| Slant Six Forum https://www.slantsix.org/forum/ |
|
| 225 Slant Six Industrial Knock https://www.slantsix.org/forum/viewtopic.php?t=68099 |
Page 1 of 1 |
| Author: | tspang80 [ Wed Feb 26, 2025 4:59 am ] |
| Post subject: | 225 Slant Six Industrial Knock |
I am hoping someone can help me with were to start chasing down the knock I have. Going to try to upload the video here or put a link to it on YouTube. I appreciate any advice received. The motor is in an aircraft tug and is a 1990 225 Chrysler 225 Industrial. Thanks again. https://youtu.be/fc-ZfGX-fv8 |
|
| Author: | Greg Ondayko [ Wed Feb 26, 2025 7:09 am ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
Have you checked the Inital and total Timing with a timing light? That would be a good place to start your investigation. Is it knocking all the time? (even with no load) or is it detonation knocking aka pinging? Greg |
|
| Author: | Daddiojoe [ Wed Feb 26, 2025 8:27 am ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
Investing in a Harbor Freight automotive stethoscope is worthwhile. You can use it to pinpoint areas of knocking. Check all the peripheral stuff, like brackets, etc. to make sure they are tight and not bumping into anything. Another simple fix is looking into the flywheel bolts being loose or hitting something. |
|
| Author: | SlantSixDan [ Wed Feb 26, 2025 11:38 am ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
Quote:
Have you checked the Inital and total Timing with a timing light? Dude doesn't have spark knock, he's got engine knock. Mechanical noise, not ignition ping. If he's lucky it'll be something like the dipstick hitting the crankshaft or loose flywheel/flexplate bolts, but it sounds ominous in that "probably hafta pull and dismantle the engine" kind of way.
|
|
| Author: | mcnoople [ Wed Feb 26, 2025 1:48 pm ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
Quote:
Investing in a Harbor Freight automotive stethoscope is worthwhile. You can use it to pinpoint areas of knocking.
Harbor freight sells a two piece unit with a break in the middle of the shaft. I have had very poor luck with those units in the past. I would strongly suggest finding a slightly more expensive unit with a one piece shaft.Check all the peripheral stuff, like brackets, etc. to make sure they are tight and not bumping into anything. Another simple fix is looking into the flywheel bolts being loose or hitting something. For years I used an old car antenna mast bolted to the lid from a round one gallon washer fluid bottle. Cut the bottom off of the washer fluid bottle and use it as a megaphone. If you try this remember to hold the bottle by the cap not the antenna mast or the body of the bottle. |
|
| Author: | Greg Ondayko [ Wed Feb 26, 2025 4:15 pm ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
Quote:
Dude doesn't have spark knock, he's got engine knock. Mechanical noise, not ignition ping.
Yes I can tell that now.. was unable to watch/ listen earlier. |
|
| Author: | Rick Covalt [ Wed Feb 26, 2025 5:37 pm ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
Pull the valve cover and check all the valve settings. Sounds a little too "tinny" on my computer to be a rod or main. Maybe I have bad speakers too. Maybe an adjuster backed out. Seen a rocker shaft broken it two one time also. That will allow the valves to do some very special things! 
|
|
| Author: | SlantSixDan [ Wed Feb 26, 2025 10:04 pm ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
But it sounds as though it's hitting well and evenly on all six. Strikes me a valve(train) issue big enough to sound like that, and the affected cylinder(s) would fire poorly or not at all; the engine would run roughly. Also don't think exhaust leak is very high on this list. This is much too clanky; underhood exhaust leaks are more spit-y (small) whipcrack (large) unmuffled radial airplane engine (near central collector/headpipe). |
|
| Author: | slantzilla [ Thu Feb 27, 2025 8:01 am ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
Loose converter bolt? |
|
| Author: | tspang80 [ Thu Feb 27, 2025 8:48 am ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
Thank you all for the suggestions! I plan to tear into this weekend and you definitely gave me places to start. I will post any results. It is a really cool motor to tinker with. |
|
| Author: | Greg Ondayko [ Thu Feb 27, 2025 9:05 am ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
Quote:
Loose converter bolt?
Yes I have had loose converter bolts that have knocked like a blown engine in the past.Greg |
|
| Author: | Dart270 [ Thu Feb 27, 2025 11:26 am ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
Could be loose crank to flexplate (or flywheel) OR loose flexplate to converter bolts. Both sound a fair bit like a rod knock. MUCH easier to fix! Lou |
|
| Author: | Reed [ Thu Feb 27, 2025 2:49 pm ] |
| Post subject: | Re: 225 Slant Six Industrial Knock |
Knock knock! Who's there? Rod! Rod who? Rod Bearing! After listening to that video on headphones, my guess is that it is time to pull the engine and at the very least replace one rod bearing, if not go all in and do a full rebuild. |
|
| Page 1 of 1 | All times are UTC-07:00 |
| Powered by phpBB® Forum Software © phpBB Limited https://www.phpbb.com/ |
|