Viton valve stem seals

[itb242]

Does anyone know of a source for Viton valve stem seals. I need at least one set, eight (8) total. The SOHC valve stem dia. is @ 8mm. Bildon Racing used to sell them and Enginetech isn't responding to my email.

David

[Hank Scorpio]

Hi David, my machine shop used Viton seals on my head. I'll see if I can find out some more info for you.

he felt they were the only thing that would take heat of a turbo set up on the exhaust and not completely dry out.

[iadr]

Umm, 8?

You know Volvo only do 4, right?

[Hank Scorpio]

Umm, 8?

You know Volvo only do 4, right?

Yep.

My shop wanted to come up with something on the exhaust side as well, he said he used viton (iirc) seals. We were both worried about the temps destroying them, but these seem to be holding up just fine.

[turbotore]

anybody know of a 16v valve stem seals? (viton)

(7mm shaft valve dia)

[Anonymous]

try Ford 4.6/5.4L V8. They've had their issues as a motor family, but valve seal is pretty good, and they use 7 mm v.stems, and if the stock ones aren't enough, they have an aftermarket.

[Captain Bondo]

What is the theory behind doing the exhaust side? If your exhaust guides are seeing negative pressure you have a problem imo. :wink:

[Anonymous]

anybody know the O.D on ford 4.6&5.8L valve guides

[Anonymous]

(valve seal area)

[itb242]

Umm, 8?

You know Volvo only do 4, right?

Do you know that the commonly available aftermarket silicon-bronze valve guides are machined to accept a valve stem seal on the exhaust side? That means I will need eight (8) valve stem seals.

David

[Anonymous]

The Volvo aftermarket web-based parts suppliers all sell stem seals for 8V and 16V motors, at around $1 each. My last set were brown, not Viton brand (green) but they seem to do the same job. If you're all thumbs like me, buy a few spares to practice on. I found I needed to gently use two tire levers with cloth protection to the alloy head to prise the old seals off the valve stems, then a neat fitting long socket (about 10mm) to drive the new ones on. Make sure you don't dislodge the tiny spring around the seal.
Dick Prince Ovlov.net

[Anonymous]

the Elring valve stem seals.--p/n 348.295--[volvo p/n 1306630-3] are made from FPM...also known as "fluor rubber" or "fluor caoutchouc". This "FPM" is a fluorocarbon elastomer [or fluoro elastomer]; which is what "viton" is. In european references, FPM, fluor rubber, and fluor caoutchouc are used synonymously with "viton"; a trademark name of Dupont.

there are four families of "viton" elastomers; which one a particular valve seal is made from is that manufacturer's choice. Some of the 'viton' formulations are better with the newer motor oils than others.

Unless you were to find a supplier of valve stem seals that specified precisely which viton formulation they used for their valve stem seals, and then received seals made from the latest formulation of viton, I have doubts that buying "viton" seals per se would be any better than the FPM valve stem seals from Elring.

[The color of the material may be a proprietary thing, or a marketing ploy. Some listings for hoses and such made of "viton" that I have run across are listed as being black in color. The Elring FPM valve stem seals I recently installed on a 530 head were black.]

But that choice is yours.

I would tend to agree with Cappy's curiosity re why eight stem seals. Is there some reason a silicon-bronze guide "has" to have a seal? The SOHC head is configured to keep the oil away from the stems and guides; with stem seals being needed on the intakes only because of their constant exposure to less than atmospheric pressures at the other end of the guide.

But that is also your choice.

[turbotore]

cool my spanking new b204ft/gt head(never mounted,used etc)

has bright green seals

gotta dig that :-D

[itb242]

...I would tend to agree with Cappy's curiosity re why eight stem seals. Is there some reason a silicon-bronze guide "has" to have a seal? The SOHC head is configured to keep the oil away from the stems and guides; with stem seals being needed on the intakes only because of their constant exposure to less than atmospheric pressures at the other end of the guide.

But that is also your choice.

Thanks for the information on the Elring valve stem seals. I wasn't aware that they were Viton. My main concern is the valve stem seals survivability at higher temperatures.

The silicon-bronze exhaust valve guide doesn't require a seal, but the readily available ones are machined to accept a seal. I could stick with the stock setup and only use the seals on the intake side. I'll have to look into this more.

