rod knock in # 1 anit no more ???????

[JimGT]

Put your thinking caps on...I went around a left hand corner motor started to shake like it was running on 3 cylinders and had a definate knock. From what everyone thought it was hole #1. It's been this way now for 2 weeks. I was so sure motor was shot, so I got a new one in the back of my truck waiting for Friday when my stage 2 Comp cams arrive, my wife just got home from in town and said "Honey, Honey, your knock is gone!" I smacked her in the eye and told her to quit lying But to my surprise I went out and started it and sure enough no knock! At all! Went back in and said she was right so she socked me in my eye. She said right before the knocking quit it was running like it was on 3 cylinders and she heard a clunk. So what is this besides tough love? Spun bearing? But I mean no knock, not a tap, not a shimmy, nothing.

 

[Rick 91GT]

Stuck or clogged tensioner?

 

[Lugnuts]

So it has returned to "normal " operation? Restored power and everything? manual or auto trans?

 

[trinity_gt]

Sounds almost like something -- screw, nut -- got into the chamber and embedded itself in the piston crown. Then it -- or parts of it -- broke loose, jammed a valve open for a bit before being spit out.

When you say it felt like it was running on 3 cylinders, do you mean that it literally felt like 5 were dead or was it that it felt like 1 one was?

Pull the plugs and check the electrodes. They almost always get pounded by debris in the chamber. If you or someone or some shop you know has a borescope, see if you can borrow it and peer into the suspect cylinder(s) to look for witness marks on the piston crown.

 

[JimGT]

Its the second time I've heard tensioner. Firing on all 8 cylinders. I'm afraid to put my foot in it to see if it pulls like it use to. But it sounds good. There hasn't been nothing taken apart since I've owned it to allow any loose parts to get into chamber. It sounds to me like a main bearing flip flopping but I haven't lost any oil pressure. Should I put my foot into it to see if it pulls or wait until my new motor is ready to be put in? I hate to mess up a good thing. Like I said it all started by making a left hand turn under normal load. (If that makes any difference) When I say running on 3 cylinders that's an exageration maybe more like 6, with my shifter shaking left to right.

 

[mransr]

before you do anything else (especially putting your foot in it) I'd HIGHLY recommend pulling the plugs and checking them for damage or one that is obviously different.

 

[JimGT]

Pulled all the plugs, all looked good. No wet ones no bent ones no white ones......Still runs strong, And still starts to shimmy and shake and valve tran makes all kinda noise when I get in it for too long. Not to hard, but for too long of time, Lets say 1-2 minutes. I can spin them and bump the rev with no harm. But let me stay in it for two turns doing donuts, even a straight run down the road for like I said a good minute or 2 and it all goes to ****. I ease up and bring it down to 1k or what ever and in the same amount of time, 1 or 2 minutes it stops shaking and shimmering. And I go 70-80 mph daily down the highway to work no problem. Like I said taking off stretching each gear I'm lucky to get into fourth or fifth before it starts the death wobble. Lucky guess...fuel starvation...And whatever happened to the knock? (Not that I miss it) Or is the oil pump losing prim. I just have stock gauge in it. And yes, i have added some motor hony

 

[JimGT]

the oil pump is shot. goes to reason. i hear thay go out about 100k this one has 120k. am pulling it " the engine" this weekend and putting the one i camed with springs and oil pump in. the old will make a good back up with a new pump on it..