[NSRCA-discussion] Mintor 1.70 Question

[Pascoe,Tim [Burlington]]

Gray,

 

            I do have the pump mod specified by Lance. I did that before running the engine. I'm definitely worried about the damage due to backfire :-( I also have the upgraded con rod. As for being sure the pump is functioning, can you give me a good test for this? I could easily be convinced that it is somehow not putting out the pressure it should, given where I am on the adjustments. As I said in another post, the pump was disassembled and checked by Mike Darr from Michigan, who has run the engine quite a bit, and who helped me track down the original carb issue. We didn't see any problems then, and the engine has very little time on it since then.

 

Thanks for the suggestions.

Tim Pascoe

  _____  

From: nsrca-discussion-bounces at lists.nsrca.org [mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of Gray E Fowler
Sent: August 3, 2006 10:39 AM
To: NSRCA Mailing List
Subject: Re: [NSRCA-discussion] Mintor 1.70 Question

 


Tim 

Are you sure that the pump is functioning? The backfire is a sign of lean mid and will damage the CF pipe baffles. During the hot summer, the pump can get very hot. Do you have the pump insulator modification on your engine? Mintor designed this at Lance's request, as the Texans discovered this problem flying in 100F+ temps that exceed European climates. 



Gray Fowler
Senior Principal Chemical Engineer
Radome and Composites Engineering
Raytheon 



"Pascoe,Tim [Burlington]" <Tim.Pascoe at ec.gc.ca> 
Sent by: nsrca-discussion-bounces at lists.nsrca.org 

08/03/2006 09:01 AM 

Please respond to
NSRCA Mailing List <nsrca-discussion at lists.nsrca.org>

To

<nsrca-discussion at lists.nsrca.org> 

cc

 

Subject

[NSRCA-discussion] Mintor 1.70 Question

 

 

 




Hey List, 

        I've been setting up a Mintor 1.70 in a new plane, and am running into some minor difficulties. I first started running the engine last fall, and has some mechanical trouble which lead to some major needle twisting. After getting the mechanical trouble out of the way, I've found myself trying to get the pump/needles back to where they should be, with varying levels of success. 

        The original symptoms seemed to indicate a lean mid-range on the engine; dying on throttle up after a down line, the odd backfire when spooling up from idle in the flat. I've been constantly richening the pump in an attempt to solve these issues, and it seemed to work at first. Better mid-range, no dead sticks. However, I am still getting the odd backfire, and I'm really afraid that I'm going to start busting stuff. I am now well in on the pump screw, much further than another Mintor 1.70 flier running the same fuel, and a long way past flush with the screw housing. The mid-range needle is also on the rich side of the setting. 

        Any suggestions would be appreciated. The lines have all been checked, and they are fine (pretty much new anyway). The tank clunk is free, and the vent line is clear. Is it possible the backfire issue is in fact a too rich mixture, and I'm chasing the problem the wrong way? 

        It's getting frustrating, as the engine is great in many other ways - very easy to start, phenomenal power, good throttle response. I'm running a 17x13 prop (soon to switch to the new 18.1x10) on an Aeroslave carbon pipe set approx ¼ to ½ inch longer than the Aeroslave recommended length, with Cool Power 15% for fuel. 

Tim Pascoe_______________________________________________
NSRCA-discussion mailing list
NSRCA-discussion at lists.nsrca.org
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.nsrca.org/pipermail/nsrca-discussion/attachments/20060803/337eef04/attachment-0001.html