Rod Knock After T-Belt Install???

[Lil John]

Hey everyone. I have some questions regarding what sounds like a rod knocking. I'm currently working on a 95 Talon TSi with the lovely 7-bolt. The car was brought to me with the timing off. It jumped timing but somehow didn't bend any valves. It actually somehow ran but had no power whatsoever (obviously). I'll give you some quick background on this motor. The kid that brought me the car, purcahased the motor out of state from a guy that said it was out of a 99 2G. But we ran the VIN and it came back as a 95. So, the guy he bought it from lied to him about that. Anyway, the kid swapped in the block that he bought into his Talon. He didn't touch the bottom end at all, he only took one of the rod caps off to check the bearing. He said it looked fine, and reinstalled it. He never touched the front case (oil pump) either. He got everything installed and finally got it running, but it ran like crap (because of the timing being off). So, he didn't want to mess with it anymore, and brought the car to me to fix.

Well, I redid the timing and aligned everything properly. One thing I did notice, was that the oil pump sprocket didn't spin very freely. I could spin with my fingers but there was some resistance. I tried to point the arrow straight up to see which was it would rotate, but it just stayed pointing up. I know its suppose to rotate one way or the other to dertermine if its properly aligned. So, I ended up taking the plug out of the back of the block and sticking a screwdriver in there make sure it was right. The car did sit for a long time before I began working on it, so maybe the balance shaft bearings were just dry and didn't have very much oil on them. I don't know if this something to worry about or not.

I got everything put back together and then goto start it. It starts right up and idles and revs up good except for the knocking noise that seems to be coming from the bottom of the engine. It sounds like its coming from the first or second cylinders. It started knocking as soon as you start it up. As it warms up its not quite as loud and also, as you rev it up its also not as loud. The stock oil pressure gauge barely shows any oil pressure. Other than the knocking it runs great. We obviously didn't run it very long.

Could it be a rod bearing which isn't allowing the engine to build hardly any oil pressure? I do know that I'm getting oil to the top of the head. It sounds like it could be coming from the same rod bearing that the kid took off to check before he put it back together. Could the oil pump have gone bad just like that? It didn't begin to knock after it was running for awhile. It began to knock as soon as it started it up the first time.

We are going to pull off the oil pan and take a look. I guess we will know for sure then. Does anyone have suggestions? Thanks for the help.

-Jason

 

[gthompson97]

you better pull off the pan and check that rod cap that the kid pulled off. sounds like he screwed something up when he messed with it and now it's knocking. i'd check that ASAP because if it runs too long (even the slightest little bit) it could severly mess up the crank journals and/or rod journals. i'd pull off ALL the rod caps and check all the bearings and journals just to be safe.

 

[BISHILVR]

Make sure that you did'nt put the cap on backwards.

 

[TurboChrged93]

Over-torqueing that cap is a possibility. Also. Check your timing. Check your timing. Check your timing. Time and time again. Or... the guy might have sold it... because it KNOCKS?!?!?!

 

[Lil John]

Over-torqueing that cap is a possibility. Also. Check your timing. Check your timing. Check your timing. Time and time again. Or... the guy might have sold it... because it KNOCKS?!?!?!

The timing is dead on as far as having all of the timing marks lined up. I didn't set the basic ignition timing because I was afraid to run very long and do even more damage. I don't understand why the timing would have anything to do with the knocking sound. The car has a steady idle. Its idling high right now (around 2000rpm) because obviously I didn't want to let it run long enough to warm up and correctly set the curb idle. It also revs fine too. So, I don't think its timing related. I'm not the one took off the cap, so I can't say for sure what it looked like or if it was reinstalled correctly. I guess will see when we pull off the pan and take a look. Thanks for the input.

-Jason

 

[chaclark83]

something else to check is the timing belt tensioner. If the seal is messed up in it it will just sit there and bounce in and out as the belt tension changes from the valves opening and and closing. also the blade that sends the signal to the crank sensor may be bent. Mine recently got bent on a timing belt swap and sounded exactly like a rod knock when it hit the crank sensor.

 

[Lil John]

something else to check is the timing belt tensioner. If the seal is messed up in it it will just sit there and bounce in and out as the belt tension changes from the valves opening and and closing. also the blade that sends the signal to the crank sensor may be bent. Mine recently got bent on a timing belt swap and sounded exactly like a rod knock when it hit the crank sensor.

If you're talking about the auto tensioner, which I think you are, I did replace it. As far as the crank sensor blade, I'm almost positive thats not it. I turned the motor over several times by hand (ratchet) after I installed the timing belt without problem. If it was hitting the crank angle sesor I'm guessing that it would make it difficult to turn over by hand. Also, before I did actually try to start the car, I pulled the fuse so I could crank it over a couple times first without starting it. During the time it was cranking over, I didn't hear any knocking sound. Only when the car was actually runing. I'm sure it make noise regardless of running or not if it was hitting. Would the car even run if it was hitting like that? Thanks for the input.

-Jason

 

[Lil John]

I was just down at the shop and was looking over somethings. The timing is still dead on, but I did notice that the tensioner pulley has some play to it. You can move side to side a little bit if you move the belt side to side. There is also a little up and down play. So maybe thats moving around and casuing the noise. I'm going to replace it today and see what happens. It might not be the problem, but the pulley is definately needs to be replaced.

 

[Strm Trpr]

Lil John,
Is the knock you're hearing rpm dependent?
Does it seem to be on pace with the crank, or is it knocking faster.
The reason I'm asking this is because the balance shafts spin twice as fast as the crank.
You obvisously know your 4G63's, so mentioning that the rear balance shaft is ran off of the oil pump isn't really necessary, but I said it anyway.
You mentioned in your first post that the oil pump sprocket was tough to turn by hand, and that it wouldn't fall down like it should, that to me indicates somethings wrong with the oil pump/rear balance shaft.
Also, you mentioned that the oil pressure was weak, again pointing to the oil pump/rear balance shaft.

I hope this kid is paying you one way or another, cause it sounds to me like you should remove the timing belt and remove the front case and see what's up with the oil pump....

When you drop the pan, check the rear balance shaft.
You should be able to see it, push up/down on it and see if the rear bearing is worn out.
I know this will cause knocking that sounds a lot like rod knock....

 

[chaclark83]

even if it is a new auto tensioner if it is compressed to fast it will destroy the seal causing it to move in and out to make a knocking sound to answer your question yes the car will run with the blade bent mine ran like that for 3 weeks before i got off my lazy ass and fixed it.See if you can press the little piston in on the auto tensioner with your hand.