Broken Camshaft

[Gerry F]

Just removed my RH cam cover to identify complete loss of compression in No. 5 and 7 and this is what I found! Not gone further than this so far but noticed running rough after last outing and would not idle (no surprise!) so did a compression test after usual check on electrical bits...nada on 5 and 7...rest OK. Removing cam cover shows camshaft break over 7, broken last cam cap and a shattered tappet bucket over 5 with shattered fragments over both areas. Apart from the obvious "full head off" ...has anyone experienced this before and tried any other way (clean up, new cam and fingers crossed!) or whatever? Any technical and practical experts out there (especially South Worcestershire area) .

[Phil S]

at the best it looks like 1 valve/piston..let's hope for the best

[DJT]

Same reply as I gave on FB:

I’d say that, as a minimum, you are looking at a replacement head. That one is toast. The camshaft bearing caps are line bored, so getting that done oversize, with a new cam and trying to find suitable shell bearings is probably more than the cost of a good s/hand head. What caused it? You won’t know until it is removed and everything inspected.

[barkerwilliams]

https://www.ebay.co.uk/itm/292211153991?ul_noapp=true

no connection

Alan

[richardthestag]

that head is a boat anchor.

reckon it was running a tight cam because it had been skimmed and not line bored

sorry for your pain

[flying farmer]

That all looks a bit of a mess!
I can only think the cam bucket has disintegrated and the shrapnel has got caught in the rear cam lobes causing the breakage of the cam.
I would be surprised if there wasn’t any piston to valve contact.
apart from the cam bearing damage I would have thought the cam bucket bore would be wrecked on the one that shattered, which may be more of a problem than the rear bearings and cap.
you will know better when the head is off and stripped

[garyf]

Wasn't there new heads from the owners club being tested?

[new to this]

Wasn't there new heads from the owners club being tested?

Yes but there not ready yet

Dave

[Ritchie6]

I didn't know until recently just how brittle cam shafts were unitl I watched one of those car restoration shows. I can't remember if it was Car SOS or Fantomworks but anyway they ordered a cam shaft on-line and when it arrived apparently it had been dropped in transit and was in several pieces and they actually commented about how fragile they can be

Richard

[brian0443]

Gerry. To coin a phrase Snap!

I have just found your posting on Broken Camshaft.

Interested to hear how you got on and what damage occurred and what your course of action has been.

I have the same problem, Rejoining motorway from Services last Sunday when throttle stuck wide open in second gear .Don't know how fast I was travelling but revs 'filled the clock' and the engine went in a few seconds. LH camshaft broken with damage to No 7. RH bank camshaft seems OK but No 8 trashed. I have the heads almost off so today/tomorrow I'll have an idea of what further damage has been done.

Brian

(fellow sufferer!)

[trunt]

WOW..

Thats a good thing to make me hit the ignition key as soon as I can!!

I know its not easy in the heat of the moment but it will!

[flying farmer]

I am so glad most of my cars have rev limiters!

Many years ago I was at Prescott hillclimb talking to a Ferrari owner who told a tale about a a Ferrari owners club track day at Silverstone. The owner of one of those incredibly expensive 1960s 250GTO models hit neutral when shifting gear and grenaded the engine.
He had to have another block cast and a crank machined from billet as well as all the other bits and pieces. I can't remember how much it cost apart from it being over 6 figures about 30 years ago.

I recall the cost of a clip on the coil rev limiter being about £40 at the time as I had one fitted to the 3.9 Rover engine in my Toledo which I used for Drag racing. I bet the Ferrari owner wished he had fitted one as well!
Not long after I passed my driving test I was using my dads Austin Princess 2200 to take my sister to a dentists appointment and a frayed throttle cable caused exactly the same problem when overtaking another car in third, fortunately the acceleration was not as rapid as a Stag in second and I managed to turn off the ignition without applying the steering lock!

I hope your damage is repairable without having to source another engine.

Neil

[Rubce]

Hi Neil

How would I fit a rev limiter to either of my cars?

Regards

Bruce

[Motorsport Micky]

For anybody who wants an over rev limiter they are available on e bay, or many retailers specialising for motorsport purposes, such as this.
https://www.merlinmotorsport.co.uk/s...al-rev-limiter
Available for 4-6-8 cylinder cars. Easy to fit, clips onto the coil, comes with instructions, but they won’t save your engine from a mechanical over rev ie selecting 2nd is when doing 70 mph. !

Micky

[NickA]

that head is a boat anchor.

I sold two heads for reconditioning that had broken camshaft bearings due to oil starvation. They had never been skimmed but they *are* salvageable and certainly have value. Don't just skip them