SoCal.VQ35DE

I've got an 03 VQ35DE engine that burns oil only on startup. Already ran seafoam through it and replaced the PCV valve. Replaced spark plugs, although the oid ones were fine, and not oil soaked. So I'm pretty sure it's just the valve guide seals (opposed to the rings). I plan to do a compression check before I dig into the engine to double-confirm.

That being said, what is involved in changing the valve stem seals? Do I need to pull the head and/or the cams/and timing chain, or can this be done by holding the valves up (at TDC) with compressed air and by getting at them by pulling the valve covers?

I've got the FSM, but it isn't very descriptive as far as what needs to be done before you can replace them.

Thanks!

Jarred@Z1

iTrader: (4)

your defenetly goin to have to pull the heads off which is very complex in the car your better off just pulling the eintire motor and pulling the heads off and sending them to a machine shop.

SoCal.VQ35DE

darn, sucks to be me LOL.

Thanks man.

nismou20

iTrader: (2)

On old school datsuns and Toyotas there was the old rope in the cylinder trick to hold the valves closed while you used a special valve compressor tool to pop the retainers off. Then all you did was pop the old seals off and install new ones. I've even done this on recent DOHC engines in mid 90's engines. There's got to be a way!

johnwigs

http://www.jimwolftechnology.com/wol...MOVER_INST.pdf
this will help you out... still need to pull the timing components... but you dont have to take the engine out or remove the heads

GeturZZZs

iTrader: (2)

im having the same trouble but my motor had 175 across all 6 cylinders in the compression check

johnwigs

replace valve stem seals in 6 hours... start to finish... and that is not rushing it

redlinedifterzx

does this mean ur good im going to do a compression check tomorrow if it passes and the plugs pass would i have to replace those seals to??

johnwigs

compresion check dosent tell you anything about your oil consumption

swwriter

JohnWigs,
The Jim Wolf Spring Compressor you have shown in your post looks like it'll remove the springs OK. Have you replaced the oil seals below? My 350Z is in desperate need of a valve seal replacement and this tool looks very promising.

In reading the 350Z service manual, it says to remove the head, heat it in oil and remove/replace the seals. Can the seals be replaced without bathing the head in hot oil and are any other special tools needed to get the seals out and put the new ones back in?

The local dealership won't touch the seal replacement - the only option they have offered is to swap the engine for a new one...

Thanks in advance for any help you can give me - Lyndon

bryan@Z1

iTrader: (23)

Not sure what the oil bath procedure in the FSM has to do with anything.

You can change the seals with the heads on the engine, it will require pumping up the cylinders with compressed air and using the JWT tool or something similar to compress the spring. Once the spring is compressed remove the valve locks and release tension on the JWT tool. Remove the spring, remove the seal, replace with new seal, reinstall spring, compress with the tool, reinstall locks. Remove the tool, verify that the locks are properly seated and then release the air pressure. Repeat 23 more times.

Jeff92se

iTrader: (4)

6 hours? Can the cams stay in??

johnwigs

cams need to be removed... sit on top of buckets... the heat up the head in oil is to replace the valve guides... not the seals... the seals sit on top of the guides... buy a stem seal puller and just grab around the seal... twist and pull... one at a time... I can do it in 6 hours cause I know exactly how to get out each bolt... remove fan shroud and engine accessories remove bolts (22) on front cover (2) in the upper oil pan, dont need to pull IVT cover
pull front cover... pull timing components... pull tower brace... intake upper and lower plenum
remove harness... take bolt out that holds big plastic piece behind head #1 (easiest to get with long extension from bottom) take rocker covers off pull cams then remove the bucket, spring, retainers, replace the seals 1 at a time...

swwriter

JohnWigs and Brian,

Thanks for your input. Since my post I re-read the FSM and could not find the bit about soaking in hot oil again. I think JohnWigs spotted it with respect to the valve guides and not the seals.
I have another question related to the FSM - do I need to use the special tools for pulling the old seals and re-seating the new ones? I cannot find the specified seal puller, so was going to use a generic one.
I have found the installer tool (drift tool) but it's $145. If I need it I'll buy it, but I've been down that road before - spending a lot of money when a generic product would suffice.

BTW - I ordered the JWT spring compressor, it should be here next week.

thanks again - Lyndon

johnwigs

there is a plier that it is hard to describe... it is bent 90degrees at the handle and the teeth have like a hole in the middle so that it can grip all the way (or at least almost) around the seal... im not sure the part #... it was handed down to me but it works great... when your in there you will see... kind of like hog ring pliers... Im not sure if those will work but they might work... I have all my tools at work so I can't take a picture of it

Edit: I found the snap on part#612EP 90degree pistol grip pliers... carful of the bucket bore!!!

swwriter

JohnWigs - thanks for the Snap-on part number - very handy considering I work for them. Just found it in the associate's catalog and its on order.

Do I need the drift tool to put the new seals in?

johnwigs

I use 10mm socket and extension!!!... got to be careful dont get too cowboy with it

10-E-C-350Z

iTrader: (9)

Any updates? Just fired up my car after a deployment only to find nice little plumes of blue smoke coming from the d/s bank. I fear it may be these suckers.

winchman

Looks to me like replacing the stem seals might be quite different from replacing the valve springs. That's a deep hole to work in, especially with the valve stem in the way.

How are the valve seals held in place?

bryan@Z1

iTrader: (23)

Nothing really holds them, they just pop into position. You'll need a long slim pair of needle nose pliers or a valve seal puller to get them out but it can be done.