thas my question...

i have some bent valves. I need to buy the parts to replace them, but i'm a little confused as to what i need

here's what i have so far:

Manly Valves
OEM Headgasket
IM Gasket
ARP Headstuds

if i buy the valves, don;t valve seals come with it? if not do i buy brand new oem valve seals? WIll it be compatible with aftermarket valves?

Whats the purpose of lapping ur valves if u have valve seals? and last but not least how much do valve seals go for?

Thanks

 

When you pull the valve through the valve seal, it's trash. After your valve work and spring height adjustments, install the seals on the guides. Use a high-pressure non-moly grease on the valve tip and stem. Push the stems through the guides and seals and then install the springs/retainers. Never pull a valve back through a new seal, or you'll ruin it. They're one-shot affairs.
The seals control oil flow to the guide and valve stem. They do not seal combustion pressure.
Lapping valves is a good way to cause premature wear on both the face of the valve and the seats in the head. It's not a good practice, unless it's an emergency....like no other way to make it to final round at the track on a big pay-day.

 

I didn't think they were ruined after removing a valve.

But if you're gonna spend the $15 per valve to replace them, why not replace the $1 per valve stems while you're at it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Woofer &raquo;</TD></TR><TR><TD CLASS="quote">When you pull the valve through the valve seal, it's trash. After your valve work and spring height adjustments, install the seals on the guides. Use a high-pressure non-moly grease on the valve tip and stem. Push the stems through the guides and seals and then install the springs/retainers. Never pull a valve back through a new seal, or you'll ruin it. They're one-shot affairs.
The seals control oil flow to the guide and valve stem. They do not seal combustion pressure.
Lapping valves is a good way to cause premature wear on both the face of the valve and the seats in the head. It's not a good practice, unless it's an emergency....like no other way to make it to final round at the track on a big pay-day.</TD></TR></TABLE>

wait so according to what ur telling me, having a machine shop relapp/reseat my valves a big no no?

so techincally all i have to do is pull out the old valve, use ur method of installing a new one in and that's it? it's not necessary for a machine shop to do any work?

if so how come whenever i call for price quote they give me a labor quote and then a machine shop qute afterwards telling me that i need to get my valves reseated?

i'm confused...

by the way, i dont mind spending the etxra money needed to get the job doen right, i just didnt know if it was needed or not

 

yeah i am confused too

 

If the valve seats are in good shape and the faces of the valves are true, everything should go together fine. If you have an issue with the seats or the valves, they should be machined to provide concentric surfaces to seal combustion pressure. Freshly machined seats and valves should NEVER be lapped. Lapping compound embedds itself in the faces of the valves and in the seat inserts. It causes premature errosion of those surfaces during operation of the engine.
Lapping valves was common-place in the 50's and early 60's, but engine builders finally figured out that it was a tempory "fix" at best.
Today, some shops that aren't capable of machining hard seats properly have apparently reverted to the practice...and it's no good..unless you're trying to seal the engine up so you can sell the car in a hurry to some sucker.
I've been doing race heads for a living since the late 60's and I can assure you that I'd also lap valves if it wasn't a detrimental to valve seating performance/life.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Woofer &raquo;</TD></TR><TR><TD CLASS="quote">If the valve seats are in good shape and the faces of the valves are true, everything should go together fine. If you have an issue with the seats or the valves, they should be machined to provide concentric surfaces to seal combustion pressure. Freshly machined seats and valves should NEVER be lapped. Lapping compound embedds itself in the faces of the valves and in the seat inserts. It causes premature errosion of those surfaces during operation of the engine.
Lapping valves was common-place in the 50's and early 60's, but engine builders finally figured out that it was a tempory "fix" at best.
Today, some shops that aren't capable of machining hard seats properly have apparently reverted to the practice...and it's no good..unless you're trying to seal the engine up so you can sell the car in a hurry to some sucker.
I've been doing race heads for a living since the late 60's and I can assure you that I'd also lap valves if it wasn't a detrimental to valve seating performance/life.</TD></TR></TABLE>

thank u for ur explanation but i'm still a lil lost...

so basically lapping valves = temporary band aid

machining valves is the correct way of doing it &lt;----- this is the method u would want to use right? also, does this occur everytime when u replace ur valves or it isn;t necessary at all?

basically what i am tryiong to understand is that every mechanic that i bring my car to they say to reseat the valves alone is gonna cost xxx.xx of dollars that price that they are giving me does not include the labor to take the head off, it also does not include parts...

Thank u for ur help

 

I have pulled all my valves through the seals and put them back in with some oil on the valve. A year later my motor is the cleanest running B-series motor I have ever worked on, does not burn any oil what so ever, no smoke at WOT or in vacuum. I don't agree with u, just cuz I have done that to all 16 of my valves and they are all fine. But for new valves u should buy new seals.

 

I'd certainly recommend machining the valves (if they aren't new) and checking the face run-out on new ones to make sure they weren't dropped and "tweaked" between the manufacturer and you prior to installation. I also recommend machining the seats to net a crisp and true face.
Lapping is a temporary fix at best.
We can't ever assume that a seal's not damaged by repeated installations of valves here and while the cost of Honda's seals is seemingly $$$, new seals are a lot cheaper than the time and expense of pulling the head to replace them porperly...or the cost of repairs from detonation caused from excessive chamber oiling.

 

I disagree w/ your idea that lapping is a temporary fix, but I don't have too much experience to back that up.

 

I argued with my parents for the first half of my life unitl I finally realized that they were just trying to save me from making the mistakes they'd made... they were right all along...............

 

ok dad thanks for the lapping leason good post

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Woofer &raquo;</TD></TR><TR><TD CLASS="quote">I argued with my parents for the first half of my life unitl I finally realized that they were just trying to save me from making the mistakes they'd made... they were right all along...............</TD></TR></TABLE>

great reply