Steve83 Posted August 12, 2019 Share Posted August 12, 2019 Not sure how to test a coil...Haynes manual & a digital multimeter. Link to comment Share on other sites More sharing options...
reamer Posted August 26, 2019 Author Share Posted August 26, 2019 Not sure how to test a coil...Haynes manual & a digital multimeter. Soooo. the carb is being delivered tomorrow, from National carb in FLA. With lifetime warranty, they state they will rebuild, flow test and dyno it. We see tomorrow if all this recent pain was the carb or I still have the issue. If all is good, I guess I have to consider the timing chain exercise "guilty by association" with all that slop in it.. Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 26, 2019 Share Posted August 26, 2019 Soooo. the carb is being delivered tomorrow, from National carb in FLA. With lifetime warranty, they state they will rebuild, flow test and dyno it. We see tomorrow if all this recent pain was the carb or I still have the issue. If all is good, I guess I have to consider the timing chain exercise "guilty by association" with all that slop in it.. Not quite sure what you are saying, Ron. Try that again? I'm kinda slow. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted August 26, 2019 Share Posted August 26, 2019 Not quite sure what you are saying, Ron. Try that again? I'm kinda slow. I think what he's saying is that he feels frustrated the timing chain did not fix the trucks engine problem. But there was a lot of insistence that it was not a fuel delivery issue. And I personally still question if it is. Too much fuel is hard to fathom unless the float valve has sunk or the powervalve failed, and usually these would cause a problem at idle that goes away at higher rpms or under load. Whereas, an ignition fault usually starts to be noticeable under load, but gets progressively worse over time. This is really the only thing I can see leaving a fuel fouled plug if the cam timing is ok. But, as we all know, it's challenging to provide diagnosis over the internet. Imagine, Gary, if you were a parts swapper and were unable to tell that Big Blues damper had slipped a few degrees. Would you understand why the engine was down on power? Or knocking? Or running hot? When everything was right, according to the book. Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 26, 2019 Share Posted August 26, 2019 I think what he's saying is that he feels frustrated the timing chain did not fix the trucks engine problem. But there was a lot of insistence that it was not a fuel delivery issue. And I personally still question if it is. Too much fuel is hard to fathom unless the float valve has sunk or the powervalve failed, and usually these would cause a problem at idle that goes away at higher rpms or under load. Whereas, an ignition fault usually starts to be noticeable under load, but gets progressively worse over time. This is really the only thing I can see leaving a fuel fouled plug if the cam timing is ok. But, as we all know, it's challenging to provide diagnosis over the internet. Imagine, Gary, if you were a parts swapper and were unable to tell that Big Blues damper had slipped a few degrees. Would you understand why the engine was down on power? Or knocking? Or running hot? When everything was right, according to the book. Yes, it is hard to diagnose over the internet. One person's terminology isn't the same as another's, and all of a sudden you have a misunderstanding. And a diagnosis based on misunderstandings is usually wrong. Anyway, we shall soon see if the carb fixes it. Link to comment Share on other sites More sharing options...
reamer Posted August 26, 2019 Author Share Posted August 26, 2019 Yes, it is hard to diagnose over the internet. One person's terminology isn't the same as another's, and all of a sudden you have a misunderstanding. And a diagnosis based on misunderstandings is usually wrong. Anyway, we shall soon see if the carb fixes it. Just going by observation. With the carb "security sealed" by the Carb company I could not even take the top off to look at the floats, so pulling the carb showed the intake soaked, and with carbonized plugs. to eliminate the carb, re-build it. Same with the timing chain, with over a inch of slop observed, since its not correct, replace the chain/gears. (needed it anyway) So if it still runs like crap, off to the next issue. Timing chain,... Check! Carb rebuilt,... Check! Fuel pressure @ 7 psi WOT for 30 seconds, But no load,.. Check! Dizzy complete rebuild 3 seasons ago,... Check! Next? Electrical? we will see this after noon... Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 26, 2019 Share Posted August 26, 2019 Just going by observation. With the carb "security sealed" by the Carb company I could not even take the top off to look at the floats, so pulling the carb showed the intake soaked, and with carbonized plugs. to eliminate the carb, re-build it. Same with the timing chain, with over a inch of slop observed, since its not correct, replace the chain/gears. (needed it anyway) So if it still runs like crap, off to the next issue. Timing chain,... Check! Carb rebuilt,... Check! Fuel pressure @ 7 psi WOT for 30 seconds, But no load,.. Check! Dizzy complete rebuild 3 seasons ago,... Check! Next? Electrical? we will see this after noon... Makes sense .... Check! But I'd still dial the fuel pressure down to 5 or less. From what I've read anything over 6 can be a problem, although usually at idle rather than elsewhere. Link to comment Share on other sites More sharing options...
reamer Posted August 26, 2019 Author Share Posted August 26, 2019 Makes sense .... Check! But I'd still dial the fuel pressure down to 5 or less. From what I've read anything over 6 can be a problem, although usually at idle rather than elsewhere. If it were leaning towards electrical, like a coil issue, wouldn't the factory tac jump around? It has always been smooth.. And I always have 2 mounted Duraspark modules, mounted under the hood, 1 pops, instantly plug in the emergency reserve, It ran the same on either box... The strange issue on fuel pressure is sometimes I observe the pressure on the dial at, say 6 psi, and run the truck for a bit, and it would accelerate fine, plenty of power, yet the pressure gauge would read zero, ( but run fine as mentioned) Wats up with that? This afternoon will be interesting...... Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 26, 2019 Share Posted August 26, 2019 The strange issue on fuel pressure is sometimes I observe the pressure on the dial at, say 6 psi, and run the truck for a bit, and it would accelerate fine, plenty of power, yet the pressure gauge would read zero, ( but run fine as mentioned). I'm lost. You observe the pressure on the dial at 6 but the pressure is zero? Are you saying at some times it is at 6 and runs fine and other times it is at 0 and runs fine? On the ignition, the tach is driven by the signal in the primary circuit of the coil. But if the secondary circuit goes bad then the plugs won't fire correctly but the tach will read smoothly. And I've seen coils that fail in the secondary when they get warm. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted August 26, 2019 Share Posted August 26, 2019 If it were leaning towards electrical, like a coil issue, wouldn't the factory tac jump around? It has always been smooth.. And I always have 2 mounted Duraspark modules, mounted under the hood, 1 pops, instantly plug in the emergency reserve, It ran the same on either box... The strange issue on fuel pressure is sometimes I observe the pressure on the dial at, say 6 psi, and run the truck for a bit, and it would accelerate fine, plenty of power, yet the pressure gauge would read zero, ( but run fine as mentioned) Wats up with that? This afternoon will be interesting...... You have 2 modules, but do you have two coils? 0 fuel pressure is not going to cause flooding, in any case. Link to comment Share on other sites More sharing options...
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