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 Mechanic Martyn Your Own Question

Mechanic Martyn
Mechanic Martyn, Australia Car Mechanic
Category: Australia Car
Satisfied Customers: 987
Experience:  Advanced trade certificate in Automotive engineering
17982882
Type Your Australia Car Question Here...
Mechanic Martyn is online now
A new question is answered every 9 seconds

Ford f100 79 model 2wd: I have a 79 model f100 351 clev on

Resolved Question:

I have a 79 model f100 351 clev on duel fuel adjusted timing on petrol but it still pings its head off yet on gas no noise and usable power do not have to back off, it's got c6 auto. Thanks mat
Submitted: 1 year ago.
Category: Australia Car
Expert:  Mechanic Martyn replied 1 year ago.
Hello
What do you have it set on now - how many degrees of advance?
regards
Mechanic Martyn
Customer: replied 1 year ago.

It doesn't seem to matter where its set at as it always pings on petrol but is ok on gas. I can accelerate on gas but on petrol I have to back off on the pedal as it pings too much. Ive adjusted the dizzy in many positions.

Expert:  Mechanic Martyn replied 1 year ago.
Okay - yes I get that but have you been using a timing light to get a reference or have you just been doing it by ear.
LPG will do about 20 degrees or so more advance than petrol without a problem.
The trouble is if you set up for LPG the petrol will pink and if you set up for petrol the lpg will lack power.
There is an electronic box from MSD that does a change over in timing. It's worth the investment.
I have a 84 f100 with a 351c and a electronic distributor in it. I find I set the initial timing to about 6 degrees on petrol. I have an lpg kit for it but I haven't fitted it up yet.
What grade petrol are you using?
I find using an octane booster can help too but it can get expensive.
regards
Mechanic Martyn
Mechanic Martyn, Australia Car Mechanic
Category: Australia Car
Satisfied Customers: 987
Experience: Advanced trade certificate in Automotive engineering
Mechanic Martyn and other Australia Car Specialists are ready to help you

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
  • Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
 
 
 

Meet The Experts:

 
 
 
  • Curtis

    Australia Car Mechanic

    Satisfied Customers:

    1605
    Qualified Automotive Mechanic, LPG & Airconditioning Diagnostic Technician.
< Last | Next >
  • http://ww2.justanswer.com/uploads/TechCurtis/2010-10-21_204813_jaavatar.png Curtis's Avatar

    Curtis

    Australia Car Mechanic

    Satisfied Customers:

    1605
    Qualified Automotive Mechanic, LPG & Airconditioning Diagnostic Technician.
  • http://ww2.justanswer.com/uploads/GL/GlennBradley/2012-9-1_102754_DSCF3324c.64x64.jpg Glenn Bradley's Avatar

    Glenn Bradley

    Australian Car Mechanic

    Satisfied Customers:

    664
    Ex Transmission Shop Owner, Driveline Specialist, 30+ years in the Australian Automotive Industry
  • http://ww2.justanswer.com/uploads/BR/Brogs70/2011-5-4_13942_weddingpicsfromMelandVicki004.64x64.jpg Scott B's Avatar

    Scott B

    Australia Car Mechanic

    Satisfied Customers:

    478
    Qualified Automotive Mechanic, Service Manager & Proprietor 20+ years
  • http://ww2.justanswer.com/uploads/Technopro/2010-04-14_162248_Arm_JA.jpg Technopro's Avatar

    Technopro

    Australia Car Mechanic

    Satisfied Customers:

    129
    15+ years of experience in Automotive Repair Techniques and Diagnosis Expert.
  • http://ww2.justanswer.com/uploads/MA/MarkBarnes1967/2011-8-13_93816_MarkakaTOMUCH.64x64.JPG Mark's Avatar

    Mark

    Mechanic

    Satisfied Customers:

    571
    26 Years as a Vehicle Mechanic in Australian Military
  • http://ww2.justanswer.com/uploads/35/350matt/2012-6-7_182356_matsavatr.64x64.jpg Matt's Avatar

    Matt

    Engineer

    Satisfied Customers:

    437
    Automotive Engineer for 20 years, BEng hons degree,
  • http://ww2.justanswer.com/uploads/gemmechanic/2009-05-04_110543_dsc07268.jpg Mechanic Martyn's Avatar

    Mechanic Martyn

    Australia Car Mechanic

    Satisfied Customers:

    303
    Advanced trade certificate in Automotive engineering