worth rebuilding my engine?

Silver86 · 09-06-2009, 10:45 PM

Quote:

Originally Posted by Max777

Dude, mine ran kinda crappy, the compression was low, it was only pulling about 12" of vaccum at idle, and the transmission had about 140K on it. I priced out a rebuild, and all the work/tools/time involved, and decided that unless there is some concrete reason you want to keep the N/A powerplant, a TII swap just makes more sense. Also, if a TII engine blows, there is more reason to rebuild IT, rather than the crap N/A.

good reasoning, but a TII swap is not something i want... i would rather rip out my N/a powerplant, rebuild it and re-install... thus getting a chance to enjoy the car (even if its slow) while i buy/build/prep for the 20b swap.

need RX7 · 09-06-2009, 10:52 PM

Since you're trying to save for the swap, I'd look for a known-running, low-ish mile engine and throw it in for the time being. It won't cost as much as a rebuild and it'll get you back on the road. Of course, there's always the chance that there will be something wrong with it and it will put you even deeper in the hole...

RETed · 09-07-2009, 02:05 AM

Did anyone mention doing a COMPRESSION TEST before opening the engine up???

-Ted

need RX7 · 09-07-2009, 03:04 AM

Quote:

Originally Posted by RETed

Did anyone mention doing a COMPRESSION TEST before opening the engine up???

-Ted

Yes, do this if you haven't already. I assumed it was always a given.

Phoenix7 · 09-07-2009, 03:42 AM

Quote:

Originally Posted by need RX7

Yes, do this if you haven't already. I assumed it was always a given.

me too, blown motor = compression test showed 0 psi on 1 or more rotors.

Silver86 · 09-07-2009, 02:23 PM

Quote:

Originally Posted by RETed

Did anyone mention doing a COMPRESSION TEST before opening the engine up???

-Ted

lol... im no noob Ted... of course if did a compression test. it was the first thing i did after i got the car home after buying it. its been a few years... so i might as well try it again, just to see if anythings changed. the last i did check it though... i do remember now... i did get 3 decent pulses on the front rotor... and only 2 on the rear... that was also 3 years ago.

RETed · 09-07-2009, 11:52 PM

Quote:

Originally Posted by Silver86

i did get 3 decent pulses on the front rotor... and only 2 on the rear... that was also 3 years ago.

Only 2 on the rear might mean just a stuck side seal.
Try soaking the rear rotor in ATF or MMO or whatever your fav is.
1 good and 2 bad / no pulses is indicative of a bad apex seal and guarantee a rebuild.

If it's a stuck side seal, there's a chance you could resurrect the engine without opening it up...

-Ted

Silver86 · 09-08-2009, 03:16 AM

Quote:

Originally Posted by RETed

Only 2 on the rear might mean just a stuck side seal.
Try soaking the rear rotor in ATF or MMO or whatever your fav is.
1 good and 2 bad / no pulses is indicative of a bad apex seal and guarantee a rebuild.

If it's a stuck side seal, there's a chance you could resurrect the engine without opening it up...

-Ted

how would i go about positioning that side of the rotor down so itll soak? crank the engine by hand?

err i worder that wrong... how would you do it Ted?

RETed · 09-08-2009, 01:32 PM

Yeah, crank by hand.
I typically use the 19mm bolt in the center of the main pulley.
I'll pour the liquid via a hose and funnel through the leading spark plug hole(s).
Crank just enough just to get the liquid to go through.
Don't crank it too many times, and it starts to get spit out the exhaust.
Allow to soak 24 hours or overnight.
With ATF, it should fire up.
Just be warned that ATF burning causes a HUGE SMOKE CLOUD.
It'll take a few minutes to burn off.

-Ted

09-06-2009, 10:52 PM	#2
need RX7 Clean S4 Nutswinger Join Date: Mar 2008 Location: Sterling Heights, MI Posts: 485 Rep Power: 18	Since you're trying to save for the swap, I'd look for a known-running, low-ish mile engine and throw it in for the time being. It won't cost as much as a rebuild and it'll get you back on the road. Of course, there's always the chance that there will be something wrong with it and it will put you even deeper in the hole... __________________ -Ted -1986 Mazda RX7 Sport [DD/beater]: engine finally let go at 205k. parts car status. -1986 Mazda RX7 base [resto-mod project]: S5 n/a swap in progress.