praveen

I rebuilt my 3rd generation twinturbo with new rotors, housings and kits. Now i jsut cant start....ive got spark, fuel pump pressure, fuel delivery to primary injectors. ive even got the flooding problem under control by connecting/disconnecting the pump. I keep defouling the plugs. The engine fired once or twice but thats it.
However compression is improving after one whole day of cranking....should ikeep on going, cranking away? hoping that itll start when it reaches adequate compression..? or can someone whose had the same problem help me....id really appreciate it.

wylie

Well I'm in a similar predicament right now.

One thing that a very reputable rotary mechanic suggested was pull starting. I personally don't like the idea but he swore by it. It didn't work for me but maybe you'll have better luck. If you have a stock fuel setup put a inline pressure gauge to see if you get adequete pressure. This link has manuals that will help.
http://iluvmyrx7.com/
Follow troubleshooting procedures and good luck. Also off the top pf my head make sure the crank sensors are not backwards (the white connector goes on top)

Keep posting progress.

T.W.

SVT Squasher

Sorry Im not to familer with the rotory motor but I am trying to learn myself. V8 I know alot about. Compression in theroy should be there now. Compression should not get greater the longer you crank it. Did you pre lube the motor as you built it? When your cranking it can you see your oil pressure move, this should be your main consern right now, you dont want to run it without oil pressure and the same gose for prolong cranking. Now for why it wont fire? In theroy all you you ned for a internal combustion motor to run is fuel, compression, & spark. What they dont tell you is that you have to have the timing some what close. I dont know how to set the timing on the rotory but it sounds to me like that might be your brop if you have the the other three.
I hope I helped you out or gave you a place to trouble shoot. Like I said tho Im not very good rotory's yet.
Good luck......

Snook

iTrader: (12)

yeah race engines with 1 piece seals always have to be pushstarted

i dont think the lack of compression is the problem I've seen cars with 130k miles start it just takes a while.

put in a good amount of ATF through the lim, reset the ecu, dry plugs and try again. If you are getting fuel pressure I guess all 3 of your fuel lines are correct?

ERAUMAZDA

Pushstarted? Just poor some MMO in motor and that would help seal it up and it sould start. Cranking it over and over damages toyr starter and could screw up the bearings from oil starvation.

silver93

3 words for you:
crank angle sensor -
check 'em- they're probably backwards

praveen

i am gonna try the ATF in the lower plug chambers. I introduced engine oil there before.also i used engine oil in the assembly. but never ATF up to now. hope it works.

crank angle sensors-ill try swapping the connectors...
but thats all i can do right? timing is automatic caus there is no alignment adjustment etc for the CAS>

i tried towing once....but it really floods badly so much so that there is fuel pouring out of the tailpipe...how can i do this towing and still control the fuel..do i need a switch for the pump or will holding the gas pedal down do the trick? pls let me know the detailed procedure for towing.

thanks guys

silver93

well, when i tried starting my rebuild, it would crank but not start. i was getting fuel, spark,e tc....
on a buddy's suggestion, we switched the connectors on the sensors, and she started right up. - all you can do is switch them.

Fd3BOOST

iTrader: (7)

Kick the tires

Snook

iTrader: (12)

I always thought the 2 CASs were the same
So I guess the connectors on them just need to be in a certain order for one to recieve a signel first.

Any way, you'll figure it out real soon it sounds like cause there isn't much else that could be wrong.

turbojeff

iTrader: (30)

The white connector goes to the CAS on top.

Push starting/pull starting is a good way to get the cranking revs up. Many times the compression is low on a rebuild before it is started and plugs get fouled with gas and prelube.

Sometimes it helps to just jump it even if it seems like it is cranking fast enough.

praveen

Tried starting the car the whole of today. Introduced ATF into the sparkplug chambers, checked the CAS connectors....no luck. im kjsut not geting enough compression. I guess the seals are refusing to sit right and give proper compression...should i jsut keep on cranking or tow? will i damage the rotors and housings if i tow? or will the heat and friction caused by the towing cause the seals to seat properly?

any ideas guys?

praveen

Finally figured out what was wrong....i didnt replace the side rotor housings,,,only the main aluminium ones,,,,and they were slighty warped////so the seals were not sitting properly and so not enough compression.....
lesson...if youre gonna do a rebuild on a blown motor, make sure all the housings are level to specs....

got a new engine and am rolling again,,,feels good...as long as i dont think about the cost!

vosko

iTrader: (4)

hmmm pays to double check things!