SBC valve stem seals and spring compressor - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 12-14-2010, 08:58 AM
Registered User
 
Last photo:
Join Date: Apr 2010
Location: Poway, California
Age: 33
Posts: 30
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
SBC valve stem seals and spring compressor

I have put about 75 miles on the SBC 350 that I rebuilt. I have noticed a bit of blue smoke on startup and suspect that it is the teflon comp cams positive stop valve seals that I installed. I am planning on removing these and replacing them with the viton positive stop seals instead. I have also read quite a few threads that have mentioned using the positive stop seals on the intake valves and umbrella seals on the exhaust valves. Is there any particular reason why you shouldn't run the viton positive stop seals on all valves?

When I originally installed the valve springs I used a rented compressor from Autozone which was a piece of junk and very frustrating. I have been looking at this type of compressor manley spring compressor and am wondering if it will work for occasional use. Does this tool provide enough leverage to easily compress the spring?

Thanks

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 12-14-2010, 11:17 AM
Registered User
 
Join Date: Dec 2010
Location: Montrose, CO
Posts: 35
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
I use that type of spring compressor and it works better than those ones that try and clamp the spring itself to compress. I had horrible luck with a "Blueprint TBI" 383 engine i purchased with the same smoking issues. They used World Product Sportsman II heads and from the factory the valve guides were way loose and it used about a quart of oil every 400 miles and was fouling plugs. They wouldn't warranty it saying that there were no defective parts. Anyways I purchased Trick Flow heads and had no further problems and i think you are fine running Vitons on both intake and exhaust, I did and never regretted it.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 12-14-2010, 12:17 PM
Registered User
 
Last photo:
Join Date: Apr 2010
Location: Poway, California
Age: 33
Posts: 30
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks for the reply.

What is interesting is those are the same heads that I am using. I picked them up used and they had just had a 3 angle valve completed on them. Hopefully new seals take care of my problem as I and my wallet would hate to have to replace the heads.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 12-14-2010, 12:47 PM
DoubleVision's Avatar
Not Considered a Senior Member
 
Last photo:
Join Date: Oct 2002
Location: Heart Of Dixie
Age: 40
Posts: 10,657
Wiki Edits: 0

Thanks: 15
Thanked 59 Times in 56 Posts
If you use the rope trick in the cylinders when you do this you can pop the spring and let the valve fall slightly down and shake it, if you feel excessive play no seal is going to stop the smoking. However, another thing that`s worth mentioning here is are you positive the intake sealed? If you can pull the carb and see oil in the plenum the intake didn`t seal. What intake gaskets did you use?
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 12-14-2010, 01:18 PM
Registered User
 
Join Date: Dec 2010
Location: Montrose, CO
Posts: 35
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Double Vision is right on the money if you can feel play and the clearance on the guides is really more than .004 it is going to suck oil in regardless of the seal you use which is what happened to my heads. I was not aware that you should always have new heads gone through by a machine shop because they all say the quality control is not that good and naturally they would error on the side of using/burning more oil than a tight set up where something is going to seize up. Also if the block has been milled/decked the heads are likely to not seal up if they haven't been machined as well.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 12-14-2010, 01:46 PM
Registered User
 
Last photo:
Join Date: Apr 2010
Location: Poway, California
Age: 33
Posts: 30
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I am pretty confident that the intake manifold is sealed up but it is definitely worth checking before I start messing with the valves. I used some Edelbrock intake gaskets with high temp black RTV on the ends. The block was milled slightly to zero deck the flat top pistons but the clearances seemed to be very consistent when I set the intake in place prior to final installation. Thanks for all of the input.

