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SOHC V6 Timing Chain Saga

So I replaced the left cassette and jackshaft guide/tensioner. Everything seems OK except for the camshaft guide (where the hydraulic tensioner pushed on it) seems to be vibrating back and forth more than it should be for some reason. I replaced the hydraulic tensioner (Ford part) last year.

Could it be that the tensioner isnt putting enough pressure on the chain to keep it tight?

I opened the oil cap and I can see the part (of the guide) that the tensioner pushes on vibrating quite a bit and I can hear the chain slapping, although not that much. When the rpms go up, it quiets down to where you cant hear it at all and everything seems smooth.

Whats going on at idle that could be causing the tensioner to not work properly. Im stumped here. I put 20 in/lbs of torque on the tensioner before I torqued the camshaft bolt down. What am I missing.

Should I replace the hydraulic tensioner?
 



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cassette guide movement

So I replaced the left cassette and jackshaft guide/tensioner. Everything seems OK except for the camshaft guide (where the hydraulic tensioner pushed on it) seems to be vibrating back and forth more than it should be for some reason. I replaced the hydraulic tensioner (Ford part) last year.

Could it be that the tensioner isnt putting enough pressure on the chain to keep it tight?

I opened the oil cap and I can see the part (of the guide) that the tensioner pushes on vibrating quite a bit and I can hear the chain slapping, although not that much. When the rpms go up, it quiets down to where you cant hear it at all and everything seems smooth.

I've never watched my cassette guide at idle to see how much it moves. I do know that when I rotate the crankshaft manually there is considerable movement because the valve spring compression interacts with the camshaft lobes. At certain positions the traction side of the chain goes slack. When the engine is rotating rapidly the chain should stay taught on the traction side. The oil pressure in the tensioner piston is what keeps the chain taught. The mechanical spring is not strong enough. How is your oil pressure at idle? The chain should not slap at idle with good oil pressure. What weight oil are you using? Is it synthetic?

. . . I put 20 in/lbs of torque on the tensioner before I torqued the camshaft bolt down.

Was this to make the chain taught before tightening the camshaft sprocket retaining bolt because you didn't have the tensioner tool in the OTC 6488 timing kit? Tensioning the chain before torquing the camshaft sprocket bolt has an effect on the camshaft timing relative to the crankshaft but should have no effect on chain slap.
 






Valvoline 5w-30 regular ole' oil. What Ive always used since the day I bought it.

Well what I did was epoxy my old tensioner together so that the piston wouldnt move and then I tightened it to 20 in/lbs or so and THEN torqued the camshaft sprocket bolt to 63 ft/lb. I was SURE the camshaft did not move (as it was marked) and TDC was achieved as well. Yes I did this without the OTC tool. I did not loosen the jackshaft bolt. I was able to remove the cassette guide lower bolt with a 10mm wrench. Had fun getting it back in though. :)

It sounds like chain slap but when i looked in there with the oil cap off, It doesnt look like the chain is slapping around. The camshaft guide just bounces back and forth a lot more than I thought it would.

Im not sure what my oil pressure is. Dummy gauge says its normal.
 






2000StreetRod, thank you very much for all you have done to make this easier for other (me) to do this by themselves. This was the craziest thing I have ever done to an engine, and to do it by myself over a span of 3 days is also crazy.

Also, for anyone with a balance shaft tensioner broken, you CAN replace it without raising engine or dropping axle (or whatever other options were). You DO however need a ton of patience, an assortment of rachets (small, medium, many extensions and flexing heads), heavy duty pliers, small(ish) hammer, torx bit set (star shape), um, MORE PATIENCE.
It takes a long time, but it can be done and it worth it for what I fished out of my engine. One piece was directly under my main timing chain and if that decided to finally move up and between moving parts I thing I would of had a huge issue.
Once upper pan drops, scoot it over and it will lean to 1 side more and gives you enough room to slowly bend down side wall on the tensioner so then you can wiggle in just the tensioner blade into old bracket. Make sure to scoot the blade into the slot and reason for bending wall is so you can insert the blade hole onto the pin of old bracket. Small hammer to tap lightly the metal wall back up. Don't touch the chain, oh, and of course take out the guide to help give you enough slack in chain. Then putting it all back together, ugh, takes so much time to align it up, and I just pray that everything holds up and I dont get any leaks, almost 48 hours later I drove it an hour and, still looks good. See pics

thanks again to everyone who post on this site
Phil

184589_10200978956141836_2056006790_n_zpsc9c08968.jpg


just enough room

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here are the pieces I fished out of the engine. The missing middle piece was found months ago when I dropped my lower pan to see what I could find.
 






This thread has been so helpful in fixing my timing chain issue. thank you for posting your experience and your ideas to help people like me that has never dealt with a beast like this.
 






got the thing running using the techniques you posted [MENTION=111113]2000StreetRod[/MENTION] but i welded the old tensioners instead of jbweld. the truck fired right up on the first try.

Again this forum is the most helpful I've seen in years!
 






got the thing running using the techniques you posted [MENTION=111113]2000StreetRod[/MENTION] but i welded the old tensioners instead of jbweld. the truck fired right up on the first try.

