Manual Cam Chain Tensioner Install

[donalds]

Yes you can tighten them up I would

 

[C420sailor]

How long does it rattle for on start?

 

[BTR]

@C420sailor - On startup, it rattles approximately 1 second and then the rattle goes away.

 

[allmyEXes]

These are the Polaris instructions. Start at step 6). Ignore the counter clockwise Polaris instructions.
On my 4.0 63k plus ago, I did such. Before locking the nut down the tensioner should be tightened a 1/4 to 1/2 turn.
Remember that the Polaris chain is probably shorter than the 4.0 Ford chain. @410Fortune Jamie could say for sure on the Polaris info.
It's been a while since I have done this but after install, I think that I cranked it up, took note of where I had the adjustment, backed off of the tensioner part to see what it sounded like then tightened it back to my first adjustment and then locked the nut. I wanted to see what it sounded like if it were too loose. I could feel it in my fingers and could hear it to loose.
Instructions are from RZRforum.net
Instructions are for either XP 900 or XP 1000:


1) Blow out the Spark Plug Holes and The top of the Valve Cover

2) Remove the Valve Cover

3) Remove the Spark Plugs

4) Remove the Clutch Cover

5) Rotate the Primary Clutch "COUNTER CLOCKWISE ONLY" (Never Turn Engine
Clockwise) until the (E's) on the Exhaust Cam Gear and (I's) On the Intake Cam Gear line up horizontal with the top edge of the head

6) Verify TDC (Timing Mark is on the flywheel)

7) Remove the stock tensioner

8) Put a very minute amount of sealer on the Mechanical Tensioner threads

9) Remove your metal seal from the stock tensioner and install it on the Mechanical Tensioner

10) Thread the Mechanical Tensioner all the way into the cylinder and tighten the tensioner with a wrench

11) Tighten the center adjuster bolt as far as you can by hand then turn it another 1/4-1/2 turn more with a wrench and tighten the lock nut with a wrench.

Greg in north Alabama

 

[BTR]

@allmyEXes - That's interesting. Many/most posters here recommend finger-tight and then LOOSEN the adjusting pin 1/4 turn before locking it down. However, according to the info you posted, it's recommended to TIGHTEN the adjusting pin 1/4 - 1/2 turn before locking it down.

 

[allmyEXes]

Yep! On my '97 install, I had part of it all still disassembled for access. Radiator was in but fan and shroud were still out, and the serpentine belt was not on so that I wouldn't injure myself with it running.
Link to RZR page

 

[BTR]

As a next step... to see if I can get rid of 100% of the startup rattle... I'm considering doing the following:

1. Rear Tensioner - Tighten 1/4 turn, lock down, start engine to evaluate startup rattle.
2. If needed, do the same on Front Tensioner.
3. If needed, repeat on Rear Tensioner.
4. If needed, repeat on Front Tensioner.

If I do all 4 steps above, then I've tightened both tensioners by 1/2 turn each. At this point, I'd be scared to do any further tightening.

 

[allmyEXes]

@BTR I went back and found my old engine repair thread for the white'97 Explorer 4.0 and I did not have the thermostat housing back in place
yet so that I had working room for adjustment of the manual tensioner used on the front.

1997 "white" 4.0 SOHC primary and D side secondary chain guide repair-Several pressing June 2025 repairs-

The alternator positive. Cable routs behind the power steering / ac compressor bracket Their is a path for the wire The wire should have a plastic shield that will line up perfectly make sure you don't pinch it I did

www.explorerforum.com

 

[BTR]

@410Fortune - I’m curious to know your opinion on my posts #40 and #47. I not confident on how to proceed… I don’t know what to do next. I want to get things squared-away properly, but I also don’t want to break anything nor create any downstream problems. I’d appreciate hearing your thoughts. Many thanks!

 

[C420sailor]

It’s hard to say without knowing the state of the cassettes.

If the clatter is because of cracked or damaged cassettes, tightening may help…or it may make things worse by putting more stress on them.

That said, I don’t think it can hurt to tighten them a hair and run it quick just to see. I wouldn’t use anything more than fingers on a socket though. 1/4 turn at a time, tops. If you need a wrench to tighten….ehhhhhhhhh

Mine don’t make any noise on start. Zero.

 

[410Fortune]

Finger tight. To me this means tighten it with two fingers holding the socket, tight until the socket slips between your fingers.
Then one more 1/4 turn and lock it down

I don’t do it with the engine running

Then start engine and see how she behaves

Finger tight, then 1/4 turn…then lock it down
Keep it simple
Easy to overthink these things

If your cassette is already damaged then…
It may never get all the slack out no matter tight you pre tensioner the chain

 

[BTR]

2000 XLT 4DR 2WD. 4.0L SOHC JOB 1 (VIN E). 5-Speed Automatic O/D 5R55E. 158,000 miles.

Thanks everybody (@allmyEXes, @donalds, @C420sailor, @410Fortune)! I appreciate your insights and advice! Very helpful!

Since I still have a small amount of chain rattle on startup… it lasts about 1 second and then goes away, it’s much, much quieter (a lot less growly) than it was before, and I have no rattle when accelerating (1,500 > 2,000 > 3,000 > 3,500 RPMs), I think I’m going to do the following:

• Have a helper start it up while I listen with my stethoscope. Hopefully, I can determine which chain (front or rear) is rattling.
• Since I did finger-tight (with the engine running) and then backed off by 1/4 turn before locking them down, I’ll add 1/4 turn of tightness.
• Start it up and evaluate for chain rattle.

I’ll report back with results.

 

[donalds]

Start with the back

 

[Fix4Dirt]

This is a 'tard question but I can use the same for F/R tensioners right? Planning to order em tomorrow hopefully.

 

[C420sailor]

Yep

 

[Fix4Dirt]

Yep

10-4!

 

[410Fortune]

Get the extra long version I posted will work better on passenger rear head

 

[BTR]

This is a 'tard question but I can use the same for F/R tensioners right? Planning to order em tomorrow hopefully.

Yes. I used the Alpha Rider Cam Timing Chain Tensioner Manual W/Gasket For Polaris Ranger 1000 RZR 570 XP 900 ACE Stainless Steel from Amazon ($16.99 each). They fit/worked on both the front and rear.

 

[BTR]

2000 XLT 4DR 2WD. 4.0L SOHC JOB 1 (VIN E). 5-Speed Automatic O/D 5R55E. 158,000 miles.

After installing front and rear manual tensioners… finger tight with the engine running, then backed-off by 1/4 turn and locked down… I still had a small amount of chain rattle on startup. The rattle lasted a short 1-second, went away quickly, and was much, much quieter (a lot less growly) than it was before replacing the tensioners. I had no chain rattle when accelerating (1,500 > 2,000 > 3,000 > 3,500 RPMs).

To get rid of the remaining small amount of startup chain rattle, I tightened the rear tensioner by 1/4 turn. Now, there is NO CHAIN RATTLE ON STARTUP.

Mission accomplished.

 

[allmyEXes]

Post #44.