Need advice with ordering valves and cylinder head gasket

[nonickatall]

Hello, after a lot has happened in my life and I haven't really made any progress with some things, I need to finally finish my engine overhaul.

I discovered some time ago that some of my valves were worn at the top, practically where the rocker arm engages, which obviously isn't ideal.

Old thread

I bought some very good used cylinder heads and had them reconditioned at a professional engine shop.
They pressed in new valve seats and resurfaced the cylinder heads.
They also told me I absolutely had to install new valves because otherwise the new valve seats would wear into the old valves.
According to them, they measured the valve stems and they were fine.
Now I wanted to order valves and a cylinder head gasket set from RockAuto or elsewhere, so I can finally do my engine overhaul.

However I'm having trouble finding the right parts because I saw on RockAuto that they offer valves in different sizes, both in diameter and length.

And I don't know anything about the different valve manufacturers or which ones are recommended.

So I am a bit lost as to exactly which valves I need to order.
Does anyone know anything about this topic and can offer some advice, as well which cylinder head gasket you would recommend?

 

[strutaeng]

Umm, I'm not familiar with the heads portion on these engines, but have taken a few heads to my local machine shop for reconditioning. I once took them some heads from a LQ9 engine I'd bought but had spun a main bearing and catastrophic damage. Those heads the machine shop told me were already worked on and they didn't do a good job. Besides all the bent valves it had, they said it was like $600 to fix those, and could find another set of good, used 317 heads for cheap, which is what I did. $75 for used 317 heads and another $350 for them to refreshen them, and off I went.

Why not let them do the valve ordering for you? They should have the knowledge to get the right parts and will know more about quality parts.

 

[Joseph Garcia]

^^^^^x2^^^^^

Let the shop that did the heads work tell you what the required valve dimensions are, and hopefully give you some specific valve brand/part numbers that meet the specs. Anything else is simply a crap shoot.

 

[nonickatall]

^^^^^x2^^^^^

Let the shop that did the heads work tell you what the required valve dimensions are, and hopefully give you some specific valve brand/part numbers that meet the specs. Anything else is simply a crap shoot.

I guess that's a good idea in the USA, but here in Germany, my car, this engine, is absolut exotic.

I guess my heads were the first LQ heads they ever machined.

And if they are willing to get the parts for me, they buy them at rockauto for 5 dollar per pce and sell it to me for 50 each...

No good idea...

 

[strutaeng]

What year is this vehicle/engine is this BTW? 2006 Escalade? LQ9?

 

[nonickatall]

What year is this vehicle/engine is this BTW? 2006 Escalade? LQ9?

Yes, 2006 LQ9 6 Liter

 

[Joseph Garcia]

I guess that's a good idea in the USA, but here in Germany, my car, this engine, is absolut exotic.

I guess my heads were the first LQ heads they ever machined.

And if they are willing to get the parts for me, they buy them at rockauto for 5 dollar per pce and sell it to me for 50 each...

No good idea...

Well..........

When the machine shop resurfaced your cylinder heads, I assume that they resurfaced your valve seats in the combustion chamber, as well. If I am correct on that, the mechine shop had to have some specific specification, in order to do that valve seat work. You can start there.

 

[strutaeng]

Yes, 2006 LQ9 6 Liter

Ok, I was afraid you were going to say that those engines are not common there...

The valves are different size between the intake and exhaust. That's not what you are talking about, right?

I saw on your other thread someone mentioned you have an LP conversion? I see Rockauato does show another part for LP...

Also, Google says when getting new valve seats, you do not necessarily need new valves: https://www.google.com/search?sca_e...oFHTMWA0gQ0pQJegQICxAB&biw=1920&bih=945&dpr=1

Unless they are bent or damaged beyond their service limit.

If you are replacing all intake and exhaust valves, that's gonna get expensive.

 

[nonickatall]

Ok, I was afraid you were going to say that those engines are not common there...

The valves are different size between the intake and exhaust. That's not what you are talking about, right?

I saw on your other thread someone mentioned you have an LP conversion? I see Rockauato does show another part for LP...

