Author Topic: Valve cover gaskets and breathers.  (Read 3313 times)

0 Members and 1 Guest are viewing this topic.

Yellow Truck

  • Hero Member
  • *****
  • Posts: 608
    • View Profile
Valve cover gaskets and breathers.
« on: April 01, 2020, 11:29:51 AM »
I'm noticing some seepage from the covers, and it is not surprising since I've had the covers off half a dozen times without replacing them, but I'm about to make a cap for the rear breather hole on my Anson covers, and drill a new front hole on the driver side (clearance issues with the brake booster mean I can't run a breather back there).

Wondering if there is a particular gasket that will seal better - I made the mistake of putting a high flow pump in and I get a LOT of oil in the heads. The ones I have are a rubber/cork combo.

While I'm at it, I currently run a Ford Racing cap with some foam filtering, a 1" push in style. Should I be concerned about contaminants getting through?
1969 F100 4WD (It ain't yellow anymore)
445 with BBM heads, Prison Break stroker kit, hydrualic roller cam, T&D rockers, Street Dominator Intake with QFT SS 830.

Paul.

cjshaker

  • Hero Member
  • *****
  • Posts: 4449
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #1 on: April 02, 2020, 07:24:27 AM »
I use the regular rubber impregnated cork FelPro covers and don't have any issues with them, despite having them off LOTS of times to check lash and do a general look-over to make sure everything is ok. After a while, they just won't compress and seal anymore, so I simply replace them. Currently I've had the same ones on for 4 years, but they're about due to be replaced. I seal them to the valve cover and leave the head surface alone.

Why not take the opportunity to pull the rocker system and drop a restrictor down the oil hole on the head? That will help on multiple levels: less oil filling the head, better valve cover sealing etc.
Doug Smith


'69 R-code Mach 1, 427 MR, 2x4, Jerico, 4.30 Locker
'70 F-350 390
'55 Ford Customline 2dr
'37 Ford Coupe

blykins

  • Hero Member
  • *****
  • Posts: 4801
    • View Profile
    • Lykins Motorsports
Re: Valve cover gaskets and breathers.
« Reply #2 on: April 02, 2020, 08:41:38 AM »
I also use the cork ones on all my FE's.  I silicone them to the valve cover and put a layer of grease on the cylinder head.  They seal very well.

I'm with Doug, the rockers need to be restricted. 
Brent Lykins
Lykins Motorsports
Custom FE Street, Drag Race, Road Race, and Pulling Truck Engines
Custom Roller & Flat Tappet Camshafts
www.lykinsmotorsports.com
brent@lykinsmotorsports.com
www.customfordcams.com
502-759-1431
Instagram:  brentlykinsmotorsports
YouTube:  Lykins Motorsports

Falcon67

  • Hero Member
  • *****
  • Posts: 2151
    • View Profile
    • Kelly's Hot Rod Page
Re: Valve cover gaskets and breathers.
« Reply #3 on: April 02, 2020, 09:12:45 AM »
I have the covers on and off the dragster 351C a lot - best I've found so far are the Edelbrock units.  The Felpro items started to come apart after some use.  The Edelbrock ones on the dragster have been there 3 years.  I really crank down on the hold down studs and run a vacuum pump, and the lifters put easy a quart of oil in each cover on a run so I need a real tight seal on the covers.  On the door car with just exhaust evacs, the old rubber FelPro units are still holding up.

TJ

  • Full Member
  • ***
  • Posts: 173
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #4 on: April 02, 2020, 09:33:01 AM »
With the stamped valve covers I did similar to what blykins described...silicone the gasket to the valve cover.  With the cast aluminum valve covers, they’re rigid enough to seal the regular felpro cork gasket without silicone.

For breather, yeah you probably want a better filter when running a PCV valve then just a foam cover.  A while ago captcobrajet described how to route the vacuum line through the air filter which made sense.  That  way your crank case gets well filtered air.
« Last Edit: April 02, 2020, 09:35:39 AM by TJ »

Yellow Truck

  • Hero Member
  • *****
  • Posts: 608
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #5 on: April 02, 2020, 11:44:43 AM »
Thank you for the suggestions.

Regarding restricting the oil passage under the rocker - I did. One restrictor sat up where I could see it, the other one fell back into the passage. I assume they are providing some restriction. I think the oil is mostly coming up the pushrods, but I've never run the engine without the covers - I did spin the oil pump by hand and with a drill when we were doing the initial build. With the drill it came out all the lifters and poured oil out over the side of the heads.

The valve covers are cast aluminum, and I've never sealed the gasket to the cover. I'll try that. I'll get some more Felpro gaskets.
1969 F100 4WD (It ain't yellow anymore)
445 with BBM heads, Prison Break stroker kit, hydrualic roller cam, T&D rockers, Street Dominator Intake with QFT SS 830.

