can you spot the problem?

 

besides the fact that everything is on the opposite side ,lol.(early model 4g63) the first lifter on the inatke side is missing.

 

indeed it is, any idea how this happened? Im going to pull the head off and maybe even pull the whole motor down. The engine was running like this, on 30 psi and C16!

here is a close up


could this show up on a leak down or compression test at all? comp is 120-125 and a leakdown showed 10% on 1 and 2, and 30% on 3 and 4.

 

also, does anyone know where i can find a guide to removing the head? Do i need to remove the timing belt and alternator and PS ect?

 

surprised it didnt drop the valve in to the chamber,hmm. havent done alot of head work on 4g63. i usually send them out to be built and slap them back on so i wont tell you anything i dont know about. maybe it wasnt put back on by accident? im not sure it would show up since im guessing the valve is seated and sealed. i can see the car running since it still has one valve opening and loading the chamber. at that boost level and c16 i dont know man, wish i could help you out more.

 

well the valve spring and retainer ect is still there, so theres no way it can drop, it is just stuck closed. Hopefully it hasnt best a valve or damaged any other components. I have only had the car for a few months and only driven it once so i dont really know the condition of the engine, it did pretty bad on the leakdown test so i guess the head has got to come off for a start.

 

The interesting thing is, the scoring on the cam lobe. It almost looks like there was something there at one time, and it might have self destructed and dropped down into the oil pan. If no lifter was ever put in there, there would be no marks on the lobe at all. If the cam was set in and pushed one of the rockers to the side a little, as soon as you rotated the cam it would pop out.

 

true. that makes sense to me tk

 

i think its obvious that there was a rocker there at some point. personally i think that something went wrong, the guy who owned it b4 u said F it im just going to sell it, and now u have his mistakes. but what i dont get is, did u not test drive this b4 u bought it? u wouldnt know how badly down on power it was right?

 

did you find the rocker?

 

The lifter is there, it is the rocker that is missing.

 

it didnt seem like it was down on power, and if it was how could i tell anyway, as i had nothing to compare it to before the rocker fell off.

I found the rocker, it was sitting just underneath having a rest

could valve bouncing cause it to jump off?

Where can i find a guide to remove the head?

 

I am sure the mark on the cam is from the rocker when it came off, probably hung up for awhile and made the mark and then fell off into the top of the head.

It is a common problem. It probably happened when the car was rev'd higher than the springs could control the valve/rocker.

 

thanks Dave.

the head is coming off, cant wait to see what other jacked up **** i will find.

 

It happens. Dig around with a magnet and find the rocker. If the cam lobe only has a slight score in it, pop a new rocker on it and boost away.

I have seen 4gs with way more cam damage that run like tops.

I wouldnt tear the motor apart yet.