mazda_racer

Hi all,



As some of you might remember I rebuilt my 13B PP race engine before Christmas. Having installed it I had considerable difficulty setting up the timing due to the fitment of an aftermarket pulley. That pulley is pre-86 so it could go on any one of 4 ways. I eventually found the correct fit by trial and error over a number of weekends. I finally got the timing spot on and everything seemed to be fine.



I ran the engine on idle for about 10 mins at 2K RPM over two sessions.



The other day I came back to it, fired it up and it started for about 10 secs, then seemed to lose a rotor (which it was doing when the plugs were fouling). I checked the plugs and they seemed to be fine so I reinstalled and tried to fire it up. NOTHING! Several attempts since then have had no success.



I dropped the oil out of it and there were a few microspecs of metal which I put down to bedding in the bearings. I replaced the oil and installed a new oil filter. But still no go.



I did a quick and dirty compression test and I think the rear rotor is much lower than the front ~ 30 or so in the rear, about 70-80 in the front.



I did a check with the plug out and it gave the customary 3 puffs front and rear.



Does anybody here have any ideas on what might have happened?



Cheers,

Peter

93BlackFD

sounds fishy...what type of apex seals were you running

mazda_racer

It's got me beat - the engine is really struggling to get any revs even with a fully charged Odyssey battery!



I put in two new rotors (used, matched pair), new (used) e-shaft, new bearings adapted for racing by enlarging oil passages, new front and rear stationery gears, all new side seals, corner seals, oil seals etc and 3mm carbon apex seals, all sourced from Australia's Rotary Beat agent.



I had the end and middle plates (R5s) machined by reputable machine shop (this guy does all the high power drag rotaries around here).



Each attempt at starting drains the battery, requiring about two hours for recharge - it was doing this before when I was playing with the timing, so nothing new here.



I triple checked all clearances as this was my first rotary rebuild. I got the video and the factory manuals, as well as a Chilton's manual, to double check all figures.



Cheers,

Peter

mazdaspeed7

Does the engine spin over easily by hand?

mazda_racer

Using a halfinch ratchet drive I can turn the engine over at the pulley without much effort.



I suppose the next step is to remove the exhaust and check to see that the apex seals are all still in their grooves?



Thanks,



Peter

Fluid Dynamics

That blows!



What happens to the rear rotor when you soak it with a few ounces of ATF?

j9fd3s

it gets wet.



i think the engine needs to come apart to see whats wrong, id be looking for a damaged apex seal

banzaitoyota

Did you cut apart the old oil filter to check for metal fragments?

mazda_racer

No, but I still have it. Those suckers aren't the easiest thing in the world to cut open.



The original engine was destroyed due to spun rear bearing, thus there was a lot of fine metal in the sump when I removed it.



I dismantled the oil lines and cleaned them out thoroughly, and also flushed the oil cooler (a homeade job which looks suspiciously like something from the back of an air conditioner) three times, and I had to have it repaired as the inlet nipple was broken off. I know you're probably thinking that there was still metal in there but it is a simple device that flushed without too much difficulty.



I removed the sump yesterday and there was a very small amount of fine metal there, but again, nothing that would cause concern. Maybe I'm wrong, but I think I'll have to have a look at the apex seals through the exhaust openings



Cheers,

Peter

Jeff20B

Man that sucks. I just re-rebuilt a 13B right before Christmas that had overheated due to a bad radiator.