Hi folks..

Im in the middle of a rebuild, Think its just a low compression problem, Difficult to start when cold but particularly hot, Occasionally stalls at idle,

I just want to know when ive opened the engine up, what im looking for as damaged parts, ie Side seal snap/damage Rotor housings warn...

was thinking about using toughened 3mm or 3.5mm Apex seals?

 

Oh god no

Stop this stop it right now, if you don't know what to look for why would you do a rebuild yourself. I would recommend talking to a shop around your area. Knowing what ti look for and what needs to be replaced is 90% of any rebuild. Knowing tolerances and machining is the rest. Rule of thumb is bearings and all seals need to be replaced no matter what. Rotors need to be machined in order to fit 3mm seals. The rest if the parts all need thorough cleaning and inspecting in order to tell if they are reusable.

This will only end one way

 

there is no 3.5mm seal size and there is no benefit of moving up to a 3mm seal anyways.

in fact i don't think the renesis rotors can even handle 3mm seals. the seal slot will be extremely shallow by the time it is milled and you will lose the renesis corner seals.

just send it off to be rebuilt or buy a reman from the dealer and figure out how to do the engine R+R before getting up to your neck inside the engine.

 

I have 3mm seals

 

well the only reason to go bigger on the seal width is for forced induction, and even then in most cases the benefits are marginal where the penalty is heavier than the benefit.

 

Thats the plan

 

Remove all tension bolts and stationary gears. Use a rubber mallet to carefully remove one housing at a time. You want to inspect the seals on the rotor before they fall out and get lost.

Example:

Carefully remove the front iron. See what seals are on the rotor. Some might stick to the front iron due to oil residue. Make sure no seals dropped. Are any seals missing? Are any seals damaged?

Carefully remove the rotor from the rotor housing. See what seals are on the rotor. Some might stick to the center iron due to oil residue. Make sure no seals dropped. Are any seals missing? Are any seals damaged?

Continue to repeat the process for the other rotor.

Afterwards, you can inspect the housings. Doing the inspection process as you go along will make sure that the engine wasn't built with missing parts, or a seal got damaged in your workshop. You will know if a broken seal stayed in place, or if it flew around the housing or something else flew around in there via intake.

I'm not an engine builder, but that was my process in a tear down I just completed. Good luck! Make sure you have help from an experienced rebuilder so you know tolerances, what parts need replacing, endplay, etc. Rebuilding is so easy a 5 year old girl on youtube did it. However, doing things to proper spec requires knowledge. Thats why I send mine to be rebuilt. When I build a spare engine, I will tackle it myself with help from a few experienced local rebuilders.