Any pros and cons to having bronze valve guide sleeves installed if excessive guide clearances are indeed the problem?
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 12-14-2010, 06:18 PM
DoubleVision's Avatar
Not Considered a Senior Member
 
Last photo:
Join Date: Oct 2002
Location: Heart Of Dixie
Age: 40
Posts: 10,657
Wiki Edits: 0

Thanks: 15
Thanked 59 Times in 56 Posts
In the past, I had bronze guides installed. This was way back in 1996. Anyways, I didn`t get 20,000 miles out of them and they were shot which really ticked me off. Instead of having them reinstalled I used cast iron guides this go round. I put many a mile on those heads, likely over 50,000 and when I sold them the guides were still in good shape. I`ve had others tell me they`ve had good luck and long use out of bronze guides, I never did so I`ve stayed away from them. When the bronze guides were removed, we noticed the ones with the most wear were worn crooked. They were fine at the top but worn to one side on the bottom which made me think it likely had some valve train geometry issues or the guides weren`t installed straight by the first machinist.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 12-14-2010, 07:56 PM
BOBCRMAN@aol.com's Avatar
Member
 
Last photo:
Join Date: May 2002
Location: Holly, michigan
Posts: 8,129
Wiki Edits: 0

Thanks: 25
Thanked 267 Times in 250 Posts
Teflon "white" seals are often the cause of excessive oil use in SBC. Usually the installer trys to install them cold and damages the sealing surfaces..

If you use the "Blue" Fel-Pro type positive intake seal. You will get better oil controll.

I tend to use a good "umbrella" seal on the exhaust side. Remember there is negative pressure on intake and positive pressure on exhaust. The exhaust can use a little more oil flow and won't run down stems/guide while running.

As for bronze liners. PROPERLY INSTALLED they are the best economical repair. Will last three times as long as iron and can be run tighter clearances.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 12-15-2010, 06:33 AM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
Regarding bronze liners, I've found that setting the geometry up spot-on to be essential for good durability from them. This should be done anyway, but seems to be especially critical when using liners.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 12-15-2010, 02:33 PM
Silverback's Avatar
Boost Retard
 
Last photo:
Join Date: Mar 2007
Location: DC Metro
Posts: 375
Wiki Edits: 0

Thanks: 1
Thanked 2 Times in 2 Posts
The answer about pressure vs vacuum is the deal with using umbrella seals.

Usually, iron heads do better with iron guides, aluminum do better with bronze because of their different expansion rates...
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 12-15-2010, 05:33 PM
Registered User
 
Last photo:
Join Date: May 2008
Location: ohio
Posts: 1,451
Wiki Edits: 0

Thanks: 30
Thanked 42 Times in 39 Posts
Well to let you know your not alone. I built a brand new everything 350 sbc roller motor last year and I used world product sportsman 2's and from day one the problems would just get worse over time. I kept getting oil on my plug threads and after about two months between carb issues and the stupid heads I would have to change plugs.

I kept having miss fire problems with engine and kept checking everything and just could not find out what would cause it. Eventually it got so bad my engine would not idle very well anymore.

Anyways long story short world products uses umbrella seals on there dual spring setup heads and that is a no no with dual springs. I took the heads off and had them checked by the machine shop and I only had less then 3000 miles on my heads and the clearances was horrible on the guides and all my intake valves was just full of oil and carbon deposits.

I had all new bronze liners put in to get everything in spec and I also had the heads done up with a port job and valve job and I had them machined for viton positive stop seals. 600 bucks later they are way better then when I got them new. I will never buy a brand new set of world heads again. They are nice in themselves if everything is up to spec and better valve seals. Umbrella are about worthless to me in my opinion.

There tolerances are horrible and they don't put care into there heads like some others do. A lesson I learned when getting new heads take apart if fully assembled and check everything.

I almost lost my engine cause of carbon getting into the piston rings and I have a few scars in my cylinder walls because of it and am having to rebuild whole engine again just so its all clean. All of this cause of world being cheap on the valve seals and too much guide clearance.
Eric
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
SBC valve seals and retainers jb2wheels Engine 8 06-18-2010 07:38 PM
SBC Comp Cams valve spring, pushrod, break-in questions dlisabeth Engine 2 05-17-2010 06:10 AM
upgrading valve springs and stem seals elcaminodragster Engine 29 08-13-2009 12:04 PM
trying to put on new valve seals SBC 350 Ed ke6bnl Engine 4 09-23-2007 06:52 AM
Chevy 235...valve stem seals? Slickriffs Engine 5 07-14-2004 05:43 AM


All times are GMT -6. The time now is 12:09 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.