RED-Z06 2,221 #1 Posted January 21, 2022 Its been on like 10 working hours and its showing some flaws...i was warming it up tonight and hit the shop lights..lol 1 2 Share this post Link to post Share on other sites
WHX?? 48,828 #2 Posted January 21, 2022 Yah my pepper pots do that too... might be running abit lean. Try tweaking the main out a quarter to 3/4 turn till she runs rough then go in just a hair. 1 Share this post Link to post Share on other sites
Achto 27,601 #3 Posted January 21, 2022 That ain't no Natural gas engine!!! You should not glow like that unless you are under full load. Give that ole girl some more fuel !!! 2 Share this post Link to post Share on other sites
RED-Z06 2,221 #4 Posted January 21, 2022 Plug comes out dark cocoa brown, she had 217⁰ cylinder head temps...shes tuned well. Only hits 245⁰ under a 25% load. Share this post Link to post Share on other sites
Jeff-C175 7,202 #5 Posted January 21, 2022 (edited) 19 minutes ago, RED-Z06 said: Plug comes out dark cocoa brown, she had 217⁰ cylinder head temps...shes tuned well. Only hits 245⁰ under a 25% load. So what are you saying? That you think that it's normal? Edited January 21, 2022 by Jeff-C175 1 1 Share this post Link to post Share on other sites
Snoopy11 5,714 #6 Posted January 21, 2022 (edited) That is not normal. Don Edited January 21, 2022 by Snoopy11 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #7 Posted January 21, 2022 11 minutes ago, Jeff-C175 said: So what are you saying? That you think that it's normal? At night...thin walled muffler glowing at the port of a running engine, its not abnormal...most people dont run engines in pitch black conditions, most people dont run saws at night either...but the mufflers will take on a nice glow if you ever get a chance to really run one like that. Going by the plug, cht, the fact it's not bogging at all...yes, its normal. My phone in night mode also makes it seem much brighter than it is...to the naked eye there was only a small patch of orange where the port dumps in. 1 Share this post Link to post Share on other sites
Jeff-C175 7,202 #8 Posted January 21, 2022 9 minutes ago, RED-Z06 said: At night...thin walled muffler glowing at the port of a running engine, its not abnormal...most people dont run engines in pitch black conditions, most people dont run saws at night either...but the mufflers will take on a nice glow if you ever get a chance to really run one like that. Going by the plug, cht, the fact it's not bogging at all...yes, its normal. My phone in night mode also makes it seem much brighter than it is...to the naked eye there was only a small patch of orange where the port dumps in. So you ARE saying that you believe it's normal then? Why do ya reckon it's backfiring? 1 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #9 Posted January 21, 2022 11 minutes ago, Jeff-C175 said: So you ARE saying that you believe it's normal then? Why do ya reckon it's backfiring? Because thats generally what gas does when it hits metal heated over its flash point. This is why engines made in the past 20+ years use a solenoid to shut off fuel flow at the Jet on shut down. After mowing yesterday at full throttle for 45 minutes i shut it down..and about 10 seconds after the engine stopped it let out the daintiest little "pop". 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #10 Posted January 21, 2022 Went out and pulled the plug...havent touched it since i made that video...you tell me... 1 Share this post Link to post Share on other sites
Jeff-C175 7,202 #11 Posted January 21, 2022 1 hour ago, RED-Z06 said: you tell me Too rich. 1 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #12 Posted January 21, 2022 22 minutes ago, Jeff-C175 said: Too rich. But @WHX?? and @Achto said to give it more fuel...??? The ground strap was just starting to clean up the soot from the choke from starting cold...with a load it cleans right up to dark cocoa. Its running very well, temps dropped from 65 to 35 in a couple hours with a chance of snow tonight. 1 Share this post Link to post Share on other sites
Jeff-C175 7,202 #13 Posted January 21, 2022 (edited) 6 minutes ago, RED-Z06 said: But @WHX?? and @Achto said to give it more fuel...??? Yeah, I saw they said that... but that plug is telling me it's too rich. But, what do I know? Lean it out and see what happens... How would a ground strap clean up soot? Edited January 21, 2022 by Jeff-C175 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #14 Posted January 21, 2022 8 minutes ago, Jeff-C175 said: Yeah, I saw they said that... but that plug is telling me it's too rich. But, what do I know? Its a bit rich, i normally do a plug read after at least a minute under a good load on a 4 stroke, last plug read it was dark cocoa, after 45 minutes mowing. Kohlers get super sluggish when they are lean, you can always tell, they take forever to warm up before they'll