This is my first rebuild of a rotary engine (13B PP) and I am wondering what oil should I use intially to run the engine in? and what is the procedure for running in? I've seen websites that suggest running in over two days gradually building up the revs but others who own rotary-powered race cars say this is too extreme.



Any advice/experiences would be greatly appreciated.



Peter

Use a good quality mineral oil. I know this is an old debate, but Mazda Australia released a bulletin recently in relation to RX-8's, saying they are not to have any form of synthetic in them (even blends), and likewise for the older rotaries. MA are now recommending unblended mineral oil. Enough on that for now.



Depending on what is new in your motor, if it's just apex seals then a few hundred k's of light driving should be fine (I know it's a PP, but try to keep the revs below 5000).



If bearings and all seals were replaced, then probably about 1000 k's should do. Just don't over-rev.



If you used second hand imperfect housings then it may take a while longer for the seals to bed in to the housing face.



The secret is not to thrash them at first. After 500 or 1000 k's replace oil and filter. Just use a good mineral oil- there are plenty to choose from.



Good luck!

Thanks Andy,



I am using new front and rear stationary gears, bearings, used rotors, used e-shaft, and all new gaskets and apex seals.



I spoke with my engine guy last night and he also recommended a good mineral oil eg. Valvoline XLD 20X-50.



Looks like I have to return my Castrol R to SuperCheap! But I can but 15 litres of XLD for the price of the 'R'. https://www.nopistons.com/forums/pub...#>/biggrin.png

Are those R5 side plates?

I don't know what the beef is with the synthetic oils, but as far as break-in is concerned a good mineral oil is recomended. But do you know why the mineral oil is recommended instead of synthetic for the break-in period?

PK797 NYC

The beef with synthetic oil is that it has been attacking the oil control seals (the rubber/silicone/neoprene whatever part) which leads to premature failure and excessive oil consumption.



Don't question me, I'm only the messenger. Mazda Australia released a technical bulletin on this very recently and I read it at Rotomotion Engineers here in Perth.



As I said, I don't want to get into a great debate into it, just passing on what I saw with my own eyes... https://www.nopistons.com/forums/pub...#>/biggrin.png

That actually looks like a '74-'75 end plate. The rotor housings also look like '74-'75, with their tiny exhaust ports enlarged a decent amount in the other thread. https://www.nopistons.com/forums/pub...IR#>/smile.png

Yes, those are R5 endplates.



You should use a good mineral oil for break-in, I exchanged the Castrol R for Valvoline XLD Plus 20W-50, which I will also use after the motor is run in.



According my engine guy the rotary engine needs to break down the oil for lubrication and cooling, and it is much harder to break down a synthetic, even a synthetic-enhanced mineral oil.



Even though most of the guys I speak to out at the track use a synthetic, I do remember reading somewhere a few years ago that synthetics were not advisable for rotary engines.



My engine guy said not to use a specific 'running-in' oil either. The Valvoline XLD Plus is more than suited to both run-in and day-to-day use, or track use, in my case.



And, yes, the engine is from the 70's. I believe it was out of an RX-5, as it came with two RX-5 gearboxes when I bought it. I have now switched to a Supra 5 speed as the two Mazda boxes weren't up to the task!



See my website, if you're interested in more details and photos:



http://users.tpg.com.au/adslljrb/index.asp https://www.nopistons.com/forums/pub...1047683473.gif



If you are interested in more engine photos, I can post later.



Regards,

Peter

A quick look around the Net yeilded the following information, which more or less, fits in with what this thread has already discussed:



"The Rotary engine has an oil injection system that injects small amounts of oil into either the intake tract, carb, or rotor housing (depending on year/model). This is needed to lubricate the various internal seals and surfaces."



furthermore,



"The Oil Metering Pump injects a deliberate amount of oil into the carburetor for the engine to burn. The nature of non-synthetic oils is that they leave a slippery residue even after the combustion process. This residue is what hangs around inside your engine to keep the Apex Seals wet. Synthetic oils burn too clean to lubricate the compression seals in a rotary."



My racing engine (13BB PP) has the OMP deleted. That is why I add 120-130mls of a good 2-stroke oil like Castol 747 (Castor) to every 20Liters of PULP fuel. https://www.nopistons.com/forums/pub...DIR#>/cool.png



I have some photos to illustrate above which I will post tonite.



Cheers

some photos as promised ...

And some photos of the R5's ...

They look good, but your intermediate port is small. I guess it doesn't matter though, with a P port. https://www.nopistons.com/forums/pub...IR#>/smile.png



I've got a set of R5 end plates and I think an N intermediate plate. All the ports are average height. Not as tall as '74-'75, but not as short as yours. Also, the outside of the intermediate plate has tall runners, like the US spec FB ('84-'85 for sure).

You're right. The manifold for the PP motor is custom made to block off those four ports. https://www.nopistons.com/forums/pub...DIR#>/wink.png



Peter

I posted a photo in the thread dealing with Peripheral Ports by Heath. Here's another of the new engine being assembled.



What opinions are there re: the placement of the two shims between the water pump housing and the water pump? The FM says to place two shims at points 2 and 4 but my original engine didn't have them, and water leaks weren't a problem.



Peter

One shim on each stud. They're good to use, but I've also seen an engine not leak without them. I got a set of new ones from Banzai for my 20B. https://www.nopistons.com/forums/pub...IR#>/smile.png

The shims are to account for the gasket thickness at all the other mounting points. Not using the shims will cause the waterpump and housing to distort a small amount when you tighten everything up. You have a killer motor, why skimp on two shims?