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Discussion Starter · #1 ·
Well, I pulled the passenger side valve cover off today (not sure why) and noticed that #1 and #3 rocker arms were VERY loose! They were so loose I could lift the rocker up about 1/4 inch off the stud. I know they naturally are supposed to be a little loose when the valve is closed but I don't think they are supposed to be THAT loose....are they? Apparently, I've been mistaking the rocker noise as a header leak. Could this be the cause of the drop in oil pressure or did I just discover another problem that need fixed now?
 

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Nope not THAT loose. adjust and try it again... the very loose rockers MIGHT be the source of the O.P. problem....
 

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This thing should be running like crap. Adjust valves and check lift. You may have lost lobes on the cam.
 

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A lifter that's too far out of place will block the oil passageway through the gallery, but it would likely cause a SPIKE in pressure rather than a lowering of pressure were it to be that far out due to the new restriction of flow from there forward.

I must say though that a re-adjustment to 0 lash plus 1/2 turn will put you back to rights with a hydraulic cam, then you can run it again to check oil pressure, or run the drill on the dist shaft.

But to me is sounds like my suggestion of you buying a Gasket set for it and taking it out and apart to find the problem before breaking the motor is the most sane way to approach it.
 

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No one has thought to say that the loose lash is due to those lifters not getting any oil pressure??? If those lifters are free of oil then the lash will be lost because the oil got pushed out by spring pressure. Garry is 100% correct in saying that the lifter will block the oil galley and spike the pressure, Your issue to me sounds like you lost the galley plug under the intake the more I hear about it, and will cause oil loss to the lifters in a heart beat.
 

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Discussion Starter · #6 ·
No one has thought to say that the loose lash is due to those lifters not getting any oil pressure??? If those lifters are free of oil then the lash will be lost because the oil got pushed out by spring pressure. Garry is 100% correct in saying that the lifter will block the oil galley and spike the pressure, Your issue to me sounds like you lost the galley plug under the intake the more I hear about it, and will cause oil loss to the lifters in a heart beat.
Well what would cause that plug to come out (if it did)? When I did the intake gasket change not long ago, I did not see anything out of the ordinary in the lifter galley, unless it popped out between then and now.

I'm going to have to buy a few things from Summit before I can really do much else. I want to get a new oil gauge(and hardware), oil priming tool and a needle valve gasket kit, for my holley, for a leak I have there yet...lol
 

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Just today at work the maint mgr asked me about the ford engine in our old old 15000#lift truck...they just tuned it up, it's backfiring thru the carb and clattering like crazy... Sounded like if mech tappets they were way loose, but he said it was quiet till they tuned it up. Suggested pull vc and see if its loose/ getting oil. No oil up top. Looked at it, new distributor...yep, they just swapped it, didn't check the driver to the oil pump, bet him a buck the driveshaft fell out or broke...reluctantly he pulled it out " put it in myself, I know it's ok" situation, but it was rounded off...suggested he put a driver in a drill and check pump, it pumped right up.
Luckily the thing was backfiring from worn cam/collapsed lifters not opening the valves or they woulda ran it till it locked up. Luckily it's so old/ loose, hopefully the bottom end survived on splash. Kinda think a oil gage or idiot light might be something to add to the repair list...crazy how industrial stuff gets neglected and still runs.

Anyway, just had to share, doubt similar causes, but sounds like similar symptoms
Tim
 

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No one has thought to say that the loose lash is due to those lifters not getting any oil pressure??? If those lifters are free of oil then the lash will be lost because the oil got pushed out by spring pressure. Garry is 100% correct in saying that the lifter will block the oil galley and spike the pressure, Your issue to me sounds like you lost the galley plug under the intake the more I hear about it, and will cause oil loss to the lifters in a heart beat.
this also covers FE.
a lifter to far out will not block the oil galley. .

lifters in the bores block it .
 

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A lifter that's too far out of place will block the oil passageway through the gallery, but it would likely cause a SPIKE in pressure rather than a lowering of pressure were it to be that far out due to the new restriction of flow from there forward.

I must say though that a re-adjustment to 0 lash plus 1/2 turn will put you back to rights with a hydraulic cam, then you can run it again to check oil pressure, or run the drill on the dist shaft.

But to me is sounds like my suggestion of you buying a Gasket set for it and taking it out and apart to find the problem before breaking the motor is the most sane way to approach it.
thats is far out .lol
 

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When you performed the cam upgrade, was any modification(s) done to the valve-train? Were adjustable rockers installed and if not, how did you arrive at proper geometry and lash?

mustang42782

Re: *****UPDATE**** On Low Oil Pressure
<hr style="color:#ffffff; background-color:#ffffff" size="1"> No one has thought to say that the loose lash is due to those lifters not getting any oil pressure??? If those lifters are free of oil then the lash will be lost because the oil got pushed out by spring pressure. Garry is 100% correct in saying that the lifter will block the oil galley and spike the pressure
Or the lifters have failed. The grooves around the lifter body will ensure oil flow around a lifter unless it (lifter) shoots out of the lifter bore (complete failure), at which time you will have complete loss of pressure. The orifice in the lifter body is where oil pressure is supplied to the internals of the lifter (hydraulic). The pressure will not spike as the pump relief valve will (should) prevent that.

This period design valve-train is not adjustable other than by substituting differing length push-rods for service (unless the valve-train has been modified).
 

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Well you can shim the pedistal for adjustment. I'm assuming he's either wiped a lobe, got a collapsed lifter, or a bent pushrod.
 

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NO! A Lifter 1/4 inch UP WILL block the galley passage! Look at the WIDTH of the oil passage. The mid range is about 1.4 inch...



Loos at this 351 lifter.
FE , look at the W type oiling system, one of the best systems .

next time you have one apart , take a look at how much is block by the lifter.

btw . all hyd lifters today interchange with all 221 thru 351 and Clevelands plus the BBF also 240/300 6 cyl.

Edit . ALL Ford lifters for engines posted
 

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Discussion Starter · #18 ·
To answer some of the newer questions here:

1) These heads are '74 windsor heads with some mild port work, over sized valves (1.94/1.60) and stock rocker arms. I got all the matching valve springs, retainers, etc when I bought the cam.

2) I set the lash by first setting it to 0 lash and gave the nut another 1/2 turn. (standard procedure for hydraulic cams)

I doubt a push rod bent or a lobe wiped because the motor ran fine when I noticed the 0 oil pressure(when stopped) and drove back home 15 miles. There was no misfire or back firing through the carb.

I agree that it should run like crap with the rockers loose like that, but I assure you, it doesn't. I always passed off the rocker noise as a leaky header gasket or collector leak, until I pulled the cover off yesterday.

BTW, if I buy an oil priming tool and see oil at the rocker arms, what will that rule out....the oil plug in the galley is still in?
 

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BTW, if I buy an oil priming tool and see oil at the rocker arms, what will that rule out....the oil plug in the galley is still in?
It could, though it won't tell you if it's that, or a jammed bypass (releif), or other. Anyway, you don't need to buy a priming tool. Just use a socket and extension, but tape the socket to the extension. You only knock sockets off into the oil pan when you're trying not to. ;) A 1/4" drive extension fits neatly into a 1/2" drill motor, or a 3/8" drive adapter can be used in any drill motor or hand drill.

David
 
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