take gas, and you'll get backfires on decel. Some years ago i was pulling a Farmall C with my 702...the K181S was at full governor, 2nd gear...frame was torqued up. Had a stack on it, out into a 90 elbow up 10" to a briggs muffler then 12" up to a flap. Id used that thing a year and it had burned the paint off the exhaust up to about 2" below the muffler. After about a minute of 100% power it burned the paint up past the muffler...ol girl got really stupid hot. After shut down it dieseled for a good 15 seconds. Later that year i tore it down to fix a leaking sump gasket and pulled the piston out...she was good, no crown erosion at all, no cracked rings or lands, valves not burnt. They are incredibly tough engines, ive seen them come in run with no air filter until they no longer ran on ether...and they rebuild fine somehow. 1 Share this post Link to post Share on other sites
Maxwell-8 4,277 #15 Posted January 21, 2022 (edited) 3 hours ago, RED-Z06 said: when they are lean, you can always tell, they take forever to warm up When lean, temperatures go trough the roof very fast. explaining the exhaust glowing. The last engine I ran lean looks like this currently: Edited January 21, 2022 by Maxwell-8 2 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #16 Posted January 21, 2022 4 hours ago, Maxwell-8 said: When lean, temperatures go trough the roof very fast. explaining the exhaust glowing. The last engine I ran lean looks like this currently: Looks like a chrome piston out of a kool bore briggs possibly. Im seeing a lubrication issue at the big end, the high break suggests potentially an oversoeed issue. A lean 4 stroke will detonate and eventually seize the top end...but im not seeing a seized piston there. 1 Share this post Link to post Share on other sites
peter lena 8,634 #17 Posted January 21, 2022 @RED - Z06 , that heat glow is the first stage of the internal baffling of that muffler , combinations of fuel mixture , and metal break down add up . made a stainless muffler many years ago , after finding an original muffler schematic of that , all my pieces were , 316 grade stainless , fully tig welded . don't ask me for the print , that was over 30 years ago . that plug color , is obviousely rich , check out related wiring , in addition to carb improvements . have a fuel filter close to carb? typically use problem to track down the source .anything wiring related , and fuel , should be checked out , only if you want to , pete 1 1 Share this post Link to post Share on other sites
Snoopy11 5,714 #18 Posted January 21, 2022 5 hours ago, RED-Z06 said: Looks like a chrome piston out of a kool bore briggs possibly. Im seeing a lubrication issue at the big end, the high break suggests potentially an oversoeed issue. A lean 4 stroke will detonate and eventually seize the top end...but im not seeing a seized piston there. NoNoNoNoNo... @Maxwell-8 and @Jeff-C175 are both correct. Although... I am not there... and can't see what has been done to the engine... here is my analysis of this issue: It would appear, in my opinion that the glowing could also be caused by mal-adjusted valves, leaky, and/or burnt valves. It is possible that you are pouring in more fuel... enabling it to run at what you consider to be normal... but it is not at the correct mixture/ratio... which could be causing SOME of the issues we see here. I am wondering... if possibly... since you say that you measured everything on the bottom-end and put everything together properly... and more information is now coming along... you need to disassemble the top end and check. Ignition timing... which I have already mentioned several times to check (but have gotten ignored)... is another possible suspect. @squonk... I hate to throw you into the fire... literally... but what is your opinion? Don 2 Share this post Link to post Share on other sites
Snoopy11 5,714 #19 Posted January 21, 2022 13 hours ago, Jeff-C175 said: How would a ground strap clean up soot? I would love to hear that explanation... 13 hours ago, RED-Z06 said: burned the paint off the exhaust I am struggling to understand the relevancy of this to the conversation? I have run many exhaust systems... different types of mufflers... etc... and every time... the stupid/el-cheapo paint burns and flakes off. What are you telling me? 5 hours ago, RED-Z06 said: Im seeing a lubrication issue at the big end I see heat marks on the rod bearing. AND FYI... rods break in multiple places when they break... they break at the top because after coming apart, they hit the sidewall of the engine, and break right up at the wrist-pin. THUS, why you see part of the piston skirt is broken. Also, if you notice, the rod cap split down the middle... between the bolts... that is common of a rod super-heating. What @peter lena is saying is that... you need to be proactive. That is all I have been saying since this engine project began. Don 