Hello,

just wanted to talk about my engine (87 NA 6 port with 130k Kms) which is currently blown in many ways
and is still in service and running
I find it amazing that this rotary engine still does start and drives everyday.

I will swap it out as soon as the spare engine I am building will be done. But for the time being it will be kept running.

The engine in question has a blown coolant seal and most likely a fissure in one of the oil control ring inserts.
Of course it has the obligatory low compression figures. (Would need to check for recent numbers, last year it was in the mid 80s)

So what keeps it running ?

I (carefully) release the pressurized air in the coolant system after engine shutdown so it doesn't get pushed to the chambers and smokes the hell out of the block.

I use NGK BUE surface discharge plugs. The stockers cannot keep up on the low comp (sometimes flooded) motor when cranking for a longer time.
In fact with stock plugs it does not even sputter to start. BUEs all the way and it does at least try to start. Usually it does fire up after about 3 seconds.
If not, carefully accelerator work will get it up and running after a few seconds more or when worse comes to worse one or 2 minutes.

If its reaaaally cold and it does really not want to start at all (10 minutes + of cranking), I pop the hood open and remove one of the small nippels (1 per rotor)
between the secondary injectors on the manifold and spray some WD40 or MOS2 in there for like 5 seconds. Ideally I to do both rotors for maximum effect.
The oil goes down into the primary ports. Easier than removing plugs. The result is amazing, it does start immediatly when turning the key

Thats my key to firing up an old and tired low compression engine. You might give it a try if your engine says, engough is enough

 

got you beat, my old engine in my 88 had all of 60 psi per face and it didn't have any oil or coolant sealing issues. just tired and it ran for 2 years like that, ran hard btw.
With careful throttle playing it would start 90% of the time, if not my fuel cutoff would get it going.
Plus it never blew up. I still have it and keep it lubricated for a future rebuild.

 

Thats great ! 60 psi is a really low number, surprising that it still started. Carefully throttle application is the way to go, but it doesnt work always. How do you do it ?

I made a test, using an old FC corner seal and spring, clean and lubricated corner seal slot the seal would stand out about 0,8 to 1 mm. With a used FD corner seal spring it was around 2 mm. Spring pressure on the FD spring was way stronger. I suppose having 4 of these sealing a chamber plus 2 apexes and side seals all of them with weak springs, yes that may ruin the day Those NAs just wear out, and all they need is an inspection, cleanup and new seals & springs and they are ready to go.

All of the blown engines I have seen so far were FI ones, (minus one renesis which burned up due to low oil level ...)

 

I have low comp in both of my t2 engines, I just park my car across the street facing down hill haha

 

i ran an old '89 GXL that i got for free for about 4 years with a blown motor. when i got it the seals were all stuck from rust in the chambers, pumped MMO into it and fired it up. drained the coolant and added distilled water and copper block seal and it ran just fine for that time, even made the hills all the way to vegas where about 4 months later the engine couldn't take it anymore. good thing it never gets cold enough to freeze the block out here in california and the nevada desert... so the series 5 n/a block should survive to fight another day.

i drained the block and it starts and runs fine while i move it around, waiting for the engine built on the stand to be installed. there's lots of little tricks you can use to limp a failing engine around for a while, but it is still doing harm and be sure you have a spare motor you are building versus expecting much from the original. i'm sure the GXL has numerous iron fractures by now.

i've torn down a few that had 4 and even 5 broken seal walls.

 

Thanks RotaryEvolution,

yes, these tricks come very handy to extend the MTBO a bit
The spare motor has a damaged wall too, its not broken but has chipped about 0,5 mm on one wall. Will replace the iron because I broke one of the upper tranny mountings with the flywheel stop ...

I guess that the seals are just worn and the springs weak, thats why it does not start the normal way.
After that there is the blown seal or wall (dont' know yet) which leads to the smoking and can worsen the startup sequence with water in the chambers.

Generally I pay attention that the coolant pressure is vented right after shutdown and no water enters.

But hell, yes it does pull strong when I am pushing it hard (late for work) redline all day anyways. And occasional high speed runs.
And then there is the occasional porsche on the twists who glues on my tail and needs a lesson

I am cleaning up parts for the spare motor, it would have alredy been done if there wasn't my na race engine which got delivered few weeks ago and gets all my attention
Oh btw I need to get in touch with you for one of these OMP line sets for said engine ...

 

better get em before i run out of fittings again.. difficult to keep them in stock but i have enough for 6FD/3FC engines at the moment and have a spare n/a set ready to go in clear. still trying to find some alternative fittings, but the price will go up a chunk if that is the only alternative to finding good OEM line ends. the set i found that wouldn't fit was about $50 additional for the new hardware.

 

Thanks,

yes, will order them asap as I need them, if you want to PM me your address, I will send you my set of S4 NA connectors.
I just mailed a friend of me who hopefully still has his old set for S5 T2, with a bit of chance I can make it 2 sets

Steven