So I got my TII two weeks ago, the engine was supposedly rebuilt and street ported between 2,000 - 3,000 miles ago and everything seemed fine except for a hot start problem (which after doing some forum research I had attributed to leaky injecotrs or something of the like). It would start fine cold, but once it got hot...I had to push start it (waiting might have helped, but I never had the patience, and I kept a friend w/ me )

I took it too my mechanic for a check up before I left town and he tried some new injectors but apparently the problem is being caused by weak seal springs not injectors . He said that they (the springs) work fine when cold, but lose their "springyness" after they get warm thus causing low compression aka no start. Is this common?

When he did a compression test it showed 60psi across both rotors. I know this is too low, but isn't it odd that they would have the same low compression? Also I'm assuming that this is occurring outside of the "break in period" for a rebuilt motor, so that couldn't have anything to do with the low compression could it? I just don't wanna believe that it could have been that shitty a rebuild to need an overhaul when it's barely out of the break in. What else could it be ?!?!?!?!
Plus, @ $1500 a rebuild is no drop in the bucket.

Any ideas on what else to check would be greatly appreciated.

P.S.- sorry for the long post, just tryin to be informative.

 

did they use RA seals when they did the rebuild?

 

well that seems low, but I ask:

What proof did the seller have that the motor was rebuilt X number of miles ago? are there apparent signs of a recent rebuild? i.e. freshly painted/not even dirty keg, etc?

 

Good point, the RA springs are known for flattening out correct?

 

It does look like a fresh rebuild (freshly painted motor alternating red and silver housings) The engine bay was also repainted and still looks clean.

I do not know what kind of seals were used for the rebuild, I'm trying to call the guy to find out. Is there a problem w/ RA seals/springs? Because if in fact I need a rebuild, I certainly wouldn't want to use them if there is.

 

Same thing happened to a local customer. Bought an rx7 with a " rebuilt ported " engine. @ 6k miles 60psi across both faces and hot starting problems. We opened the engine and the corner seal to sideseal clearance was .090". Nothing but the apex seals and springs had been replaced. Another half assed rebuild.

As far as the RA springs go, I built a t2 engine 2 years ago with that RA combo, its still running with the same compression, 1 bar wot everyday. However I do know some guys in Japan that measured the RA apex seal springs flattening over time..

 

well as far as i know they do not take well to heat or running lean.

 

This is not good. It looks like it's rebuild time If the rebuild was that shitty, I'm prolly gonna need to have the port job inspected/ redone as well. Definitely gonna have a little chat w/ the PO.

Since "heat" seems to be found in spades inside a rotary engine, what springs/seals (other than RA) would you reccomend? Can't have another half-assed rebuild.

 

atkins

 

or OEM

 

Thanks for the info, I'll make sure to use those. Also, what benefit is there to using 3mm as opposed to 2mm seals? engine life? compression? power?

 

knock resistance....the 3mm will take more ping than the 2mm, really no big hairy deal. You can run 25+psi on 2mm mazda seals anyways....

Plus when you factor in the cost of having the rotor milled its for the most part not worth it unless you're hell bent on having them in there. But make no mistake a rotary with 3mm seals is not bullet proof.

 

I'd suggest using fd corner seal springs also.

 

Might have to have irons/housings replaced if someone didn't know what they were doing.

OEM for everything.