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #20 Posted January 21, 2022 11 minutes ago, Snoopy11 said: NoNoNoNoNo... @Maxwell-8 and @Jeff-C175 are both correct. Although... I am not there... and can't see what has been done to the engine... here is my analysis of this issue: It would appear, in my opinion that the glowing could also be caused by mal-adjusted valves, leaky, and/or burnt valves. It is possible that you are pouring in more fuel... enabling it to run at what you consider to be normal... but it is not at the correct mixture/ratio... which could be causing SOME of the issues we see here. I am wondering... if possibly... since you say that you measured everything on the bottom-end and put everything together properly... and more information is now coming along... you need to disassemble the top end and check. Ignition timing... which I have already mentioned several times to check (but have gotten ignored)... is another possible suspect. @squonk... I hate to throw you into the fire... literally... but what is your opinion? Don Different engine...this is the K241S on my C100, 2nd owner, its never been apart, it got blocked in a cinderblock garage at least 16 years ago by a 65 Mustang...we dont actually know how long before that, but they stopped tagging the car 16 years ago, but it had likely been there quite a bit longer based upon the stuff that was around it that had to go in there before the car (size and weight). This engine never disappoints, never gives any problems..no odd noises, no smoke, starts easy below freezing and welcomes a couple acres of mowing. The knocking engine is a 312-8 i was given that had sat outside almost 2 decades uncovered, partly disassembled, engine seized, tires rotted off, wheels missing chunks of bead due to rust, it was going to scrap but I took it in. The engine ran but had limited governor control due to a slung weight. I took it apart to replace the gear...deglazed the bore, did my normal cleanup in a hot soapy tank...but quickly developed a noise, i took it back apart and found soft metal wear (no ferrous metal in the oil) and replaced all the worn parts, and it still sounds the same... 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #21 Posted January 21, 2022 13 hours ago, Jeff-C175 said: Yeah, I saw they said that... but that plug is telling me it's too rich. But, what do I know? Lean it out and see what happens... How would a ground strap clean up soot? Cold start...choke, soot gets deposited on the plug, valves...the choke is progressively turned off...as the individual components come up to temperature they will burn off the soot. Ground strap being projected, it will clean up first...then the ceramic side...Upon the plug reaching full temperature it should be about as clean as its going to get, this engine did not get up to full temperature after cold starting. But ill go do that right now... 1 Share this post Link to post Share on other sites
Snoopy11 5,714 #22 Posted January 21, 2022 2 minutes ago, RED-Z06 said: Different engine...this is the K241S The knocking engine is a 312-8 Oh... wow... so... you have 2 engines that... are running like crap...? I swear it sounds like that engine is knocking in the video in this thread... I guess I could be mistaken... Diagnostic-wise... that changes nothing... that I said. Look, I wish that I could help more... but I think I need to recuse myself from this conversation. I can't be of help... obviously... as everything I say... is merely pissing in the wind... Y'all be good now... Don 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #23 Posted January 21, 2022 Put the plug back in...got it up to temp and ran it with the deck on about 3 minutes for a little load, its 31⁰ so cht was low at 224⁰ due to low ambient temp...but it stabilized there. 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #24 Posted January 21, 2022 24 minutes ago, Snoopy11 said: Oh... wow... so... you have 2 engines that... are running like crap...? I swear it sounds like that engine is knocking in the video in this thread... I guess I could be mistaken... Diagnostic-wise... that changes nothing... that I said. Look, I wish that I could help more... but I think I need to recuse myself from this conversation. I can't be of help... obviously... as everything I say... is merely pissing in the wind... Y'all be good now... Don The C100 runs great, this wasnt a complaint...just, you dont realize what muffler paint goes through until you really see the hot spots on the muffler...im extremely happy with this K241. Even the M12...runs well, just knocks. 2 Share this post Link to post Share on other sites
RED-Z06 2,221 #25 Posted January 21, 2022 Ill bet...if anyone of you went out to your K241 or K301 with this style muffler at night and run it in...kill all the lights, your mufflers glow the same. 2 Share this post Link to post Share on other sites