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Another blown engine thread

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Old 04-30-15, 11:01 AM
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Another blown engine thread

Hello, Have Some questions are new in rotarys but want to Do Rebuild for myself. But its Little Strange today i had done compressiontest with normal engine tester And had even bounces, but only up to 3-4 Psi on rear rotor. But The car has more power then my friends fd that Has in Both rotors 6psi could this be normal or can that car be flooded? When i start her it smells realy hard And i Have teary eyes And stalling Problems also, but very intermittend. It dies not always sometimes it idles very well. Under load The car has so much power to keep up with new Porsches. Can that be with a low comp engine or can The reading of only 40 Psi caused By other things? And i Have Never Seen black smoke, thought when a seal Broke or low compression is it will smoke. It Smokes only white but think Thats because it runs to Rich?.there is no lost of water. Spark plugs from rear rotor And front looked The same Both black. Car has some hotstart problems but not all The time sometimes it Starts good hot. I Have read here a lot but wanted to ask you this here before i pull The engine And The engine is possibly Fine, but dont know.
Car is an fd from 94, And had a rebuild before 5000 Miles from previous owner
Wish you guys Great Weekend
Michael

Last edited by Gokuracho; 04-30-15 at 11:08 AM.
Old 04-30-15, 01:40 PM
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welcome to the board, Michael.

honestly, your narrative is a little hard to follow. i'm not poking fun at you, but for example, your compression numbers are all over the place. i don't know if they're actual numbers or typos. could you please go over the procedure you used to test the compression for us/me?

what i have gathered is:

1. the engine still starts and runs, but sometimes has a hot-start issue
2. when it doesn't stall out, it idles fine
3. it idles rich
4. you're still able to make decent-to-good power

is all of that accurate?

has the car been modified at all (fuel, EMS, etc.)?
Old 04-30-15, 01:55 PM
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It seems like it is also smoking white as well Diabolical.

When do you see that smoke and how heavy is the smoke? Is it only on startup and it goes away once it has warmed up? Do you see it only cruising or wide open throttle? If you are not noticing a loss of coolant, check your oil level and make sure that is staying pretty consistant to the amount of oil you lose to your oil metering pump.

I will also poke in as well. With FDs, black smoke is not necessarilly a bad thing. Black smoke is normally Fuel (running rich), Whiteish Gray smoke (Smells terrible almost like rotten eggs) is Oil, Whiteish Blue smoke (Smells sweet) is coolant. It also could be condensation steaming off out of the exhaust if it looks more like steam than smoke.

Last edited by RobertC; 04-30-15 at 01:58 PM. Reason: Addition
Old 04-30-15, 01:59 PM
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Originally Posted by Gokuracho
i had done compressiontest with normal engine tester And had even bounces, but only up to 3-4 Psi on rear rotor. But The car has more power then my friends fd that Has in Both rotors 6psi
Do you mean 6 bar? Theres no way a rotary engine can run on 3-4 psi or 6psi...

Originally Posted by Gokuracho
could this be normal or can that car be flooded? When i start her it smells realy hard And i Have teary eyes And stalling Problems also, but very intermittend. It dies not always sometimes it idles very well. Under load The car has so much power to keep up with new Porsches. Can that be with a low comp engine or can The reading of only 40 Psi caused By other things?
Sounds like its running rich, could be due to a lot of things. I'd check for a vacuum leak first.


Originally Posted by Gokuracho
And i Have Never Seen black smoke, thought when a seal Broke or low compression is it will smoke. It Smokes only white but think Thats because it runs to Rich?.there is no lost of water. Spark plugs from rear rotor And front looked The same Both black. Car has some hotstart problems but not all The time sometimes it Starts good hot. I Have read here a lot but wanted to ask you this here before i pull The engine And The engine is possibly Fine, but dont know.
Car is an fd from 94, And had a rebuild before 5000 Miles from previous owner
Wish you guys Great Weekend
Michael
Black smoke means fuel. Again sounds rich. List your mods.
Old 04-30-15, 02:16 PM
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Hello thank You all for your fast answer,
Sorry mean 4 bar, on The backrotor. The white smoke appears After starting in the Morning or sometimes when it is warm And Stalls when i Park it .when i keep mY Food on throttle it stays on but sometimes when it Stalls it Sounds like its Running on One rotor, had this 2 Times. Stalling is very often And annoying. But when the car is driven under load And everything is Fine. When it Hits the redline sometimes a smoke dust appears. When rpms go Down it sometimes Kind a Shakes.
It Has more power as my Friends 96 fd. A mechanic Said to me when compression is Bad there should be no Power, but it is extremely fast.
Mod List:
Tanabe exhaust, Hks downpipe, Blitz chipped ecu, Bigger injectors, dont know the Size is that Important? Exedy Stage 2 clutch, Stock twins, And Open intake from hks
Michael
Old 04-30-15, 02:17 PM
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Originally Posted by Hazel324
It seems like it is also smoking white as well Diabolical.
yes, thanks Hazel324.

Originally Posted by diabolical1
what i have gathered is:

1. the engine still starts and runs, but sometimes has a hot-start issue
2. when it doesn't stall out, it idles fine
3. it idles rich
4. you're still able to make decent-to-good power
5. you get white smoke, and you specified no black smoke.
EDIT:
Originally Posted by Gokuracho
Mod List:
Tanabe exhaust, Hks downpipe, Blitz chipped ecu, Bigger injectors, dont know the Size is that Important? Exedy Stage 2 clutch, Stock twins, And Open intake from hks
Michael
yes, the size of the injectors is important. however, you should be more concerned with the 4 bar compression right now. seals may be getting intermittently stuck for some reason. that would provide a possible explanation for why you still seem to get power and at good idle at times, but not others. either way, yes, a rebuild is probably on your horizon.

Last edited by diabolical1; 04-30-15 at 02:29 PM.
Old 04-30-15, 02:26 PM
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The engine Starts cold Fine After Long Ride it Needs 15 sec to Start then always hotstartprobs but its a 94 thought it could be electrical.
It Stalls often At traffic lights but not always sometimes it idles good but then At 1000-1100rpm

But it Has all His Power Potential on warm engine And no stumble or anything
With white smoke i mean it stinks like fuel After starting when stalling. There is no Black smoke only a dust Cloud when it Hits redline

Last edited by Gokuracho; 04-30-15 at 02:30 PM.
Old 04-30-15, 02:35 PM
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Sizing could be important for the injectors. But if the ecu was tuned with those injectors in place it should be fine there and not be as important as if you just switched to larger injectors. Do you know if only the secondary injectors are bigger and it has the factory 550cc primaries or are both larger?

4 bar is roughly 58 psi.
Old 04-30-15, 02:40 PM
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by any chance, is the engine ported as well?

anyway, if i had to venture a guess, i would your side seals are where the issue is. however, i say that with significant uncertainty.

the fuel smell you're getting when you start it after it stalls is probably because it's flooding at that point. keep in mind that this is assuming there is no other problem like the Blitz ECU and/or the injectors - which may or may not be the case.
Old 04-30-15, 02:48 PM
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Okay, i asked the previous owner for the injectors And If its ported. I will report. Last Chance before Rebuild. Wish you guys good weekend And thanks for reply
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