4tec Exhaust Valves: A necessary Replacement?

[ski-d00]

05 timing chains are pretty reliable when compared to later years like 07-11 but have seen them fail but not nearly as many that have dropped valves. I would say the flywheel bolts are less reliable on the 05 than the timing chains. but if you're in there anyway, I'd change them both.

so, four things....and counting.

 

[red2blue]

Anyone got a picture of these "hollow" valves?

 

[Sportster-2001-951C-Stock]

I'm uncertain "hollow" is the best term or if the valve stem is sodium filled even, sounds to me like the head comes off the stem at a welded joint?

 

[Tytan]

72 is the prefix for the bad valves get a good magnifying glass and pull the valve cover to visually check, the number is stamped around the top of the stem right above the keeper.

The 215hp models are the most prone to exhaust valves breaking then the 185hp models then the 155hp models. I replaced them in my RXP this year and might do them in the 05 GTX next year just need to spread the cost out. I have the motor out of the GTX right now doing flywheel bolts which is more time consuming than costly.

I just did the valves and flywheel bolts etc on my RXP and these are the approximate costs off the top of my head for just the valves. Add another $100 for misc stuff if you do the flywheel bolts.
$370. New intake and exhaust valves.
$ 70. New valve seals.
$ 85. New head gasket.
$135. ARP head studs.
$ 36. New rocker shaft bolts.
$696. Total with me doing all the labour.

 

[ski-d00]

The valves are sodium filled which is common practice for high HP high revving engines. The problem is that they rust/deteriorate and it becomes a weak spot in the cored out area, especially in salt water environments and for people who don't winterize.

There are pics of them floating around. They sometimes stretch a little before they break and thin the valve stem out in the bad area. They do look pretty cool when they are all mangled up.

 

[IDoSeaDoo]

That's what I gathered. Also I'm not sure if you can get away with putting more locktite on them, but they say to replace the flywheel bolts as well. In replacing the valves, they say you must replace the rocker arm bolts, but not necessarily the head bolts. So far, I bought the chain (says IWIS on each link), valves (both intake n exhaust for complete peace of mind), complete gasket kit, S/C kit, S/C tools, Klubar grease for reassembly, and will look in the manual and see what it says about the rocker bolts. They say you can reuse had bolts if they're not beyond their length limit, but not the rocker bolts. I will read in the manual about this. I hope to not have to buy them, but will if I absolutely have to. This project is crazy expensive, but I can't think of anything I'd rather buy. I'll have the best boat that money CAN'T buy.

 

[Tytan]

Rocker shaft bolts must be replaced as per the manual. Head bolts can be reused if they have not been stretched too much I did not want to chance it so I went ARP studs which are reusable. For the flywheel bolts you can get an updated bolt kit from Seadoo, part number is 295 501 043 or you can use ARP bolts, part number 134-1002 which are cam retainer bolts for a Chevy LS1 engine that are the correct size.