Again this forum is the most helpful I've seen in years!


What's the technique for welding? I missed it somewhere?
I broke 2 pairs of chain guides this year. Today I removed the engine again (third time for the year) :))

I found a part of the old rear chain guide stuck behind the lower part of the cassette.
I plan to put a 4-5 sec timer relay to switch off the shock switch. It will give time to pick up oil in the lines.
Where I can find schematic of the oil lines? I plan to make it better.
 






Precision tensioner

What's the technique for welding? I missed it somewhere?

I think valchog is referring to an alternative precision tensioner for use when timing the camshaft.
TensTool.jpg

I made one by applying epoxy to an old tensioner to seize the piston in the cylinder. Apparently he welded the piston to the cylinder.

. . . I plan to put a 4-5 sec timer relay to switch off the shock switch. It will give time to pick up oil in the lines.
Where I can find schematic of the oil lines? I plan to make it better.

What is a "shock switch"? Are you planning to install an electric oil pump to pre-oil the engine prior to engine start? I installed an Accusump pre-oiler but I think now I would prefer an electric pump even though it means installing a port in the lower oil pan.
 






I think valchog is referring to an alternative precision tensioner for use when timing the camshaft.
View attachment 80949
I made one by applying epoxy to an old tensioner to seize the piston in the cylinder. Apparently he welded the piston to the cylinder.



What is a "shock switch"? Are you planning to install an electric oil pump to pre-oil the engine prior to engine start? I installed an Accusump pre-oiler but I think now I would prefer an electric pump even though it means installing a port in the lower oil pan.

I think he's talking about the inertia switch, which is simply inline to the fuel pump circuit. I think he means to delay the fuel pump turning on, to allow oil pressure to build from extra cranking.

I still have the Mallory oil pump to install, that's the best method to gain oil pressure before start up. Amsoil has a very expensive oil pump that is made to bolt to their bypass filter adapters, ending up with a near to $500 oil filter system.
 






Amsoil pump

I think Amsoil used to sell a small volume electric pump pre-oiler but I doubt it is still available. In my opinion, the best pre-oiler is an external electric pump that pulls oil from the pan and sends it to the filtering system. The pump should be automatically energized when the ignition is switched on and run only long enough until normal oil pressure is achieved. A manually controlled defeat and energize capability is also desirable. Oil pressure switch controlled enable/disable of the pump might also be useful.
 






I think Amsoil used to sell a small volume electric pump pre-oiler but I doubt it is still available. In my opinion, the best pre-oiler is an external electric pump that pulls oil from the pan and sends it to the filtering system. The pump should be automatically energized when the ignition is switched on and run only long enough until normal oil pressure is achieved. A manually controlled defeat and energize capability is also desirable. Oil pressure switch controlled enable/disable of the pump might also be useful.

That's the one I was referring to, I think they still list it as an option for their duel filter adapters.

This Mallory oil pump is a part number 4030, and is a stand alone unit, like their fuel pumps. I wish they still made it, I think it was around $140 when I bought it.
 






That's what I talk about - inertia switch. As I see the time for oil reach enough pressure while cranking is 3-4 sec. I don't think that is a problem for the starter. Electric oil pump is expensive for me so I'll try cheaper way. :)
Is the cold start the biggest problem in this engine?
what would happen if I make weld points on the cylinder of the tensioner so it can't move more than 3-4 mm?
 






Is the cold start the biggest problem in this engine?
what would happen if I make weld points on the cylinder of the tensioner so it can't move more than 3-4 mm?

I find that chain lash on start with the upgraded timing chain kit installed only really happens after the truck has been sitting for a week or so. Or if you change the oil filter without filling the filter with oil first.

Otherwise it's fine if you drive it every day, you have the oil gallery spacer fitted and you use an oil that's thin when cold. (Not 20w-50) more like a 5w-40.

That's an interesting way of thinking with preventing the tensioner from moving back into its self with weld marks. You probably want to make sure the ram doesn't stick back in there though if it does get forced back.

It might have been designed like that so it can move back if it needs to. Say with rapid engine deceleration the tensioner will move back in rather then putting undue force on the guides? I don't know.
 






Oil gallery spacer is only for the left head. I think it's because the tensioner is facing up.
Most of the cars have ratchet in the tensioner. Other Ford cars have it too. Why Ford make spring tensioner for this engine ... I can't understand.
 






volume restrictor

The "pencil" that goes in the oil gallery is a volume restrictor that reduces the volume of the chamber. Reducing the volume reduces the "dry start" time. With my Accusump pre-oiler the only time I hear start up rattle is after a total oil change that discharges the oil in the accumulator. That's another reason why I wish I had installed an external electric oil pump instead of an accumulator.

I agree that Ford made a poor decision in selecting the SOHC V6 camshaft chain tensioners. The OHV V6 had a hydraulic/ratchet tensioner as did the 4.6L V8.
OHVTensioner1.jpg

97DOHC4_6.jpg
 






Hello guys, after 8 months driving my Ford I didn't have any problems with the engine. :)))) I did my modification mentioned earlier. It takes 6-7 sec of crancking but the engine starts very smooth.
 






Oil pump gear issue during timing chain overhaul

Picked up an '02 Explorer XLS with good body and bad engine, figuring it needed a timing chain. (179k miles.) Leak down test confirmed cylinder 1 had no compression through 360 degrees rotation, so figured bent valve due to right (rear) timing chain problem.

Pulled engine, pulled valve covers and heads. Right chain guide shattered/destroyed, spewing debris. Interestingly, the rear jackshaft bolt was loose, such that there was no chain action on the right bank whilst turning the crank.

Both heads now at the machine shop for valve job incl. installation of the three new exhaust valves that were bent. NB: cylinder walls in extremely good shape as well as lower end, though I plan to replace rod bearings and piston rings for good measure.

Even though my Ex is 2wd, this puppy turns out to have a balance shaft. So I've returned the 3 X cassette Cloyes I had ordered for the 4 X (full) kit. I've removed the ladder/girdle/upper oil pan and thoroughly cleaned out oil p.u. screen, etc., of debris.

The oil pump (which I removed and disassembled to check for debris) is driven by an angled (worm?) gear that is found a couple of inches in from the back of the jackshaft (which I have removed and checked--seems fine). That gear engages a similar gear mounted on a short, thick vertical shaft that mounts to the top of the block with a circlip, into which a much smaller diameter "intermediate" gear/shaft runs down into the crankcase to dive the oil pump.

After removing the primary chain and left cassette, I re-inserted the jackshaft and bolted the front jackshaft sprocket back on in order to test the operation of the oil pump gears/drive (with the oil pump unistalled). I expected the worm gears to mesh/move smoothly. But they don't. As I turn the jackshaft with a E-20 socket on the front of the engine, there is a ratchety/resistance feel to the action.

Is this normal? I have no point of reference here. I'm concerned that even though the two worm gears appear undamaged, that the short verticle shaft somehow was bent, or that there may be a jackshaft bearing (are there jackshaft bearings?) may have been damaged. If this is supposed to move freely, w/o resistance, then I need to identify the source of the problem before I rebuild this block.

Any thoughts?
 






oil pump drive gears

I think the oil pump drive gears should move smoothly when rotating the jackshaft. Did you reinstall the jackshaft with the small gear already installed? If so, did you rotate the jackshaft as you pushed it into place and then tightened the retaining plate?
jackshaft.jpg

JackGaly.jpg

If you didn't rotate the jackshaft when installing it the two gears may have jammed and been damaged.
I suggest that you remove the intermediate shaft that drives the oil pump and then determine if the gears bind when rotating the jackshaft. There is a plate at the top/rear of the block that retains the small spiral gear.
OilpumpDriveRetainer.jpg

I think you can remove the plate and then extract the intermediate shaft without removing the oil pump from below.
OilPumpShaft.jpg

The bearings for the jackshaft are pressed into the block. I think they are the same as the camshaft bearings in the OHV engine. I had a very small piece of my rear cassette near the rear jackshaft sprocket that could have gotten into the gears.
 






Thanks, 'rod, for the prompt response--you led me in the right direction.

I also remember and earlier post (yours?) where someone noticed problems after installing the half-moon retainer plate for the front of the jackshaft.

I installed the half-moon retainer plate, small gear (to drive the left camshaft chain) and front jackshaft sprocket, and all is well--turns like butter. I'm sure now that I was evaluating this with the jackshaft too far "in"to the block, causing the binding.

I had tried to remove the engaging oil drive shaft, but (fortunately, now) did not succeed. The bolt holding the cover plate to the top of the block busted (despite lots of PB-B and map torch and slow, even torque), which is no big deal, but after cleaning out the well and exposing the circlip, I could not figure out how to pry that circlip out (not enough clearance to the side of the well). While I could probably have beaten it out, I an not certain I'd have gotten one back in if and when I did so. Anyway, I'll jbweld the cap back on and be done with it. All is well!
 



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Thanks, 'rod, for the prompt response--you led me in the right direction.

I also remember and earlier post (yours?) where someone noticed problems after installing the half-moon retainer plate for the front of the jackshaft.

I installed the half-moon retainer plate, small gear (to drive the left camshaft chain) and front jackshaft sprocket, and all is well--turns like butter. I'm sure now that I was evaluating this with the jackshaft too far "in"to the block, causing the binding.

I had tried to remove the engaging oil drive shaft, but (fortunately, now) did not succeed. The bolt holding the cover plate to the top of the block busted (despite lots of PB-B and map torch and slow, even torque), which is no big deal, but after cleaning out the well and exposing the circlip, I could not figure out how to pry that circlip out (not enough clearance to the side of the well). While I could probably have beaten it out, I an not certain I'd have gotten one back in if and when I did so. Anyway, I'll jbweld the cap back on and be done with it. All is well!
I don't remember there being a circlip being on the intermediate shaft. Anyways getting parts for this is such a pain i need to find the part number for the two bolts on the lower cradle that have the washers along with the rear pivot bushing for the timing cassette...pictures for your time.

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