Hi all,

I will be opening a freshly rebuilt engine with 5,000kms, what needs to be replaced?

I was thinking I would just replaced all rubber components ie all O-rings/ Water Seals and also all gaskets.

Cheers Elliot

 

Who rebuilt it before? Was this a brand new block?

 

New housings, the face plates were lapped, all new bearings, springs and seals.

 

Why does it need to be opened? Porting it?

 

Rear housing has sub 43psi on all 3 seals for the second time in a row. I paid a shop that has been in business for over 20 years to do the first 2 builds. I want to take it some where else now.

I also want to purchase all the required parts to be installed so I have piece of mind. I don't want any corners cut or inferior parts used.

 

Then you need to just do a full rebuild. Replacing only the coolant seals and o-rings is not going to effect compression.

 

which apex seals? examine them carefully--- i'll bet they're warped if non-oem seals.

Have you been monitoring EGT and AFRs on your setup? I remember your thread detailing all your problems.

You can have the best built engine in the world, and if your spark timing or AFRs are off then you'll continue to have these problems unfortunately.

 

Its not the buider, the problem is in one of the external components of the engine or the tune. I think you are looking in the wrong direction if you believe the builder was at fault....unless they are the tuner as well.

 

Find the issue and replace ALL the seals and springs. If you are losing compression like that something is causing the seals to warp or wear prematurely. Springs that are overheated will also sag if reused. If I had to guess I'm betting you have an issue with your tune or the lapping of the irons.

 

Yeah sorry, I have the new apex seals already. I should have added that. I was just thinking about the rest of the engine.

The seals have bowed from excessive heat which would be from leaning of fuel or lack of oil.

 

I was monitoring the AFR but didn't get my 2x egts installed in time for the last engine....

 

The engine builder is also the tuner, I even swapped my ecu for one he was familiar with.
I have changed my omp for a reconditioned one, changed the omp lines for new ones.

 

Well youwouldn't be the first person to go lean in the rear on a new rebuild. Maybe everything was re-used fromthe first rebuild.. Did you check compression before the engine lost compression? or was it rebuilt and immediately had low compression?

 

It was tested 100kms after the second rebuild, it had 90-90-90Psi. I then completed the rest of the 1200km run in period. Then did 4 laps at a track whereby it then wouldn't hold idle. Tested the rear chamber, the compression tester didn't pick up a reading. Meaning it had less than 43psi.

You can hear it losing compression, the sound of the idle greatly changes and becomes unstable. It was once I started hitting boost that it shat it self.

 

Were you fully instrumented before lapping?
How were the temperatures: water, oil, exhaust?
Tune verified before tracking? AFR's, % injector duty, etc.
Bummer - here's to hoping it gets a top notch build, tune, and brake in next time.

 

Whats fully instrumented?
My oil and water temps have been ok, a little on the high side at the track water peaked at 110c and Oil peaked at 115c. My EGT wasn't installed at the time.
Tune was 100% verified, I got it tuned the day before my track session. AFR's under boost are between 11-12.
The mechanic that built my car engine twice.... only works on rotaries and has been in the game for 20+ years. He built and raced his FD at the Nurburg 12hr twice. He was even involved with the design of the ecu I am using (Adaptronic).
So it just doesn't make sense!