ratdude747 Posted November 18, 2019 Author Share Posted November 18, 2019 If the outside of the plug was wet it may be that the spark was jumping down the plug to ground. That would certainly give you a miss, but that usually happens under load. Anyway, perhaps new plugs would make a big difference. Clearer picture of plugs: Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted November 18, 2019 Share Posted November 18, 2019 Clearer picture of plugs: Definitely burning some oil at the front of that block! Link to comment Share on other sites More sharing options...
ratdude747 Posted November 18, 2019 Author Share Posted November 18, 2019 Definitely burning some oil at the front of that block! Note- these pics were taken before I re-installed the plugs following the wet/dry compression test. I'll order new plugs and when I return from Canada I'll install them... me thinks plug #1 fouled the rest of the way due to the wet test oil. Seemed to run OK for a short bit, then started missing and occassionally popping . Not like it was running before. Link to comment Share on other sites More sharing options...
Gary Lewis Posted November 18, 2019 Share Posted November 18, 2019 Note- these pics were taken before I re-installed the plugs following the wet/dry compression test. I'll order new plugs and when I return from Canada I'll install them... me thinks plug #1 fouled the rest of the way due to the wet test oil. Seemed to run OK for a short bit, then started missing and occassionally popping . Not like it was running before. Yep, #1 is a problem. Something is wrong with that cylinder, and most likely the rings. Link to comment Share on other sites More sharing options...
ratdude747 Posted November 29, 2019 Author Share Posted November 29, 2019 Yep, #1 is a problem. Something is wrong with that cylinder, and most likely the rings. Got back from Canada, and replaced the #1 and #2 spark plugs (#1 was badly oil fouled). Good news: it idles better Bad news: It still shakes like mad when torqued and my highway fuel milage (so far) is just over 10 MPG. It's possible that I got a short fill when I left town; I'll get a better idea when I fill up next. Still. 163 miles down (mapping my path shows it closer to 170 miles, close enough) and 15.3 gallons in is depressing. Tired engine? Looks like I have a rebuild/replace coming up... Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted November 29, 2019 Share Posted November 29, 2019 Got back from Canada, and replaced the #1 and #2 spark plugs (#1 was badly oil fouled). Good news: it idles better Bad news: It still shakes like mad when torqued and my highway fuel milage (so far) is just over 10 MPG. It's possible that I got a short fill when I left town; I'll get a better idea when I fill up next. Still. 163 miles down (mapping my path shows it closer to 170 miles, close enough) and 15.3 gallons in is depressing. Tired engine? Looks like I have a rebuild/replace coming up... It may be depressing for an I-6, but that's every day of the last 32 years for me! 🤣 Link to comment Share on other sites More sharing options...
Gary Lewis Posted November 29, 2019 Share Posted November 29, 2019 Got back from Canada, and replaced the #1 and #2 spark plugs (#1 was badly oil fouled). Good news: it idles better Bad news: It still shakes like mad when torqued and my highway fuel milage (so far) is just over 10 MPG. It's possible that I got a short fill when I left town; I'll get a better idea when I fill up next. Still. 163 miles down (mapping my path shows it closer to 170 miles, close enough) and 15.3 gallons in is depressing. Tired engine? Looks like I have a rebuild/replace coming up... With the 300 six and an AOD you should be knocking on the door of 20 MPG. David is with his, and while his has the manual tranny with OD, the AOD should come close. So you may well have a worn engine. But I'd still run a leak-down test to make sure before you decide to rebuild it. And speaking of rebuilding it, someone on here has to try Scotty The Mad Porter's 300 build. He's one of the premier gurus on the 460, but he says he does a mean 300 as well. Link to comment Share on other sites More sharing options...
85lebaront2 Posted November 30, 2019 Share Posted November 30, 2019 Got back from Canada, and replaced the #1 and #2 spark plugs (#1 was badly oil fouled). Good news: it idles better Bad news: It still shakes like mad when torqued and my highway fuel milage (so far) is just over 10 MPG. It's possible that I got a short fill when I left town; I'll get a better idea when I fill up next. Still. 163 miles down (mapping my path shows it closer to 170 miles, close enough) and 15.3 gallons in is depressing. Tired engine? Looks like I have a rebuild/replace coming up... Ok, several items, one have you checked the timing, SPOUT connector unplugged with a warm engine. After doing that and reconnecting the SPOUT see if you are getting spark advance. These trucks do not have an MIL so there is nothing to warn you if it isn't working right. One other very common problem with many in-line 6 engines, balancer coming apart. Some had a reference mark from the hub to the outer ring. To find out for certain, take one of the bad plugs, gut it and thread the shell for a stop screw. Carefully install it in either #1 or #6 plug hole whichever is easier and rotate the engine by hand (socket and breaker bar) until it stops. Mark the location of the pointer on the balancer, then turn back the other way until it stops, mark the balancer again. Halfway between the marks should be TDC on the balancer, if it isn't then it needs replacing. Link to comment Share on other sites More sharing options...
ratdude747 Posted December 1, 2019 Author Share Posted December 1, 2019 Ok, several items, one have you checked the timing, SPOUT connector unplugged with a warm engine. After doing that and reconnecting the SPOUT see if you are getting spark advance. These trucks do not have an MIL so there is nothing to warn you if it isn't working right. One other very common problem with many in-line 6 engines, balancer coming apart. Some had a reference mark from the hub to the outer ring. To find out for certain, take one of the bad plugs, gut it and thread the shell for a stop screw. Carefully install it in either #1 or #6 plug hole whichever is easier and rotate the engine by hand (socket and breaker bar) until it stops. Mark the location of the pointer on the balancer, then turn back the other way until it stops, mark the balancer again. Halfway between the marks should be TDC on the balancer, if it isn't then it needs replacing. 1. Have checked previously, not the issue. SPOUT disconnected, at 10 BTDC, the idle is completely different, so if I lost advance, it would be obvious. It idles fine, the issue is when I try to get torque out of it. 2. Also checked previously, my indicator is spot on (within a degree, seems to be bang on). Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted December 1, 2019 Share Posted December 1, 2019 1. Have checked previously, not the issue. SPOUT disconnected, at 10 BTDC, the idle is completely different, so if I lost advance, it would be obvious. It idles fine, the issue is when I try to get torque out of it. 2. Also checked previously, my indicator is spot on (within a degree, seems to be bang on). If the "idle is completely different" with the spout out (locked timing) maybe your ecu is the problem? Or one of the sensors the ecu uses to determine timing? Temp, vacuum, throttle position, etc... Of course it would be, just like connecting vacuum to DSII. But if it is hunting around, makes me think the computer's being tricked. Link to comment Share on other sites More sharing options...
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