Also, Google says when getting new valve seats, you do not necessarily need new valves: https://www.google.com/search?sca_esv=bcbe1a3c17fe5261&rlz=1C1GCFD_enUS1146US1146&sxsrf=APpeQnt-fr2HP6o3R3tu6zjVxDfl0a3OLw:1784320677761&q=LS+heads+does+valve+seats+require+new+valves&source=lnms&fbs=ABfTbFVQT6KYne3_7HzvYh-3OtGxmA6qToXQOWeUvgXQ5M6Rvtme8by44bKODdrCzbFzI7AsfrEtRBrT48Piu1eppjr9ACTKFabiPnBDTMZqz0tfH_m4-BTqMeWSLGBdprp7deqZgBOdu0_deNzHlf0ZqFnuwSOrYG4OeEJEAFP1B77TN8UxMc_3Wh0h4Og2xtkNYBUFF1dgHvRYxmt0UGEIA7IVxX1sn1ITua4O6NEp3GoXV92PCQ4&sa=X&ved=2ahUKEwjM7KbByNqVAxVQmmoFHTMWA0gQ0pQJegQICxAB&biw=1920&bih=945&dpr=1

Unless they are bent or damaged beyond their service limit.

If you are replacing all intake and exhaust valves, that's gonna get expensive.

No, I'm not talking about the fact that intake and exhaust valves are different sizes, that's obvious.

Rather, as you can see in the two screenshots from RockAuto, the valves are offered with different descriptions. For example, if we look only at the intake valves, it says "dia, stem, head," and the values are all slightly different.

For some, this information isn't even included. So, I'm wondering which valves are right for me?

Do I need to measure them using specific tables, or are the differences so small that they're irrelevant?

Of course, I'd hate to order valves, install them, finish my cylinder heads, complete my engine, and then find out something doesn't fit...

Regarding your link about whether you even need new valves, it also says that if you have new valve seats, you should install new valves.

Sure, 16 valves cost a bit of money, but I love my truck and I want to drive it for the next 20 years.

This car is so practical, so well-built, and so easy to repair. I've spent decades tinkering with German cars, and I can tell you, I can't stand the sight of them anymore.

Everything built since 2000 is so over-engineered and difficult to repair, and often central components like transmissions and engines break down. This doesn't seem to be the case with our trucks.

Sure, things break down there too, but it's mostly normal components that you can consider wear parts, like water pumps, the magnetic clutch of the air conditioning compressor, or the fuel pump.

I love my car, especially because green world-savers always gasp for air when I drive into the supermarket car park and they're standing next to me in their electric cars...

 

[Fless]

It's fairly standard procedure for a machine shop to verify valve sealing when cutting the seats; for this test, at least one cylinder's valves should be used in order to make sure the seat cut (hopefully it's a 3-angle?) matches the grind and diameter of the valve that's going to be used. Usually that's a test for each cylinder, applying vacuum to the intake and exhaust ports as separate tests.

Valve Refacing Guide | Procedures, Tips, Tricks & Why It Matters

Learn automotive valve refacing and reconditioning procedures, practical tips, troubleshooting tricks, and why proper valve work matters for performance, sealing, and engine longevity.

valverefacer.com

I'm not sure how you would know which valves to buy if your machine shop won't tell you. Maybe you could order the valves they specify and have them complete the valve seating and sealing tests so you don't install something that might not work.

 

[nonickatall]

It's fairly standard procedure for a machine shop to verify valve sealing when cutting the seats; for this test, at least one cylinder's valves should be used in order to make sure the seat cut (hopefully it's a 3-angle?) matches the grind and diameter of the valve that's going to be used. Usually that's a test for each cylinder, applying vacuum to the intake and exhaust ports as separate tests.

Valve Refacing Guide | Procedures, Tips, Tricks & Why It Matters

Learn automotive valve refacing and reconditioning procedures, practical tips, troubleshooting tricks, and why proper valve work matters for performance, sealing, and engine longevity.

valverefacer.com

I'm not sure how you would know which valves to buy if your machine shop won't tell you. Maybe you could order the valves they specify and have them complete the valve seating and sealing tests so you don't install something that might not work.

When they did the machining, they asked me for one intake and one exhaust valve they used to measuring.

So I think the machining fits to the original valves..

