Idle Settings/Glow Plug/Head Button - DIAL-UP BEWARE

[YeahYeah]

Idle Settings / Glow Plug / Head Button - DIAL-UP BEWARE

Ok, so the other day I was having some trouble getting my truck up and running properly, as detailed here: Won't Start/Run/Etc.

Well, today I changed the fuel lines, checked the fuel filter, cleaned the air filter, adjusted the 2-speed, and swapped in a new glow plug. However, I also got some pictures of the carb in different positions, as well as pictures of the glow plug and the head button. I was hoping you guys could take a look and let me know if it sheds any more light on the problems I was seeing the other day. Thank you very much in advance.

I know you can sometimes tell if it is running too rich or too lean by reading the glow plug and head button - but I don't have the experience.

I also noticed today that I could not turn the engine over with the glow plug in tight. If I loosed it a touch, I could turn it over relatively easily by hand. Is this just a sign of a good seal or is it something else? The engine has about 1 gallon through it.

Also, HOORAY for the MACRO setting on digital cameras!

Carb at idle - 1

Carb at idle - 2

Carb at idle - 3

Carb at Wide Open Throttle 1

Glow Plug - 1

Glow Plug - 2

Glow Plug - 3

Head Button - 1

Head Button - 2

Head Button - 3

 

[Double-O-Zilch]

Looks to me like your glow plug element is tweaked and you're running rich. My thread may help you.

How to read a glow plug

 

[Jeremy]

Too me it looks lean !!!!!

 

[Double-O-Zilch]

I was not paying attention, trying to get video up. Sorry. Is does look like some pitting is going on there. What % of fuel do you run and how many head shims? Also what is your normal running temp?

 

[YeahYeah]

I used Trinity Monster Horsepower 20% for the first 85% or so of a gallon, then bought some Trinity Platinum 20% after I left the old fuel in my trunk too long.

It's running 4 head shims, if memory serves, and I have NEVER seen a temperature over 250. In fact, the last time I drove it, I didn't see a temperature over 145, though, I never did manage to keep it running too long.

I have not leaned it out more than maybe 3/4 turn from flush, and I doubt it's even been leaned that far.

Thanks for the help guys.

 

[Double-O-Zilch]

Where is your LSN sitting at and what glow plug are you running? It does look like the oil in the fuel was flash burning into the little globules on the glow plug. You may have an air leak and didn't catch it till now. If you run at those temps and those settings, it's the only thing I can think of. And I'm pretty sure I see pitting but in your case running the lower nitro %, you should be able to remove a shim and not get pitting. Maybe I'm in over my head here! LOL.

 

[MotoPsycho]

Let's back up just a schosh... With the looks of the carb and surrounding area, it seems obvious the air filter was caked with "gook" and the engine was running rich.

With your added description this sounds like a correct diagnosis (running rich).

1) The lower temps is are sure sign of a rich condition
2) When VERY rich at idle, engine will bog or die with quick "blips" but you may be able to ramp it up slowly, to get to higher RPM
3) Leaning an engine out that seems rich at idle, when it has very little air flow will cause it to die. The air/fuel mixture is at it's bare minimum -fuel is cut as low as possible to work with minimal available air - reducing fuel any more doesn't leave enough air/fuel mix for the engine to run.
4) If you run across a hard starting condition while cranking over, try pinching the fuel line off (hold it pinched), while continuing to crank. If after 5-10 seconds, it starts to fire - or fires and runs for a few seconds, then dies - it is too rich.

Once you master that, you can pinch it until it fires, or fires and runs, and pinch and "unpinch" to keep it running until you can make needed tuning changes. (leaning it out)


And remember, Parker's sig line used to read something like: " It's pure weapons grade bolognium"

 

[YeahYeah]

Thank you very much for the input so far guys. I won't get a chance to try to fire it back up 'til this weekend probably, but I'll be sure to try to put it all into practice!

As for my LSN, it is set to factory settings - I haven't touched the LSN settings at all. My glow plug is an O'Donnell #100 Glow Plug Medium.

I may have an air leak, I haven't sealed the engine or anything, but it would seem to be a new development because it ran fine before. If I am getting pitting because of detonation, shouldn't I ADD a shim, rather than remove? (Or did you mean that I should be able to remove a shim and still be OK?).

As for the air filter being caked with 'gook', there really wasn't anything stuck on the air filter at all. I know that looking at how dirty everything is, that is hard to believe, but there wasn't any grass or dirt or mud or anything caked on the filter. It could still have needed cleaning - but I don't think it was so bad that it could cause these problems. Of course, I'm just guessing, and I cleaned my filters out yesterday, so we'll see.

As I said, I can only imagine it was too rich - the temperatures were VERY low, the engine seemed to be very difficult to start and would bog down at low RPM, and when I took the glow plug out to check, it was very wet. Plus, I haven't leaned it out hardly at all, and I know they come set very rich from the factory. But, I don't want to just crank it way leaner because I don't want to destroy the thing either. I have re-set the carb to flush, and I will go from there next chance I get. I've also put in a new glow plug (another O'Donnell #100), as that one seems to be pretty fried.

Thanks again for the help guys, by all means please keep it coming!