Valve Guides "Q" ('91 Q45)

[Raxephon]

Is there some issue with the valve guides?

I spoke with Atlantic Infiniti a while back.

Got to talking about bad timing guides and it was mentioned that if you bent a valve and tried to have it replaced along with a new guide installed that you wouldn't be able to get the valve guide to seat properly, (ie, it would leak).

I don't have any damage to my motor, but I'm working on a build-up that requires stainless valves and of course new guides to accomodate them.

I searched the achives, recent posts, etc.., but never came up with anything short of "Go Back".

Am I going to run into problems with new valve guides or can I just go by the FSM for removal & replacement without any worries?

Also, I've heard that one of Nissan's newer motors came with titanium valves but never found out which series motor it was.

Is this hearsay or did I overlook a thread on them?

[maxnix]

Do you have an FSM?

I think the OEM exhaust were Na filled stems.

[elwesso]

the VK45 has titanium valves...

[Q451990]

I think the issue was that the head has two or three mating surfaces that have to be correct for the valve to seat properly... not sure how that impacts what you're doing.

Heath

[Raxephon]

Do you have an FSM?

I think the OEM exhaust were Na filled stems.

My bible? Most definately. Yeah, the ones stamped "6U" are the sodium ones.

the VK45 has titanium valves....

Great! Any idea as to whether these are intake, exhaust, or both?Or better yet, which models had this motor?

I think the issue was that the head has two or three mating surfaces that have to be correct for the valve to seat properly... not sure how that impacts what you're doing.Heath

Are you talking about the valve seats or the valve guides?

I thought that the valve stem only makes physical contact with the valve seat and the valve guide(as well as the rollers). Wouldn't those two be the determining factor in seating properly or is there a third that I am overlooking?

[Q451990]

Are you talking about the valve seats or the valve guides?

I thought that the valve stem only makes physical contact with the valve seat and the valve guide(as well as the rollers). Wouldn't those two be the determining factor in seating properly or is there a third that I am overlooking?

Sorry, I was talking about the valve seat... the seat has three angles (which is apparently unusual)... not sure if there's an issue with the guide.

Heath

[Raxephon]

Any notion as to whether or not the VK45DE valve seats are multi-angle, (3 angles), as well?

[Q451990]

From looking at the 2002 Q service manual, I don't think so... can't tell for sure, but I think it's just an angled slope. It shows you how to check the diameter at three different points, but doesn't mention anything about angles.

Intake Valves slope from 1.34" to 1.402-1.409" to 1.575-1.583"Exhaust Valves slope from 1.130" to 1.205-1.213" to 1.370-1.378"

Heath

[Raxephon]

So it was the 2002 Q45 that got the VK45DE?

Guess I'll be looking at getting new seats as well then.

[Q451990]

So it was the 2002 Q45 that got the VK45DE?

Yep.... as well as the First Gen (and current) M45?

Not sure if the seats are compatible. If your foam is in good condition you can have all new leather installed for your existing seats for about $500 (at least here). The First Gen. Q seats have been described as "sitting in the hand of God" so I don't know if a newer seat would really be an improvment.

Heath

[Raxephon]

Yep.... as well as the First Gen (and current) M45?

Not sure if the seats are compatible. If your foam is in good condition you can have all new leather installed for your existing seats for about $500 (at least here). The First Gen. Q seats have been described as "sitting in the hand of God" so I don't know if a newer seat would really be an improvment.

Heath

Damn! I gotta move to South Carolina.Lowest priced upholsterer localally wanted $300 just to do the backseat.

I'm not sure what the '02 Q45 or the M45 interior is like since the closest Infiniti dealer is 2 hours away from me.

But I will say that since I got my Q45, I haven't been comfortable in any other interior.