Bad miss with popping on top end

[Tbill98]

I have a 94 ram 1500 with a 3.9L and a 5 speed manual. I recently replaced the clutch in it and while i had the engine out, I put a timing set and tensioner in because it didn't come factory with one. Once i got it back in the truck and hooked everything back up, and fired her up it started shaking real bad and on acceleration it has a pop in the top in. Checked for vaccum leaks and replaced the crank sensor with no avail. And the timing marks got lined up exactly where they were when i took it apart. Could the tensioner cause the timing to be a tooth off? Any help/advice would be appreciated.

 

[BlackMagnum2000]

I'm not too familiar with the 3.9s but I know on the V8s it's common to damage the crank sensor when pulling or putting in the engine because it's located at the very back of the engine, at the top, right at the bell housing. You could check to see, assuming it's located in the same place, if it's damaged. Also could check cam sensor. You didn't have the distributor out did you? As for the timing itself, someone else can most likely help you better than I.

 

[Rustycowl69]

Did you say you put a tensioner on the timing chain, where it never had one? If that is true, how and/or why would you do that?

 

[Tbill98]

I replaced the crank sensor. And didn't have the distributor out. As for the tensionor. I put it in because it would go through chains faster than most other vehicles. They had the provisions already there for it. All I had to do was remove the plate at the end of the cam and the oil along plate and it bolted right on. Every engine 95 and after came with tensionors in then. Only certain engines before that had them. Mine just wasn't one

 

[Rustycowl69]

Ok, I checked my 01 service manual, and the only small block shown with a tensioner is the 3.9L. So not all engines after 95 came with the tensioner. Why in the world would a 3.9L call for a tensioner, whereas a 5.2L, 5.9L, 8.0L not. Maybe it's because there's not enough parasitic drag on the cam and chain to keep the chain in tension? I don't know, maybe, I'm not a mechanical engineer. If that were the case, maybe going to heavier valve springs might help. Anyway, as long as you lined up the timing marks correctly rotating the crank in the forward direction, when you checked them, and then rechecked them after you engaged the tensioner, that shouldn't be the issue.
You said you've gone thru many timing chains, how many, and how many miles? Is there an oiling issue? Have you tried going to a double roller chain and sprockets? Do they make double roller sets for Magnum engines?

 

[dapepper9]

Ok, I checked my 01 service manual, and the only small block shown with a tensioner is the 3.9L. So not all engines after 95 came with the tensioner. Why in the world would a 3.9L call for a tensioner, whereas a 5.2L, 5.9L, 8.0L not. Maybe it's because there's not enough parasitic drag on the cam and chain to keep the chain in tension? I don't know, maybe, I'm not a mechanical engineer. If that were the case, maybe going to heavier valve springs might help. Anyway, as long as you lined up the timing marks correctly rotating the crank in the forward direction, when you checked them, and then rechecked them after you engaged the tensioner, that shouldn't be the issue.
You said you've gone thru many timing chains, how many, and how many miles? Is there an oiling issue? Have you tried going to a double roller chain and sprockets? Do they make double roller sets for Magnum engines?

They do and i would definitely look at doing that

 

[Tbill98]

I have a double roller on it i do believe now. and i didnt check after the tensionor was on at the marks. i was in a hurry and forgot. ive had the truck for 3 years and this is the third one put on in the last 5 years. the truck on the other hand has 1.2 million miles on it (Dont believe me if you wish. not the first time ive heard it) so it was definitely time for a rebuild. Fixed all of the oiling problems as well so i know thats not the problem. I guess all i can do is tear it apart again and check the marks again.

 

[SportRam00]

I would verify you have everything connected properly. Also, check to make sure your distributer is wired properly. I had some plug wires reversed the last time I really tore into my truck. It would run, but not well. Very similar to what you may be experiencing.

Try the simple things first, before tearing your hair and your engine out again!

 

[dodge dude94]

1.2 million miles out of a half ton is quit the achievement. Pics? Lol

 

[Tbill98]

Checked and double checked everything. fixing to just tear off the timing cover and check my marks. i think im a tooth off. and ill upload some pics later. I dont have any on my phone anymore.

 

[Gr8bawana]

1.2 million miles out of a half ton is quit the achievement. Pics? Lol

1.2 million miles? Holy crap! It does give me hope since I have 249,000+ miles on my 1997 5.9 gas engine.
Still original engine and trans never opened or rebuilt and never touched the plenum gasket.
I must be incredibly lucky.

 

[Rustycowl69]

Man, I thought turning 300K on a couple of my Jeeps was an accomplishment! That's nothing compared to 1.2M. Good job!

 

[Tbill98]

Found the problem. The flywheel they said was for the truck was the wrong one. It was for a v8. Got a new one on the way. And my egr valve is bad as well. Thanks everyone for the help. If I still got issues after I fix all this I'll be back.

 

[Tbill98]

And Gr8bawnana I keep the oil changed every 2000 miles or every 2 months. And just keep routine maintainace up. There's no reason anyone with one of this trucks can't get over a mil

 

[IrocRam]

I think as long as you don't get a lemon from factory or internal parts that are faulty or weak either by chance or a certain time span of manufacturing, any vehicle can make it pretty far. If you drive your vehicle gently and maintain it very well, and live in a good environment, I could see half a million from a lot of engines. 1.2 million miles on an original motor though, is impressive.