camshaft seized

[mattcruff]

Okay, so i was rebuiling a 83 200s engine thats just been sitting in my shop. the only thing that seems to be wrong with it is the bushing at the end of the cam is locked onto the cam. So my question is... how is this oiled? How does the oil get from the bottom of the engine to this? just curious because i dont want to press the bushing off and install a new one and then get this problem again.

heres a pic incase you dont know what im talking about

[mattcruff]

i mean does the oil just travel up the chain and sling on the valve and etc? or what?

[AutoXer]

has a oil pump

[mattcruff]

i know it has a oil pump. but how does it get up there. i dont see any oil galleys

[rdlsz24]

The bolt hole that needs an o-ring on the cylinder is an oil passage I believe.

Rob

[mattcruff]

so im guessing since mine doesnt have an o ring, no oil up top?

[rdlsz24]

Yeah that could be your problem.

Rob

[Macs]

nevermind, i was too late

[mattcruff]

thanks guys, i think im just gonna put a new cam and bushing in it and then run it till it does it again. atleast now i know how to correct the problem.

[mattcruff]

i think i will blow some air through there and make sure it aint clogged.

[rdlsz24]

Don't forget the o-ring this time! Probably a 25 cent part. You wouldn't have to get it from the dealer. Any o-ring that size will do.

Rob

[SWIGIN]

why did the cam seize in the first place.......replace the oil pump or at least open it up and give it a look over.

i have forgot the oring on these motors in the past and it ran fine....the dowl pin seals pretty good and the oil realy never touchs the oring.

that being said i would use one anyway but my point is thats not the reason the head didnt get oil.

[Howdy]

thanks guys, i think im just gonna put a new cam and bushing in it and then run it till it does it again. atleast now i know how to correct the problem.

You will be wasting a cam unless you find the problem. To help figure out the problem we need some questions answered.

1 ) Was the top end rebuilt lately ( low hours since rebuild )?
2 ) has the right side cover been removed lately 9 Clutch cover )?
3 ) was the motor ran without oil?
4 ) Is the black rubber piece in the hole on the Head ( near the bushing for the cam ).
5 ) Does it have gasket sealant around the cylinder base, head & cylinder, right side cover?

The reason for these questions is that there is small holes in the way the oil travels to the top end. If one of these are plugged up it will cause the cam to be starved of oil. The black rubber plug also is needed for the oil to get to the topend.

Howdy

[leevarnado]

hey rdlsz i got the same picture here but its a little different.i traced the oil flow in blue so that you could see it better.check it out mattcruff.74919

[kdagenais]

You will be wasting a cam unless you find the problem. To help figure out the problem we need some questions answered.

1 ) Was the top end rebuilt lately ( low hours since rebuild )?
2 ) has the right side cover been removed lately 9 Clutch cover )?
3 ) was the motor ran without oil?
4 ) Is the black rubber piece in the hole on the Head ( near the bushing for the cam ).
5 ) Does it have gasket sealant around the cylinder base, head & cylinder, right side cover?

The reason for these questions is that there is small holes in the way the oil travels to the top end. If one of these are plugged up it will cause the cam to be starved of oil. The black rubber plug also is needed for the oil to get to the topend.

Howdy

Howdy, What symptons would you experiance if the rubber piece is not in the head (#4 above)? Currently am experiancing a temporary seizer after 30 minutes of running on a 200S. After about 5 minutes it will turn over and run fine again.
Thanks In Advance!

[SWIGIN]

sounds like a bad oil pump to me.....or at least a bad oil suply.

you need that rubber plug for starters but did you ever open up the pump?

[kdagenais]

sounds like a bad oil pump to me.....or at least a bad oil suply.

you need that rubber plug for starters but did you ever open up the pump?

Yes! and just changed the pump with another known good pump and found sludge in the engine blocking one of the passages for the oil pump. The thing that is confusing me is even after the seizure I take the valve caps off and while running it is spitting oil all over the place. Have a feeling some sludge is starting to plug the passage again. Just don't feel like pulling the bottom end apart again and I thought I cleaned it really good though.

[SWIGIN]

this is what you get for half assing stuff together.

tear it down to nothing......clean every part.......put it back together and sleep well knowing its clean.

[kdagenais]

this is what you get for half assing stuff together.

tear it down to nothing......clean every part.......put it back together and sleep well knowing its clean.

Well I did tear it down entirely and cleaned everything as required and was amazed at the amount of oil sludge in this engine. Never seen that much sludge in a small engine before. Almost like the guy never changed the oil ever. That is why it is so discourging when you try to do it right and still goes wrong. Anyway looks like will have to pull it apart again to see if it picked something up somewhere that I didn't see.

[SWIGIN]

hahaha.......then your clean and my clean are 2 different things man.

either that or your tear it down to nothing is different from mine

[Howdy]

Just because oil is spitting out doesn't mean it's getting enough oil. It sounds like something is plugging the oil passages.
Howdy

[kdagenais]

Just because oil is spitting out doesn't mean it's getting enough oil. It sounds like something is plugging the oil passages.
Howdy

Howdy, what is the purpose of the plug in the head? Seems to me that it would restrict the flow or at least redirect it.

[Howdy]

I have always thought of it as like a check valve. The rubber seals the hole while it's not running to keep the oil up to the head. Then when you bstart it the oil is lubing the cam right away. With out the plug the oil drops back to the bottom, when you start the motor up the cam runs some what dry until the oil gets back up there. Running the cam dry will kill it quickly.
Howdy

[Dirtcrasher]

To me: that rubber plug was/is merely part of the machining process. They drill right through and if it wasn't plugged, the oil pressure would be lost there and in the wrong place....

Without it, I believe the cam doesn't get the lube it needs and it will score and seize up.......

Many oil passages get drilled through and then plugged on one side in order to direct the lube where it needs to go....

[SWIGIN]

To me: that rubber plug was/is merely part of the machining process. They drill right through and if it wasn't plugged, the oil pressure would be lost there and in the wrong place....

Without it, I believe the cam doesn't get the lube it needs and it will score and seize up.......

Many oil passages get drilled through and then plugged on one side in order to direct the lube where it needs to go....



ding ding ding......we have a winner

[Howdy]

At least we can agree that without the plug the cam don't get the oil it needs. ;)
Howdy

[boosted96cobra]

So after you fixed it, your worried something is wrong because when you pull the valve cover oil is flinging all over the place? Oil is pumping up to the head, oiling the moving parts like the cam and rocker arms, which are all moving around or up and down rapidly, causing oil to fling. That is what it is supposed to do. I'd be worried if I pulled the cover and there wasn't any oil.

I don't care if it is a car or atv or something else, if is an OHC engine and has sufficient oil pressure with the cover off, it is going to fling oil around or it isn't going to last very long.

[Erics350x]

If you used any sealant on the topend, that your problem. I'd start by pullin the head and re-cleaning all the passages. I've got a head, cam, and rocker box i'll sell you cheap if you need it.