datzenmike Posted January 12, 2023 Report Share Posted January 12, 2023 The only stupid thing is to not ask questions. You can learn by reading or experience, but knowledge is faster if you ask questions. If in gear with rear wheels locked so they can't move then nothing in the transmission can move either this includes the clutch disc that is splined to the input. The engine, flywheel, pressure plate and release bearing are spinning and straining to turn the transmission but it can't. 1 Quote Link to comment
raythomas Posted January 13, 2023 Author Report Share Posted January 13, 2023 (edited) 10 hours ago, datzenmike said: The only stupid thing is to not ask questions. You can learn by reading or experience, but knowledge is faster if you ask questions. If in gear with rear wheels locked so they can't move then nothing in the transmission can move either this includes the clutch disc that is splined to the input. The engine, flywheel, pressure plate and release bearing are spinning and straining to turn the transmission but it can't. Man I'm sure glad you cleared that up for me. All I could think is here I have almost gotten the trans back in and then find out I should have done something else different and end up pulling all that mess back out. Dang I'm glad I don't have to do that. Of coarse never say never cause I will have to take it back out if I have to remove the engine. Or at least it looks like it would be easier to get it out that way. Thx Ray Edited January 13, 2023 by raythomas 1 Quote Link to comment
raythomas Posted January 15, 2023 Author Report Share Posted January 15, 2023 (edited) Latest Update: Well I got everything back together and when I tried it, wouldn't you know, the noise is still there. Which is kinda crappy cause that mean's I took the trans and clutch out for nothing. Will loosen alternator in a day or so and remove the engine drive belt. Gonna try it with all the stuff on front of the engine not turning and see if noise goes away or at least changes. After that I'm at a total loss of what to do next. I really am. Thx Ray Edited January 15, 2023 by raythomas Quote Link to comment
datzenmike Posted January 15, 2023 Report Share Posted January 15, 2023 It's not a loss, you've a list of things confirmed not to be the cause. Quote Link to comment
paradime Posted January 15, 2023 Report Share Posted January 15, 2023 X2 on what Mike said. While you got everything off the front, if the knock persists, go BFH on the pulley nut to see if it changes the sound at all. Big F'n Hammer that is. Quote Link to comment
datzenmike Posted January 15, 2023 Report Share Posted January 15, 2023 On 1/6/2023 at 5:42 PM, raythomas said: UPDATE: 1-6-2023 Well I drained the oil, took off the cross member and removed the oil pan. And found absolutely nothing other than this tiny bent spring. And I know that little thing wasn't making noise. All the cylinder walls looked good so wrist pins haven't moved. All the cap and rod bolts were tight, so nothing loose there. There was no play in any of the rods. There was no slack in the pistons fitting the bore. Oil pick up tube bolts were tight and the screen and oil pick up tube looked fine. And I could see no scaring or rub marks anywhere in the crankcase. If you thought I was stumped before, well multiply that by a gazillion!! They may have tight rod bolts but the clearance is the thing. It's under 0.002" or half the thickness of newspaper. You can't see if it's opened up above specification and in the process of getting worse without removing the cap and inspecting them. At least put some plasti gauge on the cap and torque to spec, remove the cap and look at the crush pattern. Plasti gauge is an accurate thin wax thread that is flattened by the rod bearing when tightened. The flattening pattern is then compared to a scale to get the clearance. A flatter crush is a closer clearance and a narrower crush is a wider clearance. If this is the cause of your noise it's still early and the clearance has definitely got larger, but you can't tell without closer examination. 1 Quote Link to comment
Stoffregen Motorsports Posted January 15, 2023 Report Share Posted January 15, 2023 Tom and Ray Magliozzi used to say - if you can't find the problem, keep driving it and the problem will be made apparent. Paraphrasing of course, but the point is, if you give up now, at the point of still having to check the rod bearings for wear, you could find out the hard way that it was in fact rod bearing wear. Finding out the hard way means a full engine rebuild. Quote Link to comment
datzenmike Posted January 15, 2023 Report Share Posted January 15, 2023 I think I mentioned that if early enough it may only be the excessive bearing clearance that makes the hammering noise under load. With luck the crankshaft isn't damaged and only the bearing(s) need replacing. When at the correct clearance a layer of oil takes the pounding and prevents metal to metal contact, but as the clearances open up, the rod pushes this oil layer out to the sides and just hammers the soft bearing making it worse and worse. It's one way, from bad to worse, to spun bearing, ruined crankshaft and rod, to seized rod welded to crankshaft. At highways speeds the rod snaps off and spinning crankshaft pounds it through the block wall. 2 Quote Link to comment
Stoffregen Motorsports Posted January 15, 2023 Report Share Posted January 15, 2023 Yes, catch it early and spend $100 on bearings. You could replace them in an afternoon. Wait too long and throw the motor away. 1 Quote Link to comment