 

[Fless]

If I were you, then, I'd get some valve lapping compound and do the lapping procedure for each valve. Only then can you know if the valves and the seats match on the contact area. However, you won't know if the valve combustion surface is proud or at proper depth, depending on the application; new seats can complicate that depending on how they were cut. But perhaps it doesn't matter; maybe the machine shop took that all into consideration when they did their work.

Maybe measure your old valves to be able to buy new ones, or just lap the old ones.

One particular YouTube site that I watch occasionally is Jim's Automotive Machine Shop. Some of their videos go through the intricacies of head work and can be very informative.

https://www.youtube.com/@JAMSIONLINE/videos

 

[West 1]

There is a lot more to know when assembling heads. Let a shop assemble the heads. Valve lapping is fine if you have a used engine and just want to make sure the surfaces all mate well. Did you pay for a 3 angle or 5 angle valve job? With new seats installed you want the valves to fit those new seats perfectly. The valve height is critical. Your springs should be tested for tension, new valve stem seals installed. All these things are done for you when you have a valve job done.

You should have asked the shop how much to do a valve job and been done with it. I did both heads on my 6.2L after a valve seat dropped, bent a valve and broke a piston. Both heads fully rebuilt with all new seats and new parts where necessary, surfaced and done. $700 in California where everything costs more.

I am also fully Gold certified ASE for Engine Machining. Along with Engine Performance, Engine Repair ASE certifications. With that said, I let a shop do this type work because they have the tools and knowledge to do this job so it works and lasts.
I know what needs to be done but I don't have the proper tools to do this type work in my garage.

In Machine Shops if they find one bad valve in your engine they will toss it out and use another valve from used good parts they have on hand normally. Same with valve springs, if a couple of yours do not meet specs they grab some from used inventory that test good and you are repaired and ready to go. These parts are either good and meet specs or they are bad and get tossed. I could care less if the valve is used or has 100,000 miles on it as long as it meets testing it is good to go.
If you ask for new valves they are always happy to sell the customer what they ask for. That is normal business.

Many owners have rigs with over 200,000 miles on them and still run them to red line 6,000 RPM when passing a car. The valves don't suddenly fall apart. If they are in spec they work.

 

[nonickatall]

There is a lot more to know when assembling heads. Let a shop assemble the heads. Valve lapping is fine if you have a used engine and just want to make sure the surfaces all mate well. Did you pay for a 3 angle or 5 angle valve job? With new seats installed you want the valves to fit those new seats perfectly. The valve height is critical. Your springs should be tested for tension, new valve stem seals installed. All these things are done for you when you have a valve job done.

You should have asked the shop how much to do a valve job and been done with it. I did both heads on my 6.2L after a valve seat dropped, bent a valve and broke a piston. Both heads fully rebuilt with all new seats and new parts where necessary, surfaced and done. $700 in California where everything costs more.

I am also fully Gold certified ASE for Engine Machining. Along with Engine Performance, Engine Repair ASE certifications. With that said, I let a shop do this type work because they have the tools and knowledge to do this job so it works and lasts.
I know what needs to be done but I don't have the proper tools to do this type work in my garage.

In Machine Shops if they find one bad valve in your engine they will toss it out and use another valve from used good parts they have on hand normally. Same with valve springs, if a couple of yours do not meet specs they grab some from used inventory that test good and you are repaired and ready to go. These parts are either good and meet specs or they are bad and get tossed. I could care less if the valve is used or has 100,000 miles on it as long as it meets testing it is good to go.
If you ask for new valves they are always happy to sell the customer what they ask for. That is normal business.

Many owners have rigs with over 200,000 miles on them and still run them to red line 6,000 RPM when passing a car. The valves don't suddenly fall apart. If they are in spec they work.

$700 for rebuilt cylinder heads, include work and material?! You live in the land of the blessed. I paid €1300 just for new valve seats and a resurfacing, which is pretty much the equivalent in dollars.

I've rebuilt enough cylinder heads and engines already, I have my own workshop, the necessary tools and know-how, and I'm confident in my ability to do the job.

I actually really enjoy it because it's simply fun to work on our cars, unlike the German cars I usually have to work on.

However, I haven't made any progress with this issue because one problem after another keeps cropping up...

 

[West 1]

I just noticed you are doing this in Germany! All rules change as access to parts and good machinist that know the LS engines may not be available. Good luck with your repair.