jimtanner

Does anybody know why a cam would seize up?This caused my timing belt to brake.Replaced belt,tensioner,water pump and seals.Cam on passenger side wouldn't turn easy with a wrench with the belt off.It freed up but now has a ratteling noise when running.Can anything on the head be repaired or does it have to be replaced it that is where the noise is coming from?????? I'm pulling the valve cover tomorrow to see what it looks like.THANKS EVERYBODY

jimtanner

Does anybody know if it has bearings? Toyota dealer said the head had to be replaced.Rained all day .didn't get to work on it.

FattyCBR

The cam does not have bearings. Let us know what you find.

Glenn

Lack of oil is the only reason I can think of for the cam to seize.

jimtanner

Thanks for the reply. Was full of oil so I don't know what happened>I'm going to try to get the valve cover off tomorrow and pull the cams.i'll post what I find.THANKS

Weasy2k

Cams have a oil sleeve bearing cap like your crank....

I think you might have either:
Cracked the cam...
popped a shim
valve spring failure

all of which would jam up the cam...

jimtanner

Thanks for reply.I hope it's a shim or something simple.I hope it is not the head bad. Have you ever seen or heard of this problem?

Weasy2k

well a busted shim can cause havoc in a head....

this has happened before in other engines but not a 5vz before that i have seen...mostly dirty oil can cause it.

jimtanner

what havoc do you mean? Should I be afraid to look? This is my work truck and I need it on the road. It has 212K miles.

Weasy2k

well your cams are spinning quickly....
a bunch of lobs and gears going around...now stick a piece of metal in the gear....or around another lobe....not so happy....

rip taht valve ocver off

Mr. Bob

I saw one with a siezed cam a while back... When I got the belt and all that apart the cam was VERY hard to spin... Although full of clean oil, it looks like the one I saw was due to poor maintinance. There was a lot of sludging in the engine. The sludge starved the cam of oil.... This one had a touch over 120 000 KMS ( 75 000 Miles )

Weasy2k

Yea its a huge problem in these v6's....i run synthetic because of it.

If that is the case then yuor going to need a new head as you cant replace the bearing "caps" at all.

MTL_4runner

Most likely that head is toast.....and yes, sludging has been a problem on these motors if poorly maintained for any period of time. Cheapest place to get a new head is probably the junkyard or eBay if you can fine just the head for sale. My worry would be that if the head seized on one side, who knows how long until more stuff begins to happen.....I might opt for an entire used motor and swap out your old one. Then if the parts aren't too bad on the motor you pull, you can probably piece them out and make some money back.

jimtanner

Thank you everybody for the replys. I'm about to get into it. Had to work this morning.If oil is changed regular,how do you keep sluge out??? THANKS AGAIN

jeremys73

let us know what you find out

Weasy2k

its the type of oil and the length between changes...those 2 are key

I pulled apart the cams in my 96 taco with 230k miles on it and the insides were shiny alluminum colour....
On the other hand i have another 3.4L going into my mr2 that is apart with 68k miles...and its caked in brown sludge crap.

Thats teh difference 30 bucks per oil change will give you (synthetic vs normal)

Mr. Bob

So so true Johnny

jimtanner

wanted to let everybody know the front cam cap had seized. there was a little sluge,but not much.I guess it doesn't take much in the right spot.I'm going to change type of oil I use.I am about half way to getting the head off.I really thank everybody for the help. Does anybody know about the rebuilt heads?

jimtanner

Forgot to ask.Does anybody have any contacts with the auto"daewoo"?My wife got one for her daughter and the engine is junk from what everybody says.I want to put a good motor and transmission in it.Any ideas out there?

Weasy2k

DO you have any picturs of it?

how are the bearing caps?