raythomas Posted January 16, 2023 Author Report Share Posted January 16, 2023 13 hours ago, datzenmike said: They may have tight rod bolts but the clearance is the thing. It's under 0.002" or half the thickness of newspaper. You can't see if it's opened up above specification and in the process of getting worse without removing the cap and inspecting them. At least put some plasti gauge on the cap and torque to spec, remove the cap and look at the crush pattern. Plasti gauge is an accurate thin wax thread that is flattened by the rod bearing when tightened. The flattening pattern is then compared to a scale to get the clearance. A flatter crush is a closer clearance and a narrower crush is a wider clearance. If this is the cause of your noise it's still early and the clearance has definitely got larger, but you can't tell without closer examination. Well I guess I could kick my own arse. I should have done this when I had the stupid oil pan off the motor last week🤦♂️ Live and learn I guess. Thx Ray 1 Quote Link to comment
raythomas Posted January 19, 2023 Author Report Share Posted January 19, 2023 Checking in . Been a hard week at work and I haven't even felt like going to the garage at night. Maybe this weekend. ho hum Thx Ray 2 Quote Link to comment
raythomas Posted January 29, 2023 Author Report Share Posted January 29, 2023 Hey Fellows. Dumb question, but is it possible to run the engine with the valve cover off so you can watch the rocker arms and timing chain? Or will it blow and or spill oil all over the place? Thx Ray Quote Link to comment
datzenmike Posted January 29, 2023 Report Share Posted January 29, 2023 On a Z series I would think so. Warm the engine so the oil is thinnest and run only at idle. If it's going to throw oil, the timing chain at the cam sprocket is the most likely place. Expect it. Quote Link to comment
bilzbobaggins Posted February 11, 2023 Report Share Posted February 11, 2023 Just checking in. I love a good mystery. Quote Link to comment
raythomas Posted February 18, 2023 Author Report Share Posted February 18, 2023 Hey fellows Sorry to report that my job has kept me turning flips for nearly a month. I haven't had a chance to get back into the garage to even lay hands on the D21. After work each night, I'm too dang tired to even want to. Will try again in the next week or so I hope. Ray 2 Quote Link to comment
raythomas Posted March 5, 2023 Author Report Share Posted March 5, 2023 UPDATE:.......FINALLY!! After nearly a month I finally got some time to work on the truck again. This morning I pulled the front cross-member and oil pan. Removed the oil pickup assembly and used plastigage to check all the bearings. Well so far so good. All bearings were in spec and looked good. Only problem is, now I can rule that out for the noise but still haven't found where it's coming from. I plan on taking the alternator loose in a day or so and removing the drive belt so the alternator, fan or water pump isn't moving. Then drive the truck down the end of the road and back and see if the noise is still there. If anyone else has any ideas, I'm all ears. Thx Ray 1 Quote Link to comment
datzenmike Posted March 5, 2023 Report Share Posted March 5, 2023 Don't go far and take your tools. That drive may be enough to over heat. Alternator and water pump are good candidates for noise. Also look at the alternator mount on the block. 1 Quote Link to comment
raythomas Posted March 5, 2023 Author Report Share Posted March 5, 2023 15 minutes ago, datzenmike said: Don't go far and take your tools. That drive may be enough to over heat. Alternator and water pump are good candidates for noise. Also look at the alternator mount on the block. What should I be looking for on the alternator mount? Is that an area prone to weakness or problems? And it's not a far trip down the road and back. Maybe less than 1/2 a mile round trip. Surely it shouldn't overheat in that short of a distance? Thx Ray Quote Link to comment
EDM620 Posted March 5, 2023 Report Share Posted March 5, 2023 1 hour ago, raythomas said: UPDATE:.......FINALLY!! Only problem is, now I can rule that out for the noise but still haven't found where it's coming from. I plan on taking the alternator loose in a day or so and removing the drive belt so the alternator, fan or water pump isn't moving. Then drive the truck down the end of the road and back and see if the noise is still there. If anyone else has any ideas, I'm all ears. Thx Ray Maybe you can post a video with the noise it's making. The actual sound should help others with the diagnosis Quote Link to comment
raythomas Posted March 5, 2023 Author Report Share Posted March 5, 2023 (edited) 8 hours ago, EDM620 said: Maybe you can post a video with the noise it's making. The actual sound should help others with the diagnosis If my memory serves me correct I think I did post some .mp3 clips a few pages back. But yes, I had planned to record it again when I do the test run with the drive belt off the motor so the alternator, fan and water pump aren't turning. Maybe listening to my noise may jog someone's memory. I hope. Thx Ray Edited March 5, 2023 by raythomas 1 Quote Link to comment
datzenmike Posted March 5, 2023 Report Share Posted March 5, 2023 The mount had 3 bolts and are not known for coming loose. Can't discount it till you check. The L16/18s were 2 bolt and they did come loose. I had a 521 and it snapped both bolts off from the vibration. Old ears, but I couldn't make out any sound not made by the average L series. Quote Link to comment
raythomas Posted March 8, 2023 Author Report Share Posted March 8, 2023 Does anybody know what kind of gasket if any goes between the oil pick up and the block? Mine looks like it had some kind of "sealant" but not sure it was an actual gasket. I've looked all over the net and can't really find any part number for a gasket for it. Was curious if you guys know. Thx Ray Quote Link to comment
thisismatt Posted March 8, 2023 Report Share Posted March 8, 2023 Dipstick tube? Just pressed in 1 Quote Link to comment
Crashtd420 Posted March 8, 2023 Report Share Posted March 8, 2023 Or are you talking about the pickup tube in the oil pan.. if so yes it has a typical flat gasket... I believe it's with any gasket kit you buy.... Quote Link to comment
Crashtd420 Posted March 8, 2023 Report Share Posted March 8, 2023 Not necessarily the one you need, I'd have to search more, but it will look like this.... Quote Link to comment
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