Paul.

blykins

  • Hero Member
  • *****
  • Posts: 4801
    • View Profile
    • Lykins Motorsports
Re: Valve cover gaskets and breathers.
« Reply #6 on: April 02, 2020, 12:08:20 PM »
Are you running a restrictor or a plug?  You don't need to oil from both sources at the same time.  What cam, lifters, and rockers are you using?
Brent Lykins
Lykins Motorsports
Custom FE Street, Drag Race, Road Race, and Pulling Truck Engines
Custom Roller & Flat Tappet Camshafts
www.lykinsmotorsports.com
brent@lykinsmotorsports.com
www.customfordcams.com
502-759-1431
Instagram:  brentlykinsmotorsports
YouTube:  Lykins Motorsports

Yellow Truck

  • Hero Member
  • *****
  • Posts: 608
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #7 on: April 02, 2020, 12:39:09 PM »
Brent,

I'm running restrictors, not plugs. The cam is a Comp Cam hydraulic roller (234/240 at 0.050 but I don't think that matters), lifters are Morels, rockers are the T&D street rockers. My understanding is that the Morels push oil out the top of the lifter and send it up the hole in the push rod. This engine makes a lot of oil pressure.

It would be nice to have less oil in the heads.
1969 F100 4WD (It ain't yellow anymore)
445 with BBM heads, Prison Break stroker kit, hydrualic roller cam, T&D rockers, Street Dominator Intake with QFT SS 830.

Paul.

blykins

  • Hero Member
  • *****
  • Posts: 4801
    • View Profile
    • Lykins Motorsports
Re: Valve cover gaskets and breathers.
« Reply #8 on: April 02, 2020, 12:58:04 PM »
Brent,

I'm running restrictors, not plugs. The cam is a Comp Cam hydraulic roller (234/240 at 0.050 but I don't think that matters), lifters are Morels, rockers are the T&D street rockers. My understanding is that the Morels push oil out the top of the lifter and send it up the hole in the push rod. This engine makes a lot of oil pressure.

It would be nice to have less oil in the heads.

Yep, you got it.  That system will oil through the pushrods.  You can plug the heads off completely.  You don't need to oil from both spots.
Brent Lykins
Lykins Motorsports
Custom FE Street, Drag Race, Road Race, and Pulling Truck Engines
Custom Roller & Flat Tappet Camshafts
www.lykinsmotorsports.com
brent@lykinsmotorsports.com
www.customfordcams.com
502-759-1431
Instagram:  brentlykinsmotorsports
YouTube:  Lykins Motorsports

HarleyJack17

  • Sr. Member
  • ****
  • Posts: 268
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #9 on: April 02, 2020, 01:33:21 PM »
Maybe a dumb question but can the same be done(push rod oiling) for OEM non-adjustable rockers? Block off the oil feed to the head entirely and only oil through the push rods? What size hole is common through the PR for this?

Yellow Truck

  • Hero Member
  • *****
  • Posts: 608
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #10 on: April 02, 2020, 01:37:05 PM »
I am still pretty new to this, so what do you suggest for blocking the oil passages?
1969 F100 4WD (It ain't yellow anymore)
445 with BBM heads, Prison Break stroker kit, hydrualic roller cam, T&D rockers, Street Dominator Intake with QFT SS 830.

Paul.

blykins

  • Hero Member
  • *****
  • Posts: 4801
    • View Profile
    • Lykins Motorsports
Re: Valve cover gaskets and breathers.
« Reply #11 on: April 02, 2020, 04:25:19 PM »
I am still pretty new to this, so what do you suggest for blocking the oil passages?

What do you have them restricted with now?
Brent Lykins
Lykins Motorsports
Custom FE Street, Drag Race, Road Race, and Pulling Truck Engines
Custom Roller & Flat Tappet Camshafts
www.lykinsmotorsports.com
brent@lykinsmotorsports.com
www.customfordcams.com
502-759-1431
Instagram:  brentlykinsmotorsports
YouTube:  Lykins Motorsports

Yellow Truck

  • Hero Member
  • *****
  • Posts: 608
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #12 on: April 02, 2020, 07:36:58 PM »
I used a pair of 0.060 restrictors for Edelbrock heads.
1969 F100 4WD (It ain't yellow anymore)
445 with BBM heads, Prison Break stroker kit, hydrualic roller cam, T&D rockers, Street Dominator Intake with QFT SS 830.

Paul.

blykins

  • Hero Member
  • *****
  • Posts: 4801
    • View Profile
    • Lykins Motorsports
Re: Valve cover gaskets and breathers.
« Reply #13 on: April 03, 2020, 04:35:34 AM »
Are they screw in?  If so, just match the thread with a solid set screw and block it off that way. 

If it's just dropped in, then just match the OD of your restrictor with a solid plug.
Brent Lykins
Lykins Motorsports
Custom FE Street, Drag Race, Road Race, and Pulling Truck Engines
Custom Roller & Flat Tappet Camshafts
www.lykinsmotorsports.com
brent@lykinsmotorsports.com
www.customfordcams.com
502-759-1431
Instagram:  brentlykinsmotorsports
YouTube:  Lykins Motorsports

Yellow Truck

  • Hero Member
  • *****
  • Posts: 608
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #14 on: April 03, 2020, 11:10:20 AM »
They are drop in, and what I noticed when I put them in (it has been a few years now) was that on one head the oil passage was tight to the dimension of the restrictor and it sat up at the top of the passage near the threads, and the other head had a much wider passage (at least up at the bolt hole where you could see it) and the restrictor disappeared down into the hole.

I certainly could get a plug machined to the two sizes. I wonder how much oil it would stop, given that they are somewhat restricted now.
1969 F100 4WD (It ain't yellow anymore)
445 with BBM heads, Prison Break stroker kit, hydrualic roller cam, T&D rockers, Street Dominator Intake with QFT SS 830.

Paul.

1964Fastback

  • Jr. Member
  • **
  • Posts: 89
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #15 on: April 03, 2020, 11:39:58 AM »
... the other head had a much wider passage (at least up at the bolt hole where you could see it) and the restrictor disappeared down into the hole.

This would bug me, personally.  I'd be worried I'd forget it was in there, or someone in the future would not be expect it and let it drop out, etc.  Maybe just an OCD thing.  I would pull the rocker shaft on that side and with the engine cold (thicker oil) put a towel over the hole and crank it over with a remote starter switch and see if it shot out into the towel.  If not, I'd probably give up.  :)

Pat
1964 Galaxie 500 2 dr Fastback, 390, 4 speed, Indianapolis Indiana

Yellow Truck

  • Hero Member
  • *****
  • Posts: 608
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #16 on: April 13, 2020, 10:38:52 AM »
I am having my neighbour machine a set of tubes to come up out of the rocker to take a push on breather, I've ordered a couple of K&N breathers and we will get that done next week when they come in.

Today I pulled the rockers off and checked the dimension of the oil passages. On the BBM heads I have they were able to take  a 1/4 threaded plug so I tapped them and threaded in a pair of plugs. When I vacuumed up the little bit of tapping debris the restrictors came flying out. They are far too small for the passage in a BBM head.

Having never built an engine before I didn't recognize how small they were compared to the oil passage. They are probably sized to a different head. In any case,  passage is now stopped and the rockers are back on.
1969 F100 4WD (It ain't yellow anymore)
445 with BBM heads, Prison Break stroker kit, hydrualic roller cam, T&D rockers, Street Dominator Intake with QFT SS 830.

Paul.

Yellow Truck

  • Hero Member
  • *****
  • Posts: 608
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #17 on: April 15, 2020, 12:36:32 PM »
Not super exciting, but a nice job by Percy (my amateur machinist neighbour made me two) lets me put a small breather on the valve cover and it clears the brake booster.

This means I can use an 8 inch dual diaphragm booster with a new set of disc brakes I'm ordering.

You will have to click on the link because I can't figure out how to embed a picture here.

https://links.flickr.com/u/click?_t=40ac9f0c38d540238d36950e58265982&_m=888f69ade8b7417abdf8c87767db86ac&_e=ZLamHGtXKn8SeO5ZxUCDDF3GaJsTuwKj-3QN8pEVPtcJHMwhLW7h6kfOac3leY6MhlxntfSgruGXbHTa_ZnZmcT7cf1aDjSkTW0LF1PJP2aq0mMzZDArq-KSg5U9QJ9fH-eIqd3BsrpYzI97WfL_zMP8fErs41eCUV8Pyu98AE2GQ1zBtAaUuOhrFM5rDj7sI7iCc-JtyxyvsIoRuqSAf4lDNuCbrDg19Yk29edvLNP8R_G8llQPl0Zqh8CGnOvrfr5HnMP-8XUi4Jovl72YOPpxrAeX3eGYgITYdHq_Rj4sos8SMnmIGZFilY9DYbhS
1969 F100 4WD (It ain't yellow anymore)
445 with BBM heads, Prison Break stroker kit, hydrualic roller cam, T&D rockers, Street Dominator Intake with QFT SS 830.

Paul.

Yellow Truck

  • Hero Member
  • *****
  • Posts: 608
    • View Profile
Re: Valve cover gaskets and breathers.
« Reply #18 on: April 16, 2020, 12:43:14 PM »
Since I pulled the rockers to block the oil passage I have to reset the lifter pre-load. Usually this is a bit fussy since I was using the EO/IC approach and turning the engine and watching the rockers is tedious.

My neighbour has a nice approach and made a clever tool to find the base circle on the cam lob of each cylinder. He made a little tool he drops over the distributor and follows the rotor as it points to each spark position. I can set the pre-loads in about five minutes.



1969 F100 4WD (It ain't yellow anymore)
445 with BBM heads, Prison Break stroker kit, hydrualic roller cam, T&D rockers, Street Dominator Intake with QFT SS 830.

Paul.