How to: SOHC V6 Rear Cassette Replacement

Nope its this one sorry couldnt figure out how to describe it. You can see how the old chain had been slapping against it wearing it down on the bottom in the last pic. I had to back this bolt out to extract the old cassette. Now with the new cassette in If I try to put this bolt back in its pushing on the guide and pinching it.


Also My kit I bought only came with the front chain tensioner for some reason and so I need the rear tensioner. I looked up both pn's you have in your list and both come up on the Tousley website. Both list as tensioners but one is $20 (old pn) and other is $40 (new pn). Was there an issue with old tensioners and reason for me not buying the less expensive tensioner? Sorry for all the questions just already messed up and got a wrong bolt shipped.

deleted

8 mm head bolt

That is one of the two 8 mm head bolts. The head bolts should be installed and torqued to specification before the cassettes. I also ran into problems when installing my new rear cassette. See posts #252 thru 256 of this thread: SOHC V6 Timing Chain Saga

There is a significant difference between the front and rear hydraulic/spring tensioners.

Sometimes the suppliers provide the wrong part. If you receive the wrong one get them to authorize an exchange at their expense. The front tensioner is definitely not suitable installed in the rear position. If you haven't ordered the compression ring I suggest that you do. The hydraulic/spring tensioners are less likely to leak with the compression ring. Make sure you apply some grease to hold the ring in position before tightening or it will drop out of position and not seal.

Also, if that head bolt is going down into a small hole at the bottom, that misshapen end might be the problem.

I'd grind that damaged material off of the end of that head bolt, or use a new bolt. The head bolts are meant for one time use since the 90's, so replace the bolt if you can get it promptly.

Thank you for the reply. This is why im concerned with the two part numbers. Its listed in your parts list as one superseding the other so not sure why the newer pn is twice the price of old one. The tousley said basically no returns but there half the price of my local dealership too so really want to order from them but he told me I have to know the part as he can't tell me what part is what. Luckily I have a complete set of head bolts. Thanks for the heads up on the compression ring I will order that too. So has anyone recently ordered the rear tensioner and can tell me for sure the pn they used? I have a new front tensioner the longer one in your pic. I had debated grinding down the bolt too so might just do that. Thanks again guys

rear tensioner PN

According to my parts list the rear tensioner PN is 7U3Z6K254A
Both Tasca and Tousley: MSRP = $59.78, On line = $39.46

I was afraid you were going to say that lol. Ill order that one then. When I put in the old part # it pulled up a tensioner as well but was only $20. This nickel and dimeing is adding up. Thanks again for the clarification.

Finally off work I can post properly. I checked out the posts the the thread you listed. I have no trouble dropping the cassette in and pulling out as long as that bolt it out but once the cassette is in and I try to install the bolt it starts pushing on the new cassette traction side. I will just grab the new bolt and if for some reason its still hitting it I will grind it down, should fix the issue. The bolt does in fact protrude out a hole in the bottom which is where it interferes with the cassette.

Ok so I ordered the tensioner, upper mounting bolt for the rear guide, and rear jackshaft bolt. Of course I spaced ordering that darn metal o ring. I assume its basically the same as the metal o rings you would use with a common banjo fitting correct only much bigger correct?

compression ring

I suspect it will be difficult to locate an equivalent compression ring - it is very thin but large diameter. The thicker it is the less spring pressure exerted at startup. Also, the oil inlet is close to the face of the hex head.

Many members have installed their tensioners successfully without the compression ring as long as the mating head surface is flat and smooth. It may have to be tightened more than the specified torque to prevent leakage.

Yeah im thinking so too. Checked out the parts store while picking up the front timing cover gasket and nothing even close. Im going to inspect the old rings and assuming no damage I will reuse old ones.

I think mine both came with washers, or I got them with the tensioners. I think you can reuse the old ones if needed, just be sure they are centered in place. You could smear a dab of RTV on them too to help, don't use much at all.

Thanks for the tips. Im guessing only way to get that front tensioner out is to pull off that water inlet which means yet another part I need to buy :-/

Do not touch that water inlet.

That is a can or worms you don't want to deal with.

Leave the entire lower thermostat housing in one piece. The sensors in it will leak if you mess with them. It's almost never necessary to remove the lower housing or sensors. The tensioner should come out and just miss the sensor.

Really?? Hrmmm.. Ok then from my view it looked like a socket would hit sensor right there. Dont have a deep 27mm socket for that so Ill have to go buy one tomorrow and see what happens.

Ok got a deep 27mm. To make sure were on the same page here, dont see how I can get to this darn tensioner out without removing the water inlet :-/. Even if I ground this socket down to where it just reaches the end it still isnt going to work. Am I missing something here?? This is even with this engine out of the vehicle sitting on an engine stand lol.

I used a wrench to loosen mine the first time. But after that I might have been able to get a socket on it. I recall the socket being right against the sensor.

I had to watch the EGR pipe and insulation on the upper intake more than anything. Don't remove that EGR pipe from the intake, take it loose from the other end/valve/bolts.

I unbolted the bracket of that egr pipe which is giving me plenty of room to work there. I didnt have a wrench big enough to fit the tensioner. I tried a crescent but not enough room. I ended up pulling that water housing with the 3 bolts to pull the whole unit off. plenty of room now pulled it out no problem. I noticed the front and rear metal o rings are not that same thickness at least on this engine. The front is paper thin and rear much thicker. I was glad to see the gasket for the water housing is just basically a big rubber o ring so cleaning the mating surfaces was nice and easy.

So another question if you dont mind. Does it matter which cam I time first? I was going to time the rear chain first since the engine is turned with that side up atm. Also I have the otc-6488 kit. How are you guys locking the crank to tighten the crank bolt to spec? The crank holding tool only prevents counter clockwise rotation. Is the cam gear holding tool strong enough to hold it while torqing that bolt?

right cam first

The right camshaft is timed first. See post #5 of the following link for timing the camshafts using the OTC-6488 timing tool kit: SOHC V6 Camshaft Timing

In my opinion crankshaft holding tool 6479 is a rather flimsy tool. I torqued the harmonic balancer retaining bolt to spec with the engine out of the vehicle and holding the flexplate in position with a chain attached to a flexplate bolt at one end and a bolt screwed into the head.

Some members have used a strap wrench attached to the smaller outer diameter of the harmonic balancer.

Good work, taking the whole thermostat assembly off is the last option. Most people have started with the sensors, ,and that got them a leak because they don't come out cleanly(break threads etc).

The TDC tool isn't very strong, it's just for locating TDC(and not good at that IMO).

The jackshaft chain has to be attached and tightened before the cams can be timed. Once the jackshaft is tightened to the crank, you could time either head first or last. They both only attach to the jackshaft, so each is actually timed to the jackshaft. Turn the cams in the normal direction to remove slack in the chains, before finally tightening each cam bolt. If the chains were slack, then the cam timing for that head would be off a bit.