How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask Doug C. Your Own Question

Doug C.
Doug C., ASE Certified Technician
Category: Car
Satisfied Customers: 6182
Experience:  16 years automotive and OTR repair including specialized training from Toyota and Mitsubishi
Type Your Car Question Here...
Doug C. is online now
A new question is answered every 9 seconds

Mazda rx7: I have a 1983 mazda rx7. It takes a long time to

Resolved Question:

I have a 1983 mazda rx7. It takes a long time to start for the first time while pulling the choke. After the second attempt (about 6 seconds per attempt) while pumping the gas, it finally starts. At any time prior to the choke retracting by it self, the car will shut off unless I keep the throttle about 2000 RPMs. And after it warms up it will not start again until it cools. I recently purchased the car from someone who had it parked for a long time. It has 27,500 miles. I pulled out the spark plugs and they had particles of black soot on them. I also check for fuel flow from the pump and looks fine. How ever it does leak gas after it has been running for a couple of minutes from behind the center of the carburetor from a square plate being held by 4 Philip screws and I believe it has a spring inside. I has a portion in the center the moves along with the accelerator or choke. It

Thanks in advance,

Moustafa
Submitted: 1 year ago.
Category: Car
Expert:  Doug C. replied 1 year ago.
Hi Moustafa,

It sounds like you are going to be in the market for a new carburetor or at the least an overhaul.

The difficulty starting as well as the black sooty plugs are both indicators of over fueling. Having to keep the throttle considerably open to avoid the engine dying also supports this. Combining this with the external fuel leakage, it is time to pull that carb and have it inspected to see if it can be overhauled or if it would make more sense to replace.
You will want to shop around for a shop for this; finding someone that still works on carburetors and is efficient with them is not as easy as it was 20 years ago. You don't want someone learning/guessing at this at the expense of your wallet. It is worth the extra money a carb-specific shop will charge.
Doug C., ASE Certified Technician
Category: Car
Satisfied Customers: 6182
Experience: 16 years automotive and OTR repair including specialized training from Toyota and Mitsubishi
Doug C. and 15 other Car Specialists are ready to help you
Customer: replied 1 year ago.


Ok great thanks. I have one more concern. Could this symptom also fall under a low compression motor? I heard that if a motor is hard to start when it's warm.

Expert:  Doug C. replied 1 year ago.
Hi,

Low compression would cause difficulty starting as well as the appearance of over fueling on the plugs. Since the compression is low it would be more difficult to make combustion, so it would appear that there was too much fuel when in reality it was the right amount but just not burning. This of course would not have any impact on the external fuel leak though.

It is highly unlikely to have this issue and have it change significantly with engine temperature. Typically if your compression is low, it's low regardless of temperature.

If you wanted to test your compression first just to rule it out, you can usually rent compression testers from most parts stores or purchase one for under $50. They thread in to the spark plug holes then you just crank the engine over 4-5 times and check the gauge reading.
Minimum acceptable compression on a 2 rotor is 85 psi, but realistic compression would be more in the 100-115 range typically. 85 is just the minimum workable spec. There should not be more than 20 psi difference between any two plug holes either.

JustAnswer in the News:

 
 
 
Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
 
 
 

What Customers are Saying:

 
 
 
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
< Last | Next >
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
  • used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future. David L. Richmond, TX
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil Marysville, CA
  • Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible. Charles Walnut Creek, CA
  • As a single woman, I really appreciate an excellent and affordable opinion.
    Thank you Geordie, I will not hesitate to contact justanswer in the future!
    Sue Charleston, WV
  • Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff. Jim Castleberry, FL
  • Excellent reply, and also very quick. Really sounds like the Expert knows what he is talking about. I will be back to use your service when I need more help with my RV. Dutch USA
 
 
 

Meet The Experts:

 
 
 
  • Chris (aka-Moose)

    Technician

    Satisfied Customers:

    846
    16 years of experience
< Last | Next >
  • http://ww2.justanswer.com/uploads/MU/muddyford/2012-6-13_1204_1.64x64.png Chris (aka-Moose)'s Avatar

    Chris (aka-Moose)

    Technician

    Satisfied Customers:

    846
    16 years of experience
  • http://ww2.justanswer.com/uploads/TE/TedG/2012-6-15_14759_avaLarge.64x64.jpg Ted G.'s Avatar

    Ted G.

    ASE Certified Technician

    Satisfied Customers:

    1596
    20 years auto repair experience, ASE Master Tech, Mechanical Failure consultant, Expert Witness
  • http://ww2.justanswer.com/uploads/joecamel90/2008-11-13_03615_head_shot.jpg George H.'s Avatar

    George H.

    ASE Certified Technician

    Satisfied Customers:

    1311
    ASE Master Tech 15+ yrs, AAS Automotive Technology, Factory trained Asian specialist
  • http://ww2.justanswer.com/uploads/AM/amedee/2013-10-24_23656_Amedee1.64x64.jpg Amedee's Avatar

    Amedee

    ASE Master Tech

    Satisfied Customers:

    2367
    ASE Master Tech advanced level specialist
  • http://ww2.justanswer.com/uploads/SU/supermechanic/2013-8-23_03546_500.64x64.jpg Jerry's Avatar

    Jerry

    Master Mechanic

    Satisfied Customers:

    1906
    ASE master, 30+ years. All makes and models. Trouble shooter, shop forman, service manager
  • http://ww2.justanswer.com/uploads/CR/crzydrvr00/2013-11-3_12123_246347.64x64.jpg Richard's Avatar

    Richard

    ASE Certified Technician

    Satisfied Customers:

    942
    12 years Ford Lincoln/Mercury Jaguar dealership as a technician and shop foreman reparing all makes
  • http://ww2.justanswer.com/uploads/ST/Steve7654/2012-6-5_215929_japic800x660.64x64.jpg Steve's Avatar

    Steve

    Auto Service Technician

    Satisfied Customers:

    1980
    25+ yrs experience as a professional working technician; ASE L1 master technician