. DOH

To the OP report back to us with a comp test with the valves installed/closed. I know my S4 n/a engine is STRONG and i only did a comp test with the valve open getting 60+PSI. If you aren't having any starting issues or smoke issues i'd assume the core is good.

P.S I laughed pretty hard at the $200 rebuild.

 

just for referrence, my cousin just cracked 220k on his stock base 87 FC, no rebuild, but about a hundred clutches and sets of tirs

 

why do noobs say this? low compression does not mean an engine is going to blow up, it simply means your housings and seals are probably worn and it will just continue to become more difficult to start as compression gets lower.


you can't. there is no such thing as a "budget rebuild" on an engine that has that low of compression and worn apex seals. i do suspect you used the gauge wrong though since it would be near impossible to start an engine reliably that only has 60PSI of compression.

 

i dont know if the gauge is wrong or not but when i didnt pull the valve it didnt build mo than 60 psi and wen it was bouncing it hit 55 o 60 all three times
it my daily and ther only car i have now thats only reason im nervous about it

 

You have to leave the valve closed to get the near true compression. The bounce test is only to show how even the comparative compression is between rotor faces. You could have a motor that's actually holding 100psi+ compression. http://rotaryresurrection.com/2ndgen...ion_check.html

 

Being nervous does you no good...it's decision time.

Seems to me that you have two immediate options:
- If it does in fact "drive fine", just keep driving it until it doesn't.
My NA had 80psi when I bought it three years ago but ran- and continues to run- quite well. Never floods or fails to start, gets reasonable gas mileage...seems fine.
I've put over 50K miles on her since then (she's my only car, too) and have had zero engine related problems.

-Start proactively planning for an engine swap.
By "swap" I mean either another rebuilt NA, a turbo conversion or a different engine altogether.
You'll have to decide which path makes the most sense for you, my thinking tends towards either a rebuilt NA or a V-8, the turbo is really not a viable option IMO.

Option one is obviously the riskiest but unless the engine just decides to pop- always a possibility- you should have fair warning that things are really beginning to deteriorate.
Option two is the smartest but requires that you immediately start spending money acquiring parts. Giving yourself a few months to get ready means that you can shop around and not jump on whatever happens to be available right then.

Either way, good luck.

 

i want to rebuild with a street port, and i also i have never rebuilt a rotary i have done practicley everytihng else but rebuilt one, or i can find one thats already been rebuilt that can afford i will do that and it woul be easier for me because it is my daily andi could swap it in a day

 

Did you make sure that you had the throttle wide open, when doing the compression check?