Club Cobra

Club Cobra (http://www.clubcobra.com/forums/)
-   FE TALK (http://www.clubcobra.com/forums/fe-talk/)
-   -   Valve seat in E-brock heads (http://www.clubcobra.com/forums/fe-talk/122717-valve-seat-e-brock-heads.html)

MOTORHEAD 10-08-2013 06:59 AM

Valve seat in E-brock heads
 
Anyone here ever have a valve seat come loose in an edelbrock head ? I think my #6 exh seat is loose, based on noise on that side of the engine after eng is warmed up. Listened to header pipes with stethescope and #6 has randome "clinking and clanking" noise which other cyl's do not.
Will be pulling exhaust later today to get a look.

Jerry Clayton 10-08-2013 07:48 AM

all the engines I've seen that had loose valve seats were ----------------------------

IF--------the valve seat isn't installed with the proper interference fit----AND --------the engine is shut off with the exhaust valve somewhat (only a little bit) open (off the seat) the seat could possibly drop down out of the casting, and would after the engine has cooled off---would cause excessive valve tappet clearance which would then be a noise you could hear-

Suggestion is to remove the valve cover and check valve clearances-if you find excessive clearance then look for the cause-----

Of course, if you are running flat tappets, it could be a lobe wiped out---------

MOTORHEAD 10-08-2013 08:05 AM

Thanks Jerry,
FWIW i'm running hyd roller. This problem seems to have started after I was doing high RPM
(but not over 5k rpm) runs to ck afr while jetting the webers. Although thewater temp never went over 90c, I did experience some afr's of 16:1 +, which may have resulted in high cht's .

Jerry Clayton 10-08-2013 08:34 AM

So you possibly could of shut it down while there was an extremely high temp on that cylinder??? Webers---tune individual cylinder-------------

I'd still check valve lash before you disassemble it---------

CHANMADD 10-08-2013 10:47 AM

5000 rpm is not high revving.......I put my foot down at 5000........

Jerry Clayton 10-08-2013 01:09 PM

exhaust temp will be 1600 +_ with 16-1 afr and the seat could come out of the alum if shutdown with that valve open which will increase the clearance causing clicking---if it is out any appreciably distance the piston will hit the valve and soon the seat and/or vavle will be destroyed followed in short order of the cylinder head and piston-----

At least with Webbers you won't have pieces flowing backwards thru the intake into other cylinders-----------

MOTORHEAD 10-08-2013 06:14 PM

Valve train is all tight (hyd lifters). Plugs on this bank (5-8) are all oil fouled, 1-4 are not. Took headers off to inspect exh valves, could not see seat or valve heads, only end of guide, stem. Chambers coked up too much for 600 mi. #'s 5&6 have a very obvious oil path comming out the port, actually dripping from # 6. Also cold cranking comp test is lower than previous on those two cyl.
Guess I'll pull intake and head.

ERA Chas 10-08-2013 07:34 PM

If it's not the intake gasket pulling oil, it's the stem seals. Remove the Shelby teflons and replace with vitons. Barry R can supply them. The intake gasket should be a 1247-S, also from Barry.

Jerry Clayton 10-08-2013 08:33 PM

You can replace the seals without pulling the head---------------

blykins 10-09-2013 03:59 AM

Yep....

If you need a set of Viton valve seals, I'll send you a set...no charge.

Jerry Clayton 10-09-2013 08:01 AM

Nice Brent-----------Reading this as I have my first coffee of the day--------might be a classic F up---original valves were 3/8 and the Edelbrock are 11/32? the wrong seals could of gotten installed on the head on that side-----about one of the only things that would cause something like that on one side and the other be differant

blykins 10-09-2013 08:02 AM

It's possible, but my money is on a bad intake gasket. :)

Jerry Clayton 10-09-2013 08:52 AM

How much do you wanta bet?????? I'll pick you up and we'll head down there----------after I get another cupajoe

MOTORHEAD 10-09-2013 09:15 AM

Jerry: Coffee's on ! Come on down !!

ERA: was told and shown by eng shop builder the seals are viton.

Jerry: stem measures .370 above keepers/retainer.
My on-the-car spring comp only grabs outer coil, the inner and damper float, doesn't work very well. I could fab a rocker shaft sub and use a lever type I suppose.

blykins 10-09-2013 09:21 AM

I've got an FE-only on-the-head spring compressor that I use for when I break-in and dyno flat tappet stuff. There's a guy on Ebay that sells them....about $75, but they work really slick.

MOTORHEAD 10-09-2013 09:26 AM

The other possibility is a lifter intermittantly collapsing.
The noise is not there when eng is cold, only after up to temp.
The oil in comb chamber is the secondary problem, the source of the noise is the primary concern, and with the possibility of major damage being done if the seat comes out and jams the valve, I feel the only prudent thing to do is tear down the top end.

MOTORHEAD 10-09-2013 09:31 AM

5 Attachment(s)
here's some pics:

MOTORHEAD 10-09-2013 09:53 AM

1 Attachment(s)
Jerry: recognize this ?

Jerry Clayton 10-09-2013 10:02 AM

Yes I do----------I wish there had been a way to remove that without damaging the body----------how did the combos work out????????

Scott might see this also----------

scottj 10-09-2013 11:02 AM

1 Attachment(s)
Quote:

Originally Posted by Jerry Clayton (Post 1266474)
Yes I do----------I wish there had been a way to remove that without damaging the body----------how did the combos work out????????

Scott might see this also----------

I see everything Jerry... lol


All times are GMT -7. The time now is 08:54 AM.

Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
The representations expressed are the representations and opinions of the clubcobra.com forum members and do not necessarily reflect the opinions and viewpoints of the site owners, moderators, Shelby American, any other replica manufacturer, Ford Motor Company. This website has been planned and developed by clubcobra.com and its forum members and should not be construed as being endorsed by Ford Motor Company, or Shelby American or any other manufacturer unless expressly noted by that entity. "Cobra" and the Cobra logo are registered trademarks for Ford Motor Co., Inc. clubcobra.com forum members agree not to post any copyrighted material unless the copyrighted material is owned by you. Although we do not and cannot review the messages posted and are not responsible for the content of any of these messages, we reserve the right to delete any message for any reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold us harmless with respect to any claim based upon transmission of your message(s). Thank you for visiting clubcobra.com. For full policy documentation refer to the following link: