Change of oil and found metallic spring etc inside - need your advise.

[Jac Mac]

I dont see a failed rocker, I do see two broken rocker studs that do not appear to have had much thread engagement by the Posi Locks, the poor geometry would have created higher than normal loadings on the studs in this case which lead to the stud failures, from there on it was simply a train wreck, Andronikos has also got a video of him driving the car in Greece prior to the breakdown, did not sound healthy to me even then.

[Gaz64]

Correct.

A stud girdle would have prevented this.

Ultimately a rocker arm designed for large springs is needed.

Lucky it didn't drop valves with the rocker arm pushing on the retainer.

[Curt C.]

Yes, I should have said failed rocker stud. Corrected.

[DAVID GAGNARD]

Originally Posted by Gaz64

Correct.

A stud girdle would have prevented this.

Ultimately a rocker arm designed for large springs is needed.

Lucky it didn't drop valves with the rocker arm pushing on the retainer.

A stud girdle might have helped,maybe prolonged the studs from breaking,but sooner or later, something would have broken....or it would have dropped a valve..........when things are this much out of wack, it's just a matter of time before something fails and 690 miles is not that long a time............

David

[GH427]

[quote=Eljaro;1131926]I think a very good book for the 351W engine you have is HPBooks How to Rebuild Small-Block Ford Engines Book By Tom Monroe.

Hi Andronikos, I was wondering if you ever got any feedback from your engine builder regarding the valvetrain failure. I agree with the others who advised you to rebuild the engine yourself and the book mentioned by Eljaro above is an excellent reference. Also, I have found a DVD called "Power Building Videos - Heads, Porting and Valve Trains" explains a lot of the valvetrain geometry issues and how to aet up a valvetrain properly. In addition it also has lots of other tips on cams, rocker arms, valve springs, etc that would come in very useful if you had not done this sort of thing before.
Don't be frightened of doing this stuff on your own. You need to educate yourself as much as possible beforehand and then take your time and make sure you have done everything step by step and remember to check your work several times over. The satisfaction from doing something like this yourself is enormous not to mention that you save considerably on assembly costs.http://www.clubcobra.com/forums/imag...lies/smile.gif
Hope everything goes well for you and your engine and please post more videos on you tube when you have your cobra up and running again.
Prwxora xwris fovo
George H.

[Eljaro]

From what I see the problem comes from the valvetrain in the first place. Something dropped from there and was picked up by the oil pump and seized it, leading to the broken oil pump shaft and the oil starvation and everything else thereafter.
Basically the studs for the rockers are too short or the pedestals on the heads wrongly machined . Maybe these rockers are not designed for these heads.
The stud barely engages the adjusting nut, the rockers sit too low on the head , the pushrods are probably too short and the valve retainers probably touch the rocker sometime during their travel.
The valve springs need be much stiffer for hydraulic lifters, because the heavier weight needs additional force to push them fast enough towards the cam lobe at high revs and prevent the pushrods from banging around and jumping out of its place, which is probably what happened and made the lifters break.
If the rocker studs are so bad off, I would suppose that the valve springs were badly chosen also.
If you look at the picture in this link http://www.racecar2000.com/ad-photos/44758-mod.jpgyou will see a Windsor 406, and the stud clearly sticks out of the adjusting nut and the rockers have much more space in relation to the retainers.
I would really like to know what the engine builder has to say to this. This is a perfectly botched job and a clear Warranty case, and the engine would have to be repaired by whoever built it at no cost to Andronikos.

Of course, there is allways the possibility that the previous owner did install this UPGRADE.

[andronikos916]

Hello guys,

First of all I want to say A big thank you!!!

Since I have started that post some months ago and many of you helped me so much, you deserve (at least) to know what was wrong - and what is the current status of my engine. If I rebuilt it? How? What parts? etc etc...

I feel way more experienced now - and this is something that only with your help and by using the clubcobra forum could have been achieved.

At the moment I am not in my home PC where I do have pics and detailed part numbers and measurments to share but I finally have the engine working fine.

In couple of days time I will provide further info as promised.

BTW: The car feels so much better now. I guess it is 100% normal since it had 2 valves off before and no oil! :-) Lets see if it will last. This is what shows a good engine - right?


