I've got an '89 GXL with a 13b, the vehicle has sat for approximately 5 years, and it has 202,000mi on the odometer ( I dont know if the engine is original ). The engine cranks over easily, although i've yet to check compression. It will start on it's own and run for approximately 5 seconds. On alternative fuel it will run for 10 seconds, continuing to add fuel has no effect, same with pumping the gas pedal. The exhaust pours out white smoke, prior to changine the oil it was literally leaking oil out before the cat. I have replaced the fuel pump, fuel filter, spark plugs ( NGK, i did double check that they're in the right position ), and changed the oil with 10w40. The spark plugs were fouled and the fuel had turned into varnish so i had to replace the pump and filter. I was wondering if anyone's had a similar problem, i'm new to rotary and was hoping someone might have a good idea where to start. Thanks in advance.

 

An update from last night. I performed the clear flood procedure twice and made some progress. The engine ran for about 2 minutes, i had to keep the throttle on or it would stall out. It's still smoking very badly, but doesn't seem to be using a lot of oil. What concerns me is that after starting and stalling for about an hour the cat was glowing. I've been searching but can't find a backpressure specification. I'm not sure if it's getting so hot because of fuel and oil entering it or because of a blockage. I dropped the exhaust after the manifold and it fired right up, but still didn't want to stay running. I thought i read somewhere on this site that the rotary's need some backpressure to run, if anyone knows how much or the truth of it it'd be extremly helpful.

 

Finally made some progress, found that if i hold the maf open slightly, it'll run. Using a screw driver to hold it open it idled aslong as i let it. It's still smoking a lot, it seems to all be fuel. Reading through a diag chart i found that the maf controls the fuel pump when it's not being cranked. Hence my issue with it running for only 10 seconds. Im hopeing that with a new maf it'll stop putting so much fuel in, otherwise i think i may have leaking injectors.

 

Update from the weekend. Drove it it finally. Still lots of smoke and won't idle with the maf at the normal position. Found a test procedure for it and it passed in spec. Took the intkate off to check injectors. The inlet screens were clean and the pintles felt liked they moved freely. The fuel in the rails was milky. Double checked in the tank and the fuel is contaminated. Seems like fuels beeen my problem all along, now i'm gonna try tracking down a tank or somewhere local who'll chean and reseal it.

 

Have you verified that the leading (lower) spark plugs are sparking? That is always my first thought when I hear about a glowing cat or header. When that happens, only the trailing (late firing) plugs fire the fuel mixture, and it happens so late in the cycle that most of the flame goes straight into the exhaust. This results in low power, rough idle (if it will idle at all) and an overheated exhaust system.

Radiator shops will usually boil and seal a gas tank for 50 bucks or so.

Best of luck.




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I did verify spark on all cylinders, but with the exhaust loaded up with watered down fuel i'm left to assume that the cat loaded up and it started to burn as it heated up. Unfortunately, i'm deep in GM territory and most places around here dont want to touch it. I do have a line on 2 tanks near detroit, i'll know for sure tomorrow. Also, prior to replacing the pump i dropped the tank and cleaned it with degreaser inside and out, let it dry out, and did a final rinse with a gallon of known good gas. I appreciate the advice.

 

A local club for local help:

http://www.michiganrotaryclub.com/index.php

 

Awesome, I don't see many rx's around here. I didn't even know that there was a michigan club lol. I really appreciate it

 

No problem. Once you find out where we are hiding, you'll find we're a pretty tight knit bunch of guys. We usually have a few meets each year around Lansing (centrally located).

A lot of us are also Autocrossers, so if you have any interest in some safe racing, you've come to the right place. Looking forward to meeting you at one of the gatherings.

 

I think i took it a step backwards last night. Tried to hook it up to a S10 fuel tank and pump ( to run on alternate fuel ) and either the pump put out too much pressure or my regulator/injectors are leaking because the exhaust was dripping fuel and it flooded out almost the second i tried to start it.

 

1st find the FSM (factory Service Manual) you can find the link in the 2nd Gen faq's section

2nd check fuel... pull the fuel line and verify that you have both fuel volume and fuel pressure - there is a jumper on the passenger strut tower to jump the fuel pump

3rd check that it is actually gas and not a glutenous turpentine mess

4th pull the plugs and verify that they are not fouled or otherwise worn out

5th check timing

6th check compression, the hillbilly way is to get a compression tester with a schrader valve ... remove the valve and observe the needle bouncing... you should have 3 solid bounces per a rotor

7th remove the plugs spray a bunch of brake cleaner in the motor and crank it over like you would to de-foul a motor...MAKE SURE YOU DISCONNECT THE CAS so that you dont ignite a gas bomb in your face the idea is to clean the inside of the motor of any oil that may foul the plugs...

8th make sure you have a good battery and the battery cables are in good condition

9th check all your fuses

10th do a visual on all wire connectors

11th do a visual on nuts and bolts

12th visual on vacuum lines

other than all that, you will need to check fuel pressure and that the injectors are not clogged or burnt out

all you need for a motor to run is air/fuel spark/timing and compression

as for the s10 fuel pump, most fuel systems all run about the same pressure, if you have excessive fuel in your exhaust you probably have leaky injectors


if you can get it running, just hold it at 3-4k RPM for a while till it clears out, it aint going to break anything that aint already broke.

once it is running, you can check for vacuum leaks

sorry if this all a bit random, but i only had a couple minutes to post this

 

I finally got back to it, I did the compression test the hillbilly way, unfortunately I have no access to the proper compression guage. I got approximately 45 and 40 on the rotors. I know the minimum spec is 85 psi with a variance of 21 psi, but how far should that spec change doing it with a standard guage? My assumption at this point is that I need an engine/ rebuild. On the other hand I do have 3 consistant bounces per rotor.

 

get it sorted and do the seafoam treatment to it and see what it does after that, a good drive to clean it out might suprize you. good luck

 

As long as you have even pulses, I wouldn't worry too much about the numbers. A flooded rotary will show low or no compression. You might have to pull start it to get it going again.

I fought a flooding issue for a few days last month. Even though I had spark on the leading, when I replaced that coil (because there was nothing else to try) she fired right up. So sometimes spark is not good enough, you have to have very good spark.