Aviator Mel

So I found this bolt has sheared off the camshaft pulley ! How do you get that out and has it done any damage to the valves or cam ? Any thoughts ? Ha, no wonder it wouldn't start !

Marc

As long as the pulley is still on the key it shouldn't stop the motor from starting/running.
It looks like both cams are still in alignment.
It also looks like that is a very fresh break?
They don't normally just break on their own.

Valves, pistons and cam should be ok depending on why it broke.
What happens if you try and rotate the crank? Does everything rotate?
I think there's more to this story..

Aviator Mel

The engine will crank but not start. It was all great last Friday when I parked it. Saturday morning it would not start, thought the starter was toast as it cranked real slow and made a sound like no compression. I see this bolt today after getting the cover off, also there is a puddle of coolant along the side of the valve cover under the intake ! There is a crack or leak somewhere. I wonder if coolant had leaked in the cams and caused a hydrolock causing the break maybe ! I have a suspect HG leak too and put in some block sealer 4 days prior to this happening. I can't see how that could be related as the motor was running great.

When I bought the truck 3 years ago I had the timing belt replaced, not saying the shop did this, but the bolt that has snapped has had a wrench on it, someone has tried to turn the pulley because the bolt is rounded off a little. Why the hell would it snap under normal running ? It must have had some stress on it previously, or something just happened on Saturday morning as I cranked it.

There are no other noises when I turn the engine with the key, so does not sound if there's any other damage been done. If that thread can be got out then a new bolt might be all it needs.

wyoming9

iTrader: (1)

I have to agree there is more going on here .

The only way to have that bolt break is by trying to turn it

The pictures don`t show enough detail to tell I wonder if it broke when the timing belt was done and was holding on by just a tiny piece .

Just where did you find the head ?? Did it do any damage to the belt or any other parts

Non interference engine the bolt head may have caused more problems

Malcolm99

Sounds like you have more than 2 issues, someone over torqued the cam bolt as you described it rounded off which is disturbing and concerning on its own, perhaps the broken bolt took out a crank sensor causing a no start and making it sound like you have no compression, and your leaking rad fluid on the top of your motor as you described it so perhaps it is coming from the throttle body or associated coolant lines - I realize you've been chasing leaks for awhile now so you should have narrowed it down and either and concluded its source(s) or determined its a HG leak.

aowRS

That's a first! Very normal to remove the cam wheels during a timing belt job in order to replace the cam seals - I did it last year. The cam bolts have a specific torque value. I suspect whoever did the last timing belt job on your truck slammed that bolt on with way too much torque. The cam wheel is keyed, so the bolt is only serving to hold the cam wheel to the end of the cam. It's not under any considerable strain.



Andreas

Aviator Mel

Good to know. So if I can get that remaining thread out I should be good.

Dirt Driver

No, quite the opposite.
A key is there just for alignment and the bolt is there to provide clamping force to keep things from moving. Keys are often made of softer material so when slippage occurs they do shear without destroying the keyway.

TheDurk

Exactly. Which is what I suspect happened and why it won't start. Yes, the PULLEY still shows as being in time, but we have NO IDEA where the cam shaft is clocked to. I bet that key is sheared and the cam shaft is several to many degrees out-of-time from the pulley. It may not be rotating at all with the pulley, for all we can tell from a static pic.

It should not be that hard to get the broken thread out of the cam out now that the clamping force is removed. A left hand drill-bit followed by an extractor should do the job. I'd hope the issue was just idiot with an impact where it had no business being used, so I'd suggest put a new key, bolt, and belt on there and give it a try.

Aviator Mel

All good theories and suggestions and advice, thanks, It's so friggin' cold outside that I am loosing feeling in my fingers after 5-10 minutes. It's gonna have to sit outside for a while before I can start investigating further. I too think the camshaft is right out of time from the pulley by the sound it was making trying to start it, that was the conclusion a few of us here all thought.

I had the shop replace the valve cover gaskets a year ago, they said the cam seals were good so did not touch them. The timing belt was done 3 years ago. The vehicle was last in for a compression check a month ago, but they wouldn't have had the T-belt cover off surely.
The compression test showed #2 at 150 and #6 at 250, why would it be so high ? They said the exhaust valve was probably bad on #2 though.

Think I said earlier, but there was a puddle of coolant on the top there along the valve cover, could that have been forced up through the valve cover gasket from the head ? I also think I am dealing with either a cracked head or HG issue. I need to remove the plugs and see in the cylinders too.

Malcolm99

I find it hard to believe the hard spring pin sheared and the cams ended up perfectly aligned and kept even tension on the T- belt but its very possible and easy to check by tapping the cam out of position just slightly to see if the spring pin stays in place or moves with the cam gear, but to far and you'll have to do a timing belt job for nothing if the pin is intact.

I would perform another compression test, throttle wide open fuel system disconnected, but it won't really tell you much in regards to head gasket unless you see rad fluid spit up or you get 250 psi again on the same cylinder because its full of rad fluid.

No you cannot get rad fluid from a valve cover gasket or the Head gasket to the top of the motor, it has to leak from the Throttle body or associated lines like I previously mentioned.

Keep it simple before guessing the worst, if you don't smell rad fluid out your exhaust chances are its not a leaking head gasket, and if the cams are aligned and you crank it over and they still are aligned than chances are the cam didn't shear the spring pin. But I could be totally wrong!, hopefully you get the remainder of the cam bolt out. Again that is a big piece of metal to be rolling around in the front cover, where did you find it upon inspection.,