The use of the valve stem seal could be benefitical for my application. My engine will be seeing a lot of higher RPM use. Using a valve stem seal on the exhaust side should keep the pressue around the camshaft lower and reduce oil loss through the cam cover breather (early model B21 cam cover). A friend's ITB spec B21 blew a lot of oil through the cam cover breather.

The other side of the coin is that the pressure from the exhaust side may assist in lubricating the exhaust valve spring and bucket. I wouldn't want to loose a spring due to poor lubrication based on an aftermarket design.

Anymore thoughts?

David

[Anonymous]

I can understand how higher RPMs could increase the volume of crankcase pressure, the amount of oil going down past the tappets, and the increase of oil coming out the cam cover vent.

I have found that utilizing both the block mounted crankcase vent [the plastic saparator] and a cam cover vent for crankcase pressures helps reduce the amount of oil that escapes through the venting hoses. And that such a setup also reduces oil loss past the shaft seals.

Using such a dual vent really helped out on both some boosted motors as well as a very tired NA motor. On all of them, the oil leaks disappeared; and on the boosted motors the amount of oil getting pumped into the intercoolers dropped majorly.

I would agree that not using a viton seal on the exhausts may have a benefit as you suggested. My choice would be to not stem seal the exhausts. I like the fact that the stock configuration does not stem seal the exhausts. Letting oil get to the exhaust valve stem and the guide does help cool them, however little that might actually be....but every little bit helps. And any further spray action to splash oil on the springs is good as well.

I think the problem is more of crankcase vent system size.

If I may, I would suggest the following:

...if possible, use a block mounted separator in conjunction with the cam cover vent. Your engine block may not be set up for that if it is a pre-83(?) block. Perhaps there is a way to retrofit one; if the ITB rules allow it.

...enlarge the size of the cam cover vent, if the rules do not permit the block separator. If you are running a single flame trap setup, dual flametraps/hoses would allow more venting. But that would also be subject to the rules.

I am fairly convinced that increasing the size of the crankcase vent system really helps to reduce oil leaks and the amount of oil pumped out through the vent system. And that venting via the block separator and via the cam cover together is the way to go: the block vent handles the ring blowby; and the cam cover vent helps in that; and handles the valve stem blowby--however little or much there may actually be.

Be it from boost or from high RPMs, I think that the stock size of the crankcase vent system is not large enough to handle the volume of the blowby that results from more boost or higher RPMs. Increasing the size of the vent system will help keep the crankcase in negative pressure; which is where I like it to be.

[itb242]

I can understand how higher RPMs could increase the volume of crankcase pressure, the amount of oil going down past the tappets, and the increase of oil coming out the cam cover vent.

I have found that utilizing both the block mounted crankcase vent [the plastic saparator] and a cam cover vent for crankcase pressures helps reduce the amount of oil that escapes through the venting hoses. And that such a setup also reduces oil loss past the shaft seals.

Using such a dual vent really helped out on both some boosted motors as well as a very tired NA motor. On all of them, the oil leaks disappeared; and on the boosted motors the amount of oil getting pumped into the intercoolers dropped majorly.

I would agree that not using a viton seal on the exhausts may have a benefit as you suggested. My choice would be to not stem seal the exhausts. I like the fact that the stock configuration does not stem seal the exhausts. Letting oil get to the exhaust valve stem and the guide does help cool them, however little that might actually be....but every little bit helps. And any further spray action to splash oil on the springs is good as well.

I think the problem is more of crankcase vent system size.

If I may, I would suggest the following:

...if possible, use a block mounted separator in conjunction with the cam cover vent. Your engine block may not be set up for that if it is a pre-83(?) block. Perhaps there is a way to retrofit one; if the ITB rules allow it.

...enlarge the size of the cam cover vent, if the rules do not permit the block separator. If you are running a single flame trap setup, dual flametraps/hoses would allow more venting. But that would also be subject to the rules.

I am fairly convinced that increasing the size of the crankcase vent system really helps to reduce oil leaks and the amount of oil pumped out through the vent system. And that venting via the block separator and via the cam cover together is the way to go: the block vent handles the ring blowby; and the cam cover vent helps in that; and handles the valve stem blowby--however little or much there may actually be.

Be it from boost or from high RPMs, I think that the stock size of the crankcase vent system is not large enough to handle the volume of the blowby that results from more boost or higher RPMs. Increasing the size of the vent system will help keep the crankcase in negative pressure; which is where I like it to be.

