Toed

Hello all, I just recently purchased a 2003 350 its a very beautiful car and i already love it so much. The only problem is, its not running just yet because the valve seals need to be replaced, normally id say something like this is no problem for me and honestly if i knew where to start i would. but im not entirly sure what i should be doing and how to go about fixing it up. Any video suggestions or tips or just about any info on what i should do would be greatly apreaciated. Please and Thank you. much love to all

dkmura

iTrader: (64)

Welcome and your question only begs more questions. First, what kind of wrenching skills do you have? Ever tried rebuilding an engine before? Do you have a garage or indoor spot to work on this project as the seasons change? What about tools?

Maybe a few more details about this Z itself would help. Miles? Model type (base, enthusiast, performance, touring or track)? What did the previous owner tell you about it? Usually, worn valve seals would not stop a VQ35DE from running. Without more information, it's unlikely to gain any useful advice on how to repair your recently purchased Z (hoping you didn't pay much).

Toed

well, ill be honest. its my first car as well as my first time working on a car. im not sure what all tools ill need, but i do have a wrench set and a torque wrench aswell as a jack and stands. I dont have a garage or space indoor to work on it but i do have a full carport to myself. the most the owner told me was that the valve seals need to be replaced, and that it was smoking when he bought it and brought it home, and that he would fix it himself he just didnt have time with work and kids and all of life and what not. I only paid $1500 for it. the model is a base im pretty sure and it has 146K miles.

Heel Til I Die

iTrader: (2)

Oh dear...

icer5160

iTrader: (4)

Hi Toed,

I think you can replace the valve stem seals without removing the heads from the engine. But you need a special tool to remove the valve springs and spring buckets to gain access to the seals. I think it would also be wise to hook up some compressed air to the spark plug hole to keep the valves from dropping into the combustion chamber.

But to be honest, this is major surgery for a VQ35DE. You would need to remove the upper/lower plenum, valve covers & camshafts, which will require you to also remove the timing set. This is not something you're going to be able to complete in a carport over a weekend with basic tools. These are very sensitive engine parts/components that need special care/attention. I would highly recommend taking the Z to a pro for their opinion/diagnosis before taking any action. Another option is to swap the engine with a lower mileage, used, long block (also not going to be something you do easily in a carport). I have over 10 years of ownership/experience wrenching on 06 (RevUp) 350Zs, and a timing chain/valve seal job is something I would be worried about tackling myself. I've done plenty of other items such as exhaust headers, clutch job, wheel bearings, axles, differential, bushings, suspension, brakes, and more. But major engine surgery on these can go south real quick if not done perfectly by the book.

The previous owner could have misdiagnosed the car. Valve stem seal problems are not uncommon for higher mileage Zs that were abused or neglected. But if it's smoking really bad, the root cause could be something far worse. For $1500, I'd say you did alright if the car can move under it's own power and is mostly complete, accident free record, and maybe some cosmetic blemishes. If it's a salvage title and a basket case of cosmetic issues, then I would recommend parting it out and putting that money towards a cleaner 350Z.

Cheers!
-Icer

Toed

So youre saying i shouldnt just freeball it, and take the whole engine out and apart replace the valve seals and put it all back together in my carport with a couple of friends over the next few weeks? cause thats kinda my plan as of now. and honestly in my thinking the worst that can happen is the engine dosent work and i have to buy a new one. Which isnt much of a problem to me because not only will i have a better knowledge on the engine ill know how to fix it and or any other problems the next time something like this comes up. I honestly dont have anything but time right now and expect to have to put a good amount of money into the project, and would really rather do it myself and learn something new than have some professional do it and just loose money when i could gain so much more from getting in there and taking everything apart and putting it back together. I just printed out the "Engine Mechanical" FSM and i think its gonna be a good basis to get something done. if you think this is a bad idea please dont be afraid to tell me, althought i cant say it will stop me unless it is thought that it will not in anyway possibly end well for me.
I also plan to record my journey of tearing down and rebuilding the engine and starting a yt chanel for my car, unless this dosent sound like a good idea.

icer5160

iTrader: (4)

If it was me, I wouldn't attempt it in a carport since you're somewhat exposed to the elements (wind, dirt, dust, rain, moisture, etc) and don't have a workbench, tables, power, etc. at hand. That being said, not all carports are built the same and maybe your situation offers more protection than what I'm used to seeing here in CA. I think the biggest problem you will face is keeping the parts tracked and organized. You will need a safe location to store the parts until you're ready to re-assemble. You may also need special permission from the property manager to work in a carport (assuming apartment or condo complex). Most, if not all apartment/condo complexes around my area strictly prohibit mechanic work in carports or parking lots of the complex. To give you the best access to the front of the engine for the timing chain removal, you will need to drain the coolant, remove the upper radiator hose, and pull out the fan assembly. Not hard to do, but make sure to capture all the coolant and other fluids during the process, otherwise your neighbors or property mgmt are likely to come after you (you be the judge, maybe it's not an issue in St. Louis, but for sure in CA).

I still recommend getting a 2nd opinion from a professional on the state/health of the engine. You're more than welcome to attempt this with your friends, it's your car! But it would really be painful to go through the valve stem seal replacement + timing set replacement + water pump (might as well if you go that far), and many other smaller ticket items that add up, only to discover you have cylinder wall scoring, or toasted piston rings, or worse.

I agree that working on the vehicle yourself is the best way to learn, but usually folks start with entry level maintenance items like brakes and oil changes, and then, after getting more experience, graduate to the more complex stuff. You're jumping straight into engine internals, something that most professional automotive shops don't even touch these days. That takes guts and I respect that. Read through the FSM, watch videos on timing chain jobs, valve cover replacements, etc. Get familiar with the process and tools required. Start researching parts costs and incidentals. I highly recommend sticking with an OEM timing chain set. The Viton valve stem seals are popular replacements, there are aftermarket aluminum valve covers from CZP that I would use (budget allowing).

Now, regarding YT videos on the process. Just realize that filming and editing will add double or triple the amount of time to the project. If you can afford that, go for it.
Cheers!
-Icer