98 explorer replaced motor

Hello all,
recently I replaced the motor out of a 98 I picked up really cheap. I found another motor out of a 98 and replaced the two timing chain tensioners. The one on the rear and the one on the top of the motor. I got in it after the install and it started up sounded good! But driving it home it started rattling and running rough. And at low idle it seems to want to die. My question is, is it possible to put the tensioner in too tight that it makes the chain bind a bit? Or does it sound like something worse? As i rev the engine the noise gets worse.

Ok so I haven't gotten any responses yet... but I have read that there are several part numbers for timing t ensioners. Is it possible that if I put the wrong one in the front it would cause the chain to be too tight? That is what it seems like it is doing... it seems to be binding. Oh I have a 4.0 Sohc vin e.

Hi, got the same problem when i changed the lover back tensioner, lost my idle direct. And when I tryed to press down the old one, there was just possible to press it down to half, then it was almost solid.

Have not changed the upper one yet, to much work so I going to get it replaced at a garage later.

Any reflection of the old one you did take out, was it really hard or soft to press down?
Or have you got any other solution yet?

Best regards Mats / Sweden

hydraulic tensioners

The new Ford camshaft timing chain right (rear) and left (front) hydraulic/spring tensioners have weaker springs than the original ones. The springs keep the chain taught until oil pressure builds after engine start. Some of the aftermarket tensioners available on eBay are just junk. The piston can seize in the bore shortly after engine start. If the piston seizes in the extended position the chain will break. If the piston seizes in the retracted position the chain can slip. New tensioners should be manually checked before installation. Oil the piston and then check for free movement by depressing and releasing the piston several times with your thumb. I used to recommend replacing the tensioners every 75K miles. However, now that the springs are weaker I doubt that it's worth the effort and cost. In my opinion, the best solution for extending the life of the timing chain related components and the engine bearings is a pre-oiler.

Thanks for a really good advice, for sure I will follow it
Have a nice day //Mats

Happy tough that I found one hose on the aircleaner that was not connected, when re-connected I got my idle back again.
But it seems like it rattel when I start up after changed one of the tensioners, hopefully it will be better when I got the upper one changed.
Any one who got any experience of who of them use to be causing most noice in startmoment?