I thought about using a dual vent as you mentioned above. My dilemma is that I must use a B21 block. To my knowledge the crankcase breather setup wasn't used on the B21 block. I will have to look into retro fitting this one.

Now that we are on the crancase breather, have you looked into the later sytle vs. the earlier style? Is there a significant difference between the two? The reason I ask is that I primarily play with early B21's.

Keeping a vacuum on the crankcrase helps in reducing windage losses along with reducing ring flutter. I will be using lower tension pistons rings which will be more sensitive to crankcase pressures.

I am planning on routing the breather hoses to a sealed tank and running a piece of tubing to the bottom of the engine compartment to assist in creating a vacuum. I need to find a loophole for this modification.

Good discussion.

David

[dl242gt]

Hello,
The 81 and 82 model B21F engines in the US have the breather box on the side of the block. They are the first years of this and because of this the valve cover no longer is vented. You can use these year blocks with
1980 and older valve cover for more crankcase venting. I plan on adding this to my turbo to reduce the oil venting into the breather system.
Best regards,

[itb242]

Hello,
The 81 and 82 model B21F engines in the US have the breather box on the side of the block. They are the first years of this and because of this the valve cover no longer is vented. You can use these year blocks with
1980 and older valve cover for more crankcase venting. I plan on adding this to my turbo to reduce the oil venting into the breather system.
Best regards,

Thanks for the info Dave. I'll have to look for a later B21 block. I only have '80 B21's around.

David

[Anonymous]

Dave, I know what you are planning: I considered going with the old style cam cover w/ vent on my '83 21FTi. I chose to add a vent instead to the tall '83 cover.

I put a pic up at:

www.pbase.com/image/26786234

...to show you what I did. I figured it would look neater than having a big "U" at the old style cam cover vent outlet to get back over to the right side to go to the turbo inlet elbow.

David,

if you can't come up with a later B21F block, there is a way to add a block vent to the system...

...drill the cover/bracket piece that sits over the oil pump drive gear and supports the air valve/fuel distributor for the Kjet. install a fitting; plumb a hose up to the flame trap area and tee it in, or run it over to the air cleaner;

...drill a hole in the fuel pump cover on the block near the distributor and do the same.

Either way, you have added a block vent to the system.

Going to a catch can makes sense: you remove the possibility of octane killing oil vapor contamination of the incoming air....that makes sense.

But going from the catch can to a road draft tube is less than optimal: you are venting to atmospheric pressure.

If I may, I would suggest this:

...do the catch can setup from both a block vent and the cam cover vent. Then run the hose from that to a pulse-air check valve; which is plumbed into the exhaust pipe past the collector. Then you are feeding into less than atmospheric--the pitot tube venturi effect [I may be mangling my Physics terminology there; but you know what I mean]. The pulse-air check valve will use the negative pressure pulses in the exhaust to extract the crankcase blowby. And you will really have some negative pressure in the crankcase.

[itb242]

Going to a catch can makes sense: you remove the possibility of octane killing oil vapor contamination of the incoming air....that makes sense.

But going from the catch can to a road draft tube is less than optimal: you are venting to atmospheric pressure.

If I may, I would suggest this:

...do the catch can setup from both a block vent and the cam cover vent. Then run the hose from that to a pulse-air check valve; which is plumbed into the exhaust pipe past the collector. Then you are feeding into less than atmospheric--the pitot tube venturi effect [I may be mangling my Physics terminology there; but you know what I mean]. The pulse-air check valve will use the negative pressure pulses in the exhaust to extract the crankcase blowby. And you will really have some negative pressure in the crankcase.

I am going to have to be creative on "exhaust is free" to use what you mention. I have thought about a similar setup, toying with which one will be more acceptable to the tech inspectors at IT races.

Glad we had this discussion.

David

[iadr]

BTW, I did just see http://www.cometic.com/Auto/autopdf/seals.pdf

while looking for something else

[Captain Bondo]

We just had this discussion at work- I was planning on using an early VC breather and then realized that the 531 head I'm hoping to use won't accept one- The dual vent setup seems like a great idea. Pretty minor to just put a fitting in any valve cover really.

Sorry to be slightly ot, but does anyone here have a source for bronze valve guides?

[dl242gt]

Dave, I know what you are planning: I considered going with the old style cam cover w/ vent on my '83 21FTi. I chose to add a vent instead to the tall '83 cover.

