bent cam locating pin

[400ZED]

When I pulled my original cams out I noticed the locating pin in one intake cam was bent.
I have since put the new cams in the vehicle and it has been going slightly down hill. I am nearly 100% sure that the gear is moving on the cam and this is what is giving me troubles. I did the cam bolt up tight like really tight.

The pin in the cam is only a location pin not a drive pin it is too small it is a friction drive between the pulley and the cam.

Has anyone run into this problem and more importantly has any one found a solution to this problem?

help would be greatly apreciated!

 

[1UZFTE]

400ZED
I am not quite sure what you are refering to ,.. but if its the drivepin for the front cam gear and you need a spare one let me know
I will have alook in the shed as i am sure i will have a spare?

Or are you refering to the new camshafts you have don't have a large enought drive pin to suit the standard front camwheel and this is causing play?

J

 

[Peewee]

You've got me confused too.
I thought the cam gears were put in place by keyways, like crank pulleys.

Sounds more like the tensioner is letting go.

 

[1UZFTE]

Hmm ok i think i am with you

I am wondering if the bolt is bottoming out before it pulls the campulley up full against the camshaft, the original pin being bent would suggest something in the order of this
Another thought, is it the original bolt?


You did edit that original post? or did i just read it better the second time?

 

[sleeperz]

the last bent pin i saw was on a chrysler v-6 mits/or nissan. the belt had jumped and was from a strike from piston to valve/maybe valve was repaired before you purchased motor.it's easy to overlook unless your changing cam seals

 

[400ZED]

I did not edit that post you may have just read it better.

The cam pulley is Located by a pin it is not a drive pin it is only there to locate.
My new cams fit fine Just like OEM. There is no Keyway.

The Cam pulley is a friction drive that is why the Torque Spec for that Bolt is so Darn Tight. 1uZfte you could be right the bolt may be bottoming out. but that does not explain why i had the problem on the original cams.

The really weird thing is my car did had a bent pin when i removed the original Cams.

i put a new pin with the new cams and it has moved timing again.

anyone know of some good loctite product to use on this sort of application.

 

[Peewee]

There are many loctites.

The two main ones, I forget the number, but one NEEDS heat to be removed, one just needs a lot of force.

I'd recommend the latter, just ask at any place for that stuff.
I have the number at home if you need it.

 

[Zuffen]

Rather than bodge the repair find out what the problem is then fix it.

You won't like trying to remove the pulley one day when you need to exert 200kg of force and break something.

 

[ozvenom]

bent pin!!!

I have seen a couple of examples of the location pins being sheared off both times it was cause by an oil shortage. the front right hand cam bearing is the last to recive oil from the pump. thus when you have low or no oil pressure the bearing runs dry and seizes the cam which inturn shears the pin off.
Maybe not the cause in your case but was there any scoring on the front cam bearing surfaces?
It only needs a slight jamup and the pin goes its the weak link.

You could always dial the cams in and drill a new location pin hole.

Regards Oz

 

[400ZED]

Zuffen i have thought of that it would not be nice removing it later.

OZ
the bearing s are fine
you are right the pin is only a locater.
Would a second locating pin help transfer much load?

The vehicle has a very ocasional miss. it happened with both motors so it is a wiring/ computer/ sensor problem.
but it mises realy sudenly and very violently. it can be felt through the drive line it feels like the engine dam near stops for a fraction of a second. this could be slowing the crank and the enertia of the cams could be enough to slip the pulley.
I only thought of this last night.
so my question is why does it miss and how do i stop it. there is an electronic gremlin easy fix. NOT.

 

[Peewee]

What ECU have you got?

When I wired my Microtech, I wired the Crank Angle Sensor backwards.
The timing was going from about 30deg BTDC back to 10deg from about 4000rpm up.
ECU only threw a 'RPM error' code.
The timing on the datalog looked normal, but you could see it plainly with a timing light (being aftermarket ecu it did it in neutral too, not just under load).

Does yours do it in neutral?
Check it with a timing light, could be timing like mine was.
Failing that, whack it on a dyno, and check the AFR's etc when it happens.
It will most likely be very simple.

 

[400ZED]

I wish it was simple
It only misses once - twice a month. if it misses at idle it stops instantly.
this thing has lived on a dyno that thing i have done something like 60 power runs during three full tunes and a couple of clean ups.
I am running wolf. it runs like a dream 99.9% of the time. but it is not just a miss it feels like it is firing like 60 degrees early and trying to stop the rotation of the crank.
It is rather harsha plain miss fire would hardly be noticible.

 

[Peewee]

Ahh, thats a very very intermittant miss isn't it!

I'm guessing the Wolf doesn't sense any errors when it occurs?
Can you datalog it? See if the ignition, or battery voltage, or something changes?
You've probably tried this already I know, just worth asking.

 

[400ZED]

I have not been able to watch it with the lap top attached. so i can't datalog anything. bummer.
it will seeming ly happen when ever it wants. what ever gear whatever load.

my other thought over night wasthat it could be a drive line snag like it is grabbing 2 gears at once.

I am lost i am somewhere i don't know where i am.
it is a bit too much for me.