Once again - thank you! ...Andronikos,

[andronikos916]

Hello guys,

So I decided to go with the semi-rebuilt root, and not with the full rebuilt. Some guys might argue here but I tried to reduce the cost of the repair while making sure that the parts I will not rebuilt are in good condition.

So I did not removed the crankshaft, pistons, valves etc. A mechanic checked the crank for scratches and if it is 100% round etc... Below it is the list from the parts that I bought.

It is also worth mentioning that the old pushrods where not bended. Also the previous length pushrods where totally wrong length and hitting the valvle cap.

The correct pushrod length is: 202 millimeters = 7.95275591 inches

The previous ones where: 5/16 in. Diameter and 19.8 centimeters =
7.79527559 inches. - and guess what, the old ones where touching like
crazy the retainer caps. Now are perfect center by using a marker pain
and we checked that there is good clearances on the retainer caps.

So the list:

*Comp Cams Roller Rocker Arm Set - $279
*Comp Cams Adjustable Pushrod Checker - $17

(then after checking the length using the below links as guide I ordered the *Trick Flow Specialties Pushrods TFS-21407950 - these are the one piece design)

Finding Proper Pushrod Length - Circle Track Magazine
COMP Cams® - Pushrods
Setting Pushrods Length, Quick and Easy- Car Craft Magazine
How to check push rod length. Plain English - YouTube
COMP Cams® Quick Tech: Achieving Proper Rocker Arm Geometry - YouTube

*Comp Cams Hydraulic Roller Lifters - $209
*ARP Rocker Studs - $39
*Melling HV Oil Pump -$57
*Moroso Oil Pump Pickup - $47
*Clevite Main Bearings - $38
*Clevite Rod Bearings - $25
*ARP Oil Pump Driveshaft - $20
*Mr. Gasket Intake Gaskets - $20
*Ford Racing Oil Pan Gasket - $19
*Felpro Valve Cover Gaskets (2 Sets) - $30
*Felpro Oil Pump/Pickup Gaskets - $4

...Also the belt was not properly aligned. So we machined a small bracket so we can offset it a bit. Now after 100miles seems all going smooth. The oil psi is reading around 70psi (cold) and 55-60psi (when hot). I guess that is normal since the viscosity of a liquid is dropping when temp is rising. I am not 100% sure if the carb is 100% well tuned. I bought a thick book about Daemon carbs - and I have started reading it. I guess - this will be my 2nd post. :-)

Important:
When I got the car from the original owner (at 670miles) the oil psi was not working correct. What I mean by that?

While I was driving the car the psi gauge was showing / jumping with super fast speed and showing randomly crazy values. (example = 60-0-10-0-50 etc)... Yes I was a newbie back then - and I believed that is normal. Also the previous owner told me that this is normal and should be the gauge's fault. So I was driving the car... I am still newbie but what I am thinking is that the oil pump rod was already broken. Since that rod became two pieces (as show in a previous image) I believe that the top and bottom part of that rod contacting each other creating some fast spinning and psi and that is why the jumps on the psi gauge. Then after some miles - due to friction no more touching = no more spinning = dead bearing etc...

To conclude: the engine was with the 2 rocker arm studs broken (sine the acceleration was not good - no way like it runs now! + those spark plugs where totally wet - not idling nice + difficult to start + a lot of smoke! (I can not believe I was not able to see these signs back then). But now that I know how it should run, I guess I will know next time.

Also the oil psi rod was already broken - because of the gauge jumping readings + the oil level was more that normal...(maybe not so important the level but if the oil does not circulate = then it rests down = higher readings)

Now I still have 1 tiny thing to fix. It is the oil temp gauge. This is dead also. Any help on that guys?


Best - Andronikos,

[Gaz64]

Find your oil temp sender, remove the wire and ground it.
Turn key on, if the gauge goes up towards full scale, turn key off.

This will test the gauge and wiring is fine, and the sender is faulty.

If nothing happens, faulty gauge or wiring.

Have you got any pics of your new valvetrain setup?

[Wbulk]

Andronikos, glad to hear you got it running. Thanks for giving us the end of the story. I was curious about what oil pump rod you used being you put in another high volume oil pump. I'm not a big fan of those. I recently watched a comp cam tech video; it may have been on distributor gear types. Anyway, they talked about problems on the SBF with the oil pump drive rods breaking when using the HV pumps.

Wayne