I put a pic up at:

www.pbase.com/image/26786234

...to show you what I did. I figured it would look neater than having a big "U" at the old style cam cover vent outlet to get back over to the right side to go to the turbo inlet elbow.

David,

if you can't come up with a later B21F block, there is a way to add a block vent to the system...

...drill the cover/bracket piece that sits over the oil pump drive gear and supports the air valve/fuel distributor for the Kjet. install a fitting; plumb a hose up to the flame trap area and tee it in, or run it over to the air cleaner;

...drill a hole in the fuel pump cover on the block near the distributor and do the same.

Either way, you have added a block vent to the system.

Going to a catch can makes sense: you remove the possibility of octane killing oil vapor contamination of the incoming air....that makes sense.

But going from the catch can to a road draft tube is less than optimal: you are venting to atmospheric pressure.

If I may, I would suggest this:

...do the catch can setup from both a block vent and the cam cover vent. Then run the hose from that to a pulse-air check valve; which is plumbed into the exhaust pipe past the collector. Then you are feeding into less than atmospheric--the pitot tube venturi effect [I may be mangling my Physics terminology there; but you know what I mean]. The pulse-air check valve will use the negative pressure pulses in the exhaust to extract the crankcase blowby. And you will really have some negative pressure in the crankcase.


Thank you! I will do as you are suggesting because the other issue is that the vent is aimed right at the fuel lines which run past that front part of the valve cover. Also thank you for the suggestions on extra or alternate
venting locations!


Another suggestion for good crankcase ventilation is to run the venting to the catch can. Use a sealed catch can and run the outlet hose to the same intake elbow that the stock setup uses. This would technically be legal in my area since you are required to burn the crankcase ventilation
gases in my state. The can would catch the liquid crap and burn only the vapors. It does put the oil vapors in there but it's still much better than having the motor ingest that liquid brown crap to burn.

Best regards,

[itb242]

We just had this discussion at work- I was planning on using an early VC breather and then realized that the 531 head I'm hoping to use won't accept one- The dual vent setup seems like a great idea. Pretty minor to just put a fitting in any valve cover really.

Sorry to be slightly ot, but does anyone here have a source for bronze valve guides?

Not having seen a 531 head, why won't it "accept" one?

David

[benboy]

this is a little OT, but I'm thinking about building up a Canadian version (ie. FIA) IP2 242 in couple of years and am wondering about your rules for induction: You have to use K-jet, correct? My FIA rule book is old and a little vague on the subject, but I imagine our rules are the same. thanks

[dl242gt]

[quote:d4c6e1f29b="Green Death"]We just had this discussion at work- I was planning on using an early VC breather and then realized that the 531 head I'm hoping to use won't accept one- The dual vent setup seems like a great idea. Pretty minor to just put a fitting in any valve cover really.

Sorry to be slightly ot, but does anyone here have a source for bronze valve guides?

Not having seen a 531 head, why won't it "accept" one?

David[/quote:d4c6e1f29b]

Hi David,
The early valve cover with the breather built in is flat at the rear. The valve cover for a 531 head is the same as a 530 or what is on a B230F or FT. So the rear of the valve cover is rounded to cover the different shape.
That is why the early valve cover won't fit on there. You can drill a hole an put your own breather on there very easily.
Best regards,

[fidel]

if you want to have a vent on the valve cover why not just use a filer cap of a B20 it is the same as a B21-23 but has a breather built in to the top. it would save alot of trobble of having to drill and tap a hole in the valve cover or take it off and replace it with an early valve cover.

if you want to keep oil out of your intake, but want to keep negitive crank case pressure, and keep it legal, check these systems out.

http://www.parker.com/racor/ccv_intro.html

http://www.angelfire.com/space/neon/catchcan.html

http://srt4.thebatanesislands.com/mysrt4/gal_20bux_catch_can_060203.html

[towerymt]

The old style valve cover might fit if a different rear cam cap was used. The curved part at the back of the 530/531 valve cover actually seals against the rear cam cap. I think if that were changed, and a plug was custom made to fit the half-moon gap in the head, then maybe it could work. The half-moon plug for the old heads is too narrow I believe. I have most of the parts to try it, but I haven't fully tested it.

PS: I decided to use a 398 head so I wouldn't have to worry about any of these issues, plus I won't have the big plug in the back of the head that likes to pop out at the wrong time and dump oil everywhere.

I may also use a B18 oil cap because I have one, but I think the valve cover breather will be enough.